This class provides for apparatus used in separation of a gas from a fluid mixture comprising (i) a gas and solid or liquid particles entrained therein, (ii) a liquid and gas entrained therein, or (iii) a plurality of gases. As a general rule for this class, there must be a relationship of apparatus parts embracing: (a) an inlet for the fluid mixture to be treated, (b) a means effective to cause separation into constituent parts, and (c) an outlet for at least one constituent separate and distinct from an outlet for another constituent, which may be for removal of the separating media itself, or a single outlet used at different times to remove the separated
constituents. The gas separation apparatus for this class does not include means in which the separation is caused by a chemical reaction.
The basic subject matter of this class is of a subcombination nature and may include only such ancillary apparatus (e.g., fluid handling means, etc.) as is necessary to perfect the gas separating function. Significant inclusion in a claim of features beyond merely perfecting the gas separating function indicates classification in a more comprehensive class. Generally, however, the mere naming of an art device in a claim to a gas separator does not affect classification. Thus, a claim to an air filter combined with a nominally included motor vehicle is proper for this class.
(1) Note. The gas separation apparatus for this class generally involves means to use a magnetic field, to use an electrical field, to diffuse selectively, to sorb on a solid sorbent, to degasify a liquid, to contact a gas with a liquid, to filter, or to deflect, or involves other mechanical means. See Lines With Other Classes, below, for the line concerning the means in which the gas separation is caused by a chemical reaction.
(2) Note. This class also provides for the subcombination of the separating media, per se, when disclosed for gas separating. However, see Lines with other Classes, and References to Other Classes, below, for solid sorbents and liquid sorbents.
(3) Note. Devices which may inherently perform a gas separating function but are not found in this class include grids, gratings, grilles, woven fabrics, screens, and the like. They will be found in a stock material class, for which see Lines With Other Classes, Below. However, devices of these types when positively stated as being for gas separation will be found in Class 96.
(4) Note. This class also provides for apparatus in which the fluid mixture is treated to change its make-up, but no real separation occurs, provided no other suitable classification exists. Accordingly, in this class are found "spark arresters," which merely change the size of particles entrained in a gas. (See References To Other Classes for the line concerning spark arresters when used on furnaces.) These devices are usually deflectors or screens and are included in this class because of their similarity to apparatus which actually separate the fluid mixture into constituent parts. Similarly, agglomerators which by themselves may not separate constituents of a fluid mixture, but cause small particles therein to join together or coalesce to form larger particles, are in this class unless basis for other classification exists.

LINES WITH OTHER CLASSES AND WITHIN THIS CLASS
See the class search note for Class 422, Chemical Apparatus
and Process Disinfecting, Deodorizing, Preserving, or Sterilizing, for the line concerning the means in which the gas separation is caused by a chemical reaction.
Solid sorbants are found in Class 502, Catalyst, Solid Sorbent, or Support Therefor: Product or Process of Making, and liquid sorbents are found in Class 252, Compositions. (Also see the search class notes below.)
Devices which may inherently perform a gas separating function but are not found in this class include grids, gratings, grilles, woven fabrics, screens, and the like. They will be found in a stock material class (e.g., Class 428, Stock Material or Miscellaneous Articles, etc.).

