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 in