This is the residual home for subject matter, not elsewhere classified, relating to communication by means which are in part or in whole electrical.
Communications is defined, for the purpose of this definition, as being the handling of information or intelligence and is not restricted to the conveying of said information or intelligence between geographically spaced points. (Thus, a traffic obstruction light which merely marks a safety island is a means for communicating information or intelligence, viz., the fact of the presence of the traffic island).
Information or intelligence is defined, for the purpose of this definition, as being the subject matter which is handled by signaling systems or signaling devices (such as telegraph systems) or by that portion of nonsignaling systems or nonsignaling devices (such as power supply systems) which is designated in the arts as having a control function (such as the supervisory circuits which control the circuit breakers of an electric power network).
Handling, as used above, is defined as being the active coaction between the tangible communication system or device and the intangible information or intelligence, and such coaction may assume various forms, such as transmission, storage, exhibiting, etc.
(1) Note. Since Class 340 takes, under the class definition, only those electrical communication systems which are not elsewhere classified, the search, in order to be complete, must, in appropriate instances, extend elsewhere. See Lines With Other Classes, below.
(2) Note. The combination of the subject matter of this class (340) and art environment is generally classified with the art environment where that environment is significant, either by virtue of a significant disclosed relationship or by virtue of a claimed relationship. Where the art environment is recited by name only, the combination may be classified, in some instances, with the art environment, and in others, in this class (340). For a list of some of the other classes which contain pertinent subject matter, see the classes referred to under SEARCH CLASS.
(3) Note. This classification was produced in 1952 by making official the unofficial digests which had been established by the Examiners of Division 42 during the period from about 1910 to about 1942. A caveat is given: While it is believed that the titles and definitions are reasonably correct, no assurance can be given that all of the patents, issued prior to the date of reclassification, are in the proper subclass, since the individual patents were not read during the reclassification project. Consequently, in making a thorough search in this class, it is advisable to investigate every
subclass which may possibly be pertinent and not, in order to shorten the search, to rely on the principle of superiority of subclass subject matter because of position in schedule, since the principle is applicable only in classes where each patent has been analyzed and placed in the schedule in accordance with that portion of the disclosed subject matter which is claimed.

LINES WITH OTHER CLASSES AND WITHIN THIS CLASS
Since Class 340 takes, under the class definition, only those electrical communication systems which are not elsewhere classified, the search, in order to be complete, must, in appropriate instances, extend to Class 178, Class 246, Class 250, Class 332, Class 343, Class 346, Class 348, and Class 379. See References to Other Classes, below.
LINE BETWEEN CLASSES 116, 250, 340, AND 343
Class 250, Radiant Energy, for signaling systems of the radiant energy type. Such signaling systems are coextensively classified in Class 343, and the class definitions of these two classes should be consulted for the line between Classes 250 and 343, and the class definition of Class 343 for the line between Classes 343 and 116. Note that Class 340 provides for telemetering along a radiant energy beam and for signaling systems having a radiant energy responsive detector.
LINE BETWEEN CLASSES 342, 250, 340, AND 343
Class 342, Communications: Directive Radio Wave Systems and Devices (e.g., Radar, Radio Navigation) appropriate subclasses for signaling systems of the radio wave energy type. See the reference to Class 250, supra, for the lines between Classes 250, 340, and 343. See Class 343 for antennas with a signal, indicator, or alarm which is responsive to the scan, sweep, or orientation of the antenna; and for antennas with a signal, indicator, or alarm responsive to some other condition of the antenna. See subclass 700 of Class 343 for certain classification lines involving antennas and signals, indicators, and alarms.

SEE OR SEARCH THIS CLASS, SUBCLASS:
901 through 996, The following conventions will apply to the definition of these subclasses: (a) A signal is an information-carrying wave; (b) A indicator is a device which makes information concerning a condition available. (c) An alarm is an indicator which makes information available only upon the occurrence of a preselected state of the condition.
289 320, for a significantly recited electric signaling system.
533 538, 288, and 310.01 for the combination of a Class 340 system and a Class 178 system.

REFERENCES TO OTHER CLASSES

SEE OR SEARCH CLASS:
15, Brushing, Scrubbing, and General Cleaning, subclass 339 for brushing, scrubbing and general cleaning machines having a signal or indicator to indicate the condition of the machine or work.
34, Drying and Gas or Vapor Contact With Solids, subclass 89 for apparatus of that class combined with indicating or signaling means.
40, Card, Picture, or Sign Exhibiting, 463 for electrically actuated changeable exhibitors, such as the advertising display type and subclasses 541+ for illuminated signs having significant sign structure in addition to electric illumination. Advertising display elements arranged in matrix are in class (345) subclasses 55+.
43, Fishing, Trapping, and Vermin Destroying, subclass 16, 17, and 58 for the subject matter of that class combined with signals and indicators.
70, Locks, subclass 434 for locks combined with electric recorders for indicating the previous condition of the lock, and other appropriate subclasses for locks combined with electric signals.
73, Measuring and Testing, appropriate subclasses for testing devices which make a test of the Class 73 type (usually nonelectrical and nonchemical) and signal the result of said test by electrical means. Note particularly 23.2, 301, 304, 308, 313, 717+, 723+, 733+, and 753+.
81, Tools, subclass 479 for torque-responsive wrenches or screwdrivers having electrical means to indicate when a selected torque is exerted.
84, Music, subclass 405 for xylophones with electric action, subclass 407 for bell sets (carillons) with electric action and subclass 462 for electric devices responsive to playing of a musical instrument for recording the action of said instrument.
99, Foods and Beverages: Apparatus, subclass 285 for beverage infusers having signal means and subclasses 342+ for cookers having signal means.
100, Presses, subclass 99 for presses having electrical means to indicate the condition of the press or the material being pressed.
109, Safes, Bank Protection, or a Related Device, 38 for safes and analogous structures having alarm devices for signaling loss of integrity.
114, Ships, subclass 246 for indicators for locating the position of a towed vessel with respect to the towing vessel.
116, Signals and Indicators, see Lines With Other Classes and Within This Class, in the class definition for the line between the electrical signals in Class 340 and the mechanical signals in Class 116. Search appropriate subclasses of Class 116 for mechanical signals and indicators analogous to the electrical signals and indicators of Class 340. Search subclass 20 for helios:graphic signaling along a light ray.
118, Coating Apparatus, 712 for coating apparatus having a signal or indicator.
119, Animal Husbandry, 14.14 for milkers having a signal or indicator.
134, Cleaning and Liquid Contact With Solids, subclass 113 for cleaning or wetting devices having signals or indicators.
137, Fluid Handling, 551 for fluid handling equipment having signal or indicating means.
160, Flexible or Portable Closure, Partition, or Panel, subclass 10 for the subject matter of that class having signals or indicators.
169, Fire Extinguishers, 19 for fire extinguishing systems having automatically opened valves and subclass 23 for fire extinguishing systems having alarms which indicate some abnormal condition of the fire extinguishing system. The nominal combination of a fire extinguishing system, recited nonsignificantly, as by name only, and a significantly recited electric signaling system is classified in appropriate subclasses of Class 340, (for which see Subclass References to the Current Class above)
174, Electricity: Conductors and Insulators, subclass 11 for fluid-insulated conductors having means to indicate the condition of the fluid.
177, Weighing Scales, 45 for a weigher having an alarm or signal.
178, Telegraphy, appropriate subclasses for teles:graphic signaling. See the class definition of Class 178 for the line between Classes 178 and 340. The combination of a Class 340 system and a Class 178 system is classified in Class 340. in appropriate subclasses, see Subclass References to the Current Class above.
181, Acoustics, 101 for mechanical compressional wave devices and systems, such as those used in seismic
prospecting, subclasses 123+, for mechanical sound echo systems, and subclass 125 for mechanical sound location apparatus and methods.
182, Fire Escape, Ladder, or Scaffold, subclass 18 for a fire escape, ladder, or scaffold having an indicator, signal or alarm.
185, Motors: Spring, Weight, or Animal Powered, subclass 14, 36, and 44 for spring and weight motors having indicators to show the extent to which they are wound up or run down.
187, Elevator, Industrial Lift Truck, or Stationary Lift for Vehicle, appropriate subclasses for signalling means in combination or limited to use with elevator structure.
188, Brakes, appropriate subclasses for significantly claimed brakes or brake systems combined with signals.
194, Check-Actuated Control Mechanisms, 302 for coin controlled mechanisms having a signal to indicate the condition (e.g., counterfeit coin) of the mechanism.
198, Conveyors: Power-Driven, subclass 40 for conveyors having signaling means.
200, Electricity: Circuit Makers and Breakers, subclass 308 for switches having indicators to indicate the position or condition of the switch.
215, Bottles and Jars, 365 for receptacles having indicating means and subclasses 201+, 227, and 230 for closures having indicating means.
219, Electric Heating, subclass 109 for a current supply indicator (e.g., a recorder, etc.) to a metal heating (e.g., resistance heating, etc.) pressure bonding (e.g., resistance welding, etc.) apparatus, subclass 209 combined with a diverse-type electrical art device, subclass 248 for a heating device combined with a sole plate-type pressure application means (e.g., a flatiron, etc.) including a condition-responsive indicator, subclass 269 for an igniter-type resistive element indicating means, subclass 445.1 for an exposed planar support surface for material to be heated (e.g., hot plate, etc.) including an indicator, subclasses 446.1+ for an exposed planar support surface for material to be heated (e.g., hot plate, etc.) including a sensing means, subclass 487 for a heating device having a power supply and voltage or current regulation or current control means to control or regulate plural separate distinct heating resistance elements (i.e., one control system for all elements, etc.) selectively, sequentially, or alternately including indicator means, subclass 506 for a heating device having automatic regulating or control of power supply and voltage including signal or indicator means, subclass 667 for a condition responsive temperature load sensing power switching supply system for an inductive heating device,
subclass 714 for a remote control system for a microwave heating device, subclass 719 for a timer control system for a microwave heating device, or subclass 720 where a control system for a microwave heating device has a display or alarm.
221, Article Dispensing, 2 for article dispensers not otherwise classified having indicators or signals.
222, Dispensing, 23 for fluent material dispensing means having indicators or signals.
232, Deposit and Collection Receptacles, subclasses 34-37 for letter boxes having signals or indicators.
234, Selective Cutting (e.g., Punching), 4 for a typographical punching machine provided with means to indicate approach to and entry into the justification zone; subclasses 13+ and 22+, for a selective cutting machine with automatic control usually initiated by an indicator or detector of a given operating condition; subclasses 59+, for a pattern-controlled selective cutting machine which may be electrically operated.
235, Registers, subclass 61 for mechanical calculators, subclasses 400+ for ordnance control data calculators, subclasses 419+ for electromechanical or mechanical record controlled calculators, subclasses 435+ for coded record sensors, and subclasses 487+ for coded records adapted to be read by machine.
241, Solid Material Comminution or Disintegration, subclass 101.01 for the subject matter of that class having signals and indicators.
242, Winding, Tensioning, or Guiding, subclass 357, 472.0+, 479.9+, 484.8, 484.9+, 534+, 563+, and 912 for a detector, signal, or indicator associated with winding or unwinding an elongated material.
246, Railway Switches and Signals, for railway signaling and control systems. See the class definition of Class 246 for the line between Classes 246 and 340.
250, Radiant Energy, for signaling systems of the radiant energy type; 306 for methods and apparatus for inspecting solids or liquids by charged particles, subclasses 330+ for the detection of infrared patterns and the conversion of the pattern into a light image, subclasses 336.1+ for methods and apparatus to detect and indicate the intensity or frequency of invisible radiation or the testing of materials by detecting and indicating the change in invisible radiation caused by the material, and subclasses 200 to 239 for photocell light-responsive circuits and apparatus. (See Lines With Other Classes and Within This Class)
258, Railway Mail Delivery, subclass 2 for the subject
matter of that class (which includes delivery to and from airborne vehicles) having signaling features.
276, Typesetting, subclass 11 for typesetting machines having means for indicating the length of the line set.
291, Track Sanders, subclass 17 for track and vehicle sanding machines provided with alarms to indicate the operation thereof.
307, Electrical Transmission or Interconnection Systems, appropriate subclasses for the subject matter of that class having signals and indicators. Note that many of the systems of this class, while not having signals and indicators, have automatic controls which are analogous to signals.
312, Supports: Cabinet Structure, 234 for cabinets having indicators.
313, Electric Lamp and Discharge Devices, subclass 10 for electric space discharge devices, such as vacuum tubes, or electric lamps having temperature indicators.
314, Electric Lamp and Discharge Devices: Consumable Electrodes, subclass 9 for electric arc lamps having a signal or indicator.
315, Electric Lamp and Discharge Devices: Systems, 129 for electric gas discharge device systems or electric lamp systems having signals, indicators or alarms and subclasses 364+ for space discharge devices testing or lamp testing equipment having signals or indicators.
318, Electricity: Motive Power Systems, subclass 490 for electric motor systems having signals or indicators.
320, Electricity: Battery or Capacitor Charging or Discharging, appropriate subclass for a battery or capacitor charging or discharging circuit combined with an indicator.
322, Electricity: Single Generator Systems, subclass 99 for electric generator systems having signals or indicators.
324, Electricity: Measuring and Testing, appropriate subclasses for testing systems for making tests of electric properties having means to indicate the result of the test. Note 323 for testing systems for locating ore bodies having means to indicate the result of the test, and subclasses 76.11+ for meters for measuring a property of an electric current or voltage or combination thereof (e.g., power factor, watt-hours, phase angle frequency). Telemetering systems which utilize a meter as a portion thereof are in Class 340 subclasses 870.02+, but the meter subcombination, per se, is classified with the meters of Class 324. Telemetering systems which, by significantly claimed structure or circuit, indicate the result of an electrical test at a point remote from the point of measurement are
classified with the test in Class 324, as such telemetering systems are not of general utility, but are restricted to use in Class 324 measurements.
329, Demodulators, for demodulators of modulated intelligence including continuous waves (CW), and which furnish something more than the mere indication of the initiation of the signal.
331, Oscillators, appropriate subclasses, for electric oscillation generators of utility in the communication systems of Class 340. Class 331, subclass 64 for oscillator systems provided with an indicator, signal or alarm.
332, Modulators, subclass 118 and 150 for modulators having signals and indicators.
333, Wave Transmission Lines and Networks, for wave transmission systems wherein electromagnetic wave energy is guided or constrained by a propagation medium of appreciable electrical length as compared to the wavelength of the propagated energy. This class includes numerous networks and components useful in communications. Note particularly subclass 20 for wave-shaping networks of the passive type, subclasses 24+ for coupling networks including delay networks and filters, and subclasses 236+ for long lines having distributed electrical parameters, and subclasses 1+ for plural channel systems of these lines and networks.
336, Inductor Devices, subclass 45 for inductors having movable parts and means to indicate the position of the movable part.
338, Electrical Resistors, 13 and 68+ for variable resistors including rheostats and potentiometers.
341, Coded Data Generation or Conversion, appropriate subclasses for code conversion, transmission or generation.
342, Communications: Directive Radio Wave Systems and Devices (e.g., Radar, Radio Navigation) appropriate subclasses for signaling systems of the radio wave energy type. (See Lines With This Class and Within Other Classes.)
345, Computer Graphics Processing, Operator Interface Processing and Selective Visual Display Systems, 1 for plural display systems and 418+ for computer s:graphics processing.
346, Recorders, appropriate subclasses for signals or indicators which record, and subclass 16 and 17+ for recorders combined with signals and indicators.
348, Television, appropriate subclasses for television communication systems.
356, Optics: Measuring and Testing, for visible light type
testing and examination instruments particularly for light radar devices in 3, subclasses 43+ for optical pyrometers, subclasses 372+ for menstruation devices, subclass 388 for configuration comparison devices, subclass 402 for shade or color test devices, subclasses 213+ for photometers, and subclasses 237.1+ for flaw and imperfection devices.
358, Facsimile and Static Presentation Processing, appropriate subclasses for data processing for static presentation to printer, and facsimile communication systems.
360, Dynamic Magnetic Information Storage or Retrieval, appropriate subclass for read/write dynamic storage systems.
362, Illumination, appropriate subclasses for illuminating means which may serve as signalling means.
364, Electrical Computers and Data Processing Systems, 130 for generic data processing control systems; subclass 147 for programming methods or procedures; subclasses 400+ for particular application of data processing systems or calculating computers.
365, Static Information Storage and Retrieval, appropriate subclass for read/write static storage systems, 185.01 for floating gate memory storage (e.g., flash memory).
367, Communications, Electrical: Acoustic Wave Systems and Devices, for electrical communication systems in which the intelligence communicated is transmitted in part as acoustic wave energy.
368, Horology: Time Measuring Systems or Devices, 46 for electric systems which indicate time and for electric clocks.
370, Multiplex Communications, appropriate subclasses for multiplexing systems.
374, Thermal Measuring and Testing, 163 for a thermometer with an electrical heat sensor and a quantitative signalling arrangement.
377, Electrical Pulse Counters, Pulse Dividers, or Shift Registers: Circuits and Systems, 112 for electrical counters with display or indication.
380, Cryptography, subclasses 255-276 for a communication system using cryptography.
381, Electrical Audio Signal Processing and Systems, appropriate subclasses for one-way audio signal transmission and audio signal processing systems.
395, Information Processing System Organization, 80 for data processing of robot control systems.
396, Photography, 429 for a camera combined with diverse art devices.
400, Typewriting Machines, appropriate subclasses for typewriters having signals to indicate the condition or operation of the machine. Note particularly 70.
404, Road Structure, Process, or Apparatus, 9 for nonelectric roadway structure designed to direct traffic.
406, Conveyors: Fluid Current, 34 for conveyors having signals or indicators.
422, Chemical Apparatus and Process Disinfecting, Deodorizing, Preserving, or Sterilizing, 50 or 105+ for chemical apparatus having means to electrically signal a condition of said apparatus or the result of a chemical test.
429, Chemistry: Electrical Current Producing Apparatus, Product, and Process, 90 for battery having measuring, testing, or indicating means.
434, Education and Demonstration, 327 for educational appliances which have a question and hidden answer, some of which signal a correct answer and subclasses 112+ for machines by which a blind person can read printed material, said machine furnishing signals which are a coded representation of the printed material.
441, Buoys, Rafts, and Aquatic Devices, 6 for floating buoys utilized for marine navigation.
446, Amusement Devices: Toys, appropriate subclasses for various electric and magnetic toys which utilize electric signals, particularly subclass 142, 242, 454, and 484+.
505, Superconductor Technology: Apparatus, Material, Process, 150 for high temperature (T[subscrpt]c[end subscrpt] > 30 K) superconducting devices, and particularly subclasses 182+ for light responsive system or subclass 202 for electric communication system.
600, Surgery, 300 for electric diagnostic devices having signals or indicators.
702, Data Processing: Measuring, Calibrating, or Testing, appropriate subclasses for measuring, testing, or calibrating system having significant data processing.
704, Data Processing: Speech Signal Processing, Linguistics, Language Translation and Audio Compression/Decompression, 200 for artificial intelligence systems that process speech signals.
706, Data Processing: Intelligent Processing Systems and
Methods, various subclasses for artificial intelligence systems that represent, apply, and acquire knowledge.
708, Electrical Computers: Arithmetic Processing and Calculating, 1 for hybrid computers; subclasses 100+ for digital calculating computers, and subclasses 800+ for analog computers.
709, Electrical Computers and Digital Processing Systems: Multiple Computer or Process Coordinating, 200 for data transfer among multiple computer systems.
714, Error Detection/Correction and Fault Detection/Recovery, subclasses for apparatus and corresponding processes relating to generic error detection or correction, or fault detection or recovery.

Interrogation response:
This subclass is indented under 825. having an information containing device and an information source control device for querying the information containing device, with the expectation of an immediate reply.

SEE OR SEARCH THIS CLASS, SUBCLASS:
505 for interrogator-responder in a condition responsive indicating system with particular system function.
572.1-572.9, for condition responsive detecting a detectable device on a protected article.
825.26 and 825.27, for such subject matter for interrogation and display of stock prices.
825.28 and 825.29, for such subject matter for interrogation and display of space allocation information.
825.31-825.33, for transponders used for access control.
825.44-825.48, for two-way paging in selective communications.
870.28 and 870.29, for continuously variable indicating via radiant energy, and subclass 870.32 via mutual inductance.

SEE OR SEARCH CLASS:
235, Registers, subclasses 375-386 for systems controlled by data bearing records which may include interrogation response system or device.
342, Communications: Directive Radio Wave Systems and Devices (e.g., Radar, Radio Navigation), subclasses 42-51 for transponder system using radar.
455, Telecommunications, subclass 41 for near field communication and subclass 106 for modulation by absorption, shielding, or reflecting.

Contention avoidance:
This subclass is indented under 10.1. including means to enable an interrogation controller to receive responses from multiple information containing devices relatively error free.

SEE OR SEARCH CLASS:
370, Multiplex Communications, subclasses 229-240 for data flow congestion prevention or control in a multiplex communications network.

Interrogation signal detail:
This subclass is indented under 10.1. wherein an interrogation signal having designated characteristics is sent from the source controller.

Individual call:
This subclass is indented under 10.3. wherein the interrogation signal uniquely identifies a specific information containing device.

Group call:
This subclass is indented under 10.3. wherein the interrogation signal identifies a group of information containing devices.

Wake up (all call):
This subclass is indented under 10.3. wherein the specific interrogation signal initiates a response from all information containing devices within range.

Power up:
This subclass is indented under 10.3. wherein the interrogation signal provides energy to all information containing devices.

Response signal detail:
This subclass is indented under 10.1. wherein a specific response signal is sent from the information containing device.

Combination response:
This subclass is indented under 10.4. wherein the response signal is a composite signal including multiple type of information.

Identification only:
This subclass is indented under 10.4. wherein the response signal includes the unique identity of the information containing device.

Additional control:
This subclass is indented under 10.1. wherein a subsequent operation is performed in response to the interrogation
signal.

Programming (e.g., read/write):
This subclass is indented under 10.5. wherein the subsequent operation is the writing of data into the information containing device.

ID code:
This subclass is indented under 10.51. wherein the data written is a unique identification of the information containing device.

Printout or display:
This subclass is indented under 10.1. including an information presenting device for forming a permanent or semipermanent record of the information.

This subclass is indented under the class definition. Subject matter having means for comparing signals or information in digital form to determine which is the greater, the lesser, or whether they are numerically equal.
(1) Note. The digital signals are not limited to any particular radix, and may be, for example, binary, decimal, etc.

SEE OR SEARCH THIS CLASS, SUBCLASS:
825.3 for comparator systems.

SEE OR SEARCH CLASS:
250, Radiant Energy, 568 for a photocell and a coded record wherein the coded information consists of discrete identical indicia and is represented by the relative positional locations of the indicia on the record.

SYSTEMS:
This subclass is indented under the class definition. Subject matter relating to a system including transmitter and receiver for signaling and/or indicating.
(1) Note. This is the miscellaneous subclass for systems of signaling and/or indicating and their subcombinations, not elsewhere provided for.
(2) Note. The terms signaling and indicating each denote production of a humanly perceptible signal.
(3) Note. Consult the search notes to the class definitions for some of the numerous other classes which contain signaling or indicating systems.

SEE OR SEARCH THIS CLASS, SUBCLASS:
500 for condition responsible alarm signaling.
815.4 for a visual indicator for signaling.
825 for selective signaling.

SEE OR SEARCH CLASS:
345, Computer Graphics Processing, Operator Interface Processing, and Selective Visual Display Systems, for signaling with a selective display.

Network signaling:
This subclass is indented under subclass 286.01. Subject matter consisting of an organization of stations with a capability for intercommunication although not necessarily on the same channel.

SEE OR SEARCH THIS CLASS, SUBCLASS:
825.52 for this subject matter further including station addressing.

SEE OR SEARCH CLASS:
370, Multiplex Communications, appropriate subclasses for network of stations including multiplexed communications therebetween.
379, Telephonic Communications, appropriate subclasses for signaling specific to a telephone systems.

Speaking tube including circuit:
This subclass is indented under subclass 286.02. Subject matter in which a tube-shaped device mechanically transmits and/or amplifies sound in combination with a diverse electrical circuit.

SEE OR SEARCH CLASS:
181, Acoustics, subclass .5 for a speaking tube, per se; e.g., without diverse circuitry.

Manual alarm telegraph; e.g., other than signal box type:
This subclass is indented under subclass 286.01. Subject matter wherein the system employs interruptions and/or polarity changes of direct current for the transmission of alarm signals that have been keyed.
(1) Note. This is the residual subclass for manual alarm telegraphs systems not elsewhere classified.
(2) Note. Manual alarm telegraphs are also called alarm telegraph systems.
(3) Note. The term "Telegraph system" should be distinguished from the subject matter of Class 178, Telegraphy, which subject matter permits signaling of a message of arbitrary content.