REFERENCES TO OTHER CLASSES

SEE OR SEARCH CLASS:
15, Brushing, Scrubbing, and General Cleaning, appropriate subclasses for gas separation devices claimed in combination with a work contacting tool (e.g., a vacuum cleaner comprising a device contacting the work to be cleaned and an air filter, etc.) and 301 for gas separating means associated with fixed position or installed cleaners. For classification in Class 15, subclasses 301+, it is not necessary to claim the work contacting tool; it is sufficient to claim a building modification to accommodate the system parts or some special modification of the apparatus for its intended use, such modification going beyond mere ground support means.
34, Drying and Gas or Vapor Contact With Solids, appropriate subclasses for generic apparatus for separating liquids from solids (i.e., drying) and the contacting of solids with either gases or vapors. Class 96 takes the apparatus for the separation of a gas from a fluid mixture in combination with means to regenerate the separating media by drying or by gas or vapor contact.
47, Plant Husbandry, appropriate subclasses for apparatus for separation of a gas from a fluid mixture by use of a plant of higher order.
48, Gas: Heating and Illuminating, appropriate subclasses for apparatus for the manufacture of heating and illuminating gases and means for the purification, distribution, and storage thereof.
60, Power Plants, 272 for a power plant of the internal combustion engine type with treatment or handling of exhaust gas.
62, Refrigeration, appropriate subclasses for apparatus peculiar to removing heat from a substance, usually by a
change of phase of a coolant or refrigerant, and for apparatus involving subject matter for Class 96 combined with significant refrigeration apparatus. Examples of significant refrigeration are: (i) expansion of a gas through an orifice whereby cooling is effected to condense any of the constituents of the gas by such temperature reduction; (ii) a significant physical relationship or arrangement between elements of a refrigeration circuit (e.g., two related refrigeration coils, detailed description of the circuit, etc.); (iii) change of phase of a coolant or refrigerant (i.e., evaporation, melting, or sublimation) whereby cooling is effected to condense any of the constituents of the gas by such temperature reduction. Some examples of what may be found in Class 62 are: (a) separation of a constituent from a plurality of gases by a significantly claimed refrigeration step or apparatus; (b) condensation of moisture from the atmosphere as a result of a refrigeration operation; (c) gas drying by sorption followed by contacting the dried gas with a liquid to produce cooling by evaporation; (d) a refrigerated enclosure combined with sorption means; (e) refrigeration producing processes and apparatus combined with steps or means for drying the refrigerant; and (f) extracting a constituent from a plurality of gases by liquefaction and separation (e.g., fractionation or distillation, etc.).
73, Measuring and Testing, 23.2 for apparatus for gas analysis, per se, and also the combination of gas separation apparatus and significant gas analysis means. The combination of gas separation apparatus and nominal means for "analyzing" or "detecting" without further detail of the analysis or detection means is insufficient to cause a patent to be placed in Class 73; that patent will be placed in Class 96. Also, if there is feedback means from the analytical apparatus to control or effect a change in the gas separation, then classification is in Class 96. For volume or rate of flow meters combined with gas-liquid separators, see Class 73, subclass 200.
95, Gas Separation: Processes, for the corresponding processes to the apparatus of Class 96. When a patent has a claim or claims to a Class 95 process and a claim or claims to a Class 96 apparatus, the patent will be placed as an original in Class 95, even though there may be an apparatus claim that is more comprehensive than a process claim.
110, Furnaces, 119 for significant furnace apparatus including a spark arrester.
118, Coating Apparatus, 715 for coating apparatus in which the coating material used is either gaseous or vaporous. The apparatus may have gas separation means for removing foreign or undesirable components from the coating material.
122, Liquid Heaters and Vaporizers, subclass 492 for devices located in the steam dome of a boiler for separating water from steam.
123, Internal-Combustion Engines, 518 for internal-combustion engines including a charge-forming device having a fuel vapor recovery and storage system.
128, Surgery, 200.24 for apparatus for supplying a breathable gas to, or exhausting such gas from, a living body. Subclass 200.24 and the subclasses mentioned below require that the apparatus be adapted for use on or in the living body and also include diagnostic or therapeutic apparatus when the only disclosed utility is for diagnosis or treatment of a living body. See especially subclass 200.25 for an artificial gill or means for separating entrained air from a liquid stream; subclass 201.25 for a respiratory device including body or head supported means covering user's scalp and means for removing a substance from respiratory gas; subclass 204.16 for removal of a substance from respiratory gas by cooling; subclass 205.12 for means for supplying respiratory gas under positive pressure including means for removing a substance from the respiratory gas; and subclass 205.27 for a respiratory device including means for removing a substance from a respiratory gas.
131, Tobacco, 331 for means for removing or separating a constituent material from tobacco smoke combined with tobacco products or disclosed for use with a tobacco user's appliance or article where the disclosure or claim is directed solely to such use. A copy of a patent so limited as above should be placed as a cross-reference in Class 96 if general utility for gas separation is recognized.
137, Fluid Handling, appropriate subclasses for combinations of fluid handling apparatus and gas separation apparatus involving more than mere flow control (e.g., valving, etc.) to or from the gas separating apparatus. (i) For classification in either Class 137 or Class 96 where both the fluid handling apparatus and gas separation apparatus are included in the combination, classification will be based upon the ultimate purpose of the subject matter and not on the ancillary or subordinate feature of the combination consistent with the objects and aims therefor (e.g., it is not intended that the inclusion of a fabric filter no matter how specifically defined will be sufficient to carry a "gas field storage and distribution system" to Class 96, whether the filter protects the operating parts of the system or is the most downstream element thereof). The fluid handling for Class 96 should be no more than that necessary to convey or conduct the fluid mixture to, at, or away from the point of separation. (ii) However, where (a) the Class 137 feature is a simple valve (e.g., a check valve, a mere stop and go valve, or a mere flow control valve as distinct from a multiway valve or a pressure regulator), (b) the gas separation apparatus and valve are in an intimate flow relationship within a gas conduit, and (c) the gas separation apparatus is claimed by more than name only, classification is in Class 96, regardless of the ultimate purpose of the subject matter and irrespective of the details of the valve recited in the claim. (iii) Class 137 also takes separation
of gases from gases, liquids, or solids by gravitational means only (i.e., where no specific means is claimed for effecting the separation). A single expansion chamber alone which separates a fluid mixture is not regarded as a specific separating means. However, two such chambers (in series or parallel) are considered to be specific. If there is a baffle or other impingement surface claimed, other than the wall of the chamber itself, such apparatus is to be placed in Class 96.
141, Fluent Material Handling, With Receiver or Receiver Coacting Means, appropriate subclasses for apparatus for transferring fluent material through a flow confining system, the source and receiver parts of which are normally separable.
156, Adhesive Bonding and Miscellaneous Chemical Manufacture, appropriate subclasses for apparatus there classified for adhesively bonding and otherwise manufacturing filters.
160, Flexible or Portable Closure, Partition, or Panel, appropriate subclasses for flexible fabric panel units and 382 for fabric fastening means. Class 160 is the generic class for panel units having flexible fabric and takes flexible fabric panel units having several different named purposes, one of which may be gas separation. Class 96 takes a panel unit having flexible fabric when used only for gas separation.
165, Heat Exchange, appropriate subclasses for apparatus where only indirect heat exchange is involved and 58 for a heating and cooling system with an ancillary separator. However, cold wall-hot wall thermal diffusion apparatus will be found in Class 96, subclass 221.
166, Wells, for shafts or deep borings in the earth for the extraction of fluids from the earth. Gas separation apparatus including a nominal recitation of a well is proper for Class 96. For classification in Class 166, some details specific to wells should be recited for the combination of gas separation apparatus and a well. However, in the situation in which one of the constituents separated is inserted into an input well, a mere broad recitation of such well is sufficient for classification in Class 166.
180, Motor Vehicles, subclass 68.3 for modified vehicle structure such as hood modifications and other air inlets (e.g., body grille, etc.) with conduits or connections to or for carburetor intake and including filter means.
181, Acoustics, subclass 231 for a muffler with a solid particle separator (e.g., spark arrester, vacuum cleaner, etc.). See Class 96, subclasses 380+ for gas separation apparatus with sound damping means.
196, Mineral Oils: Apparatus, for apparatus for treating, refining, or recovering mineral oils such as petroleum, coal,
tar, pitch, asphalt, or related products. Class 196 takes apparatus having means for gas separation combined with significant means to treat, refine, or recover mineral oils.
202, Distillation: Apparatus, appropriate subclasses for apparatus for the volatilization of a substance from either solids or liquids for the purpose of recovering material from the vapor produced by condensation or absorption. Other means for the physical treatment of the vapor may be included (e.g., filter, deflector, dephlegmator, etc.).
204, Chemistry: Electrical and Wave Energy, 193 for apparatus in which a chemical change is brought about by the application of an electric current to material being treated wherein more than the mere thermal effect of the current is involved, and subclasses 660+ for apparatus for the separation or purification of liquids by the physical or physical-chemical action of an electrical stress.
209, Classifying, Separating, and Assorting Solids, subclasses indented under subclass 21 and 133 that include "deposition" in their titles for apparatus for the separating and segregating into grades components of solid mixtures employing a gaseous suspending medium which is separated from the solids.
210, Liquid Purification or Separation, appropriate subclasses for apparatus for the separation of a constituent from a flowable liquid mixture; except for apparatus for the separation of a gas initially present in a liquid mixture. Class 210 is superior to Class 96 and takes separating apparatus, per se, generically disclosed or claimed for use in fluid separation or if the disclosure or a claim is restricted to liquid separation apparatus. Class 210 also takes apparatus which removes or vents gas formed incidentally to the handling of the fluid mixture or as a result of a Class 210 treatment (see particularly subclass 120, 180, 188, 218, 406, and 436). However, Class 96 takes apparatus operating to remove gas initially present in an inflowing liquid mixture, with or without liquid separation. Apparatus for the removal of a volatile organic compound (e.g., ethanol (C[subscrpt]2[end subscrpt]H[subscrpt]5[end subscrpt]OH), gasoline, etc.) from a liquid is not taken to be apparatus for the degasification of a liquid for Class 96 when the volatile organic compound is initially present as a liquid mixed with another liquid. Apparatus for the removal of a volatile organic compound from a liquid may be found in Class 210 for liquid purification or separation or Class 202 for separatory distillation. Class 96 will also take apparatus including a liquid separation means in a Class 96 gas separation apparatus (e.g., means to regenerate a scrubbing liquid in a gas scrubbing apparatus, etc.).
215, Bottles and Jars, subclass 308 for closures for bottles and jars with the receptacle interior communicable with the exterior through a filter when the closure is in the applied position.
220, Receptacles, subclass 366 and 367+ for vents for closures for receptacles combined with gas separating means wherein the gas separator is recited by name only, or the claim includes details of the receptacle (e.g., splash plate in the receptacle or vent, etc.) or of the closure (e.g., configuration or means for attaching to the receptacle, etc.).
236, Automatic Temperature and Humidity Regulation, subclasses 53-60 for steam traps with thermostatically controlled valves.
239, Fluid Sprinkling, Spraying, and Diffusing, 34 for slow diffusers, which are devices used to disperse or spread material into the ambient air without the use of draft producing means. With a disclosure of gas separation or humidity control (air conditioning), Class 239 will take, as a slow diffuser, a pad, filter, or fibrous mass that is saturated or maintained saturated with a diffusible liquid (water or volatile solvents) unless any of the following are included: (i) gas contacting means within the meaning of Class 261 (e.g., special flow arrangements through conduits or the like, etc.), or (ii) gas movement effecting means (e.g., pump, fan, etc.). Class 261 will take patents having the qualifications in (i) or (ii) if the filter, pad, or mass is: (a) continuously supplied with liquid, (b) cyclically or periodically moved through a liquid reservoir, (c) maintained wet by liquid applying means, or (d) moistened by maintaining some part of a continuous wick type member immersed in liquid. Class 96 will take patents having the qualifications in (i) or (ii) if the liquid supply means described in (a) through (d) is not included. An absorbent mass with oil or viscous fluid therein or supplied thereto disclosed for gas separation, or a solid or nonabsorbent sheet disclosed in a gas separating environment is not classified in Class 239, but is classifiable in either Class 96 or Class 261, depending on the nature of the liquid source. (See also the search class note to Class 261 in this section).
241, Solid Material Comminution or Disintegration, 68 for apparatus for combinations of comminution and separation of solids from a gas. Class 241 is superior to the material separation classes and, therefore, provides for apparatus in which comminution is combined with means to separate the material into classes according to the physical characteristics of its components before, during, or after the comminuting operation. Class 96 takes apparatus, such as deflectors or the like, that may act to comminute material as a secondary or incidental function of what is basically a holding back or separating procedure (e.g., disintegration or attrition of ignited particles in spark arresters, etc.). Such apparatus are classified on the basis of their essential function in Class 96.
242, Winding, Tensioning, or Guiding, 550 for unwinding an elongated material, and subclasses 570+ for a coil holder of
general use.
250, Radiant Energy, 281 for apparatus for the ionic separation of materials utilizing the charge-to-mass ratios of particles. See particularly subclasses 294+ for apparatus to subject the ionized particles to the effects of an electric or magnetic field, which causes the particles to travel through a curved trajectory, the particles of a certain charge-to-mass ratio having a trajectory different from those particles having other charge-to-mass ratios.
252, Compositions, 189 for substances (e.g., liquid sorbent compositions, etc.) for use in absorbing or binding carbon monoxide (CO), sulfur (S), negative elements, or acids; subclass 193 for substances (e.g., liquid sorbent compositions, etc.) for use in absorbing or binding ammonia, alkalis, or other bases; and subclass 194 for substances (e.g., liquid sorbent compositions, etc.) for use in absorbing or binding water.
261, Gas and Liquid Contact Apparatus, appropriate subclasses, for apparatus for degasifying liquid (e.g., deaerating feed water heater, etc.) wherein the liquid is merely contacted with a gas in a chamber or space for deaeration thereof; for apparatus wherein a gaseous fluid mixture is contacted with a liquid spray, sheet, stream, or bath to precipitate dust or to sorb a constituent from the gaseous fluid mixture; for apparatus comprising a nonabsorbent element on which a gaseous fluid mixture is contacted with a liquid if the element is continuously supplied with a liquid or is continuously moved into and out of a liquid bath or supply; and for apparatus comprising an absorbent porous sheet or mass on which a gaseous fluid mixture is contacted with a liquid if the sheet or mass is: (a) continuously supplied with liquid, (b) cyclically or periodically moved through a liquid reservoir, (c) maintained wet by liquid applying means, or (d) moistened by maintaining some part of a continuous wick type member immersed in liquid, by following the law of the machine, or during normal operation of a gas contacting function. Note that under the provisions of (a) and (b) there must be no affirmative means to dry the sheet or mass, nor means to assure a dry condition of the sheet or mass before gas flow is resumed or the sheet or mass is returned to the gas contacting position. If apparatus for degasifying liquid by contact with a gas has other means to cause gas separation of the liquid with gas entrained therein, of the separated gas, or of the separated liquid, then the apparatus is classified in Class 96. If apparatus in which a gaseous fluid mixture is contacted with a liquid to precipitate dust or to sorb a constituent from the gaseous fluid mixture has other means to cause gas separation or has means to treat the contact liquid, then the apparatus is classified in Class 96.
(1) Note. Apparatus for separating ammonia (NH[subscrpt]3[end subscrpt]) or acid anhydrides (CO[subscrpt]2[end subscrpt], SO[subscrpt]2[end subscrpt],
etc.) from a gas by mere contact with a liquid is classified in Class 261.
(2) Note. Processes for gas separation by contacting a gaseous fluid mixture with a liquid and processes of degasifying a liquid are classified in Class 95.
266, Metallurgical Apparatus, 144 for metallurgical apparatus combined with gas separating means and subclasses 200+ for apparatus for treating liquefied metal. See particularly subclasses 208+ for apparatus for treating liquefied metal by application of vacuum that may include degasification of the liquefied metal.
296, Land Vehicles: Bodies and Tops, 77.1 for storm-front shields, aprons, or robes used to protect the occupants of vehicles from storm or wind coming from the direction in which the vehicle is moving.
323, Electricity: Power Supply or Regulation Systems, subclasses 220-354 for voltage magnitude control means not restricted to electrostatic precipitator systems.
363, Electric Power Conversion Systems, appropriate subclasses, especially 59, 74+, and 100 for current rectification systems not restricted to electrostatic precipitator systems.
376, Induced Nuclear Reactions: Processes, Systems, and Elements, for apparatus for induced nuclear reactions combined with means for reaction product treatment. See particularly 146, 189, 195, 198, and 201. See subclasses 308+ for apparatus including fission reactor material treatment and subclasses 370+ for reactor structures with means for separation of a vapor.
383, Flexible Bags, 42 for bag closures and appropriate subclasses for bags not used as filter bags for gas separation.
406, Conveyors: Fluid Current, 154 for apparatus to convey solid material in a fluid current with means to separate the solids from the fluid at the conveyor outlet.
415, Rotary Kinetic Fluid Motors or Pumps, subclass 121.2 for a pump or motor combined with means to separate solids from a gaseous working fluid and subclasses 169.2+ for a pump or motor combined with means to separate moisture vapor or liquid from a gaseous working fluid.
417, Pumps, appropriate subclasses for pumps combined with upstream filtering or separating means specifically disclosed as protecting the pump and also for pumps combined with separators if any of the separated constituents are fed back or applied to the pump. This includes, for example, lubricant, coolant, or an impelling fluid which is separated from an impelled fluid, as in a jet pump. Class 417 takes jet
pumps for flues combined with a spark arrester, because the combination of a jet pump and a spark arrester is considered to be a perfecting feature of the pump. See Class 417, subclass 156.
(1) Note. A system for evacuating a space and in which a trap is included for preventing back-streaming or back-migration of molecules from a pumping area to the space being evacuated and which operates in the manner of a Class 96 gas separator will be considered a gas separator whether or not the apparatus is so identified. It will be noted that with the trap positioned between the space and the pump, separation would occur with gas flowing in either direction (i.e., from the space to the pump or from the pump to the space), if the fluid is separable.
Classification of the different combinations which may be claimed is as follows: (a) A Class 96 type trap or separator, per se, identified either as a pump or a separator is classified in Class 96. (b) A separator or molecule trap of the Class 96 type combined with a pump to evacuate space is classified in Class 96 unless there is some specific relationship between the separator or trap and the pump (other than the mere pumping of the fluid to and through the trap). As a nonlimiting example, if the separated material is conducted to a pump element for lubrication, cooling, etc., then classification is in Class 417. (c) A separator or molecule trap of the Class 96 type combined with a pump and a space being evacuated is classified in Class 96 unless there is some special separable connection of the type recognized in Class 141 for receiver coaction, in which case classification is in Class 141, regardless of any interrelationship between the pump and the separator or trap as set forth in (b) above. (d) A pump claimed in combination with nominally claimed filter or separator will be classified in Class 417. (a), (b), and (c) do not take into account the combination with heat exchanging or refrigerating means provided for in Classes 62 and 165, for which see the search class notes set out in other parts of this section.
418, Rotary Expansible Chamber Devices, for rotary expansible chamber type pumps. The line between Class 96 and Class 418 is the same as set forth above for Class 417.
422, Chemical Apparatus and Process Disinfecting, Deodorizing, Preserving, or Sterilizing, for apparatus for (a) carrying out chemical reactions, (b) preparing or treating chemical compounds or compositions, even though only a physical reaction is discernible, and (c) performing an analysis which involves either a chemical reaction or a physical reaction not elsewhere provided for. See 88 for apparatus for quantitative or qualitative chemical analysis of a gas sample including means for absorbing or adsorbing the gas sample or that portion to be tested into or onto liquid or solid media. See subclasses 120+ for apparatus for (a) taking the odor out of or masking the odor of or (b) chemical purification of a life-sustaining environmental gas
(for breathing apparatus) or the chemical generation of the same. See subclasses 168+ for apparatus for the modification of a waste gas, prior to its discharge into the atmosphere, by chemical reaction to reduce the pollutant content thereof. Class 96 takes the combination of preserving, disinfecting, or sterilizing means and gas separation means of the type that meets the requirements for gas separation apparatus in the definition for Class 96. The gas separating means may be claimed by name only, provided such named device is disclosed as being more than a mere supporting or treating means for a preserving, disinfecting, or sterilizing substance (see, e.g., Class 96, subclasses 223+).
428, Stock Material or Miscellaneous Articles, appropriate subclasses for stock material which may inherently perform a gas separating function (e.g., a structurally defined web or sheet including apertures, etc.). However, stock material when positively stated as being for gas separation will be found in Class 96 (see Class 55, 522 ).
435, Chemistry: Molecular Biology and Microbiology, 283.1 for apparatus claimed or solely disclosed for using a microorganism or enzyme to synthesize a chemical product or for treating a material with a microorganism or enzyme to separate, liberate, or purify a preexisting substance.
451, Abrading, subclass 453 for an accessory usable with abrading means for collecting particles coming from a grinding wheel or work during operation of the grinding wheel.
454, Ventilation, appropriate subclasses for ventilated structures, per se, or combined with a gas separating operation. Class 454 includes devices such as screens or gridlike members (e.g., bird screens, etc.), chimney caps, diffusion type air registers, hoods, offtakes, louvers, and pipe caps which function to control rather than to separate gas.
493, Manufacturing Container or Tube From Paper; or Other Manufacturing From a Sheet or Web, 39 for cigarette filter making methods or apparatus; see especially subclasses 47+ for methods or apparatus to assemble dissimilar filter materials (e.g., fiber and powdered charcoal, etc.) and subclass 941 for a cross-reference art collection for operations involving the construction of a filter.
494, Imperforate Bowl: Centrifugal Separators, for apparatus for the breaking up or subdividing of material, which material comprises a mixture of fluids or fluent substances, into two or more components by utilizing a rotatable, receptaclelike member having a generally solid wall, and commonly termed a bowl, for subjecting the material to centrifugal force. Thus, gas separation apparatus that is an imperforate bowl, centrifugal separator is proper for Class 494.
502, Catalyst, Solid Sorbent, or Support Therefor: Product or Process of Making, 60 for zeolite compositions, per se, and for processes of making zeolite compositions, and subclasses 400+ for other solid sorbent compositions, per se, and for processes of making solid sorbent compositions. Class 502 will take zeolite or other solid sorbent compositions having details of the physical characteristics of the composition itself (e.g., porosity, particle size, etc.). Class 502 will also take zeolite or other solid sorbent compositions that are layered, laminated, or otherwise affixed to another zeolite or other solid sorbent composition or to a support material. Class 96 takes apparatus having (a) an inlet for the fluid mixture to be treated, (b) a means effective to cause separation into constituent parts, and (c) an outlet for at least one constituent separate and distinct from an outlet for another constituent or a single outlet used at different times to remove the separated constituents. The means effective to cause separation into constituent parts confines the zeolite or other solid sorbent composition inside an enclosure that contains the fluid mixture being separated. Class 96 also takes filter elements having zeolite or other solid sorbent compositions held in an open structure or rim that encases, holds, or borders the zeolite or other solid sorbent composition or held on a skeletal structure.