SEE OR SEARCH THIS CLASS, SUBCLASS:
287 for this subject matter when the transmitter is of the signal box type.
500 for condition responsive alarm devices.

SEE OR SEARCH CLASS:
178, Telegraphy, 2 for Telegraph systems including information signal of arbitrary contents.

Fire:
This subclass is indented under subclass 286.04. Subject matter in which the alarm is actuated to indicate the occurrence of a fire.

SEE OR SEARCH THIS CLASS, SUBCLASS:
287 for a signal box type fire alarm.
577 for a flame actuated fire alarm.
628 for a smoke actuated fire alarm.

Call station:
This subclass is indented under subclass 286.01. Subject matter in which a transceiver connects rooms or other places from which a signal or call is sent and/or received to the central or main location.

Hospital:
This subclass is indented under subclass 286.06. Subject matter located at an institution where the sick or injured are given medical care.

Hotel:
This subclass is indented under subclass 286.06. Subject matter located at an establishment that provides lodging.

Restaurant:
This subclass is indented under subclass 286.06. Subject matter located at a public eating place.

Annunciator:
This subclass is indented under subclass 286.01. Subject matter in which an electrically controlled signal board or indicator indicates the condition that exists or has existed in an associated circuit.

SEE OR SEARCH THIS CLASS, SUBCLASS:
815.47 for switchboard or panel type visual indicator for signaling and subclasses 815.01+ for group drop annunciators.

SEE OR SEARCH CLASS:
116, Signals and Indicators, appropriate subclasses for nonelectric signaling.

Drop annunciator:
This subclass is indented under subclass 286.11. Subject matter in which the annunciator consists of a number of pilot lights or drops, each one indicating an associated circuit condition.

SEE OR SEARCH THIS CLASS, SUBCLASS:
815.47 for switchboard or panel type visual indicator for signaling.
815.79 for pointer annunciator.
815.81 for group drop annunciators.
815.85 for self restoring type annunciator.
815.9 for electromagnet releases latch.

Mimic:
This subclass is indented under subclass 286.01. Subject matter in which the signaling or indicating copies or imitates by a spatial distribution that which is being indicated upon a single indicating surface.
(1) Note. This surface is usually a display.

SEE OR SEARCH THIS CLASS, SUBCLASS:
525 for this subject matter in a condition responsive signaling system.

SEE OR SEARCH CLASS:
345, Computer Graphics Processing, Operator Interface Processing, and Selective Visual Display Systems, 168 for this subject matter in a selective display system.

Mapping:
This subclass is indented under subclass 286.13. Subject matter in which the signaling or indicating forms representation of the whole or a part of an area.

This subclass is indented under subclass 286. Subject matter in which the transmitter is of the signal box type.
(1) Note. The signal box may be of the type which is used in fire alarms, police, district telegraph, messenger box or the like systems. The transmitter usually is a code transmitter.

SEE OR SEARCH THIS CLASS, SUBCLASS:
534 for code transmitter systems which are automatically responsive to a condition.

SEE OR SEARCH CLASS:
341, Coded Data Generation or Conversion, 20 and 173+ for a pulse code transmitter.

This subclass is indented under subclass 287. Subject matter combined with some other type of subject matter.
(1) Note. The signaling system, for example, may be combined with an electric light system whose conductors are used as the transmission medium for the signaling system.

SEE OR SEARCH CLASS:
178, Telegraphy, subclass 49 for telegraph systems combined with other types of electric systems.

This subclass is indented under subclass 288. Subject matter combined with a fire extinguisher.

SEE OR SEARCH CLASS:
169, Fire Extinguishers, appropriate subclasses, particularly subclass 23 for combinations of extinguishers as sprinkling systems with mere electric alarms other than code signals of the signal box transmission type.

This subclass is indented under subclass 288. Subject matter in which the signaling system is combined with means to control apparatus at the fire station.
(1) Note. The system may, for example, automatically open a door at the engine house when the fire alarm rings.

This subclass is indented under subclass 287. Subject matter having means for repeating signals one or more times or for repeating signals from one line or station to another line or station.
(1) Note. The signal may be repeated, for example, from the call box circuit into several circuits extending to separate fire houses.

SEE OR SEARCH CLASS:
178, Telegraphy, 70 for repeaters utilized in telegraphy.

This subclass is indented under subclass 287. Subject matter provided with means for maintaining the circuit in operable condition so as to permit sending signals at all times in spite of one or more breaks in the wires and signal box systems provided with means for giving an alarm when an abnormal condition in a circuit, which would prevent normal use, develops.

SEE OR SEARCH CLASS:
178, Telegraphy, subclass 69 for line clearance and circuit maintenance systems utilized in telegraphy.

This subclass is indented under subclass 287. Subject matter provided with means at the signal box for transmitting one or more of a variety of signals under the control of the operator.

SEE OR SEARCH CLASS:
341, Coded Data Generation or Conversion, 20 and 173+ for a pulse code transmitter..

This subclass is indented under subclass 293. Subject matter provided with a dial selector for selecting the variable signal desired.

This subclass is indented under subclass 287. Subject matter provided with means for preventing the transmission of signals from any other box or other signals from the same box while any signal is being transmitted therefrom and until such signal is completed.

This subclass is indented under subclass 295. Subject matter provided with means to obstruct the entrance of the key which is used to operate the signal box, said means operating to prevent insertion of the key only during the transmission of a signal sequence.

This subclass is indented under subclass 287. Subject matter provided with means to exhibit indications at the signal box from which the signals are transmitted, so that said box also acts as a receiver.
(1) Note. The signal box, when operated, for example, may produce a preliminary signal of the audible type at the box to discourage would be pranksters from turning in a false alarm.

This subclass is indented under subclass 297. Subject matter having means to send an answer-back signal to notify the operator that the transmitted signal has been received.

This subclass is indented under subclass 297. Subject matter in which the signal at the box is operated simultaneously by the transmitted signal.

This subclass is indented under subclass 297. Subject matter in which the signal at the box is a lamp.
(1) Note. The lamp may, for example, be used to notify a policeman on his beat to call in.

This subclass is indented under subclass 287. Subject matter in which the signal box in actuated by a movable key.
(1) Note. The key may, for example, be attached to the box by means of a chain, or the key may be in the custody of the person who turns in the alarm, who must surrender the key to box mechanism before he can turn the alarm in, so that his identity may be made known.

This subclass is indented under subclass 301. Subject matter in which the key is normally housed by a frangible closure, which must be broken in order to obtain the key for operation of the box.

This subclass is indented under subclass 287. Subject matter provided with a frangible closure which must be broken in order to send a signal.

SEE OR SEARCH THIS CLASS, SUBCLASS:
302 for this subject matter where the frangible closure encloses a movable key, which key is used to transmit the signal.

This subclass is indented under subclass 287. Subject matter provided with means for combating false alarms.
(1) Note. The signal box may, for example, be provided with means for detaining, as by hand-cuffing means, the person who sends in an alarm.

SEE OR SEARCH THIS CLASS, SUBCLASS:
301 for signal box systems where the person turning in the alarm must surrender an individual key to the signal box
mechanism before he can send the alarm.

This subclass is indented under subclass 287. Subject matter in which the signal box is actuated by a local circuit separate from the main circuit.

This subclass is indented under subclass 305. Subject matter in which the signal box is provided with a local circuit for use by watchmen.

This subclass is indented under subclass 287. Subject matter consisting of a transmitter utilized in signal box systems.

SEE OR SEARCH CLASS:
341, Coded Data Generation or Conversion, 20 and 173+ for a pulse code transmitter.

This subclass is indented under subclass 307. Subject matter in which the signal is sent automatically when the door of the signal box is opened.

This subclass is indented under subclass 307. Subject matter having a rotary make and break wheel.

SEE OR SEARCH CLASS:
341, Coded Data Generation or Conversion, subclass 16 and 17 for a pulse code transmitter having a rotary make and break wheel.

Timer controlled:
This subclass is indented under subclass 286.01. Subject matter in which the system includes means whereby the communication is brought about after a predetermined time lapse or is continued for a predetermined time following initiation.

SEE OR SEARCH CLASS:
219, Electric Heating, subclass 719 for a timer control system for a microwave heating device.
368, Horology: Time Measuring Systems or Devices, 19 for a mechanical clock with an electric alarm and subclasses 108+ for an electric alarm clock.

This subclass is indented under subclass 309.15. Subject matter combined with means other than partially or wholly electrical means for conveying information or intelligence.

This subclass is indented under subclass 309.15. Subject matter including an additional means, not under the control of the timer, for conveying information or intelligence.

This subclass is indented under subclass 309.15. Subject matter including a plurality of indicators selectively or sequentially controlled by the timer.

This subclass is indented under subclass 309.4. Subject matter including a manually actuated means which has no utility in the operation involving the timer but may be utilized for controlling one or more of the indicators independently of the timer.

This subclass is indented under subclass 309.15. Subject matter in which the communication system includes two circuit maker-breakers in series, both of which must be closed in order for the information or intelligence to be transmitted, and both of the circuit maker-breakers being under the control of the timer.

Signal over power line:
This subclass is indented under subclass 286.01. Subject matter wherein communication signals are sent from one point to another in a system by means of an existing power line in the system.
(1) Note. The system may be an electric light system over whose conducters the signals are sent.
(2) Note. The information signal may be an address or a code signal.

SEE OR SEARCH THIS CLASS, SUBCLASS:
288 for this subject matter where the signal system is a signal box system.
320 for signaling systems in which the electric signal is sent along a fluid conduit.

SEE OR SEARCH CLASS:
455, Telecommunications, subclass 3.3 for a radio communication system combined with a power distribution network, and subclass 270 for a radio receiver using a power line as a wave collector.

Modulation technique:
This subclass is indented under subclass 310.01. Subject matter including details of technique for impressing a signal onto a carrier waveform for transmission over a power line.
(1) Note. The carrier can be a direct current or an alternating current.

Noise reduction (e.g., filtering):
This subclass is indented under subclass 310.01. Subject matter wherein a circuit is provided to compensate for signal defects.

Zero crossing:
This subclass is indented under subclass 310.03. Subject matter including means to extract information from its carrier wave at a region close to the zero crossing point of the carrier wave.

Impedance matching (e.g., Y-match or delta match):
This subclass is indented under subclass 310.01. Subject matter wherein a circuit is provided to make the impedance of a line terminal equal to the impedance of a circuit to which it is connected in order to achieve optimum signal transfer.

SEE OR SEARCH CLASS:
333, Wave Transmission Lines and Networks, subclass 17.3, 32+, and 124+ for impedance matching without communication.

Bidirectional (e.g., with transceiver):
This subclass is indented under subclass 310.01. Subject matter including at least two communicating terminals which can both transmit and receive signals.

With inductive coupling (e.g., transformer or torroid):
This subclass is indented under subclass 310.01. Subject matter wherein information on the power line is transferred to or from a terminal through a mutual or common inductance.

SEE OR SEARCH CLASS:
333, Wave Transmission Lines and Networks, 24 for coupling networks which may include inductive coupling.

With coupling plug:
This subclass is indented under subclass 310.01. Subject matter wherein information on the power line is transferred to or from a terminal through a connector.

Paging:
This subclass is indented under subclass 286.01. Subject matter wherein there is a humanly perceptible signal which is used to summon an individual.
(1) Note. The subject matter of this subclass is limited to nonselective paging.

SEE OR SEARCH THIS CLASS, SUBCLASS:
825.44 for selective paging.

This subclass is indented under subclass 286.02. Subject matter having means to send an interrogation from one station to another and having means to send the answer to said interrogation back from said second station to said first station.

SEE OR SEARCH THIS CLASS, SUBCLASS:
10.1-10.6, for selective systems for automatically and selectively answering interrogations.

This subclass is indented under subclass 313. Subject matter having means to sound an alarm if the answer to the interrogation is improper.

This subclass is indented under subclass 286.01. Subject matter having selsyn-type transmitters and receivers.

SEE OR SEARCH THIS CLASS, SUBCLASS:
870.34 for this subject matter in telemetering systems.

SEE OR SEARCH CLASS:
318, Electricity: Motive Power Systems, 690 for self-synchronous electric motor systems.

This subclass is indented under subclass 286.02. Subject matter in which the receiver is provided with means which are unbalanced by the transmitter signal and is provided with means for rebalancing said means.

SEE OR SEARCH CLASS:
318, Electricity: Motive Power Systems, 638 for electric motor systems controlled by a self-balancing network.

This subclass is indented under subclass 316. Subject matter in which the unbalanced means at the receiver is automatically rebalanced.

SEE OR SEARCH THIS CLASS, SUBCLASS:
870.43 for similar subject matter utilized in telemetering systems.

This subclass is indented under subclass 286. Subject matter having synchronous distributers at both the transmitter and receiver.

SEE OR SEARCH THIS CLASS, SUBCLASS:
870.13 for similar subject matter utilized in telemetering systems.

SEE OR SEARCH CLASS:
370, Multiplex Communications, 304 for multiplexing systems which include a synchronous distributor at both the transmitter and receiver.

This subclass is indented under subclass 286.01. Subject matter in which the receiver has plural electromagnets or plural motors.

SEE OR SEARCH THIS CLASS, SUBCLASS:
870.05 for similar subject matter utilized in telemetering systems.

This subclass is indented under subclass 286.01. Subject matter in which the electric signal is transmitted along a fluid conduit.
(1) Note. The fluid conduit may, for example, be a fire hose, so that the firemen may be able to communicate back from the nozzle to the engine pumper.

SEE OR SEARCH CLASS:
174, Electricity: Conductors and Insulators, 8 and 47 for fluid conduits combined with electrical conductors.

This subclass is indented under subclass 286.01. Subject matter which is portable and self-contained.
(1) Note. This subclass includes, for example, movie ushers' flashlights which have means for signaling.

SEE OR SEARCH CLASS:
362, Illumination, 157 for battery flashlights of general utility.

This subclass is indented under subclass 286.01. Subject matter in which the system has means to cancel any indications after a fixed time.

This subclass is indented under subclass 286.01. Subject matter for reporting the status of a game.

SEE OR SEARCH CLASS:
116, Signals and Indicators, 222 for mechanical game reporting devices.
273, Amusement Devices: Games, appropriate subclasses for games in combination with game reporting devices.
473, Amusement Devices: Games, and its incorporated class (273, Amusement Devices, Games), for a game device or apparatus with a game reporting device.

This subclass is indented under subclass 286.01. Subject matter in which a single variation indication is given at plural points or in plural manners.
(1) Note. The indication may, for example, be given by an electric light signal and also by an electric bell signal, so that the bell rings when the light flashes.

This subclass is indented under subclass 326. Subject matter provided with means to cut off a sound signal.
(1) Note. The sound signal, for example, may be cut off while the light signal continues to flash, or one sound signal may be cut off while the second one continues to sound.

This subclass is indented under subclass 286.01. Subject matter having an audible signal.

SEE OR SEARCH THIS CLASS, SUBCLASS:
384 for audible signals, per se.

This subclass is indented under subclass 328. Subject matter in which the audible signal operates intermittently.

This subclass is indented under subclass 286.01. Subject matter for signaling whether a person is "in" or "out".
(1) Note. A door bell button may, for example, cause an "out" sign to flash instead of causing the bell to ring.

This subclass is indented under subclass 286.01. Subject matter having a periodic or flashing signal.

SEE OR SEARCH THIS CLASS, SUBCLASS:
329 for this subject matter where the signal indicator is audible.

This subclass is indented under subclass 286.01. Subject matter having signal lights.

This subclass is indented under subclass 286.01. Subject matter having significantly recited or significant power supply systems.
(1) Note. The system, for example, may be provided with means to substitute an auxiliary source of power if the regular source fails.

SEE OR SEARCH CLASS:
307, Electrical Transmission or Interconnection Systems, 64 for emergency power systems of general application.

AUDIBLE INDICATION:
This subclass is indented under the class definition. Subject matter comprising signalling means for producing an acoustic wave as a signalling indication.

SEE OR SEARCH CLASS:
116, Signals and Indicators, appropriate subclasses for nonelectrical audible indicators.
178, Telegraphy, subclass 99.1 for private sounders (e.g.,
acoustically shielded).
219, Electric Heating, subclass 248 for a heating device combined with a sole plate-type pressure application means (e.g., a flatiron, etc.) including a condition-responsive indicator, subclass 269 for an igniter-type resistive element indicating means, or subclass 720 where a control system for a microwave heating device has a display or alarm.
221, Article Dispensing, subclass 3 for article dispensing with audible recorder, register, indicator, signal, or exhibitor.
222, Dispensing, subclass 39 for dispensing with audible recorder, register, indicator, signal, or exhibitor.
367, Communication, Electrical: Acoustic Wave Systems and Devices, 140 for acoustic signalling devices for use in electro-acoustic communication.
368, Horology: Time Measuring Systems or Devices, 243 for signalling means.
704, Data Processing: Speech Signal Processing, Linguistics, Language Translation, and Audio Compression/Decompression, 231 for speech analysis (e.g., phoneme recognition) and subclasses 258+ for speech synthesis.

Ultrasonic pest control:
This subclass is indented under subclass 384.1. Subject matter wherein the audible signalling means includes a source for generating electrical signals within an ultrasonic frequency range and a transducer means for converting the electrical signals into an acoustic wave to repel unwanted animals.

SEE OR SEARCH CLASS:
43, Fishing, Trapping, and Vermin Destroying, appropriate subclasses for similar subject matter wherein the animal is destroyed or at least injured.
116, Signals and Indicators, subclass 22 for nonelectrical animal frightening device.
367, Communications, Electrical: Acoustic Wave Systems or Devices, subclass 139 for animal control.

Simulation:
This subclass is indented under subclass 384.1. Subject matter wherein the produced audible sounds are imitative sounds.
(1) Note. This subclass, includes, for example, audible signalling means for producing an imitative representation of sounds emitted by animals, engines, ship propellers, vehicles, children's toys, etc.

SEE OR SEARCH CLASS:
446, Amusement Devices: Toys, 397 for sounding amusement devices.

Electronic siren (e.g., wail tone or yelp tone warning device):
This subclass is indented under subclass 384.1. Subject matter wherein the audible signalling means includes a source for generating audio frequency electrical signals having a rising and falling pitch and a transducer for converting the signals into the produced audible sounds.

SEE OR SEARCH THIS CLASS, SUBCLASS:
404.1 for pneumatic siren sound producer.

SEE OR SEARCH CLASS:
116, Signals and Indicators, subclass 147 for nonelectrical siren.

With computer element:
This subclass is indented under subclass 384.1. Subject matter wherein the audible signalling means comprises a keyboard, memory means, or computer means connected to a transducer means for inputting, storing, or processing information representing or relating to the produced sounds outputted by the transducer means.

SEE OR SEARCH CLASS:
84, Music, 602 for electrical musical tone generator instrument with digital memory circuit.

Piezoelectric:
This subclass is indented under subclass 384.1. Subject matter wherein the audible signalling means is provided with a vibrator device for converting energized electrical signals into audible sounds in such a manner that the operation of the device depends on the interaction between electric charge of the energized electrical signals and the deformation or mechanical stress property of a crystal or ceramic element incorporated into the device.

SEE OR SEARCH CLASS:
84, Music, subclass 730 for electrical musical tone generator instrument with piezoelectric transducer.
367, Communications, Electrical: Acoustic Wave Systems and Devices, subclass 180 for piezoelectric receivers and subclass 155 for underwater type piezoelectric transducer array.
381, Electrical Audio Signal Processing Systems and Devices, subclass 190 for electrostrictive, magnetostrictive, or piezoelectric electro-acoustic audio transducer.

Electronic:
Subject matter under 384.1 having circuitry comprising at least a signal generator for generating an audio frequency electrical signal and a transducer means for converting the signal into audible sounds.
(1) Note. The circuitry may include other devices or components such as an amplifier, filter, switching means, feedback for affecting the generation of the electrical signals or the outputted sounds.

Timing:
This subclass is indented under subclass 384.7. Subject matter comprising a clock or timing means for producing the audible sounds at a repetitive rate or for controlling the start or the duration or the effect of the produced sounds.

Plural generators:
This subclass is indented under subclass 384.7. Subject matter comprising a plurality of oscillators for generating audio frequency signals at different operating frequencies or means for producing multi-tone audible sounds.

With sound transducer details:
This subclass is indented under subclass 384.7. Subject matter including at least a structural element of the sound transducer.
(1) Note. The structural element includes, for example, coil, core, diaphragm, etc. or supports therefor.

SEE OR SEARCH CLASS:
381, Electrical Audio Signal Processing Systems and Devices, 150 for nonindicating Electro Acoustic Audio Transducer.

Explosive:
This subclass is indented under subclass 384.1. Subject matter having means to produce a sharp, loud sound by a violent and sudden release of confined energy.

SEE OR SEARCH CLASS:
43, Fishing, Trapping, and Vermin Destroying, subclass 84 for explosive traps.
102, Ammunition and Explosives, appropriate subclasses for explosive devices in general.
116, Signals and Indicators, subclass 105 for nonelectrical ignition control explosive alarm.

Weatherproofing:
This subclass is indented under subclass 384.1. Subject matter provided with means for inclosing the audible signalling device to protect it from moisture, insects, or
other unwanted substances.
(1) Note. Watertight housing, sealed casing, etc., are included in this subclass.

SEE OR SEARCH CLASS:
219, Electric Heating, subclass 209 combined with a diverse-type electrical art device.

Diaphragm (e.g., horn or buzzer):
This subclass is indented under subclass 384.1. Subject matter wherein the audible sounds are produced by the vibration of an actuated flexible membrane.

SEE OR SEARCH CLASS:
116, Signals and Indicators, 142 for nonelectrical diaphragm horns, and subclass 59 for vehicle-energy actuated diaphragm horns.
381, Electrical Audio Signal Processing Systems and Device, 112 and subclasses 355+ for speaker, per se.

Alternating current:
This subclass is indented under subclass 388.1. Subject matter wherein the vibration of the diaphragm is caused by a current that changes the polarity with time in such a manner that the current reaches maximum in one direction, decreases to zero, reverses itself, and reaches minimum in the opposite direction.

SEE OR SEARCH THIS CLASS, SUBCLASS:
401.1 for alternating current used in percussion type sound producers.

With auxiliary flexible membrane:
This subclass is indented under subclass 388.1. Subject matter wherein the sounds are produced by the vibration of at least two diaphragms or by the vibration of a diaphragm and a resonator disc or plate secured to the diaphragm.
(1) Note. The two diaphragms are arranged in closely spaced parallel planes or in orthogonal planes.

SEE OR SEARCH CLASS:
116, Signals and Indicators, subclass 145 for nonelectrical parallel diaphragms.

With resonance chamber:
This subclass is indented under subclass 388.1. Subject matter provided with an air space or volume adapted to vibrate at a specific tuned frequency to amplify the produced sounds.

Armature support:
This subclass is indented under subclass 388.1. Subject matter including means for pivotally mounting or holding a movable part operated by an electromagnet to transmit its movement to the diaphragm for producing sounds.
(1) Note. This subclass includes, the bridge the plate, the frame, and the arm by which the armature is secured or supported.

SEE OR SEARCH THIS CLASS, SUBCLASS:
397.1 for armature support of percussion type sound producers.

Having spring:
This subclass is indented under subclass 388.5. Subject matter wherein the means for pivotally mounting or holding a movable part comprises a resilient member for supporting the armature or for restoring the armature to a normal position.

Interrupter:
This subclass is indented under subclass 388.1. Subject matter including means for controlling the flow of current into an electromagnet thereby operating a movable part to vibrate the diaphragm.

SEE OR SEARCH THIS CLASS, SUBCLASS:
397.3 for interrupter of percussion-type sound producers.

Having spring:
This subclass is indented under subclass 388.7. Subject matter wherein the interrupter comprises a resilient contact member or is supported by a resilient member.

Rotary actuator:
This subclass is indented under subclass 388.1. Subject matter comprising a driving mechanism operated by an electric motor to move in a circular motion for mechanically agitating the diaphragm.

SEE OR SEARCH CLASS:
116, Signals and Indicators, 143 for nonelectrical rotary striker diaphragm horns.

Having spring:
This subclass is indented under subclass 390.1. Subject matter wherein the driving mechanism comprises a resilient member for holding a driving shaft in a desired position by exerting a thrust force upon the shaft or for retracting the means for agitating the diaphragm.

Housing or mounting:
This subclass is indented under subclass 388.1. Subject matter comprising means for supporting or enclosing the audible signalling device.
(1) Note. This subclass includes supports for the diaphragm.

SEE OR SEARCH THIS CLASS, SUBCLASS:
396.1 for housing or mounting of percussion type sound producers.

Percussion-type sound producer (e.g., signal chimes or bells):
This subclass is indented under subclass 384.1. Subject matter having means to strike one element against another in order to produce the audible sounds.

SEE OR SEARCH THIS CLASS, SUBCLASS:
388.1 for this subject matter in which one of the elements is a diaphragm.

SEE OR SEARCH CLASS:
84, Music, 402 and 411+ for similar subject matter utilized in music.
116, Signals and Indicators, subclass 60 for vehicle-energy actuated bells, subclasses 148+ for nonelectrical bells, and subclass 25 for nonelectrical periodic bells.

Rotary actuator:
This subclass is indented under subclass 392.1. Subject matter comprising a driving mechanism operated by an electric motor to move in a circular motion to actuate the striking means.

Volume control:
This subclass is indented under subclass 392.1. Subject matter comprises means for regulating the loudness of the produced audible sounds.

Tubular sound producer (e.g., signal chimes):
This subclass is indented under subclass 392.1. Subject matter wherein the striking means hits a cylindrical body for producing the audible sounds.

Resonator (e.g., signal chimes):
This subclass is indented under subclass 392.1. Subject matter wherein the striking means hits a vibrating member associated with a tuned air chamber to emit a desired tone.

Plural armatures:
This subclass is indented under subclass 392.1. Subject matter comprising at least two movable elements attracted by one or more electromagnets for actuating the striking means for generating the audible sounds.

Battery operated:
This subclass is indented under subclass 392.1. Subject matter comprising a battery for energizing the striking means.

SEE OR SEARCH CLASS:
362, Illumination, 157 for flashlights having an unitary battery.

Pushbutton:
This subclass is indented under subclass 392.1. Subject matter in which a manually actuated device must be depressed to operate the striking means for generating the audible sounds.

Including timer:
This subclass is indented under subclass 392.1. Subject matter including a timing mechanism for controlling the timing of the strokes produced by the striking means.

Suspended (e.g., locomotive bell):
This subclass is indented under subclass 392.1. Subject matter including means for hanging the sound producer.

Housing or mounting:
This subclass is indented under subclass 392.1. Subject matter comprising means for enclosing or supporting the sound producing device.

SEE OR SEARCH THIS CLASS, SUBCLASS:
391.1 for housing or mounting of diaphragm sound producers.

Armature support:
This subclass is indented under subclass 392.1. Subject matter comprising means for pivotally holding or mounting a movable part which oscillates when the coils of the audible signalling means are energized by a current to reciprocate the striking means.
(1) Note. This subclass includes, for example, the bridge, the plate, the frame, the arm, or the yoke by which the armature is secured or supported.

SEE OR SEARCH THIS CLASS, SUBCLASS:
388.5 for armature support of diaphragm sound producers.

Having spring:
This subclass is indented under subclass 397.1. Subject
matter comprising a resilient member for carrying the armature, for restoring the armature to a normal position or for supplementing the effect of the current to move the armature.

Interrupter:
This subclass is indented under subclass 392.1. Subject matter including means for controlling the flow of current into an electromagnet to cause one element to strike against the other repeatedly.

SEE OR SEARCH THIS CLASS, SUBCLASS:
388.8 for interrupter of diaphragm sound producers.

Having spring:
This subclass is indented under subclass 397.3. Subject matter wherein means for controlling the flow of current includes a resilient contact member or is supported by a resilient member.

Polarized:
This subclass is indented under subclass 392.1. Subject matter wherein the striking means is electromagnetically operated and comprises a permanent magnet operatively causing the reciprocating of the armature.
(1) Note. This subclass includes, for example, a permanent magnet for magnetizing the armature, thereby creating permanent magnetic flux in the air gaps between the ends of the armature and the cores; current sent through the coils, produces a flux which adds to or subtracts from the permanent magnetic flux in the air gaps causing the armature to attract or repulse from two poles of the coils thereby causing the movement of the armature to reciprocate the striking mechanism; successive reversal of current in the coil terminal changes the direction of magnetism in the air gaps and thereby causing the armature to move up and down.

Nonelectrical driving means (e.g., spring or weight):
This subclass is indented under subclass 392.1. Subject matter wherein the striking means is driven by gravitational or stored mechanical energy.

With electromagnetic control:
This subclass is indented under subclass 398.1. Subject matter having an armature operated by an electromagnet to restrict or release the striking means.

Including circuit breaker:
This subclass is indented under subclass 398.2. Subject matter comprising an electric circuit having switch means for controlling the energization of the electromagnet.

Alternating current:
This subclass is indented under subclass 392.1. Subject matter in which striking means is operated by a current that changes polarity with time in such a manner that the current reaches maximum in one direction, decreases to zero, reverses itself, and reaches minimum in the opposite direction.

SEE OR SEARCH THIS CLASS, SUBCLASS:
388.2 for alternating current used in diaphragm sound producers.

Pneumatic-type sound producer (e.g., whistle or siren):
This subclass is indented under subclass 384.1. Subject matter wherein the signalling means is operated by the flowing of air or other gaseous stream to produce the audible sounds.

SEE OR SEARCH THIS CLASS, SUBCLASS:
815.72 for diverse indications having a pneumatic-type indication.

SEE OR SEARCH CLASS:
251, Valves and Valve Actuation, 129.01 for electrically actuated valve.

Rotary actuator:
This subclass is indented under subclass 404.1. Subject matter comprising an electric motor for actuating a driving mechanism in a circular motion to produce the audible sounds.

With valve:
This subclass is indented under subclass 404.1. Subject matter comprising means for regulating the flow of air or other gaseous stream thereby controlling the effect of the produced sounds.

TACTUAL INDICATION:
This subclass is indented under the class definition. Subject matter comprising means for producing an indication signal perceptible by the sense of touch.
(1) Note. The sense of touch is of human or animal.

SEE OR SEARCH CLASS:
116, Signals and Indicators, subclass 205 for nonelectrical indicators by touch.
345, Computer Graphics Processing, Operator Interface Processing, and Selective Visual Display Systems, 173 for touch panel used as input device of selective display systems.
901, Robots, subclass 32 for tactile sensor.

With input means (e.g., keyboard):
This subclass is indented under subclass 407.1. Subject matter combined with a manually actuated device to enter control or information data.
(1) Note. The manually actuated device includes, for example, a keyboard which may not, however, be the means for producing the indication itself.

SEE OR SEARCH CLASS:
341, Coded Data Generation or Conversion, 22 for electronic keyboard or keypad, per se.
345, Computer Graphics Processing, Operator Interface Processing, and Selective Visual Display Systems, 168 for keyboard as input device for providing selective electrical control in selective display systems.

REPEATER IN UNSPECIFIED TYPE COMMUNICATIONS LINE OR CHANNEL (E.G., RELAY STATION):
This subclass is indented under the class definition. Subject matter comprising a generically recited transmission path (e.g., telecommunications or communications line) having signal retransmitting or amplifying equipment in the path.
(1) Note. This subclass is directed to such subject matter in which the line is not identifiable as a particular communication line (e.g., telephone, telegraph).

SEE OR SEARCH CLASS:
178, Telegraphy, 70 for a telegraph repeater.
330, Amplifiers, appropriate subclasses for an amplifier.
370, Multiplex Communications, subclass 274, 279, 293, 315+, 492, and 501+ for repeaters used in multiplex communications.
375, Pulse or Digital Communications, 211 for a pulse or digital signal repeater.
379, Telephonic Communications, 338 for a telephone repeater.
455, Telecommunications, 7 for a carrier wave repeater.

Power control:
This subclass is indented under subclass 425.1. Subject matter comprising means for controlling power supplied to the repeater.

LAND VEHICLE ALARMS OR INDICATORS:
This subclass is indented under the class definition. Subject matter including systems or devices with an alarming or indicating function mounted on, or carried within, a land vehicle.

SEE OR SEARCH THIS CLASS, SUBCLASS:
500 for systems having generic condition responsive alarms or indicators.
901 for vehicle mounted alarms or indicators which respond to a condition or stimulus external to the vehicle.

SEE OR SEARCH CLASS:
116, Signals and Indicators, 28 for similar devices which are nonelectrically actuated.

Of burglary or unauthorized use:
This subclass is indented under subclass 425.5. Subject matter in which an alarm or indicator is activated in response to an attempt at unauthorized entry or use of the vehicle.
(1) Note. Classification here requires significant combination of burglar alarm with vehicle.

SEE OR SEARCH THIS CLASS, SUBCLASS:
500 especially 541+ and 568.1+, for burglar alarms, per se.

SEE OR SEARCH CLASS:
180, Motor Vehicles, 287 for antitheft systems which prevent unauthorized use by controlling one or more systems during attempted operation of the vehicle, as by: (1) application of the brakes, (2) stoppage of the fuel supply, or (3) opening of the ignition circuit in response to a timer.
307, Electrical Transmission or Interconnection Systems, 10.2 for antitheft systems which prevent activation of the ignition or starter systems of the vehicle.

Of motorcycles or bicycles:
This subclass is indented under subclass 426. Subject matter wherein the vehicle is a two-wheeled type either motorized or manually propelled.

Responsive to change in voltage or current in a vehicle electrical system:
This subclass is indented under subclass 426. Subject matter including alarms which are actuated by direct sensing of changes in current or voltage within any existing electrical circuit (e.g., domelight or starter) of the vehicle.

Responsive to inertia, vibration, or tilt:
This subclass is indented under subclass 426. Subject matter in which the alarm is sensitive to vibrations or other motions of a vehicle caused by an intruder's actions.

SEE OR SEARCH THIS CLASS, SUBCLASS:
566 for vibration sensitive intrusion alarms, per se.

With entrance/exit time delay:
This subclass is indented under subclass 426. Subject matter wherein actuation of the alarm is delayed for a predetermined time interval to allow a legitimate user of the vehicle to enter or exit the vehicle without sounding the alarm.

For trailer:
This subclass is indented under subclass 425.5. Subject matter wherein the vehicle is a trailer or a motor vehicle combined with a trailer.

SEE OR SEARCH THIS CLASS, SUBCLASS:
687 for condition responsive indicators which respond to the connection or disconnection of circuits of general utility.

SEE OR SEARCH CLASS:
307, Electrical Transmission or Interconnection Systems, subclass 10.8 for trailer lighting circuits with significant recitation of the means for coupling with the circuits of a towing vehicle.

For bicycle:
This subclass is indented under subclass 425.5. Subject matter wherein the vehicle is a bicycle.

SEE OR SEARCH CLASS:
315, Electric Lamp and Discharge Devices: Systems, subclass 78 for generator powered vehicle lighting systems, per se.
362, Illumination, 473 for bicycle signal light systems in combination with illuminating systems.

For school bus:
This subclass is indented under subclass 425.5. Subject matter wherein the vehicle is a school bus.

For taxi:
This subclass is indented under subclass 425.5. Subject matter wherein the vehicle is a taxicab.

SEE OR SEARCH CLASS:
180, Motor Vehicles, subclass 288 for a motor vehicle provided with a safety-promoting means which is responsive to the failure of a taxicab operator to activate the vehicle's
fare meter upon the boarding of a passenger.

Of relative distance from an obstacle:
This subclass is indented under subclass 425.5. Subject matter including indicators which enable a driver to estimate the relative distance to an obstacle such as another vehicle.

Of collision or contact with external object:
This subclass is indented under subclass 425.5. Subject matter including systems which indicate contact between the vehicle and an external object.
(1) Note. Systems classified here must have significant alarm or indication function.

SEE OR SEARCH CLASS:
180, Motor Vehicles, 271 for systems with a control function or other nonalarm response to contact with an external object.

Curb:
This subclass is indented under subclass 436. Subject matter in which the external object is a curb.

Internal alarm or indicator responsive to a condition of the vehicle:
This subclass is indented under subclass 425.5. Subject matter wherein the alarm or indicator is actuated in response to a specific condition of the vehicle and the alarm or indicator communicates with an occupant of the vehicle (e.g., the driver).
(1) Note. Included in this and the indented subclasses are: (a) fully automatic alarms and indicators (e.g., fluid level indicators) and (b) indicators which automatically respond to
a manual actuation of a system (e.g., gear position indicators.

SEE OR SEARCH THIS CLASS, SUBCLASS:
286.01 for automatic or manual alarms and indicators having only nominal vehicle structure.
901 for vehicle mounted alarms or indicators which respond to a condition or stimulus external to the vehicle.

Operation efficiency (e.g., engine performance, driver habits):
This subclass is indented under subclass 438. Subject matter wherein the degree of efficiency in the operation of the vehicle is indicated.
(1) Note. Included here are devices which indicate: (1) relative fuel economy, (2) erratic driving behavior, or (3) other factors related to improper operation of the vehicle.

SEE OR SEARCH THIS CLASS, SUBCLASS:
575 and 576, for devices which determine driver capability or alertness.

Tilt, imbalance, or overload:
This subclass is indented under subclass 438. Subject matter including systems which inform the operator of an unsafe load or weight distribution on the vehicle.

Speed of vehicle, engine, or power train:
This subclass is indented under subclass 438. Subject matter including alarms or indicators which respond to the speed of the vehicle or of a component of its power train.

SEE OR SEARCH THIS CLASS, SUBCLASS:
466 for speed responsive alarms or indicators which communicate with persons outside the vehicle.

SEE OR SEARCH CLASS:
180, Motor Vehicles, 170 for systems in which the speed responsive signal performs a direct control function in one or more of the vehicle's systems.

Tire deflation or inflation:
This subclass is indented under subclass 438. Subject matter wherein the specific condition is a deviation from the proper inflation of a pneumatic tire.
(1) Note. This is the repository for on-board electric alarms or indicators of under inflation in vehicle mounted pneumatic tires and of unbalanced inflation in vehicle mounted paired (dual) tires.
(2) Note. The alarm or indicator here is triggered by the inflation pressure falling below a preset limit. Indicators which directly report a quantitative measurement of the tire pressure are classified in Class 73.

SEE OR SEARCH CLASS:
73, Measuring and Testing, 146 for quantitative measurement of pneumatic tire pressure.
116, Signals and Indicators, 34 for nonelectric tire deflation alarms or indicators.
152, Resilient Tires and Wheels, 415 and 418+ for systems which maintain tire air pressure by means of an on-board air supply.

By indirect detection means (e.g., height measurement):
This subclass is indented under subclass 442. Subject matter wherein the deviation from proper inflation pressure is determined from a measurement of a parameter other than air pressure.

Relative wheel speed:
This subclass is indented under subclass 443. Subject matter wherein the measured parameter is the relative rotational speed of two or more wheels of the vehicle.

With particular telemetric coupling:
This subclass is indented under subclass 442. Subject matter including systems in which a signal, generated by a sensor on the rotating wheel, is transmitted to an alarm or indicator on a nonrotating portion of the vehicle by means other than direct conduction of electricity.

Acoustic wave:
This subclass is indented under subclass 445. Subject matter in which the signal is carried by sound waves generated by a device mounted on the rotating wheel.

SEE OR SEARCH CLASS:
367, Communications, Electrical: Acoustic Wave Systems and Devices, subclass 13, 117, and 137+ for generic acoustic wave transmission systems.

Radio wave:
This subclass is indented under subclass 445. Subject matter in which the signal is carried by electromagnetic waves of radio frequency generated by a transmitter mounted on the rotating wheel.

Inductive:
This subclass is indented under subclass 445. Subject matter wherein a coil or permanent magnet is mounted on the wheel in spaced relationship with a coil mounted on a nonrotating portion of the vehicle.

Temperature:
This subclass is indented under subclass 438. Subject matter wherein the specific condition is the temperature of a particular component of the vehicle.

Fluid level:
This subclass is indented under subclass 438. Subject matter wherein the specific condition is the depth of a fluid in a reservoir.

Of hydraulic brake fluid:
This subclass is indented under subclass 450. Subject matter wherein the fluid is hydraulic brake fluid.

Of fuel:
This subclass is indented under subclass 450. Subject matter wherein the fluid is a fuel.

Of lubricant (e.g., engine oil):
This subclass is indented under subclass 450. Subject matter wherein the fluid is a lubricant.

Fluid pressure:
This subclass is indented under subclass 438. Subject matter wherein the specific condition is the pressure in a contained fluid.

Of brake fluid:
This subclass is indented under subclass 451. Subject matter wherein the fluid is hydraulic brake fluid.

Brake or clutch condition:
This subclass is indented under subclass 438. Subject matter wherein the specific condition is a physical property of the vehicle brake, or clutch, system.

Wear:
This subclass is indented under subclass 453. Subject matter wherein the physical property of the brake or clutch system is the degree of wear of the linings or pads.

SEE OR SEARCH CLASS:
192, Clutches and Power-Stop Control, subclass 30 for nonelectric clutch wear indicators.

Battery charging system condition:
This subclass is indented under subclass 438. Subject matter wherein the specific condition is the degree of charge in a battery or the current drawn from, or supplied to, a battery.

Gear position:
This subclass is indented under subclass 438. Subject matter wherein the indicator informs the driver as to which one of several selectable gear combinations available in a manual or automatic transmission is engaged.

SEE OR SEARCH CLASS:
116, Signals and Indicators, subclass 28.1 for mechanical gear position indicators.

Reminder:
This subclass is indented under subclass 438. Subject matter wherein the alarm or indicator informs the operator that a vehicle system requires an action on his part.

Of seat belt application:
This subclass is indented under subclass 457. Subject matter wherein the required action is the application of a seat belt.

SEE OR SEARCH CLASS:
180, Motor Vehicles, 268 for systems in which the seat belt mechanism deactivates the ignition circuit or performs some other control function.

Of headlight energization:
This subclass is indented under subclass 457. Subject matter wherein the required action is the activation or deactivation of a headlight circuit.

SEE OR SEARCH CLASS:
315, Electric Lamp and Discharge Devices: Systems, subclass 83 for indicators of high or low beam headlamp circuit activation.

Of parking brake application:
This subclass is indented under subclass 457. Subject matter wherein the required action is the application, or release, of a parking brake.

Of service interval expiration:
This subclass is indented under subclass 457. Subject matter
wherein the required action is the performance of a periodic maintenance function.

Lamp or lamp circuit condition:
This subclass is indented under subclass 438. Subject matter in which fault conditions within a vehicle illumination or signal light system are indicated.

SEE OR SEARCH CLASS:
315, Electric Lamp and Discharge Devices: Systems, 82 for vehicle headlamp systems which may include fault indicators.
362, Illumination, 459 for vehicle mounted illumination devices which may include fault, or position (e.g., aiming) indicators.

Plural conditions:
This subclass is indented under subclass 438. Subject matter including systems or devices which combine two or more automatic alarms or indicators, or in which a single alarm or indicator serves two or more diverse functions.

SEE OR SEARCH THIS CLASS, SUBCLASS:
439 for alarms or indicators which respond to a combination of two or more related conditions which measure engine efficiency.

With voice warning:
This subclass is indented under subclass 459. Subject matter in which the alarm or indicator includes a recorded or synthesized voice signal.

With particular display means:
This subclass is indented under subclass 459. Subject matter wherein plural diverse indicators share a common housing or
mounting.

Digital:
This subclass is indented under subclass 461. Subject matter wherein one or more of the indicators is a digital display.

External alarm or indicator of movement:
This subclass is indented under subclass 425.5. Subject matter including external signalling systems which automatically respond to a state of motion (e.g., turning, acceleration, deceleration, backing) of the vehicle and which communicate with persons outside the vehicle (e.g., other drivers, pedestrians).
(1) Note. The state of motion may be sensed directly, as by an accelerometer, or it may be sensed by devices responsive to the activation of a system which causes the movement (e.g., the steering linkage or the transmission gear selector).

Plural indications (e.g., go, slow, stop):
This subclass is indented under subclass 463. Subject matter in which two or more diverse motion indicators are combined.

Turning or steering:
This subclass is indented under subclass 463. Subject matter in which the external signal indicates that the vehicle is executing a turning movement.

SEE OR SEARCH THIS CLASS, SUBCLASS:
475 for systems which are manually set to indicate the operator's intention to initiate a turning movement and may be automatically cancelled upon completion of the turn.

Speed:
This subclass is indented under subclass 463. Subject matter in which the external signal indicates the speed of the vehicle or warns of a condition of overspeed or underspeed.

SEE OR SEARCH THIS CLASS, SUBCLASS:
441 for speed responsive alarms or indicators which communicate with occupants of the signalling vehicle.

Acceleration or deceleration:
This subclass is indented under subclass 463. Subject matter in which the external signal indicates a change in the speed of the vehicle.
(1) Note. External signal lights which are actuated by: (a) an inertial sensor, (b) a switch associated with the accelerator pedal, or (c) a device which senses changes in engine vacuum are classified here. Brake lights, which are actuated by a switch associated with the brake pedal, are provided for elsewhere in this class (340).

SEE OR SEARCH THIS CLASS, SUBCLASS:
479 for brake lights, which are actuated by a switch associated with the brake pedal.

SEE OR SEARCH CLASS:
180, Motor Vehicles, 282 for systems or devices which directly control a vehicle subsystem (e.g., an ignition circuit) in response to an acceleration or deceleration.

External signal light system:
This subclass is indented under subclass 425.5. Subject matter wherein the alarm or indicator is a manually actuated signal light system which communicates with persons outside the vehicle (e.g., other drivers, pedestrians).
(1) Note. Systems must be manually actuated but may be automatically deactuated.

SEE OR SEARCH CLASS:
315, Electric Lamp and Discharge Devices: Systems, appropriate subclasses for signal light systems of general utility.

With two or more intensity levels (e.g., day or night):
This subclass is indented under subclass 468. Subject matter wherein the signal light system can operate at two or more brightness levels.
(1) Note. The selection of brightness level may be made either manually or automatically.

Pass - no pass:
This subclass is indented under subclass 468. Subject matter in which the signal is used to indicate to the driver of an overtaking vehicle whether or not it is safe to pass the signalling vehicle.

Hazard warning or distress signalling:
This subclass is indented under subclass 468. Subject matter including systems designed to indicate to other drives that the signalling vehicle is inoperative, or is being operated in an unusual manner and itself constitutes a hazard to other vehicles.

Auxiliary signal permanently attached to vehicle:
This subclass is indented under subclass 471. Subject matter including alarms or indicators which are attached to a vehicle (e.g., police car light bar), but which are not "standard" vehicle signalling systems.

Portable signal:
This subclass is indented under subclass 471. Subject matter including alarms or indicators which may be carried in a vehicle, and displayed on or off the vehicle, and which are not normally attached to the vehicle.

SEE OR SEARCH THIS CLASS, SUBCLASS:
908 for similar portable hazard warning signals placed on a highway to warn of hazards, per se.

SEE OR SEARCH CLASS:
116, Signals and Indicators, 63 for similar signals without electrical components.

With audible signal:
This subclass is indented under subclass 468. Subject matter wherein the signal light system is combined with an audible signal.

SEE OR SEARCH THIS CLASS, SUBCLASS:
326 for systems of general utility combined with audible signals.

Turn signal:
This subclass is indented under subclass 468. Subject matter wherein an external signal is manually actuated to indicate the driver's intention to execute a turning movement.

SEE OR SEARCH THIS CLASS, SUBCLASS:
465 for external signals which automatically indicate a turning motion in response to actuation of the vehicle steering system.

With automatic cancelling:
This subclass is indented under subclass 475. Subject matter wherein the external signal is automatically deactivated after the turn is completed.

By predetermined time interval or distance:
This subclass is indented under subclass 476. Subject matter wherein deactivation of the signal occurs after a specified time interval has elapsed or after a specified distance has been travelled.

SEE OR SEARCH THIS CLASS, SUBCLASS:
815.3 for visual signals of general utility which automatically cancel after a predetermined elapsed time interval.

With plural bulbs sequentially flashed:
This subclass is indented under subclass 475. Subject matter wherein the external signal consists of a timed sequence of multiple flashing lights.

Brake light:
This subclass is indented under subclass 468. Subject matter wherein the signal light is actuated by a switch associated with the brake system of the vehicle.

SEE OR SEARCH THIS CLASS, SUBCLASS:
453 for systems which automatically respond to a physical condition of the brake system other than its activation.

Electromagnetically actuated mechanical signal:
This subclass is indented under subclass 425.5. Subject matter in which the indicator is a mechanical device which is caused to move from an inactive position to a display position by means of a solenoid or motor.

SEE OR SEARCH CLASS:
116, Signals and Indicators, 28 for similar devices which are actuated manually or pneumatically.

Wigwag type:
This subclass is indented under subclass 480. Subject matter including devices which oscillate during display.