GLOSSARY:
CHARGE GAS, GAS, OR SYSTEM FLUID
(Terms used in Class 55 subclass titles and definitions). These terms are used synonymously and mean the inlet mixture of gas carrying therein solids or fluids, the mixture during separation, or a gaseous constituent after separation.
DETECT
The term "detect," which is used in many of the control subclasses, is used in both a quantitative and a qualitative sense. This means that a definite measurement of a process variable is made (e.g., temperature, pressure, concentration, etc.) or that the presence of a particular event is determined (e.g., presence of sparking, change in liquid level determined by position of float, etc.).
FILTER
An article or mass of material made of closely spaced or intimately arranged intermeshed or unconnected fibers, elements, strands, or particles that collectively act as a barrier to physically retain at least one constituent of a fluid mixture on its surfaces or in the spaces between the fibers, elements, strands, or particles while permitting passage of the remaining constituents.
A filter has no "chemical" affinity for a constituent of a fluid mixture. The retention of the constituent by the filter depends upon a mechanical entrapment of solid or liquid
particles because of their relatively large size compared with the interstices or spaces between individual fibers, elements, strands, or particles. The retained particles can be removed by brushing, wiping, shaking, or similar mechanical action.
FLUID MIXTURE
The phrase "fluid mixture" is used throughout the definitions to mean (a) a gas and solid or liquid particles entrained therein, (b) a liquid and gas entrained therein, or (c) a plurality of gases.
GAS
Matter of very low density and viscosity, relatively great expansion and contraction, with changes in pressure and temperature, that is readily diffusive, with a tendency to expand indefinitely, with molecules in free movement. The term "gas" includes "vapor" (q.v.).
GASEOUS FLUID MIXTURE
The phrase "gaseous fluid mixture" is used throughout the definitions to mean (a) a gas and solid or liquid particles entrained therein or (b) a plurality of gases.
LIQUID SORBENT
A liquid capable of retaining part of a fluid mixture with which it is contacted. The action in most cases is that of selective retention (i.e., the sorbent removes only that part of the fluid mixture for which it has the greatest affinity).
REGENERATION
Restoration of the separatory material to the condition it was in before the separatory process.
SEPARATING APPARATUS
The entire gas separating means, which consists of all of the apparatus parts related to gas separation and includes apparatus parts that are in addition to the separator.
SEPARATING MEDIUM (MEDIA)
Liquid sorbent or means that effects the separation into constituent parts (e.g., deflector, filter, molecular sieve, sorber, etc.). (Media has been used in the singular and in the plural.)
SEPARATOR
The portion of the apparatus that consists of a separating medium and the structure supporting, retaining, or
substantially confining the separating medium.
SOLID SORBENT
A solid sorbent is a solid material which separates a constituent (e.g., a gas, vapor, etc.) from a fluid mixture containing such constituents in a "quasi-chemical" manner. The action in most instances is that of selective retention (i.e., the sorbent removes only the part of the fluid mixture for which it has the greatest affinity). The retained constituent cannot be removed by shaking, brushing, or similar mechanical action, but generally can be removed by heating, pressure reduction, or use of a stripping or denuding fluid.
TREATMENT
(a) With respect to the class subject matter, the term is restricted to reversible and nonchemical changes in physical characteristics of the fluid mixture or a separated constituent (e.g., heating, cooling, humidity control, agitating, pressure regulation, etc.). (b) With respect to the media used to perform the gas separation or to a material used to condition the fluid mixture for separation, the term may include chemical preparation, reconditioning, or reaction.
VAPOR
The gaseous state of matter that is liquid or solid under a temperature of 0 deg.C and pressure of 760 mm Hg.