Normally encased:
This subclass is indented under subclass 480. Subject matter including devices which are contained in a protective housing at least while in the inactive (undisplayed) position.

Plural concurrent indicators:
This subclass is indented under subclass 482. Subject matter including two or more individually actuated signal members which are capable of simultaneous display.

SEE OR SEARCH THIS CLASS, SUBCLASS:
488 for similar devices which are not normally encased nor simultaneously displayable.

Sliding sign or shutter:
This subclass is indented under subclass 482. Subject matter wherein the device is a plane sheet which is brought into display position by a rectilinear motion.

Window exhibited sign or shutter:
This subclass is indented under subclass 482. Subject matter wherein the indicator remains in the protective housing both during display and during inactive storage and is displayed through a transparent window when activated.
(1) Note. The electromagnetic actuation may be applied to: (1) the indicator member, (2) the window, or (3) a shutter
which covers the window.

SEE OR SEARCH CLASS:
116, Signals and Indicators, 42 for similar devices which are manually or pneumatically actuated.

Drum:
This subclass is indented under subclass 485. Subject matter wherein the indicator is a cylinder or drum.

Pivoting:
This subclass is indented under subclass 480. Subject matter wherein the indicator is brought into display position by rotation about an axis.

SEE OR SEARCH CLASS:
116, Signals and Indicators, 51 for pivoted signals or indicators which are manually or pneumatically actuated.

Multiple indicators:
This subclass is indented under subclass 487. Subject matter wherein more than one indicator may be brought into display position by rotation about an axis.

Three or more positions:
This subclass is indented under subclass 487. Subject matter wherein a single indicator may be displayed in more than two positions.

Vertical axis:
This subclass is indented under subclass 489. Subject matter wherein the axis of rotation of the indicator is perpendicular to the earth's surface.

CONDITION RESPONSIVE INDICATING SYSTEM:
This subclass is indented under the class definition. Subject matter where an electrical means provides a humanly perceptible signal in response to the attainment of a predetermined condition.
(1) Note. This subclass includes, for example, alarm circuits or signals which are automatically responsive to some condition, such as excessive temperature. Alarm devices which are manually activated are classified in Class 340, subclasses 286.04+.
(2) Note. Condition responsive indicators in combination with structural details of a particular art device are classified with the art device; e.g., telemetering systems, data processing systems, chemical apparatus, tools, or vehicles.
(3) Note. The combination of a condition responsive indicator and a switching system is classified herein; however, if the indicator means is merely an ancillary element, classification is elsewhere; e.g. Class 307 or 361.
(4) Note. Particular quantitative testing or measuring means in combination with an electrical condition responsive indicator are classified with the appropriate testing and measuring class, except if the quantitative measurement is peculiar to an alarm device; e.g., a smoke detector alarm system with a meter indication of its power supply.
(5) Note. If a qualitative testing, measuring, or monitoring means is claimed to be permanently associated with the environment being tested, such as a machine monitoring device, classification is in Class 340, while if it is temporarily associated, as in a portable test set, classification is in the appropriate testing and measuring class.
(6) Note. The class definition of this class, under "SEARCH CLASS", refers to the many other classes which contain alarms and indicators.

SEE OR SEARCH THIS CLASS, SUBCLASS:
438 and 463+, for vehicle condition responsive alarms or indicators.
825.32 for an authorization control system having an alarm
or indication of improper access.
825.36 for a selective communication system with an indication or alarm.
870.09 for telemetering systems which have added alarms.
910 and 917+, for traffic control indicators which are responsive to vehicle detectors.

SEE OR SEARCH CLASS:
116, Signals and Indicators, appropriate subclasses, especially subclass 67 and 200+ for nonelectrical alarms and indicators which are automatically responsive to a condition.
200, Electricity: Circuit Makers and Breakers, appropriate subclasses under subclass 52 for circuit makers and breakers whose controllers are responsive to a condition.
234, Selective Cutting (e.g., Punching), 22 for a selective cutting device having means responsive to a given operating condition (or malfunction) to impose an auxiliary control thereon.
307, Electrical Transmission or Interconnection Systems, 86, 97, 99, 116+, and 152 for electrical transmission or switching systems which are responsive to a condition.
315, Electric Lamp and Discharge Devices: Systems, subclass 129 for electric lamp or discharge systems with a signal, indicator, or alarm.
327, Miscellaneous Active Electrical Nonlinear Devices, Circuits, and Systems, subclass 187 for a stable state circuit which is externally effected and subclasses 509+ for miscellaneous circuits which are externally effected.
331, Oscillators, 65 for electric oscillation generators combined with means responsive to an external physical condition.
336, Inductor Devices, subclass 30 for inductors with condition responsive adjusting means.
338, Electrical Resistors, 13 for resistors whose resistance value is responsive to a condition.
361, Electricity: Electrical Systems and Devices, 1 for safety and protection systems which may be condition responsive; subclasses 139+ for electrical relay systems; and subclasses 271+ for capacitors which are automatically responsive or nonresponsive to a condition.
367, Communications, Electrical: Acoustic Wave Systems and Devices, 93 and 136 for acoustic wave-type intruder
detectors.

With particular system function (e.g., temperature compensation, calibration):
This subclass is indented under subclass 500. Subject matter with significant functional relationship between the condition sensing means and indicating means, additional to the basic condition responsive actuating function.
(1) Note. Typical additional functions are special processes, priority of urgency, adjustment, temperature compensation, and calibration.

SEE OR SEARCH CLASS:
73, Measuring and Testing, 1.01 for calibration of a measuring device.
374, Thermal Measuring and Testing, 1 for calibration of a thermally responsive device.

Acknowledgement:
This subclass is indented under subclass 501. Subject matter together with means to effect a change in the indication to further indicate that the condition has been noted.
(1) Note. Acknowledgement exists when a remote office sends an alert signal in response to the sensed condition to a central office where the signal is indicated; and the central office then responds with an acknowledgement signal (which may or may not return to the remote office), which causes a change in the indication at the central office. This should be distinguished from interrogation which occurs when the controller at the central office sends an interrogating signal such as pulse or code to the remote office, and the remote office returns a signal indicative of the original signal and any intervening disturbances. This should also be distinguished from "answer-back" which occurs when the remote office sends an alarm signal to the central office, and the central office returns a signal indicative of the successful completion of the alarm function.

With ringback:
This subclass is indented under subclass 502. Subject matter where an additional indication is provided after acknowledgement, indicating that the sensed condition is further changes (e.g., corrected, removed, or worsened).
(1) Note. The additional indication may be caused by an additional signal, or a return of the original signal to normal. However, for classification here, more than a mere inherent return of the indication to normal is necessary. Usually means is provided to reset the system to normal indication.

Answer-back:
This subclass is indented under subclass 501. Subject matter where a signal indicative of receipt of the indication is returned to the location originating the alarm.
(1) Note. See subclass 502 Note for distinction between answer-back and acknowledgement systems.

Interrogator-responder:
This subclass is indented under subclass 501. Subject matter where the indication is only given upon receipt of an initiating signal.
(1) Note. The response signal may be indicative of the original interrogating signal and any intervening disturbances. However, the condition is indicated only in response to the interrogation. See subclass 502 for acknowledgement systems, and the Note thereunder for the distinction between interrogation and acknowledgement systems.

Alarm system supervision:
This subclass is indented under subclass 501. Subject matter where there is continuous monitoring of the operativeness of the alarm circuits in the system.
(1) Note. The system having its operativeness monitored is referred to as the "primary system" in the definitions of of the subclasses indented hereunder.
(2) Note. Supervision should be distinguished from automatic testing of the system as in subclass 516 below, in that, supervision implies continuous surveillance of the system while automatic testing is periodic.

SEE OR SEARCH THIS CLASS, SUBCLASS:
635 for monitoring of a system in which the combination to form a condition responsive primary alarm system is not recited.

Fail-safe:
This subclass is indented under subclass 506. Subject matter having the primary alarm circuit itself organized so as to give alarm upon its failure.

Redundant (e.g., added circuit or loop):
This subclass is indented under subclass 506. Subject matter having either duplicate primary alarm circuits, an added circuit, or double loops in the primary alarm circuit, to monitor at least an element of the primary circuit.

Plural or diverse current sources:
This subclass is indented under subclass 506. Subject matter having plural, or diverse current sources, with the supervisory current typically being imposed on the primary alarm circuit.
(1) Note. Systems using polarity reversal are not classified herein, but are usually classified in subclass 513.

Bridge or potential divider:
This subclass is indented under subclass 506. Subject matter having the primary alarm circuit arranged with at least one potential divider from which supervisory currents are derived.

Threshold or window (e.g., of analog electrical level):
This subclass is indented under subclass 506. Subject matter wherein the supervisory circuit is coupled to the primary alarm circuit and is responsive to the signal therein attaining a predetermined level or range of levels.

Pulse:
This subclass is indented under subclass 506. Subject matter having electrical pulses, either from an energizing pulse source, or from some circuit means forming pulses related to an electrical alarm signal, in either the primary or supervisory circuit.

Diode:
This subclass is indented under subclass 506. Subject matter having a diode added to the primary alarm circuit by which a supervisory current may be effective.

Testing:
This subclass is indented under subclass 501. Subject matter where the operativeness of the system is determined at discrete times.

SEE OR SEARCH THIS CLASS, SUBCLASS:
501 for alarm system calibration.

Simulation of condition:
This subclass is indented under subclass 514. Subject matter where the test is performed by imitation of a condition.
(1) Note. The test is normally performed at the sensor to imitate the condition being monitored.

Automatic (e.g., periodic, start-up):
This subclass is indented under subclass 514. Subject matter where the test is invariably performed at periodic intervals, or as a function of the energization or deenergization of the primary alarm system.

Selection from a plurality of sensed conditions:
This subclass is indented under subclass 501. Subject matter including more than one sensing means and having a particular relationship therebetween.
(1) Note. Mere duplication of sensing means is insufficient for classification herein.

SEE OR SEARCH THIS CLASS, SUBCLASS:
825 for selective communication systems.

SEE OR SEARCH CLASS:
307, Electrical Transmission or Interconnection Systems, 116 for condition responsive electrical switching systems.

Scanning:
This subclass is indented under subclass 517. Subject matter where the sensor means are monitored one at a time in a predetermined order.

Worst condition:
This subclass is indented under subclass 517. Subject matter where the system responds to the sensor means reporting the condition that deviates the most from a predetermined setting.
(1) Note. Examples of the worst conditions are the greatest unbalance, the greatest difference from a standard, or the most extreme variation in a given direction.

First sensed exclusively indicated:
This subclass is indented under subclass 517. Subject matter where the first condition to become abnormal is selected for indication.
(1) Note. Subsequent alarm indications may be locked out, or may be displayed to show order of sensing.

Plural diverse conditions:
This subclass is indented under subclass 517. Subject matter responsive to at least two disparate conditions (e.g., intrusion and flame).

Combined for response:
This subclass is indented under subclass 521. Subject matter where the system responds to a specified combination of the sensed conditions.

Particular sequence of conditions:
This subclass is indented under subclass 517. Subject matter responsive to a given series of events.

Condition position indicator:
This subclass is indented under subclass 517. Subject matter wherein the indication imparts information as to the location, in addition to the attainment, of the condition being monitored.

Display board:
This subclass is indented under subclass 524. Subject matter wherein the means providing indication include a plurality of visual indicators, each of which is actuated by one of the sensors, located upon a surface at a single location.
(1) Note. The display may mimic the sensor array.

SEE OR SEARCH THIS CLASS, SUBCLASS:
286.13 for a manually operated alarm with a mapping or mimicking indicator.

Predetermined rate of occurrence:
This subclass is indented under subclass 501. Subject matter in which a specified number of events (one or more) must occur within a specified time period in order to cause or prevent the actuation of the humanly perceptible signal.

SEE OR SEARCH THIS CLASS, SUBCLASS:
609 for a fluent particle counting flow rate alarm system.

Time delay:
This subclass is indented under subclass 501. Subject matter having a circuit which delays the transmission of a signal, or the output of a transducer, for a desired length of time.
(1) Note. Time delay introduced by means other than circuitry, e.g., a transducer structure providing such a delay, is not classified herein.

SEE OR SEARCH CLASS:
70, Locks, 267 for time interval controlled lock operating mechanisms.
327, Miscellaneous Active Electrical Nonlinear Devices, Circuits, and Systems, 261 for miscellaneous time delay circuits.
361, Electricity: Electrical Systems and Devices, subclass
91.3 for overvoltage protection with time delay and subclass 195 for time-delay systems.
368, Horology: Time Measuring Systems or Devices, 10 for clocks combined with alarm or signal.

Entrance/exit:
This subclass is indented under subclass 527. Subject matter where the time delay allows an authorized person to either disarm the alarm or exit a protected area before the humanly perceptible signal is actuated.

Condition persistence:
This subclass is indented under subclass 527. Subject matter where there is a lapse of time between the sensing of the condition and the giving of the indication, where the indication is given only if the condition persists for the duration of the time lapse.

Capacitor:
This subclass is indented under subclass 529. Subject matter where the time-delay circuit is controlled by the charging or discharging of a capacitor.

With particular coupling link:
This subclass is indented under subclass 500. Subject matter having specific connecting means between the sensing and indicating means.

SEE OR SEARCH THIS CLASS, SUBCLASS:
870.28 for continuously variable indication via a radiant energy beam.

Having particular safety function:
This subclass is indented under subclass 531. Subject matter wherein the particular communication link has a specific limitation to enable safe operation in a particular environment (e.g., in the presence of explosive vapor).
(1) Note. "Intrinsic safety" systems are classified herein.

SEE OR SEARCH CLASS:
361, Electricity: Electrical Systems and Devices, 1 for electrical safety systems, generally.

Wired:
This subclass is indented under subclass 531. Subject matter with a transmitting means connected to indicating means by an arrangement of conductors.
(1) Note. To complete the search for this subject matter, the search should extend into the appropriate fields of classification of wired coupling means, such as Class 178, for Telegraphy; Class 379 for Telephonic Communications.

Coded message:
This subclass is indented under subclass 533. Subject matter with a pulse code source in the transmitting means.
(1) Note. The message may relate to location or to the condition sensed.

SEE OR SEARCH CLASS:
341, Coded Data Generation or Conversion, 20 and 173+ for pulse code transmitter.

Mechanical code means (e.g., coded disc):
This subclass is indented under subclass 534. Subject matter having a switching device actuated by a mechanical actuator (e.g., cam or disc) upon an occurrence of the alarm condition.

SEE OR SEARCH THIS CLASS, SUBCLASS:
287 for manually actuated signal box-type fire alarm boxes.

SEE OR SEARCH CLASS:
178, Telegraphy, subclass 2 and 79 for code transmitters in telegraph systems.

Noninterfering:
This subclass is indented under subclass 533. Subject matter provided with means for preventing the transmission of other signals while a first signal is being transmitted.

SEE OR SEARCH THIS CLASS, SUBCLASS:
295 for this subject matter when not automatically responsive to a condition.

SEE OR SEARCH CLASS:
178, Telegraphy, 17 for telegraphy systems having noninterfering transmitters.

With impedance level coding:
This subclass is indented under subclass 533. Subject matter where the sensor or transmitter output is encoded by selection of specifically related impedance.
(1) Note. Graded or binary coded decimal coding for analog signals are found in Class 340, subclass 870.27 for telemetering systems.

Combined with power line:
This subclass is indented under subclass 533. Subject matter where the wired communication link is a wired electrical power transmission system.
(1) Note. The system need not be the power source of the indicating system.

SEE OR SEARCH THIS CLASS, SUBCLASS:
310.01 for transmitting a manually initiated alarm signal over a power line.

Radio:
This subclass is indented under subclass 531. Subject matter where the communication link is by radio waves (i.e., other than light, X, or gamma rays, etc.).

SEE OR SEARCH CLASS:
343, Communications: Radio Wave Antennas, appropriate subclasses for radio wave communication systems in general.
375, Pulse or Digital Communications, subclasses 200-294 for the radio link, per se.

Specific condition:
This subclass is indented under subclass 500. Subject matter distinguished by the particular detected condition in response to which the signal is produced.
(1) Note. This subclass includes, for example, alarms which are automatically operated in response to some condition, such as excessive temperature.

SEE OR SEARCH CLASS:
42, Firearms, subclass 1.01 for firearms with miscellaneous indicators.
91, Motors: Expansible Chamber Type, subclass 1 with signal or indicator.
92, Expansible Chamber Devices, subclass 5 with signal or indicator.
116, Signals and Indicators, appropriate subclasses, especially 67 and 200+ for nonelectrical alarms and indicators which are automatically responsive to a condition.
200, Electricity: Circuit Makers and Breakers, appropriate subclasses under subclass 52 for circuit makers and breakers whose controllers are responsive to a condition.
234, Selective Cutting (e.g., Punching, 22 for a selective cutting device having means responsive to a given operating condition (or malfunction) to impose an auxiliary control thereon.
307, Electrical Transmission or Interconnection Systems, 86, 97, 99, 116+, and 152 for electrical transmission and switching systems which are responsive to a condition.
315, Electric Lamp and Discharge Devices: Systems, 129 for electric lamp or discharge systems with a signal, indicator, or alarm.
331, Oscillators, 65 for electric oscillation generators combined with means responsive to an external physical Condition.
336, Inductor Devices, subclass 30 for inductors with condition responsive adjusting means.
338, Electrical Resistors, 13 for resistors whose resistance value is responsive to a condition.
361, Electricity: Electrical Systems and Devices, 1 for safety and protection systems which may be condition responsive; subclasses 170+ for electrical relay systems; and subclass 280 for capacitors which are automatically responsive or nonresponsive to a condition.

Intrusion detection:
This subclass is indented under subclass 540. Subject matter where the entry or attempted entry by a living being (intruder) into a protected area is detected.

SEE OR SEARCH CLASS:
43, Fishing, Trapping, and Vermin Destroying, subclass 59 for burglar traps.
109, Safes, Bank Protection, or a Related Device, subclass 21, 31, and 38 for alarms, signals, or indicators.
116, Signals and Indicators, 75 for mechanical burglar alarms.
182, Fire Escape, Ladder, or Scaffold, subclass 18 with indicator, signal, or alarm.
200, Electricity: Circuit Makers and Breakers, subclass 61.93 for anti-intrusion type switch.

Lock:
This subclass is indented under subclass 541. Subject matter wherein unauthorized or improper operation of a latching device operated by a key, dial, etc., is detected.

SEE OR SEARCH CLASS:
70, Locks, 432 for locks with condition indicators; subclasses 262+ for systems, and subclasses 266+ for operating mechanism.
92, Expansible Chamber Devices, subclass 5 for locks with a signal or indicator.
200, Electricity: Circuit Markers and Breakers, 61.64 for lock, bolt, or keeper actuated switches.

Permutation:
This subclass is indented under subclass 542. Subject matter where the lock is combination lock (dial, push-button, etc.).

SEE OR SEARCH CLASS:
70, Locks, 286 for combination locks, per se, and subclasses 432+ for locks with condition indicators.
361, Electricity: Electrical Systems and devices, 171 for code responsive relay systems.

Disturbance of fluid pressure:
This subclass is indented under subclass 541. Subject matter wherein the intrusion is detected by a pressure sensing device responsive to confined fluid under superatmosphere, subatmosphere, or time-varying pressure.
(1) Note. The confined fluid may be within a barrier bounding the protected area or within the entire area.

SEE OR SEARCH THIS CLASS, SUBCLASS:
626 for pressure responsive indication of more general utility.

Door or window movement:
This subclass is indented under subclass 541. Subject matter responsive to the movement of a temporary closure for intrusion detection.
(1) Note. For example, a wall or building is a permanent barrier, but a door thereof is only a temporary barrier.

SEE OR SEARCH CLASS:
49, Movable or Removable Closures, 13 for a closure condition signal or indicator.
116, Signals and Indicators, 86 for a mechanical burglar alarm on a door or window.
160, Flexible or Portable Closure, Partition, or Panel, subclass 10 with signal or indicator.
200, Electricity: Circuit Makers and Breakers, 61.62 for closure, closure operator, or accessory switches; and subclass 61.93 for intrusion-responsive switches.
232, Deposit and Collection Receptacles, subclasses 35-37 for door-operated signals and indicators.

Specified sensor:
This subclass is indented under subclass 545.1. Subject matter having specific detail of a device which is designated to produce an indicative signal in response to an event or stimulus within its detection zone.

SEE OR SEARCH CLASS:
200, Electricity: Circuit Makers and Breakers, subclass 61.93 for such switches, per se.

Sensing of electromagnetic energy (e.g., light, infrared, or microwave):
This subclass is indented under subclass 545.2. Subject matter in which the movement is sensed according to a
detected level of radiant energy.
(1) Note. Conditions sufficient for classification herein include:
(a) a specified type of electromagnetic energy which becomes present or absent at a sensor, or
(b) a threshold change in a preexisting electromagnetic energy field which occurs at a sensor.

SEE OR SEARCH THIS CLASS, SUBCLASS:
552 for intrusion detection by sensing the disturbance of electromagnetic waves in general.

SEE OR SEARCH CLASS:
250, Radiant Energy, appropriate subclasses for general radiant energy responsive electric signaling without intrusion detection purpose.

Sensing of electrical parameter (e.g., piezoelectricity or capacitance):
This subclass is indented under subclass 545.2. Subject matter in which the movement is sensed according to a detected level of particular electrical power energy.
(1) Note. A piezoelectric or a capacitive sensing element is appropriate for this subclass; the mere making or breaking of an electrical circuit is insufficient for classification herein.

SEE OR SEARCH THIS CLASS, SUBCLASS:
561 for intrusion detection by sensing the disturbance of an electric field in general.

SEE OR SEARCH CLASS:
324, Electricity: Measuring and Testing, appropriate subclasses for circuit testing by sensing electrical parameter.

Inertia-type sensor (e.g., mercury or pendulum switch):
This subclass is indented under subclass 545.2. Subject matter in which the movement is detected by a switch which is
capable of sensing acceleration, shock, vibration, and abrupt change in velocity.

SEE OR SEARCH CLASS:
73, Measuring and Testing, 488 for mechanically measuring and testing of speed, velocity, or acceleration, and 570+ for mechanically measuring and testing of vibration.

Door, cover, or lid for self-contained article (e.g., refrigerator, mailbox, drawer, cabinet, or box):
This subclass is indented under subclass 545.1. Subject matter wherein the door or window is part of a structure other than a building or room.

SEE OR SEARCH THIS CLASS, SUBCLASS:
569 for an indicator responsive to an article placement or removal from a mail box.
570 for an indicator responsive to an article placement or removal from a drawer.

SEE OR SEARCH CLASS:
232, Deposit and Collection Receptacles, subclasses 35-37 for letter box door-operated signals and indicators without intrusion detection purpose.

Specified door or window portion (e.g., doorknob):
This subclass is indented under subclass 545.1. Subject matter responsive to the movement of a particular element of the door or window, other than the door or window panel itself.

Specified door or window attachment (e.g., shade or blind):
This subclass is indented under subclass 545.1. Subject matter wherein an opening which is covered by a door or window is additionally covered by a further element whose movement is sensed.

SEE OR SEARCH CLASS:
160, Flexible or Portable Closure, Partition, or Panel, subclass 10 for a signal or indicator without intrusion detection purposes.

Plural doors or windows:
This subclass is indented under subclass 545.1. Subject matter responsive to the movement of any door or window of a plurality of doors or windows.

Portable:
This subclass is indented under subclass 545.2. Subject matter where the alarm means is not permanently attached to the door or window, is self-contained in a single housing, and is of such size and weight to be transportable by a person.

Magnetic sensor:
This subclass is indented under subclass 545.2. Subject matter in which movement is detected by a device containing or responsive to, a magnet or electromagnet.

Plug or cord tension sensor:
This subclass is indented under subclass 545.2. Subject matter in which the movement is sensed by the tension in a cord or wire or plug and socket.

SEE OR SEARCH CLASS:
200, Electricity: Circuit Makers and Breakers, subclass 61.93 for anti-intrusion switches.

Rotatable sensor:
This subclass is indented under subclass 545.2. Subject matter in which the movement is sensed by a pivotally mounted feeler-type sensor.

SEE OR SEARCH CLASS:
200, Electricity: Circuit Makers and Breakers, subclass 61.93 for such switches, per se.

Partition penetration:
This subclass is indented under subclass 541. Subject matter responsive to the condition of a barrier member of a structure.
(1) Note. Barrier members of a structure may be permanent, e.g., building walls, or temporary, e.g., doors.

SEE OR SEARCH THIS CLASS, SUBCLASS:
545.1 for subject matter responsive to movement of a door or window.
652 for "break-wired" systems, per se.

SEE OR SEARCH CLASS:
52, Static Structures (e.g., Buildings), 783.1 for window panes, per se; and subclass 105 for static structures with indicia.
200, Electricity: Circuit Makers and Breakers, subclass 61.08 for frangible switches.

Disturbance of magnetic field:
This subclass is indented under subclass 541. Subject matter responsive to the change of a magnetic field caused by the presence or motion of an intruder.

SEE OR SEARCH CLASS:
324, Electricity: Measuring and Testing, 200 for magnetic field testing or measurement.

Disturbance of electromagnetic waves:
This subclass is indented under subclass 541. Subject matter responsive to the intruder disturbing electromagnetic waves.

SEE OR SEARCH CLASS:
342, Communications: Directive Radio Wave Systems and Devices (e.g., Radar Radio Navigation), 27 for reflective wave presence detection.

Standing waves:
This subclass is indented under subclass 552. Subject matter wherein the electromagnetic waves are stationary (i.e., have maxima and minima at fixed positions).

Doppler effect:
This subclass is indented under subclass 552. Subject matter responsive to the frequency change of a reflected electromagnetic wave caused by motion of a reflecting object.

Light:
This subclass is indented under subclass 552. Subject matter wherein the electromagnetic waves are in the visible range (4,000-7,000A).

SEE OR SEARCH CLASS:
250, Radiant Energy, 221 for photocell systems responsive to animate or inanimate objects.

Beam:
This subclass is indented under subclass 555. Subject matter wherein the light is gathered and directed into substantially parallel rays.
(1) Note. The light is generally gathered into one or more groupings, each having a relatively small cross-sectional area with respect to the dimensions of the protected area.

Laser:
This subclass is indented under subclass 556. Subject matter wherein the light beam source is of the coherent, stimulated emission type.

Disturbance of electric field:
This subclass is indented under subclass 541. Subject matter responsive to the disturbance of an electric field (e.g., capacitance).

SEE OR SEARCH CLASS:
307, Electrical Transmission or Interconnection Systems, 116 for a proximity responsive switching system.
361, Electricity: Electrical Systems and Devices, 179 for proximity responsive relay systems.

Capacitance:
This subclass is indented under subclass 561. Subject matter wherein the electric field disturbance is detected by a change of capacitance in the sensing system.

With bridge:
This subclass is indented under subclass 562. Subject matter wherein the capacitance change sensing system is a bridge circuit.

Fence:
This subclass is indented under subclass 562. Subject matter where the capacitance sensor surrounds the protected area.

Responsive to intruder energy:
This subclass is indented under subclass 541. Subject matter responsive to the energy generated by the intrusion, or of the intruder's body.
(1) Note. The systems herein are generally passive. The term "generated" should be distinguished from the term "disturbance" used in subclasses 551-561 which implies a pre-existing energy field which is modified by the intrusion.

Vibration:
This subclass is indented under subclass 565. Subject matter responsive to mechanical disturbance.

SEE OR SEARCH CLASS:
367, Communications, Electrical: Acoustic Wave Systems and Devices, subclass 136 for intruder responsive acoustic wave systems.

Electromagnetic energy:
This subclass is indented under subclass 565. Subject matter responsive to electromagnetic energy.

SEE OR SEARCH THIS CLASS, SUBCLASS:
552 for disturbance of electromagnetic waves.

Article placement or removal (e.g., anti-theft):
This subclass is indented under subclass 540. Subject matter responsive to a state of an object being put in or taken away
from a protected area.

SEE OR SEARCH THIS CLASS, SUBCLASS:
541 for intrusion detection.
573.1 for human or animal condition.

SEE OR SEARCH CLASS:
53, Package Making, subclass 507 for alarms, signals, or indicators.
169, Fire Extinguishers, subclass 23 for alarms with extinguishing systems.
232, Deposit and Collection Receptacles, subclasses 34-37 for a mailbox having signals and indicators.

Signal-carrying conduit between sensor and article (e.g., cable, power cord, or data link):
This subclass is indented under subclass 568.1. Subject matter wherein the placement or removal is determined by monitoring the integrity of a conductor which is physically attached to, or part of, the article and is in signal communication with a sensor.

SEE OR SEARCH THIS CLASS, SUBCLASS:
531 for a specific connecting means between the sensing and indicating means.

Power cord:
This subclass is indented under subclass 568.2. Subject matter wherein the placement or removal is determined by monitoring the integrity of an electric supply conductor which is physically attached to, or part of, the article and is in signal communication with a sensor.
(1) Note. Art in this subclass is directed to detecting the removal of an electronic device (e.g., computer or television) by the removal of its power cord from a wall outlet.

SEE OR SEARCH THIS CLASS, SUBCLASS:
538 for condition responsive alarm sending through the power
line, and wherein there is no sensing the disconnection of the power cord of the object.
310.01 for signal over power line.

SEE OR SEARCH CLASS:
174, Electricity: Conductors and Insulators, appropriate subclasses for power conductor or cable, per se.

Specified connector (e.g., phone jack-type plug):
This subclass is indented under subclass 568.2. Subject matter having a particular physical means of connection between the signal-carrying conduit and either the sensor or the article.

SEE OR SEARCH CLASS:
439, Electrical Connectors, appropriate subclasses for power connector, per se.

Shopping cart or item thereon:
This subclass is indented under subclass 568.1. Subject matter wherein the article being placed or removed is (a) a small-wheeled vehicle to carry merchandise or goods, or (b) any object carried by the small-wheeled vehicle.

SEE OR SEARCH CLASS:
280, Land Vehicles, appropriate subclasses for wheeled vehicle mechanism, per se.
473, Games Using Tangible Projectile, appropriate subclasses for article of recreational activity, such as golf or bowling ball, etc.

Currency, credit card, or container therefor (e.g., wallet or handbag):
This subclass is indented under subclass 568.1. Subject matter wherein the article being placed or removed is (a) a means which can be used for buying goods, or (b) its holder.

SEE OR SEARCH CLASS:
150, Purses, Wallets, and Protective Covers,101 for purse or handbag with means to deter theft of contents (e.g., puzzling closure or secret compartment).

Article on pedestal, in display case, or mounted on wall (e.g., work of art):
This subclass is indented under subclass 568.1. Subject matter wherein the article being placed or removed is an object of display on its support.

Mailbox:
This subclass is indented under subclass 568.1. Subject matter wherein the protected area is a receptacle for mail.

SEE OR SEARCH CLASS:
232, Deposit and Collection Receptacles, subclasses 34-37 for similar subject matter claimed in combination with significant mailbox structure.

Drawer:
This subclass is indented under subclass 568.1. Subject matter where the protected area is a drawer.

SEE OR SEARCH CLASS:
200, Electricity: Circuit Makers and Breakers, subclass 61.61 for drawer operated switches.

Alarm on protected article:
This subclass is indented under subclass 568.1. Subject matter where the entire system is attached to the protected object (e.g., in handbag).

Detectable device on protected article (e.g., "tag"):
This subclass is indented under subclass 568.1. Subject matter where there is a means on the object of surveillance to which the system is responsive.
(1) Note. For example, a magnet detectable device is affixed to the protected article.
(2) Note. A loop of a sensing circuit may be contained in the power connection of an electric appliance.

SEE OR SEARCH CLASS:
70, Locks, subclass 57.1 for a means attaching a named anti-theft signaling device onto a protected article.

Specified relationship between field and detection frequencies (e.g., nth order harmonics):
This subclass is indented under subclass 572.1. Subject matter where the detection system generates an interrogation field at a particular frequency, and the device or tag generates a response at another frequency having a predetermined correlation to the field frequency.

Deactivatable by means other than mere removal:
This subclass is indented under subclass 572.1. Subject matter where the element in the device or tag which causes a response to be sent to the detector system can be inactivated without being removed.

Specified processing arrangement for detected signal:
This subclass is indented under subclass 572.1. Subject matter where the manner of handling the detected signal, which results in a determination of placement or removal, is specified.

Having tuned resonant circuit:
This subclass is indented under subclass 572.1. Subject matter where the device or tag has a circuit which is capable of adjusting to respond to a particular frequency wave.

SEE OR SEARCH CLASS:
334, Tuners, for tuners, per se.

Having "soft" magnetic element (e.g., Permalloy):
This subclass is indented under subclass 572.1. Subject matter where the device or tag includes an element having magnetic properties of high permeability and low coercivity.

Specified antenna structure:
This subclass is indented under subclass 572.1. Subject matter where the detector system or tag has a particular aerial wave collector structure for sending or receiving signals.

SEE OR SEARCH CLASS:
343, Communications: Radio Wave Antennas, for antennas, per se.

Specified device housing or attachment means:
This subclass is indented under subclass 572.1. Subject matter where the device or tag casing, support, or affixed element thereon, is specified.

Having means locking device to article:
This subclass is indented under subclass 572.8. Subject matter where the attachment means fastens the device to the article.

SEE OR SEARCH CLASS:
70, Locks, 1.5 for locks with attack-actuated defeating mechanisms.

Human or animal:
This subclass is indented under subclass 540. Subject matter responsive to the condition of a human being or an animal.
(1) Note. The location of a living being by a force incidental thereto is not a condition of the living being for purposes of this classification.

SEE OR SEARCH THIS CLASS, SUBCLASS:
541 for intrusion detection.
666 for detection of the location of a living being by the weight thereof.

SEE OR SEARCH CLASS:
27, Undertaking, subclass 31 for life signals which indicate that a supposedly dead person is alive.
600, Surgery, appropriate subclasses for a diagnostic instrument.

Nondomestic animal (e.g., for hunting, fishing, or repelling):
This subclass is indented under subclass 573.1. Subject matter wherein a wild animal is detected.
(1) Note: Detection may be associated with a means to repel an animal.

SEE OR SEARCH CLASS:
43, Fishing, Trapping, and Vermin Destroying, appropriate subclass.

Domestic animal training, monitoring, or controlling:
This subclass is indented under subclass 573.1. Subject matter responsive to a condition of a pre-designated animal capable of living near or about the human habitation for the purpose of training, monitoring, or controlling.

House arrest system, wandering, or wrong place:
This subclass is indented under subclass 573.1. Subject matter responsive when a specific, pre-designated person has left his proper location.

SEE OR SEARCH THIS CLASS, SUBCLASS:
541 for detecting entry or attempted entry by a living being (intruder) into a protected area is detected.

Incontinence or enuresis alarm:
This subclass is indented under subclass 573.1. Subject matter responsive to the condition of a person who is unable to restrain a bodily discharge (e.g., urine) voluntarily (e.g., bed wetting).

Water safety alarm:
This subclass is indented under subclass 573.1. Subject matter responsive to a person \'3ds falling or nearly falling into a dangerous body of water.

SEE OR SEARCH THIS CLASS, SUBCLASS:
568.1 for article placement or removal.

Posture alarm:
This subclass is indented under subclass 573.1. Subject matter responsive to an improper posture of a body.

Holdup:
This subclass is indented under subclass 573.1. Subject matter responsive to the raising of a person's arms above the level of his head.

SEE OR SEARCH CLASS:
43, Fishing, Trapping, and Vermin Destroying, subclass 59 for burglar traps.

Sleep:
This subclass is indented under subclass 573.1. Subject matter responsive to sleep.
(1) Note. This subclass includes, for example, sleep inhibiting alarms which wake a person up every time he has a tendency to drowse, and antisnore alarms.

Drive capability:
This subclass is indented under subclass 573.1. Subject matter responsive to the capability of a person to operate a vehicle; e.g., intoxication.

SEE OR SEARCH CLASS:
180, Motor Vehicles, subclass 272 for safety devices responsive to incapacitated operator.

Flame:
This subclass is indented under subclass 540. Subject matter wherein the detected condition is the presence or absence of a flame.

SEE OR SEARCH CLASS:
137, Fluid Handling, subclass 65 for a combustion failure fluid safety cutoff.
219, Electric Heating, subclass 248 for a heating device
combined with a sole plate-type pressure application means (e.g., a flatiron, etc.) including a condition-responsive indicator, subclass 445.1 for an exposed planar support surface for material to be heated (e.g., hot plate, etc.) including an indicator, or subclasses 446.1+ for an exposed planar support surface for material to be heated (e.g., hot plate, etc.) including a sensing means.
431, Combustion, subclass 13 for combustion with indicator.

By radiant energy:
This subclass is indented under subclass 577. Subject matter wherein the presence of a flame is detected by radiation emitted therefrom.

SEE OR SEARCH CLASS:
250, Radiant Energy, subclass 554 for prephotocell systems with a flame light source.

By ionization or conductivity:
This subclass is indented under subclass 577. Subject matter wherein the flame is detected by passage of current therethrough due to its ionizing properties.

SEE OR SEARCH THIS CLASS, SUBCLASS:
629 for ionization-type smoke detectors.

Ice formation:
This subclass is indented under subclass 540. Subject matter wherein the condition is a solidification of a liquid or gas.

SEE OR SEARCH THIS CLASS, SUBCLASS:
962 for ice formation detectors on aircraft.

Thermal:
This subclass is indented under subclass 580. Subject matter wherein the ice formation is detected by its temperature or its heat transfer properties, or other properties (e.g., conductivity) when the sensed area is heated.

SEE OR SEARCH CLASS:
62, Refrigeration, 125 with indicator or signal.

Vibratory:
This subclass is indented under subclass 580. Subject matter wherein the ice formation is detected by modification of vibratory energy; e.g., mechanically loading a vibrating sensor.

SEE OR SEARCH THIS CLASS, SUBCLASS:
615 for similar subject matter sensing the level of fluent material.

Photoelectric:
This subclass is indented under subclass 580. Subject matter wherein the ice formation is detected by modification of light incident on an electrical photo responsive device.

Thermal:
This subclass is indented under subclass 540. Subject matter wherein the condition is a predetermined level of heat or temperature.

SEE OR SEARCH THIS CLASS, SUBCLASS:
581 for the thermal detection of ice formation.
606 for flow rate detection by a heat responsive sensor.
622 for heat responsive detection of liquid level.

SEE OR SEARCH CLASS:
116, Signals and Indicators, subclass 101 and 216+ for mechanical thermal alarms and indicators.
219, Electric Heating, subclass 248 for a heating device combined with a sole plate-type pressure application means (e.g., a flatiron, etc.) including a condition-responsive indicator, subclass 445.1 for an exposed planar support surface for material to be heated (e.g., hot plate, etc.) including an indicator, subclasses 446.1+ for an exposed planar support surface for material to be heated (e.g., hot plate, etc.) including a sensing means, or subclass 667 for a condition-responsive temperature load sensing power switching supply system for an inductive heating device.
329, Demodulators, appropriate subclasses for thermal change type demodulators.
331, Oscillators, subclass 66 for electric oscillation generators combined with condition sensing means responsive to temperature changes, and wherein some characteristic (e.g., wave amplitude or frequency) of the generator is varied by the condition sensing means.
356, Optics: Measuring and Testing, 43 for optical pyrometers.
361, Electricity: Electrical Systems and Devices, 161 for thermally responsive relay control circuit.
374, Thermal Measuring and Testing, subclasses 4-28 and 43 through 57 for thermal testing, subclasses 29+ for heat flux measurement, subclasses 31+ for a calorimeter; and subclasses 100+ for a thermometer with quantitative indication, particularly subclasses 121+ for a radiation thermometer.
431, Combustion, 13 for a burner having a signal or indicator; and subclasses 75+ for a burner controlled by a combustion zone sensor.

Refrigerated storage:
This subclass is indented under subclass 584. Subject matter wherein the monitored thermal condition is located interiorly of a refrigerated enclosure.

SEE OR SEARCH CLASS:
62, Refrigeration, 129 for a refrigeration system condition responsive indicator.

Portable:
This subclass is indented under subclass 584. Subject matter wherein the entire device including power supply is self-contained in a single housing, and of such size and weight to be transportable by a person.

False alarm resistant:
This subclass is indented under subclass 584. Subject matter wherein the device has provision to prevent an indication due to extraneous causes.

SEE OR SEARCH THIS CLASS, SUBCLASS:
529 for alarm systems having a time delay to permit indication only of a persistent condition.

Time-temperature relationship (e.g., overtemperature exceeds predetermined interval or time-temperature integral):
This subclass is indented under subclass 584. Subject matter where-in some time-temperature relationship (e.g., interval of overtemperature or time-temperature integral) exceeds or falls below a predetermined value.

SEE OR SEARCH THIS CLASS, SUBCLASS:
588 for an alarm having a time-delay circuit to indicate a persistent condition.

Rate of temperature change:
This subclass is indented under subclass 588. Subject matter wherein the time-temperature relationship is the time rate of change of the temperature.

Fusible, frangible, or destructible sensor:
This subclass is indented under subclass 584. Subject matter
wherein the temperature or heat condition causes the fusing or destruction of at least a portion of the temperature sensor.

SEE OR SEARCH THIS CLASS, SUBCLASS:
577 for a flame detecting device having a portion destroyed by flame.

SEE OR SEARCH CLASS:
337, Electricity: Electrothermally or Thermally Actuated Switches, 401 for a thermally actuated switch with fusible, combustible, or explosive material.
374, Thermal Measuring and Testing, subclass 106 and 160 for fusible thermometers.

Containing pressurized fluid:
This subclass is indented under subclass 590. Subject matter wherein the sensor contains fluid under a pressure higher than that of the ambient so as to produce a pressure drop upon destruction of the sensor element.

SEE OR SEARCH THIS CLASS, SUBCLASS:
626 for a pressure responsive indicator, per se.

SEE OR SEARCH CLASS:
169, Fire Extinguishers, 56 having various fusible and frangible condition responsive controls.
239, Fluid Sprinkling, Spraying, and Diffusing, subclass 71 for sprinkling systems with indicators.

Expanding fluid sensor:
This subclass is indented under subclass 584. Subject matter wherein the thermal condition is sensed by the expansion of a given mass of fluid.
(1) Note. The expansion may be sensed by an increase in either pressure or volume.

SEE OR SEARCH CLASS:
337, Electricity: Electrothermally or Thermally Actuated
Switches, 306 for an expanding fluid actuated thermally responsive switch.
374, Thermal Measuring and Testing, 201 for an expanding fluid thermometer.

Switch sensor:
This subclass is indented under subclass 584. Subject matter wherein the sensor includes a mechanical element movable in response to the thermal condition and which element makes or breaks an electric circuit.

SEE OR SEARCH CLASS:
337, Electricity: Electrothermally or Thermally Actuated Switches, 382 for a thermally actuated switch with a longitudinally expansible solid element.
374, Thermal Measuring and Testing, 187 for an expanding solid actuated thermometer.

With bimetallic element:
This subclass is indented under subclass 593. Subject matter wherein the mechanical element is, or is moved by, an element formed of two joined materials having different coefficients of thermal expansion.

SEE OR SEARCH CLASS:
337, Electricity: Electrothermally or Thermally Actuated Switches, 333 for a thermally actuated switch with a bimetallic element.
374, Thermal Measuring and Testing, 205 for a thermometer having a bimetallic element.

Current modifier or generator:
This subclass is indented under subclass 584. Subject matter wherein the thermal condition is detected by a sensor effecting a thermally responsive modification or generation of electric current in a circuit.

SEE OR SEARCH CLASS:
136, Batteries: Thermoelectric and Photoelectric, 200 for thermoelectric elements, per se.
338, Electrical Resistors, 25 for temperature-responsive resistors, per se.
361, Electricity: Electrical Systems and Devices, subclass 282 for thermally variable capacitors, per se.
374, Thermal Measuring and Testing, 163 for a thermometer with an electric sensor, particularly subclasses 179+ for a thermoelectric sensor thermometer, and subclasses 183+ for a current modifying sensor thermometer.

Cable or elongated probe:
This subclass is indented under subclass 595. Subject matter wherein the sensor is in the form of a current carrying cable or a probe sensing the thermal condition over its length which is large compared to its other dimensions.
(1) Note. Cable-type sensors are frequently utilized to determine the presence of an overtemperature condition in any of a plurality of zones monitored thereby.

SEE OR SEARCH THIS CLASS, SUBCLASS:
517 for a system with plural sensors in plural zones with a particular relationship therebetween.

Curie point sensor:
This subclass is indented under subclass 595. Subject matter wherein the sensor has a spontaneous ferroelectric or ferromagnetic polarization at some temperature, and detects thermal conditions by the change or disappearance of such polarization due to said conditions.

SEE OR SEARCH CLASS:
374, Thermal Measuring and Testing, 176 for a thermometer with a sensor having spontaneous polarization (e.g., ferroelectric, ferromagnetic).

Barrier-layer sensor:
This subclass is indented under subclass 595. Subject matter wherein the sensor is composed of semiconductor material and has a barrier layer therein.

SEE OR SEARCH CLASS:
257, Active Solid-State Devices (e.g., Transistors, Solid-State Diodes), subclasses 53-56, 108, 414, and 467 through 470 for such devices used as temperature sensors.
374, Thermal Measuring and Testing, subclass 178 for a thermometer having a semiconductor junction device sensing element.

Bridge circuit:
This subclass is indented under subclass 595. Subject matter wherein the sensor is part of a bridge circuit.

SEE OR SEARCH CLASS:
323, Electricity: Power Supply or Regulation Systems, subclass 365 for a Wheatstone bridge.

Radiant energy:
This subclass is indented under subclass 540. Subject matter wherein the condition is a predetermined level of radiation.

SEE OR SEARCH THIS CLASS, SUBCLASS:
578 for flame detection using radiant energy.
584 for detecting heat levels by thermally emitted radiant energy.

SEE OR SEARCH CLASS:
219, Electric Heating, subclass 248 for a heating device combined with a sole plate-type pressure application means (e.g., a flatiron, etc.) including a condition-responsive indicator, subclass 445.1 for an exposed planar support surface for material to be heated (e.g., hot plate, etc.) including an indicator, or subclasses 446.1+ for an exposed planar support surface for material to be heated (e.g., hot plate, etc.) including a sensing means.
250, Radiant Energy, 336.1 for invisible radiant energy responsive electric signalling; and subclasses 200+ for photocell circuitry.
356, Optics: Measuring and Testing, 219 for photoelectric photometers.

Meteorological condition:
This subclass is indented under subclass 540. Subject matter wherein the condition is an atmospheric phenomenon.

SEE OR SEARCH THIS CLASS, SUBCLASS:
584 for a similar device monitoring temperature.

SEE OR SEARCH CLASS:
73, Measuring and Testing, 170.16 for measurement of meteorological conditions.

Moisture or humidity (e.g., rain):
This subclass is indented under subclass 601. Subject matter wherein the meteorological condition is the presence of a predetermined amount of water or water vapor.
(1) Note. Dew point alarm systems are classified herein.

SEE OR SEARCH CLASS:
73, Measuring and Testing, subclass 170.17 for a rain gauge; and subclasses 335.08+ for a humidity measuring device.

Fluent material:
This subclass is indented under subclass 540. Subject matter wherein the monitored condition is a condition or characteristic of flowable material.

SEE OR SEARCH CLASS:
137, Fluid Handling, 551 for this subject matter combined with specific fluid handling structure.
239, Fluid Sprinkling, Spraying, and Diffusing, 71 for such subject matter particularly described and combined with a signal or indicator.

Wetness:
This subclass is indented under subclass 603. Subject matter responsive to the presence of water or water vapor.
(1) Note. The water or vapor may be entrained in a solid, flowable material, or another liquid.

SEE OR SEARCH THIS CLASS, SUBCLASS:
602 for such water detection as, or as related to, a meteorological condition.
603 for an alarm system responsive to a liquid contaminant other than water.

SEE OR SEARCH CLASS:
73, Measuring and Testing, 73 for measurement of the moisture content of material.
324, Electricity: Measuring and Testing, 664 and 694+ for moisture content measurement by capacitance and resistance, respectively.

Leakage:
This subclass is indented under subclass 603. Subject matter wherein the monitored condition of the fluent material is the escape thereof from a specified containing device.

SEE OR SEARCH CLASS:
73, Measuring and Testing, 40 for testing for leakage with fluid pressure.
374, Thermal Measuring and Testing, 4 for making a thermal test for leakage.

Flow rate:
This subclass is indented under subclass 603. Subject matter wherein the monitored condition is the amount of material flowing past a point in a given time interval.

SEE OR SEARCH CLASS:
116, Signals and Indicators, subclass 112 and 264+ for mechanical fluid flow alarms and indicators, respectively.
137, Fluid Handling, 551 for similar devices combined with significant fluid handling structure.

Filter clogging:
This subclass is indented under subclass 606. Subject matter wherein the flow is monitored to indicate blockage of a filter in the flow path.

SEE OR SEARCH THIS CLASS, SUBCLASS:
608 for flow stoppage indication in general.