MAGNETIC SEPARATING MEANS:
This subclass is indented under the class definition. Apparatus having means to produce magnetic lines of force in order to separate a constituent or to aid the separation of a constituent from a fluid mixture.
(1) Note. The means may be either a permanent magnet or an electromagnet.

SEE OR SEARCH CLASS:
95, Gas Separation: Processes, 43 for a process using the selective diffusion of gases through a solid, liquid, or gaseous barrier, such as a semipermeable membrane.
210, Liquid Purification or Separation, subclass 96.2, 257.2, and 321.6+ for apparatus having membranes or dialyzers for separating liquids and subclasses 500.21+ for semipermeable
membranes used in the separation of liquids.
215, Bottles and Jars, subclass 261 for closures for bottles and jars having a barrier permeable to gas and impermeable to liquid.

Immobilized liquid membrane:
This subclass is indented under subclass 4. Apparatus in which the barrier to gas diffusion is a liquid that is supported or immobilized in or on a porous medium.

SEE OR SEARCH CLASS:
95, Gas Separation: Processes, subclass 44 for corresponding processes. Patents are not cross-referenced from Class 95, subclass 44 to this subclass based only on disclosure. Therefore, relevant disclosures of gas separation apparatus may be found in the process area.

Membrane to degasify liquid:
This subclass is indented under subclass 4. Apparatus which is used to separate gas entrained in a liquid (e.g., by selectively allowing the gas to pass through a barrier, such as a membrane, etc.).

SEE OR SEARCH THIS CLASS, SUBCLASS:
155 for apparatus effecting the degasification of a liquid without utilizing the selective diffusion of gases.

SEE OR SEARCH CLASS:
95, Gas Separation: Processes, subclass 46 for corresponding processes. Patents are not cross-referenced from Class 95, subclass 46 to this subclass based only on disclosure. Therefore, relevant disclosures of gas separation apparatus may be found in the process area.

Plural separate barriers:
This subclass is indented under subclass 4. Apparatus comprising two or more distinctly separate barriers (e.g., membrane stack, etc.).

Parallel hollow fibers or cylinders (e.g., bundled, etc.):
This subclass is indented under subclass 7. Apparatus comprising a plurality of hollow fibers or cylinders, where the hollow fibers or cylinders are usually small-diameter tubes bundled for parallel gas flow.

SEE OR SEARCH CLASS:
210, Liquid Purification or Separation, subclass 323.2 for plural distinct tubular separators and subclass 500.23 for hollow fibers or cylindrical semipermeable membranes used in the purifying or separating of liquids.

Barriers connected in series:
This subclass is indented under subclass 7. Apparatus in which at least two separate barriers are arranged in series for sequential gas diffusion or separation.

Hollow fiber or cylinder:
This subclass is indented under subclass 4. Apparatus in which the gas is diffused through the wall of a hollow fiber or cylinder (e.g., tube, etc.).

SEE OR SEARCH CLASS:
210, Liquid Purification or Separation, subclass 500.23 for hollow fibers or cylindrical semipermeable membranes used to purify or separate liquids.

Plural layers (e.g., laminated barrier, etc.):
This subclass is indented under subclass 4. Apparatus in which the barrier for gas diffusion comprises two or more distinguishable layers.
(1) Note. The layers or laminates may be of similar composition. Where the barrier has been formed by evaporation
of one or more components to result in a surface layer depleted in these components and the surface layer is distinguishable from the remaining barrier thickness upon subsequent inspection, the barrier is taken to be composed of at least two distinguishable layers.
(2) Note. Plural layer (or laminated) membranes are often referred to as composites. However, the use of this term as applied to classification in this subclass does not include a single porous barrier material impregnated with a second material unless enough of the second material remains on the exterior of the single porous barrier material to form a distinguishable coating or second layer.

Organic compound containing layer:
This subclass is indented under subclass 11. Apparatus in which at least one of the distinguishable layers contains an organic compound.

SEE OR SEARCH CLASS:
210, Liquid Purification or Separation, 500.27 for semipermeable membranes containing an organic compound which are used for purifying or separating liquids.

Ring containing organic compound:
This subclass is indented under subclass 12. Apparatus in which at least one of the distinguishable layers contains an organic compound that is cyclic.

SEE OR SEARCH THIS CLASS, SUBCLASS:
14 for gas diffusion membranes composed of a single layer and having at least one ring containing organic compound.

SEE OR SEARCH CLASS:
210, Liquid Purification or Separation, 500.28 for semipermeable membranes containing a cyclic organic compound which are used for purifying or separating liquids.

Membrane having ring containing organic compound:
This subclass is indented under subclass 4. Apparatus in which the barrier has at least one cyclic or ring containing organic compound.

SEE OR SEARCH THIS CLASS, SUBCLASS:
13 for gas diffusion apparatus with plural layers in which at least one of such layers has a ring containing organic compound.

SEE OR SEARCH CLASS:
210, Liquid Purification or Separation, 500.28 for semipermeable membranes containing a cyclic organic compound which are used for purifying or separating liquids.

ELECTRIC FIELD SEPARATION APPARATUS (E.G., ELECTRICAL PRECIPITATOR, ELECTROSTATIC TYPE, ETC.):
This subclass is indented under the class definition. Apparatus in which a constituent of the fluid mixture is separated or precipitated by an electric field or discharge means and includes an electrode arranged to emit, collect, or control movement of charged particles (e.g., electrical or Cottrell precipitators, electrostatic type, etc.); and subcombinations thereof (e.g., electrodes for such apparatus, etc.).
(1) Note. Treatment by an electric field to agglomerate or coalesce constituents of the fluid mixture, where no provision for separation or precipitation, as such, is described, is classified in this subclass if the disclosure relates to gas separation and the ultimate use of the apparatus is for gas separation.
(2) Note. This subclass is the collecting home for means for insuring nonconducting properties of the apparatus, other than mere conductor sheath. Thus, patents claiming such means with only nominal recitation of other features are classified in this subclass rather than the indented subclasses, and other patents with significant disclosures of such means are cross-referenced to this subclass. However, patents concerning insulation and having a disclosure or claims pertaining to electrode retaining or supporting means are not placed in this subclass but are found in subclass 88.
(3) Note. The line between Class 96 and the applicable electrical classes is based on the amount of disclosure. If there is a general utility or multiple purpose disclosure and the claims are not limited to electric field separation apparatus for this class (such as by including precipitator electrodes), then classification is in the appropriate other class.

SEE OR SEARCH THIS CLASS, SUBCLASS:
3 for electric field separation apparatus combined with magnetic separating means.
88 for insulation features combined with electrode retaining or supporting means.
223 for gas separation apparatus combined with sterilizing means.

SEE OR SEARCH CLASS:
95, Gas Separation: Processes, 57 for processes involving an electric field for separating fluid mixtures.
174, Electricity: Conductors and Insulators, 137 for insulators.
204, Chemistry: Electrical and Wave Energy, appropriate subclasses; particularly 660+ for similar apparatus dealing with the electrical separation of liquids and degasification of liquid aided by electrical discharge involving the conversion of constituents to other compounds. When such chemical conversion is in doubt, placement of electrical apparatus for degasifying liquid is proper for Class 96.
210, Liquid Purification or Separation, subclass 243 for liquid separation apparatus with electrical insulating or electricity discharging means.
250, Radiant Energy, 281 for processes and apparatus for separating ionized material based on the differing charge-to-mass ratios of such material.
313, Electric Lamp and Discharge Devices, appropriate subclasses for electric space discharge devices, especially 231.01 for such discharge devices which have means for passing a fluent material between the discharge electrodes.
315, Electric Lamp and Discharge Devices: Systems, appropriate subclasses for miscellaneous systems for supplying electrical energy to electric space discharge devices of the gas or vapor ionization type.
327, Miscellaneous Active Electrical Nonlinear Devices, Circuits, and Systems, appropriate subclasses and particularly 530 for miscellaneous circuits having a specific source of supply or bias voltage.
361, Electricity: Electrical Systems and Devices, 227 for particle charging means and 230+ for ionizing means which are not solely disclosed in connection with the separation of a gaseous fluid mixture.
422, Chemical Apparatus and Process Disinfecting,
Deodorizing, Preserving, or Sterilizing, 22 for processes of disinfecting, deodorizing, preserving, or sterilizing using direct contact with electrical or electromagnetic radiation, and subclasses 186.04+ for electrostatic field or electrical discharge apparatus for chemical treatment not combined or associated with gas separation apparatus of the type found in Class 96, subclasses 223+. Also, see the search class note to Class 422 at the beginning of this class.

And radioactive or ultraviolet light ionizer:
This subclass is indented under subclass 15. Apparatus having means to ionize a gaseous fluid mixture either by radioactive or ultraviolet light means.

SEE OR SEARCH THIS CLASS, SUBCLASS:
223 for nonelectrical separation apparatus combined with sterilizing means.

Electric charge produced by friction (e.g., by gas flow, etc.):
This subclass is indented under subclass 15. Apparatus in which electrification of a separator part is accomplished by friction between two solid bodies or by flow of gas across or through a solid.
(1) Note. Placing a member in an electric field to charge such member is not included in this subclass.

SEE OR SEARCH THIS CLASS, SUBCLASS:
16 for electric field separation apparatus including radioactive or ultraviolet light ionizers.
80 for electric field separation apparatus with voltage supply means or circuitry.