SEE OR SEARCH CLASS:
210, Liquid Purification or Separation, 85 for matter of that class combined with alarm or signal means.

Stoppage:
This subclass is indented under subclass 606. Subject matter wherein the predetermined condition indicated is the cessation of the monitored flow.

SEE OR SEARCH CLASS:
137, Fluid Handling, 551 for indicator or alarm in a fluid handling system.

Counting:
This subclass is indented under subclass 606. Subject matter wherein the flow rate is determined by counting individual units of the fluent material (i.e., bubbles, drops, and particles).

SEE OR SEARCH CLASS:
377, Electrical Pulse Counters, Pulse Dividers, or Shift Registers: Circuits and Systems, subclass 21 for fluid parameter counters with indicators.

Vane in flow path:
This subclass is indented under subclass 606. Subject matter wherein the flow is sensed by the deflection of a solid element which extends transversely through the flow path.

Pressure:
This subclass is indented under subclass 606. Subject matter wherein the flow rate is detected by monitoring a pressure related thereto.
(1) Note. The monitored pressure may be a pressure difference.

SEE OR SEARCH THIS CLASS, SUBCLASS:
626 for monitoring pressure in general.

Material level:
This subclass is indented under subclass 603. Subject matter wherein the monitored conditions is the height of the material with respect to a reference position.

SEE OR SEARCH CLASS:
73, Measuring and Testing, 290 for measurement of liquid or dry fluent material level.
164, Metal Founding, 155.2 for a metal casting apparatus including control means responsive to material level.
200, Electricity: Circuit Makers and Breakers, 61.2 for level responsive switch, per se.

Weight in container:
This subclass is indented under subclass 612. Subject matter wherein the material level is sensed by a force sensor responsive to the weight of material in a container.

SEE OR SEARCH THIS CLASS, SUBCLASS:
666 for weight responsive alarm systems, in general.

Pressure:
This subclass is indented under subclass 612. Subject matter wherein the level is sensed by the pressure exerted by a fluid on a sensor, and includes differential pressure sensed by plural sensors.

SEE OR SEARCH THIS CLASS, SUBCLASS:
626 for pressure monitoring of general utility.

SEE OR SEARCH CLASS:
73, Measuring and Testing, 299 for liquid level measurement by pressure head measurement.

Moving sensor (e.g., impeller):
This subclass is indented under subclass 612. Subject matter wherein the presence or absence of material at the sensor is detected by the affect (e.g., damping) of the material on the motion of the sensor.
(1) Note. The term "motion" used above is also intended to encompass vibration of low amplitude.
(2) Note. The sensor is often an impeller.

SEE OR SEARCH THIS CLASS, SUBCLASS:
582 for a vibratory ice condition sensor.

Overflow:
This subclass is indented under subclass 612. Subject matter wherein the level is detected by overflowing of a full container, or of flow in an overflow discharge form a container.
(1) Note. The mere use of the term "overflow" does not automatically result in classification herein.

Pulverant material (e.g., bin):
This subclass is indented under subclass 612. Subject matter wherein the fluent material is a granular or powdered solid.
(1) Note. The solid material is often in a bin or similar receptacle.

SEE OR SEARCH CLASS:
73, Measuring and Testing, 290 for pulverant material measurement, as set forth in (3) Note.

Liquid:
This subclass is indented under subclass 612. Subject matter wherein the fluent material is a liquid.

SEE OR SEARCH CLASS:
73, Measuring and Testing, 290 for liquid level measurement.
137, Fluid Handling, subclass 392 for a liquid level responsive system sensing an electrical characteristic.

Optical sensor:
This subclass is indented under subclass 618. Subject matter wherein the liquid level is detected by a device responsive to or conducting light rays.

SEE OR SEARCH CLASS:
250, Radiant Energy, 564 and 577 for a prephotocell or optical system responsive to liquid level, but not including
a claimed indicating means.

Electrode probe:
This subclass is indented under subclass 618. Subject matter having a sensor containing one or more conductive elements for passing current through the liquid.
(1) Note. Such current includes displacement current of a capacitive arrangement.

SEE OR SEARCH CLASS:
73, Measuring and Testing, subclass 304 for similar sensors in liquid level measuring circuits.
338, Electrical Resistors, subclass 38 for resistive level sensors, per se.
361, Electricity: Electrical Systems and Devices, subclass 284 for capacitive level sensors, per se.

Having sonic sensor:
This subclass is indented under subclass 618. Subject matter wherein the liquid level is detected by a vibration responsive element, which may include a vibration transmitting element.

SEE OR SEARCH CLASS:
73, Measuring and Testing, subclass 290 for vibratory type liquid level measuring devices.
310, Electrical Generator or Motor Structure, 311 for piezoelectric vibration transducers, per se.
367, Communications, Electrical: Acoustic Wave Systems and Devices, 99 for liquid level measuring means.

Having heat sensor:
This subclass is indented under subclass 618. Subject matter wherein the liquid level is detected by a thermally responsive sensor.

SEE OR SEARCH CLASS:
122, Liquid Heaters and Vaporizers, subclass 504.2 for boiler alarm or indicator thermally responsive to steam when water level falls below a certain limit.

Float sensor:
This subclass is indented under subclass 618. Subject matter wherein the liquid level is sensed by the position of a buoyant object floating on the liquid surface.

SEE OR SEARCH CLASS:
73, Measuring and Testing, subclass 308 for the combination of a float-type liquid level measuring device and an electrical signal or alarm.
200, Electricity: Circuit Makers and Breaker, subclass 84 for float actuated switches.

Vertically reciprocable:
This subclass is indented under subclass 623. Subject matter wherein the float has no horizontal component of motion.

SEE OR SEARCH CLASS:
73, Measuring and Testing, subclass 319 for a vertically reciprocable float operated liquid level measuring device.

Pivoted arm:
This subclass is indented under subclass 623. Subject matter wherein the float is rigidly attached to an arm connected to a pivot so as to restrict the motion of the float to an arcuate path centered at the pivot.

SEE OR SEARCH CLASS:
73, Measuring and Testing, 317 for a pivoted float arm operated liquid level measuring device.

Pressure:
This subclass is indented under subclass 603. Subject matter wherein the monitored condition is the pressure of the fluent material.

SEE OR SEARCH CLASS:
73, Measuring and Testing, 700 for fluid pressure gauges.
200, Electricity: Circuit Makers and Breakers, 81 for pressure responsive switches.

Particle suspension in fluid:
This subclass is indented under subclass 603. Subject matter wherein the fluent material has particulate matter entrained therein.

SEE OR SEARCH CLASS:
73, Measuring and Testing, subclass 23.33 for gas analysis for solid matter; and subclasses 53.01+ for measuring particles in a liquid suspension.
356, Optics: Measuring and Testing, 441 for an optical transmission or absorption liquid particle suspension measuring device.

Smoke:
This subclass is indented under subclass 627. Subject matter wherein particle suspension is in a gas, and is generally the result of combustion.

SEE OR SEARCH THIS CLASS, SUBCLASS:
577 for the detection of a flame.
584 for the detection of smoke by the thermal properties thereof.

SEE OR SEARCH CLASS:
200, Electricity: Circuit Makers and Breakers, subclass 61.03 for a smoke operated switch.

Ionization:
This subclass is indented under subclass 628. Subject matter wherein the smoke detector responds to ionization of the smoke caused by an applied electric field or a radioactive source.

SEE OR SEARCH CLASS:
250, Radiant Energy, subclass 381 for ionization-type signalling circuits, per se.

Photoelectric:
This subclass is indented under subclass 628. Subject matter wherein the sensor is a photodetector responsive to the optical properties of smoke.

SEE OR SEARCH CLASS:
250, Radiant Energy, 573.1 for photocell actuated, fluent material detecting circuit.
356, Optics: Measuring and Testing, 438 for an optical transmission or absorption smoke measuring device.

Lubricant:
This subclass is indented under subclass 627. Subject matter wherein the particle suspension is in, or of, a lubricating liquid for a mechanical device.

SEE OR SEARCH THIS CLASS, SUBCLASS:
682 for bearing condition in general.

SEE OR SEARCH CLASS:
73, Measuring and Testing, subclass 53.05 for lubricant testing.

Gas:
This subclass is indented under subclass 603. Subject matter wherein the fluent material is a gas.

SEE OR SEARCH CLASS:
73, Measuring and Testing, 23.2 for gas analysis.
200, Electricity: Circuit Makers and Breakers, subclass 61.03 for a gas operated switch.
356, Optics: Measuring and Testing, 213 and 300+ for spectroscopy and photometers respectively.

Catalytic detector:
This subclass is indented under subclass 632. Subject matter wherein the gas sensor includes a catalyst to induce a chemical reaction producing a parameter to which the sensor is responsive (e.g., heat).
(1) Note. The sensor is often coated with the catalyst and is thermally responsive.

SEE OR SEARCH CLASS:
422, Chemical Apparatus and Process Disinfecting, Deodorizing, Preserving, or Sterilizing, 83 for gas analysis apparatus utilizing a chemical reaction.
436, Chemistry: Analytical and Immunological Testing, 68 for gas analysis utilizing a chemical reaction.

Semiconductor detector:
This subclass is indented under subclass 632. Subject matter wherein the detector is composed of material having an electrical conductivity between that of metals and that of insulators, and which conductivity increases in the presence of a sensed gas.
(1) Note. The sensor may include a heating element to raise its temperature to the appropriate operating range.

SEE OR SEARCH CLASS:
338, Electrical Resistors, subclass 34 for a gas responsive
resistor.

Condition of electrical apparatus:
This subclass is indented under subclass 540. Subject matter wherein the monitored condition is an electrical property of a specific electrical device or circuit.

SEE OR SEARCH THIS CLASS, SUBCLASS:
506 for an electrical alarm circuit or element, the integrity of which is monitored.
584 for monitoring the thermal characteristics of electrical devices.
657 for characteristics of electricity, per se, not representative of the condition of a particular device.

SEE OR SEARCH CLASS:
219, Electric Heating, subclass 248 for a heating device combined with a sole plate-type pressure application means (e.g., a flatiron, etc.) including a condition-responsive indicator, subclass 445.1 for an exposed planar support surface for material to be heated (e.g., hot plate, etc.) including an indicator, subclasses 446.1+ for an exposed planar support surface for material to be heated (e.g., hot plate, etc.) including a sensing means, or subclass 506 for a heating device having automatic regulating or control of power supply and voltage including signal or indicator means.
324, Electricity: Measuring and Testing, 403 for testing of electric lamp or discharge devices; and subclasses 415+ for the testing of electromechanical switching devices.

Battery:
This subclass is indented under subclass 635. Subject matter where the device is a battery.

SEE OR SEARCH CLASS:
320, Electricity: Battery or Capacitor Charging or Discharging, appropriate subclass for a battery or capacitor charging or discharging circuit combined with an indicator.
429, Chemistry: Electrical Current Producing Apparatus,
Product, and Process, 90 for testing and indicating where specific battery structure is claimed.

Watt-hour meter:
This subclass is indented under subclass 635. Subject matter where the monitored device is a watt-hour meter.
(1) Note. This subclass pertains to a meter condition, not power consumption, per se.

SEE OR SEARCH CLASS:
324, Electricity: Measuring and Testing, subclass 74 for testing watt-hour meters.

Fuse or circuit breaker:
This subclass is indented under subclass 635. Subject matter where the device is current level responsive circuit interrupting device.

SEE OR SEARCH CLASS:
324, Electricity: Measuring and Testing, 424 for the testing of circuit breakers.
335, Electricity: Magnetically Operated Switches, Magnets, and Electromagnets, subclass 17 for electromagnetic circuit breakers with integral signalling, indicating, or alarm means.
337, Electricity: Electrothermally or Thermally Actuated Switches, subclass 206 for fusible element actuated switches with integral indicator; subclass 241 for cartridge fuses with integral indicators; and subclass 265 for plug fuses with integral indicators.

Plural:
This subclass is indented under subclass 638. Subject matter where plural fuses or circuit breakers are monitored.

Heater element:
This subclass is indented under subclass 635. Subject matter where the monitored device is an electric heating element.

SEE OR SEARCH THIS CLASS, SUBCLASS:
584 for monitoring the thermal condition of an electric heater.

SEE OR SEARCH CLASS:
219, Electric Heating, subclass 248 for a heating device combined with a sole plate-type pressure application means (e.g., a flatiron, etc.) including a condition-responsive indicator, subclass 269 for an igniter-type resistive element indicating means, subclass 445.1 for an exposed planar support surface for material to be heated (e.g., hot plate, etc.) including an indicator, subclasses 446.1+ for an exposed planar support surface for material to be heated (e.g., hot plate, etc.) including a sensing means, subclass 487 for a heating device having a power supply and voltage or current regulation or current control means to control or regulate plural separate distinct heating resistance elements (i.e., one control system for all elements, etc.) selectively, sequentially, or alternately including indicator means, or subclass 506 for a heating device having a power supply with automatic regulation of its voltage or current including signal or indicator means.

Signalling light element:
This subclass is indented under subclass 635. Subject matter wherein the monitored device is an electric signalling light.
(1) Note. Any claimed signalling function is sufficient for classification herein.

SEE OR SEARCH THIS CLASS, SUBCLASS:
458 for a light monitoring system in a specified vehicle.

SEE OR SEARCH CLASS:
315, Electric Lamp and Discharge Devices: Systems, 88 for automatic filament substitution; subclass 120 for a nonsignalling lamp system having an indicator and an automatic shunt or cut-out; and subclasses 129+ for a nonsignalling; e.g., illuminating, lamp system with indicators.
324, Electricity: Measuring and Testing, subclass 403 for lamp testing.

Plural bulbs or filaments:
This subclass is indented under subclass 641. Subject matter where plural lights are monitored.

Thermal or magnetic current sensors:
This subclass is indented under subclass 641. Subject matter where the condition of the light is sensed by means responsive to the thermal or magnetic effects of current flow through a conductor connected to the light being monitored.

Switch or relay:
This subclass is indented under subclass 635. Subject matter wherein the monitored device is a circuit interrupter, and may be manually or automatically actuated.

SEE OR SEARCH THIS CLASS, SUBCLASS:
286.04 for a manually actuated switch con-trolled alarm system.
540 for switch-type sensors actuated in response to a specified condition and placed in an alarm or indicator circuit.
638 for monitoring a circuit breaker.

SEE OR SEARCH CLASS:
200, Electricity: Circuit Makers and Breakers, subclass 312 for significant switch structure combined with an indicator for its condition.
307, Electrical Transmission or Interconnection Systems, 116 for condition responsive switching systems.
324, Electricity: Measuring and Testing, 415 for contact, relay, and switch testing.
327, Miscellaneous Active Electrical Nonlinear Devices, Circuits, and Systems, appropriate subclasses for miscellaneous signal systems.
335, Electricity: Magnetically Operated Switches, Magnets, and Electromagnets, subclass 17 for significant relay structure combined with indicator for its condition.
361, Electricity: Electrical Systems and Devices, 139 for a relay control circuit.

Rectifier:
This subclass is indented under subclass 635. Subject matter wherein the monitored device is a rectifier or a plurality of rectifiers.

SEE OR SEARCH CLASS:
327, Miscellaneous Active Electrical Nonlinear Devices, Circuits, and Systems, appropriate subclasses for miscellaneous circuits which may include a rectifier.
363, Electric Power Conversion Systems, appropriate subclasses for the details of rectification systems.

Transformer:
This subclass is indented under subclass 635. Subject matter where the monitored device is a transformer.

SEE OR SEARCH THIS CLASS, SUBCLASS:
584 for alarms responsive to thermal condition of a transformer.

SEE OR SEARCH CLASS:
324, Electricity: Measuring and Testing, subclass 726 for transformer testing.
361, Electricity: Electrical Systems and Devices, 35 for transformer safety systems and subclass 93.6 for abnormal current condition detection using transformer sensor.

Insulation:
This subclass is indented under subclass 635. Subject matter where the monitored device is electrical insulation.

SEE OR SEARCH CLASS:
324, Electricity: Measuring and Testing, subclass 541 for insulation testing.

Motor:
This subclass is indented under subclass 635. Subject matter where the monitored device is an electric motor.

SEE OR SEARCH CLASS:
318, Electricity: Motive Power Systems, subclass 490 for similar subject matter combined with motor control systems.

Condition of intentional grounding circuit:
This subclass is indented under subclass 635. Subject matter where the monitored device is an intentional grounding circuit, (i.e., a protective ground).

SEE OR SEARCH CLASS:
324, Electricity: Measuring and Testing, 500 for circuit fault testing.
361, Electricity: Electrical Systems and Devices, 42 for ground fault protection systems.

Undesired circuit ground or short:
This subclass is indented under subclass 635. Subject matter where the condition monitored is an unwanted grounding or short circuiting of a power or signal conductor.

SEE OR SEARCH CLASS:
324, Electricity: Measuring and Testing, 509 for circuit grounding detectors that are used for occasional testing as distinguished from continuously monitoring for an alarm
condition.

For plural circuit conductors:
This subclass is indented under subclass 650. Subject matter where plural conductors are monitored.

Breaking of circuit continuity:
This subclass is indented under subclass 635. Subject matter where the condition monitored is the integrity of a circuit; e.g., power or communication lines.

SEE OR SEARCH THIS CLASS, SUBCLASS:
506 for monitoring alarm circuit continuity.
649 for ground circuit continuity alarm.

SEE OR SEARCH CLASS:
324, Electricity: Measuring and Testing, 539 for circuit continuity testing as distinguished from continuously monitoring for an alarm condition.

Electronic circuit or component:
This subclass is indented under subclass 635. Subject matter where the device is an active electronic circuit or component; e.g., amplifier, vacuum tube, or transistor.
(1) Note. Significant art structure with indicating device will classify claimed subject matter with art structure as pointed out in (2) Note of the general class definitions of this class (340).

SEE OR SEARCH THIS CLASS, SUBCLASS:
654 for monitoring of energization of a component.

SEE OR SEARCH CLASS:
330, Amplifiers, subclass 2 for amplifiers with indicating means.
331, Oscillators, subclass 64 for oscillators with alarms.
377, Electrical Pulse Counters, Pulse Dividers, or Shift Registers: Circuits and Systems, 112 for electrically operated registers with indicators.

Circuit energization:
This subclass is indented under subclass 635. Subject matter where the condition monitored is the state of power energization of a circuit (e.g., off or on).
(1) Note. Nominal recitation of a pilot light in an art device will not be classified herein.

Heating circuit:
This subclass is indented under subclass 654. Subject matter where the monitored circuit includes an electric heater.

SEE OR SEARCH THIS CLASS, SUBCLASS:
640 for monitoring the condition of a heater element.

SEE OR SEARCH CLASS:
219, Electric Heating, subclass 109 for a current supply indicator (e.g., a recorder, etc.) to a metal heating (e.g., resistance heating, etc.) pressure bonding (e.g., resistance welding, etc.) apparatus, subclass 248 for a heating device combined with a sole plate-type pressure application means (e.g., a flatiron, etc.) including a condition-responsive indicator, subclass 445.1 for an exposed planar support surface for material to be heated (e.g., hot plate, etc.) including an indicator, subclasses 446.1+ for an exposed planar support surface for material to be heated (e.g., hot plate, etc.) including a sensing means, subclass 487 for a heating device having a power supply and voltage or current regulation or current control means to control or regulate plural separate distinct heating resistance elements (i.e., one control system for all elements, etc.) selectively, sequentially, or alternately including indicator means, or subclass 506 for a heating device having automatic regulating or control means of power supply and voltage including signal or indicator means.

Electrical socket:
This subclass is indented under subclass 654. Subject matter where the circuit is monitored at an electrical socket and the condition may be whether the socket or load plugged into the socket is energized.

SEE OR SEARCH THIS CLASS, SUBCLASS:
687 for indication of mechanical connection of electrical connectors.

SEE OR SEARCH CLASS:
324, Electricity: Measuring and Testing, subclass 133 for testing devices for polarity and hot-line indication.
439, Electrical Connectors, 488 for an electrical connector combined with an indicating or identifying means.

Electrical characteristic:
This subclass is indented under subclass 540. Subject matter where the condition monitored is a characteristic of electricity, per se, (i.e., power delivered, electric charge), rather than of a particular circuit.

SEE OR SEARCH CLASS:
307, Electrical Transmission or Interconnection Systems, 125 for switching systems that are responsive to electrical conditions.
324, Electricity: Measuring and Testing, 76.11 for measuring, testing, or sensing electricity, per se.
327, Miscellaneous Active Electrical Nonlinear Devices, Circuits, and Systems, 1 for miscellaneous discriminating circuits.
361, Electricity: Electrical Systems and Devices, 182 for relay systems that are electrical characteristic responsive.

Phase or frequency:
This subclass is indented under subclass 657. Subject matter where the monitored characteristic is electrical phase or frequency.

SEE OR SEARCH CLASS:
324, Electricity: Measuring and Testing, 76.39 and 76.77+ for frequency and phase measurement, respectively.

Pulse or surge:
This subclass is indented under subclass 657. Subject matter where the monitored characteristic is the occurrence of an electrical pulse or surge (i.e., pulse occurrence or absence, width, lightning stroke).

SEE OR SEARCH CLASS:
324, Electricity: Measuring and Testing, 72 for testing potential in a specific environment (e.g., lightning stroke).

Voltage:
This subclass is indented under subclass 657. Subject matter where the monitored characteristic is the electrical potential at a point in a current carrying circuit.

SEE OR SEARCH CLASS:
324, Electricity: Measuring and Testing, subclass 72.5 for a voltage probe in a specific environment; subclasses 76.11+ for voltage measurement absent a significant tangible environment, and particularly subclass 133 for a test with a nonquantitative indication.

Comparison:
This subclass is indented under subclass 660. Subject matter where the voltage is monitored by comparison with another voltage or a reference.

SEE OR SEARCH CLASS:
327, Miscellaneous Active Electrical Nonlinear Devices, Circuits, and Systems, 50 for miscellaneous specific amplitude discriminating circuits.

Overvoltage:
This subclass is indented under subclass 660. Subject matter where the voltage exceeds a specified level.

Undervoltage:
This subclass is indented under subclass 660. Subject matter where the voltage falls below a specified level.

Current:
This subclass is indented under subclass 657. Subject matter where the sensed characteristic is the rate of flow of electrical charge with respect to time.

SEE OR SEARCH CLASS:
324, Electricity: Measuring and Testing, 76.11 for current measurement and testing absent a significant tangible environment, and particularly subclass 133 for a nonquantitative indication.

Force or stress:
This subclass is indented under subclass 540. Subject matter where the condition is a mechanical force or stress.

SEE OR SEARCH CLASS:
73, Measuring and Testing, 760 for stress measurement; and subclasses 862.381+ for force measurement.

Weight:
This subclass is indented under subclass 665. Subject matter where the force is gravitationally induced.

SEE OR SEARCH CLASS:
177, Weighing Scales, 45 for alarms on scales.
200, Electricity: Circuit Makers and Breakers, 85 for weight sensing switches.

On seat:
This subclass is indented under subclass 666. Subject matter wherein the sensor responds to weight upon the weight bearing surface of a seat.

SEE OR SEARCH THIS CLASS, SUBCLASS:
438 and 457.1, for this subject matter in a vehicle.

Tension:
This subclass is indented under subclass 665. Subject matter where the force exists in tension.

SEE OR SEARCH CLASS:
43, Fishing, Trapping, and Vermin Destroying, subclass 17 for indicating tension as the result of a fish being hooked on a fishing line.
73, Measuring and Testing, subclass 761 for fastener stress.
242, Winding, Tensioning, or Guiding, subclass 357, 472.0+, 479.9+, 484.8, 484.9+, 534+, 563+, and 912 for a detector, signal, or indicator associated with winding or unwinding an elongated material, which material is frequently under a tension control, and subclasses 410+ for regulating tension in a running length of elongated material.

Acceleration:
This subclass is indented under subclass 540. Subject matter wherein the sensed condition is a change in velocity with respect to time.

SEE OR SEARCH THIS CLASS, SUBCLASS:
429 436 and 463, for acceleration responsive signalling systems in vehicles.

SEE OR SEARCH CLASS:
73, Measuring and Testing, subclass 488 for measurement of acceleration.
200, Electricity: Circuit Makers and Breakers, 61.45 for acceleration responsive switches.
324, Electricity: Measuring and Testing, subclass 162 for acceleration measuring means combined with electrical speed measurement.

Velocity:
Subject matter under 540 wherein the sensed condition is the change in position of a specified object with respect to time.

SEE OR SEARCH THIS CLASS, SUBCLASS:
441 and 463+, for a speed signalling system in a vehicle.

SEE OR SEARCH CLASS:
73, Measuring and Testing, 488 for speed measurement.
324, Electricity: Measuring and Testing, 160 for electrical speed measurement.

Angular:
This subclass is indented under subclass 670. Subject matter where the velocity is angular.

SEE OR SEARCH CLASS:
246, Railway Switches and Signals, subclass 168.1 for wheel slip indicators for rail locomotives.

Direction of shaft rotation:
This subclass is indented under subclass 671. Subject matter wherein the monitored angular velocity is characterized by direction of rotation of a shaft.

SEE OR SEARCH CLASS:
116, Signals and Indicators, 200 for a mechanical shaft rotation indicator.

Article transport:
This subclass is indented under subclass 540. Subject matter where the condition is of an object moving along a constrained path.

SEE OR SEARCH THIS CLASS, SUBCLASS:
933 for traffic detection and signalling systems.

SEE OR SEARCH CLASS:
198, Conveyors: Power-Driven, subclass 340 for signalling means at a station along a conveyor path; and subclass 502.01 for a conveyor or load alarm or indicator.

Discrete articles:
This subclass is indented under subclass 673. Subject matter where the object has discrete boundaries which pass the point at which the condition is observed.

SEE OR SEARCH CLASS:
250, Radiant Energy, subclass 222.1 for photocell circuits for detecting article passage.

Web, film, or strip:
This subclass is indented under subclass 673. Subject matter where the moving object is a continuous web, film, or strip.

SEE OR SEARCH CLASS:
73, Measuring and Testing, subclass 157 for film sprocket
hole testing; and subclasses 159+ for sheet, woven fabric, or fiber testing.
242, Winding, Tensioning, or Guiding, subclass 357, 472.0+, 479.9+, 484.8, 484.9+, 534+, and 563+ for a detector or stop associated with winding or unwinding an elongated material.
250, Radiant Energy, subclass 548 and 559.01+ for photocell circuits for detecting a web, strip, or sheet.

Conveyor belt:
This subclass is indented under subclass 675. Subject matter where the web is a conveyor belt.
(1) Note. This subclass relates to the condition of the conveyor belt, not to the articles thereupon.

Strand:
This subclass is indented under subclass 673. Subject matter where the object is a continuous strand (e.g., thread, rope, wire).

SEE OR SEARCH CLASS:
57, Textiles: Spinning, Twisting, and Twining, subclass 81 for stopping and starting control.
66, Textiles: Knitting, subclass 163 for strand stop control.
250, Radiant Energy, subclass 548 and 559.01+ for photocell circuits responsive to a web, strand, strip, or sheet.

Of geometrical gauge:
This subclass is indented under subclass 540. Subject matter where the condition is determined by monitoring the size or shape of an object.

SEE OR SEARCH CLASS:
33, Geometrical Instruments, appropriate subclasses for measuring or gauging means with electrical indicators.
73, Measuring and Testing, subclass 104 for surface or cutting edge testing.

Machine condition:
This subclass is indented under subclass 540. Subject matter wherein the monitored condition is that of a particular mechanical device or component thereof.

Machine tool:
This subclass is indented under subclass 679. Subject matter where the machine component monitored is a tool (e.g., drill bit or cutting tool).

SEE OR SEARCH CLASS:
173, Tool Driving or Impacting, 20 for a tool driving device with indicating or signalling means.

Synchronization:
This subclass is indented under subclass 679. Subject matter where the condition is synchronization between mechanisms.

SEE OR SEARCH CLASS:
307, Electrical Transmission or Interconnection Systems, subclass 87 for connecting plural supply circuits or sources at correct phase relationship.
318, Electricity: Motive Power Systems, subclass 85 for synchronizing motors.
324, Electricity: Measuring and Testing, 378 for ignition timing.
375, Pulse or Digital Communications, subclass 106 for synchronizers.

Bearing:
This subclass is indented under subclass 679. Subject matter where the machine component is a bearing.

SEE OR SEARCH THIS CLASS, SUBCLASS:
584 and 600, for temperature monitoring of bearings.
631 for bearing particles in oil.

Vibration:
This subclass is indented under subclass 679. Subject matter where the condition is a vibration.

SEE OR SEARCH THIS CLASS, SUBCLASS:
566 for intrusion vibration responsive systems.

SEE OR SEARCH CLASS:
73, Measuring and Testing, 570 for vibration measurement and testing.

Agricultural:
This subclass is indented under subclass 679. Subject matter where the machine is an agricultural machine.

SEE OR SEARCH CLASS:
56, Harvesters; 111, Planting; and 460, Crop Threshing or Separating, appropriate subclasses for detailed structure thereof.

Cranes:
This subclass is indented under subclass 679. Subject matter where the machine is a crane.

SEE OR SEARCH THIS CLASS, SUBCLASS:
668 for cable tension in cranes.

SEE OR SEARCH CLASS:
212, Traversing Hoists, 276 for automatic stop control for cranes, and other condition sensors which regulates an indicator, alarm, or controller. Class 212 takes condition responsive indicator systems claimed in combination with any structural details of a crane.

Position responsive:
This subclass is indented under subclass 540. Subject matter responsive to a standing point of one object relative to another.

SEE OR SEARCH CLASS:
137, Fluid Handling, 553 for a position or extent of motion indicator or alarm combined with a fluid handling means such as a valve.
219, Electric Heating, subclass 121.3 and 121.32 for nonalarm position responsive in metal heating by electron beam.
364, Electrical Computer and Data Processing Systems, 474.28 for computerized control of digital positioning of manufactured product or operation.

Alignment or misalignment:
This subclass is indented under subclass 686.1. Subject matter wherein indication is provided when two or more elements come into a relative position in (a) a precise adjusting, or (b) unprecise adjusting manner.

Shaft or rotary element:
This subclass is indented under subclass 686.1. Subject matter wherein an indication is provided when a particular point is reached along the circumference of a cylindrical bar which supports or transmits motion by rotation.

One article inserted into another:
This subclass is indented under subclass 686.1. Subject matter wherein two elements which normally interact by one being placed inside the other, and an indication is provided either in response to this occurrence or some particular condition of this occurrence (e.g., improper insertion).

Workpiece:
This subclass is indented under subclass 686.1. Subject matter including an element which is in the process of being manufactured, and wherein the indicating system monitors whether the element is in a proper position to be worked on.

SEE OR SEARCH CLASS:
219, Electric Heating, subclass 121.32 for nonalarm workpiece position responsive in metal heating by electron beam.
364, Electrical Computer and Data Processing Systems, 474.28 for a computer- controlled digital positioning technique.

Proximity or distance:
This subclass is indented under subclass 686.1. Subject matter responsive to an object coming too close to, or moving too far away from, another object.
(1) Note. This subclass requires that two objects maintain a predetermined maximum or minimum distance from each other.

SEE OR SEARCH CLASS:
327, Miscellaneous Active Electrical Nonlinear Devices, Circuits, and Systems, subclass 517 for generic transistor circuitry responsive to proximity or touch.

Connected or disconnected:
This subclass is indented under subclass 686.1. Subject matter responsive to the mechanical connection of two or more objects.
(1) Note. The system may, for example, be responsive to the mechanical connection of electrical connectors.

SEE OR SEARCH THIS CLASS, SUBCLASS:
431 for trailer signal light systems and hitch alignment devices.

SEE OR SEARCH CLASS:
200, Electricity: Circuit Makers and Breakers, 51 for connector actuated switches.
307, Electrical Transmission and Interconnection Systems, subclass 9.1 for vehicle-to-trailer electrical interconnection systems which may include an alarm or indicator of connection or disconnection.

Meter dial:
This subclass is indented under subclass 686.1. Subject matter responsive to the position of a pointer on a scale.
(1) Note. If the pointer is automatically responsive to a specified condition, the system will be found with measurement of the condition.

Tilt:
This subclass is indented under subclass 686.1. Subject matter responsive to the angular orientation of an object with respect of a predetermined reference orientation thereof.

SEE OR SEARCH THIS CLASS, SUBCLASS:
429 and 440, for vehicle alarms or indicators responsive to tilt of the vehicle.

SEE OR SEARCH CLASS:
33, Geometrical Instruments, subclass 366.11 for measuring levels with electrical indicators.
200, Electricity: Circuit Makers and Breakers, subclass 52 for tilting vehicle operated switches; and subclasses 61.45+ for tilt operated switches.

Geophysical (e.g., fault slip):
This subclass is indented under subclass 686.1. Subject matter responsive to the position of parts of the earth relative to other parts of the earth.
(1) Note. This subclass includes, for example, position of mine roofs, earthquake faults, etc.

SEE OR SEARCH THIS CLASS, SUBCLASS:
855.3 for signaling in a wellbore telemetering system.

SEE OR SEARCH CLASS:
73, Measuring and Testing, subclass 784 for earth stress measurement.
166, Wells, subclass 64 for a well with time or distance measuring or temperature responsive or counting means; and subclass 66 for a well with electrical indicating means.
175, Boring or Penetrating The Earth, 40 for such subject matter which is particularly described and combined with signalling or indicating means.
324, Electricity: Measuring and Testing, 323 for determining an electrical characteristic of the subsurface of the earth, in situ.
367, Communications, Electrical: Acoustic Wave Systems and Devices, subclass 81 for wellbore alarm systems.

Specified indicator structure:
This subclass is indented under subclass 500. Subject matter wherein the means translating electrical signals into humanly perceptible signals are particularly described.
(1) Note. Mere inclusion by name only is insufficient for classification herein; detailed structure or circuitry is necessary.
(2) Note. This subclass includes specific circuitry which provides the desired indication effects (e.g., pulsed or steady indication, bright or dim) as well as structure.

SEE OR SEARCH THIS CLASS, SUBCLASS:
384.1 407.1+, 815.4+, for audible, tactual, and visual indicators, respectively.

Simulated effect:
This subclass is indented under subclass 691.1. Subject matter where the humanly perceptible signal is intended to give the impression that a physical object is present when it actually isn't (e.g., "dummy" surveillance camera, or arrows providing direction to emergency exit).
(1) Note. For example, a set of visual indicators are actuated in sequence to indicate a direction, thereby "simulating" a means providing an escape route during events such as a fire.

SEE OR SEARCH THIS CLASS, SUBCLASS:
384.3 for audible indication simulation.
693.8 for specific housing simulation.

Degree or urgency:
This subclass is indented under subclass 691.1. Subject matter where multiple discrete stages or levels of a condition are monitored, and a different discrete humanly perceptible signal is provided for each stage or level.
(1) Note. For example, a "pre-alarm" warning vs. an all-out alarm.

SEE OR SEARCH THIS CLASS, SUBCLASS:
328 for a generic audible signaling system with degree or urgency.
691.4 for a condition responsive with plural indicating signals.

Plural:
This subclass is indented under subclass 691.1. Subject matter where the system provides more than one humanly perceptible indication in response to a single condition.
(1) Note. For example, multiple alarms in different rooms of a dwelling, each responsive to events such as intrusion or fire being sensed at any point in the dwelling.

SEE OR SEARCH THIS CLASS, SUBCLASS:
326 for a generic indicating system having plural concurrent single indications.
691.3 for a condition responsive indicating with multiple discrete human perceptible signals generated in different stages or levels.

Diverse:
This subclass is indented under subclass 691.4. Subject matter where at least two of the indications are of different types.
(1) Note. For example, visual and audible, continuous light and flashing light.

SEE OR SEARCH THIS CLASS, SUBCLASS:
326 for a system having plural concurrent single indications (e.g., light flashes when bell rings).
815.69 for a generic diverse indications.

Information display:
This subclass is indented under subclass 691.1. Subject matter where the humanly perceptible signal is a written message communicated via means such as an electronic sign or screen.
(1) Note. For example, a cathode ray tube (CRT) or a liquid crystal display (LCD) is included.

SEE OR SEARCH CLASS:
345, Computer Graphics Processing, Operator Interface Processing, and Selective Visual Display Systems, appropriate subclasses for processing and control of a display system.

Mechanical:
This subclass is indented under subclass 691.1. Subject matter where the humanly perceptible signal, while controlled by electrical means, is itself nonelectrical in nature.
(1) Note. For example, a deployable flag or balloon, or the release of fluent material is included.

SEE OR SEARCH THIS CLASS, SUBCLASS:
815.83 for a generic movable visual indication.

SEE OR SEARCH CLASS:
116, Signal and Indicators, appropriate subclasses for a mechanical indicator without electrical control circuitry.

Control circuit detail:
This subclass is indented under subclass 691.1. Subject matter wherein electronic components, or an arrangement thereof for actuating the indicator, is particularly described.

Sound reproducer:
This subclass is indented under subclass 691.1. Subject matter where the humanly perceptible signal is an audible message communicated via means such as a loudspeaker.

SEE OR SEARCH CLASS:
381, Electrical Audio Signal Processing and Systems, appropriate subclasses for audio systems in general.

Specified power supply:
This subclass is indented under subclass 500. Subject matter wherein either some portion of the energizing supply, or a function of the energizing supply in addition to energization, is particularly described.
(1) Note. Power supplies included by name only are not
classified herein.
(2) Note. The additional function referred to above is generally to cope with a particular problem, e.g., switching to an alternate power supply upon failure of the main power supply.

SEE OR SEARCH CLASS:
307, Electrical Transmission or Interconnection Systems,43 for plural supply circuits or sources for electrical transmission or interconnection in general.
327, Miscellaneous ActiveElectrical Nonlinear Devices, Circuits, or Systems,530 for a specific transistor circuitry source of supply or bias voltage.
361, Electricity: Electrical Systems and Devices,1 for a power supply with a safety feature; and subclasses 600+ for a housing having diverse electrical components.
363, Electric Power Conversion Systems, for power supply conversion (e.g., A.C. to D.C.), generally.

Substitute or emergency source (e.g. back-up battery):
This subclass is indented under subclass 693.1. Subject matter wherein upon the failure of a primary power supply there is energized a secondary power supply to maintain operation of the electrical means providing the humanly perceptible signal.

SEE OR SEARCH CLASS:
307, Electrical Transmission or Interconnection Systems, 64 for substitute or emergency source in a generic plural power supply transmission system.

Having reduced power consumption (e.g. intermittent power):
This subclass is indented under subclass 693.1. Subject matter wherein means causing the power supply to operate at less than full strength for at least part of the time the power supply is in operation are particularly described.

Having specified voltage regulator:
This subclass is indented under subclass 693.1. Subject matter wherein means causing the energy output by the power supply to be at a constant level or in a consistent pattern are particularly described.

Specified housing:
This subclass is indented under subclass 500. Subject matter wherein some portion of the structure of a housing for the electrical means providing the humanly perceptible signal is particularly described.

SEE OR SEARCH CLASS:
248, Supports, subclass 542 for support with indicator or inspection means.
361, Electricity: Electrical Systems and Devices, 679 for electronic systems or devices housing or mounting assemblies.

Configured to promote sensing capability (e.g., smoke detector):
This subclass is indented under subclass 693.5. Subject matter wherein at least a portion of the housing is particularly described in such a way that a sensor inside the housing may detect a condition outside the housing.
(1) Note. For example, the housing structure includes an element to permit air flow or radiation from outside the housing to come into contact with the sensor inside the housing.

Inserted battery required for housing closure:
This subclass is indented under subclass 693.6. Subject matter wherein the housing has structure preventing two or more housing portions from being properly fastened together unless the DC power supply for the electrical means providing the humanly perceptible signal is positioned in its proper place within the housing.

Simulation:
This subclass is indented under subclass 693.5. Subject matter wherein at least a portion of the housing is in the shape of a further object unrelated to the alarm condition but clearly recognizable to a person or persons to whom the humanly perceptible signal is directed.

SEE OR SEARCH THIS CLASS, SUBCLASS:
691.2 for simulated effect indicator.

Having specified mounting structure:
This subclass is indented under subclass 693.5. Subject matter wherein means for attaching the sensor housing to a further structure, which may or may not be the object or portion of the object sensed by the sensor, are particularly described.

To wall or ceiling:
This subclass is indented under subclass 693.9. Subject matter wherein the further structure is a wall or ceiling.

Within another housing:
This subclass is indented under subclass 693.9. Subject matter wherein the further structure is the object having a condition sensed by the sensor, the object itself having an outer housing, and the sensor housing is secured within the outer housing of the object.

VISUAL INDICATION:
This subclass is indented under the class definition. Subject matter comprising a means for producing a visually
perceptible indication of the presence, absence, or occurrence of an electrical signal.
(1) Note. Indicators for quantitative characteristic of the electrical signal (e.g., voltage) per se, are excluded from this subclass and are classified in Class 324.
(2) Note. The presence, absence, or occurrence of the electrical signal and the resulting visual indication is often intended to indicate some other condition or state or to convey some message (e.g., servant "call" annunciators).
(3) Note. Display of printed or painted objects that does not contain electrical communication is classified in Class 40 Card, Picture, or Sign Exhibiting.
(4) Note. Mechanical, as distinguished from electrical, devices for giving signals of the nature of either alarms or indicators are classified in Class 116, Signals and Indicators.
(5) Note. Radiant energy actuated visual indicators, (i.e., all methods and apparatus for using, generating, controlling, or detecting radiant energy) that do not contain electrical communications are found in Class 250, Radiant Energy.
(6) Note. An optical element or an optical element system that includes a liquid crystal display is classified in Class 349, Liquid Crystal Cells, Elements and Systems, appropriate subclasses for utilizing a liquid crystal device in general.
(7) Note. A light source structure to cast light in at least one direction to render objects in that direction visible and/or the combination of a source of visible radiant energy and means to modify the distribution or composition of the radiant energy emanating from the source, or methods for utilizing said combination are found in Class 362, Illumination.
(8) Note. Display systems having selective electrical control are classified in Class 345, Computer Graphics Processing, Operator Interface Processing, and Selective Visual Display Systems.

SEE OR SEARCH THIS CLASS, SUBCLASS:
286.01 for a signalling system having a visual indicator.
435 for visual indicators used with vehicles.
500 for a condition responsive indicating system, particularly subclass 600 for condition responsive radiant energy used in electrical communication.
907 for visual indicators used to control vehicle or pedestrian traffic.

SEE OR SEARCH CLASS:
40, Card, Picture, or Sign Exhibiting, appropriate subclasses for indicators void of electrical communications.
116, Signals and Indicators, subclass 200 for mechanical indicators.
219, Electric Heating, subclass 248 for a heating device combined with a sole plate-type pressure application means (e.g., a flatiron, etc.) including a condition-responsive indicator or subclass 720 where a control system for a microwave heating device has a display or alarm.
250, Radiant Energy, appropriate subclasses for radiant energy responsive signalling.
313, Electric Lamp and Discharge Devices, subclass 513 for character display with particular mask or electrode shape.
315, Electric Lamp and Discharge Devices: Systems, subclass 169.1 for a visual indicator used in the shifting of a register, counter, or display.
345, Computer Graphics Processing, Operator Interface Processing, and Selective Visual Display Systems, 1 for selective electrical control display systems.
349, Liquid Crystal Cells, Elements and Systems, appropriate subclasses for utilizing a liquid crystal device in general.
359, Optics: Systems (Including Communication) and Elements, 265 for a nonselective electrochronic display element.
362, Illumination, appropriate subclasses for electric lights and associated apparatus used for illumination.
368, Horology: Time Measuring Systems or Devices, 223 for displays or display devices details.
482, Exercise Devices, subclass 3 for pace setting indicator and subclass 84 for striking exercise devices having indicators.
902, Electronic Funds Transfer, subclass 21 for ATM (Automatic Teller Machine) with specific data output means or indicator.

False signal prevention (anti-sunlight):
This subclass is indented under subclass 815.4. Subject matter having means for preventing an improper indication.

Having light piping:
This subclass is indented under subclass 815.4. Subject matter including a light conducting material characterized by an extended longitudinal dimension along which it guides light from a light admitting end connected to a light source to a light emitting end configured to display the visually perceptible indication.

SEE OR SEARCH CLASS:
40, Card, Picture, or Sign Exhibiting, subclass 547 for fiber optic illuminated sign.
250, Radiant Energy, appropriate subclasses for light piping used in radiant energy.
362, Illumination, subclass 26 for edge illuminated modifier or light rod/pipe.
385, Optical Waveguides, appropriate subclasses for fiber optics, particularly 116 for fiber optical imaging including shaping, enhancing, and correcting coherent fiber structure, per se.

With specified colors:
This subclass is indented under subclass 815.42. Subject matter having means for selecting the displayed colors of the visually perceptible indication.
(1) Note. Means for selecting the displayed colors comprises, for example, color filter, color wheel, or a plurality of light sources.

SEE OR SEARCH CLASS:
345, Computer Graphics Processing, Operator Interface Processing, and Selective Visual Display Systems, 150 for selectable color attributes display systems having selective electrical control.

Seven-segment indicator:
This subclass is indented under subclass 815.4. Subject
matter in which the visually perceptible indication consists of segments of a seven-segment character.

SEE OR SEARCH CLASS:
40, Card, Picture, or Sign Exhibiting, subclass 450 for bar segment (e.g., figure eight).
313, Electric Lamp and Discharge Devices, subclass 510 for luminescent solid or liquid material with character display (e.g., digits or letters) and subclass 581 for three or more electrode discharge devices.
315, Electric Lamp and Discharge Devices: Systems, 129 for signal, indicator, or alarm.
345, Computer Graphics Processing, Operator Interface Processing, and Selective Visual Display Systems, subclass 34 for seven-segment display in selective display systems.

Using light emitting diodes:
This subclass is indented under subclass 815.4. Subject matter in which the signal indicating device is a light emitting semiconductor device.

SEE OR SEARCH CLASS:
250, Radiant Energy, subclass 214 for light amplifiers and subclasses 552+ for solid state light source, including matrices and array, per se.
257, Active Solid-StateDevices (e.g., Transistors, Solid-State Diodes), subclass 13, 79 through 103, and 918 for incoherent light emitting injection luminescent devices.
345, Computer Graphics Processing, Operator Interface Processing, and Selective Visual Display Systems, subclass 39, 47, and 82+ for light emitting diode display in selective display systems.

Audio responsive lamp:
This subclass is indented under subclass 815.4. Subject matter comprising an electric light controlled or powered by electrical signals representative of sound waves.

SEE OR SEARCH CLASS:
367, Communications, Electrical: Acoustic Wave Systems and Devices, 197 for acoustic responsive selective system in general.

Switchboard or panel type (e.g., bullseye):
This subclass is indented under subclass 815.4. Subject matter comprising electric light means associated with a plurality of circuit breakers to indicate the status (opened or closed) of the circuit breakers.

SEE OR SEARCH CLASS:
379, Telephonic Communications, 308 for switching apparatus, per se.

Pushbutton:
This subclass is indented under subclass 815.47. Subject matter in which a manual actuator must be depressed to operate the circuit breakers.

Housing:
This subclass is indented under subclass 815.47. Subject matter wherein the indicating means is enclosed in a protective covering.

SEE OR SEARCH THIS CLASS, SUBCLASS:
815.73 for lamp enclosed in transparent housing.

Including optical means:
This subclass is indented under subclass 815.49. Subject matter comprising a lens covering part of the signal indicating device for affecting the light emitted therefrom.

Including spring:
This subclass is indented under subclass 815.49. Subject matter comprising a resilient member.
(1) Note. This subclass includes, for example, a resilient member for controlling the energization of the indicating means, or for holding, supporting, or retaining the indicating means in its position.

With details of energizing circuit:
This subclass is indented under subclass 815.47. Subject matter comprising at least an electrical component for controlling the energization of the indicating device.
(1) Note. The component includes, for example, a resistor, transistor, contact, or circuit breaker.

Lighted alphanumeric or character indicator matrix:
This subclass is indented under subclass 815.4. Subject matter comprising means for illuminating or emitting light to form alphanumeric or character indicative elements arranged in rows and/or columns.
(1) Note. Means for illuminating includes, for example, an ambient and/or an artificial light source.

SEE OR SEARCH CLASS:
40, Card, Picture, or Sign Exhibiting, 447 for alphanumeric devices and subclasses 541+ for illuminated sign.
313, Electric Lamp and Discharge Devices, subclass 510 for luminescent solid or liquid material with character display (e.g., digits or letter).
345, Computer Graphics Processing, Operator Interface Processing, and Selective Visual Display Systems, 25 for cathode-ray tube with alphanumeric display and subclasses 141+ for character display in a generic selective display system.
362, Illumination, 23 for illuminated scale or dial.

Having optical means in viewing path:
This subclass is indented under subclass 815.53. Subject matter having a light modifying means between the light source and the matrix for affecting the presentation of the indicative elements.
(1) Note. The optical means includes, for example, a lens, mask, grating, mirror, light guides, etc.