SEE OR SEARCH CLASS:
55, Gas Separation, subclass 360 for means to ground a filter and serving to prevent shock hazard, the static electricity having no precipitating or separating function.
310, Electrical Generator or Motor Structure, 308 ; particularly subclass 310 for charge accumulating electrostatic generators of the friction type.

With control means responsive to sensed condition:
This subclass is indented under subclass 15. Apparatus in which means are provided to detect an apparatus or a process characteristic or change therein and to control or regulate operation of the apparatus or process based on the detected characteristic or change therein.
(1) Note. In this subclass and the subclasses indented hereunder, a single means may be used both to detect the characteristic or a change therein and to implement an action in the apparatus based upon the detected characteristic or change therein. There must be a positive action made by the apparatus because of the detected characteristic or change therein. An example is a pressure relief valve in which a certain pressure must be reached before the valve opens to relieve pressure differential across the valve. Another example is a thermostat with a bimetallic element in which a certain temperature must be reached before the element is deformed enough to trip a switch, thus implementing a control action in the apparatus as a result of the temperature or change therein. Apparatus in which no positive action is made by the single means as a result of the detected characteristic or change therein is not classified in this subclass or in the subclasses indented hereunder, but is classified below. An example of such means would be an ammeter for recording spikes in electric current to denote sparking events, but without means for implementing any reaction in the apparatus (e.g., to reduce electrode voltage, etc.) as a result of such current spikes.

SEE OR SEARCH THIS CLASS, SUBCLASS:
25 for electric field separation apparatus with programmed, cyclic, or time responsive control means not responsive to a sensed condition.
26 for electric field separation apparatus with measuring, indicating, signal, or alarm means.
30 for electric field separation apparatus with cleaner and interrelated shutdown or voltage adjustment means.
80 for electric field separation apparatus with voltage supply or circuitry which is not specifically used to control operation of the apparatus.
102 for chromatography type apparatus with control means responsive to sensed condition.
109 for solid sorbent apparatus with control means responsive to sensed condition.
156 for apparatus degasifying liquid with control means responsive to sensed condition.
397 for gas separation apparatus with automatic control means for gas or nongaseous constituent discharge and subclasses 417+ for gas separation apparatus with signals, indicators, measuring, or testing means.

SEE OR SEARCH CLASS:
95, Gas Separation: Processes, 2 for electric field separation processes with control responsive to sensed condition, subclass 25 for processes with recording or signaling condition, and subclass 26 for processes with timing of operation.
340, Communications: Electrical, 500 for automatic electrical condition responsive indicating systems; particularly subclasses 632+ for gas responsive devices.

Concentration or temperature sensing means:
This subclass is indented under subclass 18. Apparatus in which means are provided to detect the amount of a constituent present (e.g., dust, humidity, etc.) or a change therein in the fluid mixture or the temperature or a change therein of the fluid mixture under treatment and to control or regulate the operation of the apparatus based on the detected characteristic or change therein.

SEE OR SEARCH THIS CLASS, SUBCLASS:
407 for gas separation apparatus having temperature or humidity responsive automatic control means for gas or nongaseous constituent discharge.

SEE OR SEARCH CLASS:
95, Gas Separation: Processes, subclass 3 and 4 for corresponding processes with control responsive to concentration and temperature, respectively; subclasses 8+ and 14+ for nonelectrical separation processes with control responsive to concentration and temperature, respectively.
236, Automatic Temperature and Humidity Regulation, for automatic temperature or humidity control means, per se.

Arc, spark, or flashover sensing means:
This subclass is indented under subclass 18. Apparatus in which means are provided to detect the presence or frequency of sparking discharge in the gaseous fluid mixture (e.g., arc or flashover of current bursts between differently charged parts, such as between discharge and collector electrodes, etc.) and to control or regulate the apparatus based on the detected sparking.
(1) Note. A sparking event or its frequency may be detected indirectly (e.g., by detecting short bursts of increasing system electrical current or decreasing electrode voltage, etc.), but must be specifically claimed to be classified in this subclass.

SEE OR SEARCH CLASS:
95, Gas Separation: Processes, subclass 5 for electric field separation processes with control responsive to sensed sparking.

Current sensing means:
This subclass is indented under subclass 20. Apparatus in which means are provided to detect electrical current or a change therein and to control or regulate the operation of the apparatus based on the detected electrical current or change therein.

SEE OR SEARCH THIS CLASS, SUBCLASS:
22 for electric field separation apparatus with control means responsive to electrical current, but without means responsive to arc, spark, or flashover.

Current sensing means:
This subclass is indented under subclass 18. Apparatus in which means are provided to detect electrical current or a change therein and to control or regulate the operation of the apparatus based on the detected electrical current or change therein.

SEE OR SEARCH THIS CLASS, SUBCLASS:
21 for electric field separation apparatus with control means responsive to arc, spark, or flashover and also responsive to electrical current.

SEE OR SEARCH CLASS:
95, Gas Separation: Processes, subclass 6 for corresponding processes with control responsive to sensed electrical current.

And voltage sensing means:
This subclass is indented under subclass 22. Apparatus in which means are provided to detect voltage or a change therein and to control or regulate the operation of the apparatus based on the detected voltage or change therein.

SEE OR SEARCH THIS CLASS, SUBCLASS:
24 for electric field separation apparatus with control means responsive to voltage, but without means responsive to arc, spark, flashover, or electrical current.

SEE OR SEARCH CLASS:
95, Gas Separation: Processes, subclass 7 for electric field separation processes with control responsive to sensed voltage.

Voltage sensing means:
This subclass is indented under subclass 18. Apparatus in which means are provided to detect electrode voltage or a change therein and to control or regulate the apparatus based on the detected voltage or change therein.

SEE OR SEARCH THIS CLASS, SUBCLASS:
23 for electric field separation apparatus with control means responsive to voltage and electrical current.

SEE OR SEARCH CLASS:
95, Gas Separation: Processes, subclass 7 for electric field separation processes with control responsive to sensed voltage.

With programmed, cyclic, or time responsive control means:
This subclass is indented under subclass 15. Apparatus which
is provided with control means not directly responsive to a sensed condition for (a) storing coded instructions or other data necessary to regulate operation of the treating apparatus, (b) repetitively regulating a sequence of operational steps performed in or by the treating apparatus, or (c) causing various system operations to occur according to preset timing sequences or to last for predetermined durations (e.g., timer switches, etc.).
(1) Note. This subclass includes any control means which maintains an operating condition, predetermines apparatus operation, or regulates repetition.

SEE OR SEARCH THIS CLASS, SUBCLASS:
18 for electric field separation apparatus with control means responsive to sensed condition.
26 for electric field separation apparatus with measuring, indicating, signal, or alarm means.
30 for electric field separation apparatus with cleaner and interrelated shutdown adjustment means; particularly subclass 31, including means for sequential operation.
80 for electric field separation apparatus with voltage supply or circuitry which is not specifically used to control operation of the apparatus.
103 for chromatography type separation apparatus with programmed, cyclic, or time responsive control means.
115 for solid sorbent apparatus with programmed, cyclic, or time responsive control means.
424 for nonelectrical gas separation apparatus with timing or changeable programming means.

SEE OR SEARCH CLASS:
95, Gas Separation: Processes, subclass 26 for gas separation processes with timing of operation.

With indicating, signal, or alarm means:
This subclass is indented under subclass 15. Apparatus which is provided with means to indicate a characteristic or change therein (e.g., of the fluid mixture, a separated constituent, or the apparatus, etc.); or means to signal or alert the status of such a characteristic.

SEE OR SEARCH THIS CLASS, SUBCLASS:
18 for electric field separation apparatus with control means responsive to sensed condition.
25 for electric field separation apparatus with programmed, cyclic, or time responsive control means.
117 for solid sorbent apparatus with indicating, signal, or alarm means combined with programmed, cyclic, or time responsive control means.
417 for gas separation apparatus with signals, indicators, measuring, or testing means.

SEE OR SEARCH CLASS:
73, Measuring and Testing, for measuring and testing procedures and apparatus.
95, Gas Separation: Processes, subclass 25 for gas treating processes with recording or signaling condition.
116, Signals and Indicators, particularly 67 for alarms and 200+ for indicators.
374, Thermal Measuring and Testing, for thermal measuring methods and devices, particularly 100 for thermometers and similar devices.

With means to add charged solid or liquid particles to gaseous fluid mixture:
This subclass is indented under subclass 15. Apparatus which has means for commingling a solid or liquid agent carrying an electrical charge with the gaseous fluid mixture being separated, where the solid or liquid agent ionizes, agglomerates, or collects constituents of the mixture or otherwise electrically treats the gaseous fluid mixture.
(1) Note. Apparatus including a charged fluidized bed for treatment of the gaseous fluid mixture is also found in this subclass.

SEE OR SEARCH THIS CLASS, SUBCLASS:
44 for electric field separation apparatus with wet film type electrodes in which liquid is directly applied to an electrode rather than being introduced into the gaseous fluid mixture as charged discrete liquid particles.
52 for electric field separation apparatus with means for vapor or liquid contact to treat a gaseous fluid mixture or a separated constituent.

SEE OR SEARCH CLASS:
95, Gas Separation: Processes, 58 for electric field separation processes with addition of solid, gas, or vapor to the gaseous fluid mixture; subclasses 64+ for electric field separation processes including separation by liquid addition to the gaseous fluid mixture; and subclasses 71+ for electric field separation processes with addition of liquid to the fluid mixture.
361, Electricity: Electrical Systems and Devices, 227 for means charging particles (e.g., fluid spray, etc.), and see the search note included there for other fields of search.

Electrode cleaner, apparatus part flusher, discharger, or wet collector (e.g., wet film electrode, etc.):
This subclass is indented under subclass 15. Apparatus which has (a) means to remove the constituent gathered on an electrode, (b) means to remove the separated constituent by air draft, suction, liquid, or positively acting discharging means from parts other than electrodes of the apparatus, or (c) means to provide a bath type collector or a moving liquid film for the surface of a collecting electrode.
(1) Note. The constituent which has been separated is usually nongaseous and adheres to the electrodes or has fallen therefrom onto a collecting means (e.g., a series of shelves, etc.).
(2) Note. A collector electrode with a moving liquid film thereon is included herein (see subclass 45 in particular) since a cleaning action is inherent during passage of the liquid film over the electrode, even though the cleaning action may not be specifically disclosed.

SEE OR SEARCH THIS CLASS, SUBCLASS:
228 for nonelectrical gas separation apparatus with means using liquid to clean the separating apparatus.
243 for nonelectrical gas separation apparatus with gas and liquid contact means.

SEE OR SEARCH CLASS:
15, Brushing, Scrubbing, and General Cleaning, for cleaning means of various types not specific to electric field separation apparatus.
55, Gas Separation, 282 for nonelectrical separating apparatus with means to clean a separating medium.
95, Gas Separation: Processes, 74 for electrical separation processes including cleaning of a collector electrode.
134, Cleaning and Liquid Contact With Solids, for various cleaning processes and apparatus, not specific to electric field separation apparatus.

Electrode or part thereof moved on or against another:
This subclass is indented under subclass 28. Apparatus arranged so that electrodes (discharge or collector) or parts thereof, in the case of sectionalized members, can move on or rub against each other or contact each other (e.g., by scraping or knocking against one another, etc.).

With shutdown or voltage adjustment means interrelated with cleaning (e.g., cutting off flow of gaseous fluid mixture or electrical current, etc.):
This subclass is indented under subclass 28. Apparatus having an interlock, electrical control, or blocking means (a) preventing normal operation of the apparatus or section thereof, as by cutting off or diverting the flow of gaseous fluid mixture or (b) disconnecting or effectively changing the voltage in an electrical circuit to the apparatus or section thereof, while the electrode cleaner is operating.

SEE OR SEARCH THIS CLASS, SUBCLASS:
80 for apparatus with details of voltage supply means or circuitry not specifically interrelated with cleaning.

Sequential operation:
This subclass is indented under subclass 30. Apparatus having means for cleaning the apparatus in sequence with shutdown or voltage adjustment.

SEE OR SEARCH THIS CLASS, SUBCLASS:
25 for electrical separation apparatus with programmed, cyclic, or time responsive control means.

Vibrating, jarring, or rapping means:
This subclass is indented under subclass 28. Apparatus having means to shake, jar, or set into a motion of small amplitude and relatively high frequency the electrode itself or its supporting means.

SEE OR SEARCH CLASS:
55, Gas Separation, subclass 300 for nonelectrical separation apparatus with vibrating, jarring, or rapping means for cleaning separating media.
95, Gas Separation: Processes, subclass 76 for electrical separation processes with electrode cleaning by scraping or vibrating.

Mounted on rotatable shaft (e.g., swinging arm or hammer, etc.):
This subclass is indented under subclass 32. Apparatus in which the vibrating, jarring, or rapping means is attached to a rotatable shaft (e.g., swinging arm or hammer, etc.) and is used to strike the electrode or its support or in some other way transfer impact so that collected constituents are dislodged from the electrode.

Having reciprocating rod or piston type activating or rapping means:
This subclass is indented under subclass 33. Apparatus in which a rod or piston is activated by or used to activate a rotatable means to accomplish transfer of an impact so that collected constituents are dislodged from the electrode.

SEE OR SEARCH THIS CLASS, SUBCLASS:
37 for reciprocating rod or piston type activating or rapping means not combined with rotatable means.

Activated by second swinging or rotatable means:
This subclass is indented under subclass 33. Apparatus in
which a shaft-mounted swinging or rotating means is caused to transfer vibration or impact to the electrode by motion of a second swinging or rotating means.

Magnet or solenoid activating means:
This subclass is indented under subclass 32. Apparatus in which a magnetic or electromagnetic means is used to induce vibration of the electrode or cause a second means to jar or rap the electrode or its support means, so that a collected constituent is removed.

SEE OR SEARCH CLASS:
335, Electricity: Magnetically Operated Switches, Magnets, and Electromagnets, 255 for magneto-mechanical devices of the core armature type for use as a rapping or jarring means for electrostatic precipitators, but not solely disclosed for use therein.

Reciprocating rod or piston type activating or rapping means:
This subclass is indented under subclass 32. Apparatus in which a rod or piston is moved in an axial direction to strike the electrode or to activate a second means to rap the electrode, so that a collected constituent is removed.

SEE OR SEARCH THIS CLASS, SUBCLASS:
34 for reciprocating rod or piston type activating or rapping means combined with rotatable means.

Horizontal striking means:
This subclass is indented under subclass 32. Apparatus in which means are provided to strike the electrode or its support means horizontally, in order to dislodge a collected constituent.

Movably mounted electrode:
This subclass is indented under subclass 28. Apparatus wherein the electrode is supported for movement relative to the apparatus either to effect or perfect cleaning of the apparatus.
(1) Note. There may be a plurality of electrodes, each being moved separately at the time of cleaning.

SEE OR SEARCH THIS CLASS, SUBCLASS:
93 for electric field separation apparatus with nonrigid support means for collector electrode.

SEE OR SEARCH CLASS:
55, Gas Separation, subclass 400 for nonelectrical separation apparatus with means mounted or supported for continuous motion.
95, Gas Separation: Processes, subclass 77 for electric field separation processes involving a continuously moving electrode.

Nonliquid contact cleaning means:
This subclass is indented under subclass 39. Apparatus in which the cleaning is accomplished by contact of the electrode with either a solid or gaseous agent.

Liquid bath for immersion of electrode:
This subclass is indented under subclass 39. Apparatus in which the movable electrode is dipped or partially dipped into a reservoir or body of liquid.

SEE OR SEARCH THIS CLASS, SUBCLASS:
231 for nonelectrical gas separation apparatus with liquid immersion cleaning means for separating media.

Endless belt carried or belt type electrode:
This subclass is indented under subclass 41. Apparatus in which the movable electrode comprises (a) an electrode means
affixed to a continuous running length member or (b) a running length (e.g., web, etc.) or belt type electrode.

Fluid contacting means (e.g., suction means, etc.):
This subclass is indented under subclass 28. Apparatus in which cleaning is accomplished by causing a nonsolid agent to contact the electrode or an apparatus part (e.g., by vacuum means, etc.) to remove a collected constituent.
(1) Note. The agent may be the gaseous fluid mixture from which the constituent is being removed or a gaseous fluid from which the constituent has been separated if applied to a part to be cleaned by pressure or suction means.

SEE OR SEARCH THIS CLASS, SUBCLASS:
228 for nonelectrical gas separation apparatus with means using liquid to clean the separating apparatus.

Liquid applying means for electrode (e.g., projection type, etc.):
This subclass is indented under subclass 43. Apparatus in which a liquid is brought into contact with electrode means to move thereon, whereby cleaning is effected.

SEE OR SEARCH THIS CLASS, SUBCLASS:
27 for electric field separation apparatus having means to add charged solid or liquid particles to the gaseous fluid mixture.
52 for electric field separation apparatus with means to treat a gaseous fluid by contacting it with a vapor or liquid.

SEE OR SEARCH CLASS:
95, Gas Separation: Processes, subclass 75 for electric field separation processes with electrode cleaning by liquid flushing.

Weir or overflow wet film type:
This subclass is indented under subclass 44. Apparatus having means to apply liquid to the electrode by permitting a supply of liquid to run over the retaining walls therefor and down over the electrode in overflowing fashion (as contrasted, for example, with immersion or projection spraying).
(1) Note. This subclass includes collector electrodes, per se (e.g., not claiming liquid supply means), defining structure limited or peculiar to liquid control either to wash down the electrode or to supply liquid to provide a film or wet-surfaced electrode.

Having movable spraying means for liquid:
This subclass is indented under subclass 44. Apparatus in which spray nozzles or other movable means are mounted for movement to distribute liquid across the electrode.

SEE OR SEARCH THIS CLASS, SUBCLASS:
281 for nonelectrical gas separation apparatus with movably mounted liquid distributor.

Including means to recirculate liquid:
This subclass is indented under subclass 44. Apparatus in which a flow path is provided to recycle at least a portion of the liquid used to wash the electrode.

Including baffle for directing gas flow:
This subclass is indented under subclass 44. Apparatus in which a baffle or deflector is arranged to funnel or redirect gas flow.
(1) Note. The treatment casing walls are not considered to serve as baffling means; in order to be classified in this subclass, additional baffle or deflector means must be arranged to affect gas flow.

SEE OR SEARCH THIS CLASS, SUBCLASS:
64 for electric field separation apparatus with perforated baffle or gas diffuser for contact with ionizing electrode or
uniform flow in treating zone.

SEE OR SEARCH CLASS:
55, Gas Separation, 434 for nonelectrical separation apparatus with deflector or impingement baffle.
95, Gas Separation: Processes, subclass 78 for electric field separation processes using baffling, deflection, or restriction of gas flow.

Cylindrical electrode:
This subclass is indented under subclass 44. Apparatus in which at least one electrode is formed in the shape of a cylinder.

Apparatus purging or flushing means using gas or liquid:
This subclass is indented under subclass 43. Apparatus in which gas or liquid is brought into contact with an apparatus part other than the electrodes (e.g., as in wet bottom precipitators, etc.) in order to effect cleaning.
(1) Note. This definition includes apparatus in which a gas draft of high volume is pumped through the apparatus to sweep it clean of accumulated deposits without special contact means expressly arranged for the electrodes.

SEE OR SEARCH THIS CLASS, SUBCLASS:
43 for electric field separation apparatus including special means expressly arranged to contact an electrode with cleaning gas.

Electrode scraping, brushing, or wiping means:
This subclass is indented under subclass 28. Apparatus having a solid agent for contacting the electrode to remove encrustation or residue.