SEE OR SEARCH CLASS:
345, Computer Graphics Processing, Operator Interface Processing, and Selective Visual Display Systems, subclass 32 for optical means interposed in viewing path (e.g., filters, lens) in a generic selective display system.
359, Optics: Systems (Including Communication) and Elements, 602 for glare or unwanted light reduction with mirror, subclasses 515+ for signal reflector, and subclasses 642+ for lens, per se.

Transparent or translucent indicator with means for blocking light:
This subclass is indented under subclass 815.4. Subject matter wherein the perceptible indication is formed by a light source, a transparent or a translucent panel, and a screen or mask to permit selected parts of the light to pass therethrough.

SEE OR SEARCH CLASS:
40, Card, Picture, or Sign Exhibiting, 541 for illuminated sign.
359, Optics: Systems (Including Communication) and Elements, subclass 608 for translucent or semi-transmitting panel positioned in front of an adjustable anti-glare mirror.

Color:
This subclass is indented under subclass 815.55. Subject matter including means to display the perceptible indication in selected color.

Having optical device:
This subclass is indented under subclass 815.55. Subject matter comprising a lens or a lens system for directing the rays of light from the light source to affect the formation of the perceptible indication.

SEE OR SEARCH CLASS:
345, Computer Graphics Processing, Operator Interface Processing, and Selective Visual Display Systems, subclass 32 for optical means interposed in viewing path (e.g., filters, lens) in a generic selective display system.
359, Optics: Systems (Including Communication) and Elements, 515 for signal reflector and subclasses 642+ for lens.

Step by step positioner:
This subclass is indented under subclass 815.4. Subject matter comprising pawl means engaging a toothed member for intermittently moving it by a distance of one or a series of teeth at a time to present the visually perceptible indication.

SEE OR SEARCH CLASS:
235, Registers, subclass 144 for pawl and notch.
345, Computer Graphics Processing, Operator Interface Processing, and Selective Visual Display Systems, 108 for plural mechanically movable display elements with selective electrical control in selective display systems.

Having resetting device:
This subclass is indented under subclass 815.58. Subject matter comprising means for restoring the positioner or the visually perceptible indication to normal position.

Remote controller:
This subclass is indented under subclass 815.58. Subject matter wherein the operation of a distant step by step positioner is controlled over a wire or wireless communication channel by circuitry at a transmitting station.

Drum indicator:
This subclass is indented under subclass 815.58. Subject matter wherein the intermittently moved toothed member causes a rotation of a cylindrical mechanical element bearing alphanumeric or character indicative elements on its periphery thereby presenting the visually perceptible indication.

SEE OR SEARCH THIS CLASS, SUBCLASS:
815.64 for indicator wheel operated by electromagnetic rotator.

Electromagnetic actuator for indicator matrix:
This subclass is indented under subclass 815.4. Subject matter comprising an electromagnet capable of producing a force to change the positions of indicative elements arranged in an array thereby presenting the perceptible indication.

Binary indicator:
This subclass is indented under subclass 815.4. Subject matter in which the signal indicating device moves between first and second limit positions to indicate either one of two predetermined states in an operational system.
(1) Note. The two predetermined states may be, for example, set and reset, on and off, normal or fault, etc.

Electromagnetic rotator for indicator wheel:
This subclass is indented under subclass 815.4. Subject matter comprising an electromagnet capable of producing a
force to rotate a wheel having indicative elements arranged on its face or around its periphery thereby presenting the perceptible indication.

SEE OR SEARCH THIS CLASS, SUBCLASS:
815.61 for drum indicator that rotates intermittently by a distance of one or a series of teeth at a time.

Multiple colors:
This subclass is indented under subclass 815.4. Subject matter which produces the visually perceptible indication in at least two different colors.

SEE OR SEARCH CLASS:
345, Computer Graphics Processing, Operator Interface Processing, and Selective Visual Display Systems, 150 for selectable color attributes display systems having selective electrical control.

By light signal:
This subclass is indented under subclass 815.65. Subject matter in which the indication is produced by light rays emitted from a light source.

SEE OR SEARCH CLASS:
40, Card, Picture, or Sign Exhibiting, subclass 581 for a colored light illuminated sign and subclass 444 for selective or intermittent illumination with colored light.

Plural:
This subclass is indented under subclass 815.66. Subject matter having a plurality of light sources.

With movable optical means:
This subclass is indented under subclass 815.66. Subject matter comprising means for selectively moving a light modifier located between the light source and the indication to produce different colors.
(1) Note. The optical means comprises, for example, a color filter, lens, colored shutter, or screen.

Diverse indications:
This subclass is indented under subclass 815.4. Subject matter for giving different types of indications.

SEE OR SEARCH CLASS:
116, Signals and Indicators, 2 for nonelectrical combined function and subclass 280 for nonelectrical diverse indicators.

Having percussion type indication (e.g., electric bells, chimes):
This subclass is indented under subclass 815.69. Subject matter in which one of the indications is an audible sound produced by means having a striking mechanism.

SEE OR SEARCH THIS CLASS, SUBCLASS:
392.1 for percussion type sound producer (e.g., signal chimes or bells).

SEE OR SEARCH CLASS:
84, Music, subclass 404 for rigid vibrating instrument with striker and subclass 407 for bells with electric action.
379, Telephonic Communications, subclass 376 for signal reception at substation with visual indication of incoming call.

Electromagnetic:
This subclass is indented under subclass 815.7. Subject matter comprising an electromagnet for operating the striking mechanism.

Having pneumatic type indication:
This subclass is indented under subclass 815.69. Subject matter in which one of the indications is an audible sound produced by the flow of air or other gaseous substances.

SEE OR SEARCH THIS CLASS, SUBCLASS:
404.1 for pneumatic type sound producer (e.g., whistle or siren).

With lamp enclosed in transparent housing:
This subclass is indented under subclass 815.4. Subject matter having an electric lamp or discharge device inside a light transmissive enclosure.

SEE OR SEARCH THIS CLASS, SUBCLASS:
815.49 for housing of switch board or panel type indicator.

SEE OR SEARCH CLASS:
362, Illumination, subclass 362 for lamp enclosed in housing.

Combined:
This subclass is indented under subclass 815.73. Subject matter combined with diverse art subject matter.

Light source modifier:
This subclass is indented under subclass 815.73. Subject matter having means to control the duration or intensity or direction of the light emanating from the lamp.

SEE OR SEARCH CLASS:
345, Computer Graphics Processing, Operator Interface
Processing, and Selective Visual Display Systems, subclass 147 for intensity control in generic selective electrical display systems.

Lens type:
This subclass is indented under subclass 815.75. Subject matter in which the transmissive enclosure comprising an optical device for focussing, converging, or diverging the light emitted from the lamp or the discharge device to obtain a desired light emitting characteristic.

SEE OR SEARCH THIS CLASS, SUBCLASS:
22 for signal lens used as traffic lenses or vehicle indication.

SEE OR SEARCH CLASS:
359, Optics: Systems (Including Communication) and Elements, 642 for lenses, per se.

Relatively movable light source:
This subclass is indented under subclass 815.73. Subject matter having means for moving the lamp within the enclosure.

Pointer indicator:
This subclass is indented under subclass 815.4. Subject matter comprising a movable needle positioned to indicate the visually perceptible indication.

SEE OR SEARCH THIS CLASS, SUBCLASS:
815.86 for rotary indicator.

SEE OR SEARCH CLASS:
116, Signals and Indicators, 284 for nonelectrical rotary indicator having pointers.

Annunciator:
This subclass is indented under subclass 815.78. Subject matter wherein the needle is raised or dropped from an inoperative position to an operative position to indicate the visually perceptible indication.

Having electromagnetically releasable latch:
This subclass is indented under subclass 815.79. Subject matter in which the needle is released for movement by the operation of an electromagnetically releasable latch.

SEE OR SEARCH THIS CLASS, SUBCLASS:
815.9 for indicator having electromagnetically releasable latch.

Grouped drop annunciators:
This subclass is indented under subclass 815.4. Subject matter having a multi unit indicator comprising a device operable to move a plurality of visually perceptible members (i.e., targets) individually or simultaneously from a nonsignalling position to a signalling position.

Support:
This subclass is indented under subclass 815.81. Subject matter comprising a framework for mounting the drops or targets.

Movable:
This subclass is indented under subclass 815.4. Subject matter wherein the indicating device (i.e., target) signals by a change of position.

SEE OR SEARCH CLASS:
345, Computer Graphics Processing, Operator Interface Processing, and Selective Visual Display Systems, 108 for plural mechanically movable display elements with selective electrical control in selective display systems.

Semaphore:
This subclass is indented under subclass 815.83. Subject matter wherein the signalling indicating device comprises one or more movable arms positioned to produce the visually perceptible indication.

SEE OR SEARCH THIS CLASS, SUBCLASS:
127 for semaphore used in traffic and vehicle signalling.

SEE OR SEARCH CLASS:
116, Signals and Indicators, subclass 319 for an arm that is a rotary indicator.

Self restoring type annunciator:
This subclass is indented under subclass 815.83. Subject matter comprising a target raised into an operative position by an energized electromagnet and dropped back to an inoperative position by gravitational force.

Rotary:
This subclass is indented under subclass 815.83. Subject matter wherein the visual indicator moves with a rotary motion.

SEE OR SEARCH THIS CLASS, SUBCLASS:
815.58 for step by step positioner.
815.63 for indicator that rotates between two positions to indicate either one of two predetermined operational states.
815.64 for indicator wheel operated by an electromagnetic rotator.
815.78 for pointer indicator.

SEE OR SEARCH CLASS:
116, Signals and Indicators, subclass 284 for nonelectrical rotary indicator with actuating means.
345, Computer Graphics Processing, Operator Interface Processing, and Selective Visual Display Systems, subclass 126 for rotation of images on a generic selective display system.

Rotor driven:
This subclass is indented under subclass 815.86. Subject matter in which the rotary motion is generated by an electromagnetic rotor mounted on a shaft.

Vane indicator:
This subclass is indented under subclass 815.86. Subject matter comprising a hinged indicator swinging between positions to produce the visually perceptible indication.

Circuit closing type:
This subclass is indented under subclass 815.83. Subject matter having means to close a switching or a contacting device of a normally open circuit when the signalling device moves.

By electromagnetically releasable latch:
This subclass is indented under subclass 815.83. Subject matter wherein the target is released for movement by the operation of an electromagnetically releasable latch.

SEE OR SEARCH THIS CLASS, SUBCLASS:
815.8 for pointer annunciator having an electromagnetically releasable latch.

Having restoring means:
This subclass is indented under subclass 815.9. Subject matter comprising means for resetting the released target to a normal position.

Gravity operated drop annunciator:
This subclass is indented under subclass 815.9. Subject matter in which the target is moved into an annunciation or a set position by gravitational force.

SELECTIVE:
This subclass is indented under the class definition. Subject matter for controlling one or more devices to obtain a plurality of results by transmission of a designated one of plural distinctive control signals over a smaller number of communication lines or channels than the total number of possible distinct results.
(1) Note. As used hereinafter, the term transmitter refers to the source of signals, and the term receiver refers to circuitry responsive to such signals.
(2) Note. This subject matter differs from simple switching in providing more than one result per channel in accordance with the signal content, as, for example, addressing one of a plurality of devices over a single channel.
(3) Note. Systems containing receivers, receivers and receiver subsystems, are classified in this and indented subclasses.
(4) Note. Transmission of signals providing for messages of arbitrary content is not classified herein.
(5) Note. Combinations with a specific art end element are usually classified therewith.

SEE OR SEARCH THIS CLASS, SUBCLASS:
286.01 for manually actuated alarm systems.
438 for alarms or indicators associated with the selective control devices of a vehicle, especially subclass 456 for transmission gear selectors, subclasses 457+ for "reminder" indicators of various selectable functions, and subclasses 475+ for turn signals.
500 for condition responsive indication.
517 for selective indication of one of a plurality of sensed conditions.
853.3 for selective control in a wellbore communications system.
870.01 for telemetry which may be combined with or have selectivity.

SEE OR SEARCH CLASS:
29, Metal Working, appropriate subclasses for miscellaneous manufacturing processes.
60, Power Plants, subclasses 700-710 and 719 for control of power plants.
82, Turning, subclass 48 for triggered severing or cutoff control.
114, Ships, 365 for life craft handling.
118, Coating Apparatus, subclass 695 and 696 for selective control of coating apparatus.
177, Weighing Scales, subclass 14 for selectively preset cycle flow terminators.
178, Telegraphy, 33 for telegraph selectors.
180, Motor Vehicles, 6.2, 167+, and 204 for selective control of motor vehicles.
200, Electricity: Circuit Makers and Breakers, 1 for multiple circuit control.
219, Electric Heating, subclass 714 for a remote control system for a microwave heating device.
222, Dispensing, subclass 639 for electrical control of dispensing.
234, Selective Cutting (e.g., Punching), appropriate subclasses.
235, Registers, 375 for selective control by means of data-bearing records.
244, Aeronautics, 3.1 for missile trajector control; and
subclasses 175+ for electric aircraft control.
246, Railway Switches and Signals, appropriate subclasses for selective systems in railway signalling.
273, Amusement Devices, 237 for electrical board games.
290, Prime-Mover Dynamo Plants, 7 for electric control of prime-mover dynamo plants.
307, Electrical Transmission or Interconnection Systems, subclass 29, 37, and 38+ for control of individual loads in an electric power distribution system; subclass 115 for a power-switching system having selective actuation; and subclasses 401+ for magnetic reactor systems.
318, Electricity: Motive Power Systems, 34 for diverse plural controlled electric motors.
322, Electricity: Single Generator Systems, appropriate subclasses for control of electrical generating systems.
327, Miscellaneous Active Electrical Nonlinear Devices, Circuits, and Systems, 518 for miscellaneous control circuits and subclasses 365+ for miscellaneous gating circuits.
334, Tuners, 8 for remotely controlled tuners.
335, Electricity: Magnetically Operated Switches, Magnets, and Electromagnets, 107 and 138+ for a selectively controlled switch.
337, Electricity: Electrothermally or Thermally Actuated Switches, subclass 10 and 44 for a selectively controlled switch.
341, Coded Data Generation or Conversion, subclasses 173-192 for coded generator or transmitter.
342, Communications: Directive Radio Wave Systems and Devices (e.g., Radar, Radio Navigation), appropriate subclass for selective communications in the directive radio wave systems.
345, Computer Graphics Processing, Operator Interface Processing, and Selective Visual Display Systems, 1 for plural display communication systems.
359, Optics: Systems (Including Communication) and Elements, 142 for optical remote control.
361, Electricity: Electrical Systems and Devices, 139 and 211 for selective control relays; and subclass 160 for relay control systems.
365, Static Information Storage and Retrieval, appropriate
subclasses for static memory devices which may be selectively operated, or which may be in the form of a matrix.
367, Communication, Electrical: Acoustic Wave Systems and Devices, appropriate subclasses for selective systems having an acoustic communications link.
369, Dynamic Information Storage and Retrieval, 24 for selective remote control; especially subclasses 30+ for selective addressing of storage medium or portion thereof (e.g., programmed access, "jukebox").
370, Multiplex Communications, appropriate subclasses for multiplex communications in general.
375, Pulse or Digital Communications, appropriate subclasses for pulse communications in general.
377, Pulse Counters, Pulse Dividers, or Shift Registers: Circuits and Systems, appropriate subclasses for electrically operated registers which may have selective operation.
395, Information Processing System Organization, 200.3 for data transferring among multiple computer systems.
455, Telecommunications, appropriate subclasses for analog communications in general.
477, Interrelated Power Delivery Controls, Including Engine Control, for interrelated control between a motor and a transmission, clutch, or brake.
704, Data Processing: Speech Signal Processing, Linguistics, Language Translation, and Audio Compression/Decompression, 200 for special signal processing.
710, Electrical Computers and Digital Data Processing Systems: Input/Output, 1 for transferring data from one or more peripherals to one or more computers for the latter to process, store, or further transfer or for transferring data from the computers to the peripherals (i.e., input/output processing); subclass 100 for system intraconnecting for access regulating and arbitration within a digital data processing system; subclasses 107+ for bus access regulating; subclasses 200 through 244 for generalized locking, polling, access arbitrating; and subclasses 260 through 269 for interrupt processing.
711, Electrical Computers and Digital Processing Systems: Memory, 200 for generalized address forming.

Spare channel:
This subclass is indented under subclass 825. Subject matter having one or more communication channels additional to those in normal use, which additional channels are used solely in the event of a fault in, or failure of, a normally used communication channel.

SEE OR SEARCH CLASS:
714, Error Detection/Correction and Fault Detection/Recovery, 3 for replacement with a spare in response to a fault, and subclass 821 for plural parallel communication channels.

Tree or cascade:
This subclass is indented under subclass 825. Subject matter having alternatively operable circuitry branches which are selectively operable, each of said branches further exercising selective control upon succeeding circuitry, and there being no connection between the separate branch circuits.

Channel selection:
This subclass is indented under subclass 825. Subject matter having a plurality of alternative communication lines and selection of less than the total number of lines for signal transmission.
(1) Note. Alternative communication lines include input or output channels.

SEE OR SEARCH CLASS:
710, Electrical Computers and Digital Data Processing Systems: Input/Output, 100 for system intraconnecting, and subclasses 131 through 132 for path selection and switching (e.g., crossbar switching) in a digital data processing system.

Code or pulse responsive:
This subclass is indented under subclass 825.03. Subject matter wherein the channel selection is performed in response to a specified pulse or pulse pattern.

SEE OR SEARCH THIS CLASS, SUBCLASS:
825.57 for pulse-responsive selective systems, in general.

Monitoring and control (e.g., supervisory):
This subclass is indented under subclass 825. Subject matter wherein a signal representative of the actual status of the controlled device, with respect to an intended controlled function, is transmitted back to the selective signal source.
(1) Note. The representative signal is generally used for an indication or control function at the selective signal source.

With addressing:
This subclass is indented under subclass 825.06. Subject matter with a plurality of controlled devices, each of which is responsive to a unique signal so as to permit individual control.

SEE OR SEARCH THIS CLASS, SUBCLASS:
825.52 for addressing absent a representative signal.

SEE OR SEARCH CLASS:
711, Electrical Computers and Digital Processing Systems: Memory, 200 for generalized address forming in a digital data processing system.

Polling or roll call:
This subclass is indented under subclass 825.07. Subject matter wherein all of the controlled devices are caused to transmit a representative signal in response to a particular signal.
(1) Note. The transmission of the representative signals may be done in succession.

SEE OR SEARCH CLASS:
710, Electrical Computers and Digital Data Processing Systems: Input/Output, subclasses 113-118 for centralized bus arbitration, subclasses 119-125 for decentralized bus arbitration, and subclass 220 for generalized access polling in a digital data processing system.

Quiescent:
This subclass is indented under subclass 825.06. Subject matter wherein the representative signal is transmitted solely in response to a change in condition.

Scanning:
This subclass is indented under subclass 825.06. Subject matter having plural controlled devices with successive transmission of representative signals from each of the controlled devices.

Continuous:
This subclass is indented under subclass 825.10. Subject matter wherein the scanning is automatically restarted at its conclusion.

Interrupted:
This subclass is indented under subclass 825.10. Subject matter having structure to interrupt the normal scanning sequence.
(1) Note. Such interruption may be for the purpose of obtaining an indication of a particular controlled device.

Automatic:
This subclass is indented under subclass 825.12. Subject
matter wherein the interruption is in response to a predetermined representative signal.

Synchronization:
This subclass is indented under subclass 825.06. Subject matter including a reference timing function for operating plural system components.
(1) Note. The reference timing function often includes a clock-pulse generator.

SEE OR SEARCH THIS CLASS, SUBCLASS:
825.2 for such subject matter absent monitoring and control.

With storage or recording:
This subclass is indented under subclass 825.06. Subject matter combined with the production of a permanent or semipermanent record of a control or representative signal.
(1) Note. The term "record" is not limited to a tangible object, but includes a stored pattern in a static storage device (e.g., magnetic core matrix).

Fault condition:
This subclass is indented under subclass 825.06. Subject matter which produces a representative signal in response to a malfunction of the selective device.
(1) Note. The term "malfunction" is intended to include disagreement between intended and actual controlled function.

With indicator:
This subclass is indented under subclass 825.06. Subject matter having an element which produces a humanly perceptible
signal.

Relay:
This subclass is indented under subclass 825.06. Subject matter having an electromagnetic relay.

SEE OR SEARCH CLASS:
361, Electricity: Electrical Systems and Devices, 160 for a relay control system.

Communication or control for the handicapped:
This subclass is indented under subclass 825. Subject matter which performs a function normally performed directly by an individual and particularly adapted for control by physically impaired individual.

SEE OR SEARCH CLASS:
704, Data Processing: Speech Signal Processing, Linguistics, Language Translation, and Audio Compression/Decompression, 258 for a speech synthesizer using sequential sounds.

Synchronizing:
This subclass is indented under subclass 825. Subject matter including a reference timing function with respect to which different control functions are performed.

With addressing:
This subclass is indented under subclass 825.2. Subject matter having plural controlled devices, each one of which is actuated by a signal having a unique characteristic corresponding to the respective one of the controlled devices.
(1) Note. The term "unique characteristics" refers to a parameter, the content, or the relative time of occurrence of
the signal.

Program control:
This subclass is indented under subclass 825. Subject matter producing each of a plurality of different results in a time sequential manner.
(1) Note. The term "time sequential manner" is intended to denote control of the order in which the different results are performed.

Machine tool:
This subclass is indented under subclass 825.22. Subject matter for control of a work-contacting element which causes a physical alteration in the work (e.g., chipping, boring).

SEE OR SEARCH THIS CLASS, SUBCLASS:
825 for search notes to machine tools.

Of audio systems:
This subclass is indented under subclass 825.22. Subject matter in which the results are intended to control various aspects of an audible signal producing system.
(1) Note. Included herein are selection of distinct audio messages.

SEE OR SEARCH THIS CLASS, SUBCLASS:
825.25 for nonprogram audio system control.

Audio system (e.g., by pulse signal):
This subclass is indented under subclass 825. Subject matter wherein the controlled device is a nominally recited, audible signal reproducing system.
(1) Note. A selectively controlled audio system with details thereof is classified with such an audio system.

SEE OR SEARCH THIS CLASS, SUBCLASS:
825.24 for such subject matter with program control thereof.

SEE OR SEARCH CLASS:
360, Dynamic Magnetic Information Storage or Retrieval, 77.01 for selection of a track on a magnetic record carrier.
369, Dynamic Information Storage or Retrieval, subclass 33 for phonographs having selective control circuitry.
455, Telecommunications, 31.1, 88, 92, 151.1, or 352+, as appropriate, for remote control of a modulated wave communication system or subsystem.

Stock quotation:
This subclass is indented under subclass 825. Subject matter wherein the controlled device is particularly designed for display of stock prices and is geos:graphically separated from the information source of such prices.
(1) Note. The device may include control circuitry for inquiring about a designated stock.

With information storage:
This subclass is indented under subclass 825.26. Subject matter having an arrangement to store the stock price information.
(1) Note. Detailed structure of the storage arrangement is classified in an appropriate information storage class.

Space allocation (e.g., vehicle seat, hotel reservation):
This subclass is indented under subclass 825. Subject matter including a display for indicating the availability of spaces which may be reserved, and a control for modifying such availability by making or cancelling reservations for the
spaces.

SEE OR SEARCH CLASS:
705, Data Processing: Financial, Business Practice, Management, or Cost/Price Determination, subclass 5 for subject matter combined with a data processing feature.

Remote terminal:
This subclass is indented under subclass 825.28. Subject matter having an information storage device in which the space availability is stored at a geos:graphically spaced location from the display and control.

Intelligence comparison:
This subclass is indented under subclass 825. Subject matter which compares an information bearing item or signal with an information reference, and performing a control function in accordance with the comparison.
(1) Note. Control by a data bearing record (e.g., credit card) is classified elsewhere. See search note below.

SEE OR SEARCH CLASS:
235, Registers, 375 for systems controlled by data bearing records; subclasses 435+ for coded record sensors; and subclasses 487+ for data bearing records, per se.

Authorization control (e.g., entry into an area):
This subclass is indented under subclass 825.30. Subject matter wherein the comparison determines the operation of a controlled device to permit an individual to perform some action.

SEE OR SEARCH CLASS:
235, Registers, subclass 382 for similar subject matter where entry is controlled by a data bearing record.

With alarm or indication of improper access:
This subclass is indented under subclass 825.31. Subject matter which additionally produces a humanly perceptible signal indicative of an access attempt by other than the correct signal.
(1) Note. Included herein are alarms for unsuccessful comparison and tamper indication.

SEE OR SEARCH THIS CLASS, SUBCLASS:
541 for an intrusion responsive indicator or alarm.