SEE OR SEARCH THIS CLASS, SUBCLASS:
40 for electrodes moved against brushes, scrapers, or wipers for cleaning.

SEE OR SEARCH CLASS:
95, Gas Separation: Processes, subclass 76 for electric field separation processes involving constituent removal from collector electrodes.

With means for vapor or liquid contact (e.g., for gas separation, cooling, conditioning, etc.):
This subclass is indented under subclass 15. Apparatus having means to treat a gaseous fluid mixture or a separated constituent by contact with a liquid or vapor (e.g., for separation, heating, cooling, or conditioning, etc.).
(1) Note. Means to apply a fluid viscid coating or conditioning agent to electrodes are included, where the coating is substantially stationary, for the purpose of treating the gaseous fluid mixture or separated constituent.

SEE OR SEARCH THIS CLASS, SUBCLASS:
41 for electrode immersion means wherein the cleaning means may include a liquid useful for separation, such as a viscous liquid.
44 for liquid applying means and weir or overflow wet film type electrodes wherein the liquid is applied for cleaning.

SEE OR SEARCH CLASS:
95, Gas Separation: Processes, 58, 63+, and 71+ for electric field separation processes involving the addition of gas, vapor, or liquid to the gaseous fluid mixture under treatment.

Liquid spray means:
This subclass is indented under subclass 52. Apparatus in which means are provided to distribute or spray liquid in the gaseous fluid mixture to be treated.

Having alternating electrostatic field:
This subclass is indented under subclass 15. Apparatus in
which a constituent of the fluid mixture is treated or separated by passage of the fluid mixture through or along an alternating electrostatic field established between two electrode members by an alternating current.
(1) Note. Alternating field ionizers, agglomerators, coalescers, or collectors are classified herein.

SEE OR SEARCH CLASS:
95, Gas Separation: Processes, subclass 80 and 81 for electric field separation processes using pulsing or time-varying electric fields (e.g., AC, pulsed DC, etc.).

And serially arranged nonelectrical separator:
This subclass is indented under subclass 15. Apparatus having a separator other than an electric field separation apparatus arranged in the line of fluid flow.
(1) Note. This and indented subclasses do not provide for (a) baffle means for directing or spreading flow for distribution within the electric field separation apparatus or for contact with ionizing electrodes, or (b) electrodes modified to include baffling or flow distributing arrangements to direct a flowing stream. Such apparatus is more properly classified below.
(2) Note. This and indented subclasses do not include interstitial, porous, or foraminous collector electrodes that provide means for simultaneously filtering and precipitating contaminants from a flowing stream. Such apparatus is more properly classified below.
(3) Note. This and indented subclasses will take serially arranged separators even broadly recited coming within the definition.

SEE OR SEARCH THIS CLASS, SUBCLASS:
60 for flow distribution means and see (1) Note above.
65 for foraminous, porous, or interstitial collectors and see (2) Note above.

SEE OR SEARCH CLASS:
55, Gas Separation, 315 for nonelectrical separation apparatus with serial diverse separating media.
95, Gas Separation: Processes, 63 for electric field separation processes including a diverse type separator.

Bypass or modification of flow of gaseous fluid mixture to second stage:
This subclass is indented under subclass 55. Apparatus including means for (a) directing at least a portion of the gaseous fluid mixture to pass around the first separator or (b) modifying the quantity or quality of gaseous fluid mixture flowing from the first separator to the second.

SEE OR SEARCH CLASS:
55, Gas Separation, 309 for nonelectrical separation apparatus with means to bypass separating media.

Precedent nonelectrical separator:
This subclass is indented under subclass 55. Apparatus in which electric field separation apparatus follows downstream of the nonelectrical separator.

Separator is single porous filter:
This subclass is indented under subclass 57. Apparatus in which the nonelectrical separator is a single foraminous, porous, or perforated filter.

Total flow of gaseous fluid mixture through porous collector electrode:
This subclass is indented under subclass 55. Apparatus in which all of the gaseous fluid mixture to be treated flows through openings in a porous collector electrode.

SEE OR SEARCH THIS CLASS, SUBCLASS:
66 for electric field separation apparatus with total flow of gaseous fluid mixture through an interstitial or porous collector but without a serially arranged nonelectrical separator.

Including gas flow distribution means:
This subclass is indented under subclass 15. Apparatus having means or arrangements to direct, guide, or limit (including stopping or redirecting) gas flow within the apparatus.
(1) Note. The combination of electric field separation apparatus and a pump for merely causing gas to flow through the apparatus has not been recognized as flow distribution and is not specifically provided for in this section of the class.
(2) Note. This subclass and the subclasses indented hereunder are intended to provide for flow distribution means comprising (a) baffles and deflectors of all types and (b) other structures or fixtures besides flow conduits or the apparatus casing which are intentionally included or positioned to affect flow distribution or which would present a major inherent restriction to gas flow.

Spiralling inflow, centrifugal, or whirl generating surface means:
This subclass is indented under subclass 60. Apparatus having inlet means or means within the apparatus intimately associated with electrical elements to impart a centrifugal, vortical, or cyclonic flow pattern to the gas flow.

SEE OR SEARCH THIS CLASS, SUBCLASS:
55 for serially arranged diverse separators, one of which is a vortical separator.

SEE OR SEARCH CLASS:
55, Gas Separation, 434 for nonelectrical separation apparatus with deflectors and see the notes for related search areas.

For contact with ionizing electrode or uniform flow in treating zone:
This subclass is indented under subclass 60. Apparatus in which the means guide or direct gas flow (a) into close proximity to a discharging electrode for more complete
ionization or (b) for obtaining a less turbulent or more uniform distribution of flow through the apparatus.

Having means for driving gas flow (e.g., fan, blower, etc.):
This subclass is indented under subclass 62. Apparatus which includes a fan, blower, or other means to push or pull gas through the apparatus.

SEE OR SEARCH CLASS:
55, Gas Separation, subclass 383 for nonelectrical separation apparatus with remote fan or pump for gas flow, subclasses 437+ for nonelectrical separation apparatus with deflector and gas pump or fan, and subclasses 467+ for nonelectrical separation apparatus with other types of gas flow effecting means.

Perforated baffle or gas diffuser:
This subclass is indented under subclass 62. Apparatus which contains at least one baffle penetrated by holes for gas flow or other means to distribute or restrict the flow of gas.

SEE OR SEARCH THIS CLASS, SUBCLASS:
48 for apparatus with baffling means for gas and liquid applying means for an electrode.

SEE OR SEARCH CLASS:
55, Gas Separation, 434 for nonelectrical separation apparatus with deflector or impingement baffle.
95, Gas Separation: Processes, subclass 78 for electric field separation processes using baffling, deflection, or restriction of gas flow.

Collecting electrode modifies gas flow:
This subclass is indented under subclass 60. Apparatus in which the distribution means comprises one or more collecting electrodes shaped (e.g., as with a flow guide or directing means, etc.) or positioned to modify the flow of gas.
(1) Note. A plurality of collecting electrodes may be arranged in the apparatus to provide a gas flow pattern having special characteristics.

SEE OR SEARCH THIS CLASS, SUBCLASS:
60 for baffles and perforated ionizing electrodes for directing gas flow around or through ionizing electrodes.

Total flow of gaseous fluid mixture through interstitial or porous collector:
This subclass is indented under subclass 65. Apparatus in which the collecting electrode or electrodes are arranged and fashioned in such manner as to require all of the gaseous fluid mixture to flow through apertures, pores, or spaces of such electrode(s).
(1) Note. Arrangements of collector means requiring total flow of gaseous fluid mixture through such means as fibrous massed material, particulate material, and the like are considered to have inherent effect or influence on such flow.
(2) Note. Spaces must be small enough to have a substantial effect on flow of gaseous fluid mixture.

SEE OR SEARCH THIS CLASS, SUBCLASS:
59 for apparatus with total flow of gaseous fluid mixture through porous collector and serially arranged nonelectrical separator.
62 for apparatus with gas flow distribution means for contact with ionizing electrode.

Zigzag running length:
This subclass is indented under subclass 66. Apparatus in which the collecting electrode is shaped or positioned to provide a substantially uninterrupted surface of zigzag configuration.
(1) Note. Uninterrupted surfaces of zigzag configuration are read as having inherent flow controlling influence on the gaseous fluid mixture whether so stated in the patent or not.

SEE OR SEARCH CLASS:
55, Gas Separation, subclass 521 for nonelectrical separating means of zigzag shape.

Particle type collector:
This subclass is indented under subclass 66. Apparatus in which the gaseous fluid mixture passes through the apertures, pores, or spaces of a particle type collector.

Layered, laminated, or coated:
This subclass is indented under subclass 65. Apparatus in which the collecting electrode is composed of plural layers.
(1) Note. Only collectors with coatings substantial enough to compose complete and distinguishable layers are included in this subclass.

Plural separate electrode members aligned in direction of gas flow:
This subclass is indented under subclass 65. Apparatus in which a plurality of separate and distinct collecting electrode members are arranged in a serial fashion along the direction of gas flow (e.g., as in Figure 1 below, etc.). [figure] [caption]Figure 1
(1) Note. The separate electrode members may be attached to a common frame or housing, provided that this attachment is made only at the ends of each member. For this purpose, the "ends" of each member are defined as the points most distant from one another, measured perpendicular to the direction of gas flow.

SEE OR SEARCH THIS CLASS, SUBCLASS:
71 for segmented collecting electrodes.

Segmented electrode:
This subclass is indented under subclass 65. Apparatus in which the collecting electrode is composed of plural attached segments, abutted or overlapped, to form a single combined element (e.g., as in Figure 2 below, etc.). [figure] [caption]Figure 2

SEE OR SEARCH THIS CLASS, SUBCLASS:
72 for similar type collecting electrodes with attached projections.

Continuous electrode with integral or attached projections:
This subclass is indented under subclass 65. Apparatus in which the collecting electrode is composed of a continuous member with raised sections or connectedprojecting elements extending from its sides or edges (e.g., as in Figure 3 below, etc.). [figure] [caption]Figure 3

SEE OR SEARCH THIS CLASS, SUBCLASS:
67 for a zigzag running length collector arranged to allow total flow of gaseous fluid mixture therethrough.
71 for similar type collecting electrodes without integral or attached projections.

Flow distribution means for parallel sections:
This subclass is indented under subclass 60. Apparatus in which the flow distribution means is effective to restrict or distribute gas flow to or through plural electrode sections arranged to provide parallel flow paths.

With nonelectrical gas treating or conditioning means:
This subclass is indented under subclass 15. Apparatus which has nonelectrical means to alter a characteristic of the gaseous fluid mixture either before or during electric field separation or to alter a characteristic of the separated gas.

SEE OR SEARCH THIS CLASS, SUBCLASS:
18 for electric field treatment or conditioning apparatus
with control means responsive to sensed condition.
52 for electric field separation apparatus with vapor or liquid contacting means.
55 for electric field separation apparatus with serially arranged nonelectrical separator.
61 for electric field separation apparatus with spiralling inflow, centrifugal, or whirl generating surface means.

SEE OR SEARCH CLASS:
95, Gas Separation: Processes, 58, 63+, and 73 for electric field separation processes with nonelectrical gas treating or conditioning.

Plural diverse electric fields:
This subclass is indented under subclass 15. Apparatus in which there are provided separate electric fields for separation or treatment of the gaseous fluid mixture (a) by different voltages, currents, or electrode arrangements, or (b) by plural electric field separation units to provide effectively different electric fields arranged in the direction of flow of the gaseous fluid mixture.
(1) Note. A mere serial or continuous arrangement of electrodes to produce an elongated or repetitive field of one effective character is classified on some other basis.

SEE OR SEARCH THIS CLASS, SUBCLASS:
54 for electric field separation apparatus using an alternating electrostatic field.
55 for serially arranged, diverse type separators.
73 for flow regulating means for electric field separation sections in parallel flow arrangement.
83 for electrodes supported or retained by a casing or duct wall and not including features of voltage regulation or special arrangements for electric fields.

One or more electrodes common to plural fields:
This subclass is indented under subclass 75. Apparatus in which the electric fields are provided by means including
arrangements of electrodes such that one electrode or a group or array of similar electrodes is common to the separate electric fields.

Serially arranged ionizing and collecting or agglomerating fields:
This subclass is indented under subclass 75. Apparatus in which the electrode arrangement defines two electric fields, one downstream of the other in the direction of flow of the gaseous fluid mixture, the upstream field serving primarily to electrically charge particles in the gaseous fluid mixture and the downstream field serving primarily to collect or coalesce the charged particles.

SEE OR SEARCH THIS CLASS, SUBCLASS:
75 for electric field separation apparatus having plural diverse electric fields of other types.
76 for serially arranged ionizing and collecting or agglomerating fields in which one set of electrodes is common to both fields.

Adjacent parallel collector electrodes are differently charged:
This subclass is indented under subclass 77. Apparatus in which alternating collecting electrodes are charged to one potential (voltage) and the remaining plates to a second potential.
(1) Note. For example, if a positive potential is applied to the first alternating set, then either a negative potential or ground would be applied to the remaining electrodes, so that adjacent electrodes would be maintained at differing or opposite voltages.

Collecting electrodes are flat plates:
This subclass is indented under subclass 78. Apparatus in which the electrodes are in the form of flat plates.

SEE OR SEARCH THIS CLASS, SUBCLASS:
60 for flat plate collecting electrodes arranged to distribute gas flow.

With details of voltage supply means or circuitry:
This subclass is indented under subclass 15. Apparatus in which there is more than a nominal recitation of a circuit for voltage supply, power pack, or some other feature of electric conduction to an electrode.

SEE OR SEARCH THIS CLASS, SUBCLASS:
18 for voltage supply means involving control means responsive to a sensed condition.
30 for voltage adjustment means interrelated with cleaning.

SEE OR SEARCH CLASS:
323, Electricity: Power Supply or Regulation Systems, subclasses 220-354 for voltage magnitude control means not restricted to electric field separation apparatus as by the inclusion of electrodes.
327, Miscellaneous Active Electrical Nonlinear Devices, Circuits, and Systems, appropriate subclasses and particularly 530 for miscellaneous circuits having a specific source of supply or bias voltage.

Closure interlock or removable section:
This subclass is indented under subclass 80. Apparatus in which means are provided to make or break contact between a power source and an electrode by placement or removal of a movable member or section.
(1) Note. Closure interlocks or switches for deenergizing the electrodes upon gaining access to the apparatus and other nonautomatic electrical blocks are classified in this subclass.

Circuit portions:
This subclass is indented under subclass 80. Apparatus which includes specific power source components connected in the
form of a circuit.
(1) Note. Merely including a resistor, capacitor, or transformer, for example, is not considered specific enough for this subclass.

SEE OR SEARCH CLASS:
252, Compositions, 500 for compositions specialized for conducting electricity.

Electrode retaining or supporting means:
This subclass is indented under subclass 15. Apparatus having means to sustain one or more electrodes against gravity in an operative position in the apparatus.
(1) Note. For classification herein, at least some modification of the electrode for retaining it or some mechanical coupling feature as in the case of replaceable units (e.g., a slidably retained assembly, etc.) must be specified.
(2) Note. The electrode means may be (a) retained in a unitary assembly independent of the apparatus casing or (b) supported directly by walls of the apparatus casing.

Plural electrode unit assembly type (e.g., unitized, etc.):
This subclass is indented under subclass 83. Apparatus in which plural electrodes are maintained in a spaced relationship and are retained as a unit assembly to thereby permit simultaneous movement into or out of operative position within the apparatus.

Disposable (e.g., collapsible or foldable cardboard, etc.):
This subclass is indented under subclass 84. Apparatus in which the unit assembly (e.g., collapsible or foldable cardboard, etc.) is not cleaned for reuse, but is disposed of and replaced by a new unit.

Parallel disk or plate collector unit:
This subclass is indented under subclass 84. Apparatus in which individual means for attracting or gathering ionized particles are of flat or planar configuration and have comparatively large surface area, and in which each such means is held parallel to the others.
(1) Note. The structures of this subclass are usually referred to as plate type collectors. Classified here are collectors comprising flat disk or plate members, as contrasted with spherical, tubular, or other such members having surfaces of revolution.

SEE OR SEARCH THIS CLASS, SUBCLASS:
76 and 77+, for a parallel disk or plate collector unit which comprises one field in a serially diverse field arrangement.
85 for parallel plate type disposable collector assemblies.
87 for parallel disk or plate type collector arrangements not qualifying as unitized assemblies.

Parallel disk or plate collector:
This subclass is indented under subclass 83. Apparatus in which individual means for attracting or gathering ionized particles are of flat or planar configuration and have comparatively large surface area, and in which each such means is held parallel to the others.

SEE OR SEARCH THIS CLASS, SUBCLASS:
86 for parallel disk or plate collectors retained as a unitary assembly.

With insulation feature:
This subclass is indented under subclass 83. Apparatus in which the electrode retaining or supporting arrangement has electrical nonconductor means.
(1) Note. A mere housing or the like to keep parts dry is not considered a nonconductor means for this class.

SEE OR SEARCH THIS CLASS, SUBCLASS:
15 for nonconducting features other than a mere conductor sheath to maintain an electrically insulated condition.

SEE OR SEARCH CLASS:
174, Electricity: Conductors and Insulators, particularly 137 for insulators, per se, and for electrical apparatus with insulating means not limited to or solely disclosed for use in gas separators (e.g., electric field separation apparatus, etc.).

Tensioning means:
This subclass is indented under subclass 83. Apparatus in which means are provided for maintaining an electrode under tension, with the tension being due to more than the weight of the electrode.

Spring or expansible bellows:
This subclass is indented under subclass 89. Apparatus in which the tension is maintained by the use of spring means or bellows which may be expanded by stretching, with the spring means or bellows connected to the electrode in such a way as to maintain tension therein.

Hanging weight:
This subclass is indented under subclass 89. Apparatus in which the tension is provided by a hanging weight.

Suspensory means:
This subclass is indented under subclass 83. Apparatus in which the sustaining means is such as to afford support by making contact above the bottommost surface or face of the electrode in its normal operating position (e.g., electrode is held at the top, middle, etc.).

Nonrigid support (e.g., hanging electrode, etc.):
This subclass is indented under subclass 92. Apparatus in which the electrode is supported in such a way as to allow swinging movement about the point of support.
(1) Note. The provision of nonrigid damping means to reduce electrode movement during use does not exclude placement in this subclass.

Movably supported during use or for orientation:
This subclass is indented under subclass 83. Apparatus in which electrode means is sustained against gravity in such a manner as to afford movement thereof (a) while it is operative as an electrode or (b) for adjustment or orientation without disassembly.

SEE OR SEARCH THIS CLASS, SUBCLASS:
39 for movably mounted electrode assemblies so mounted for cleaning.

SEE OR SEARCH CLASS:
95, Gas Separation: Processes, subclass 77 for electric field separation processes involving a continuously moving electrode.

Ionizing electrode details (e.g., coil, mat, corona suppression, etc.):
This subclass is indented under subclass 15. Apparatus in which an ionizing electrode stock material or composite has been specially altered, configured, or constructed (e.g., coil, mat, corona suppression, etc.).
(1) Note. Although the vast majority of patents in this section of the class must include discharge electrodes, not all patents will be referred to this group. Ionizers claimed by name only and having no unusual property will be omitted from this group.
(2) Note. Electrodes having means (a) tending to limit the building up of a concentrated charge or (b) preventing the formation of a shortened discharge path, to thereby preclude
sparkover are included.

SEE OR SEARCH CLASS:
252, Compositions, 500 for comp