STATEMENT OF CLASS SUBJECT MATTER
This is the primary class for patents directed to treating water or waste liquid, and when not more specifically provided for, the class for patents directed to treating liquids in general or of any kind and provides (1) process and apparatus for (a) separating a component from (b) purifying or (c) effecting a change in water or waste liquid, such process or apparatus not being more specifically provided for in another class; (2) process of treating liquids in general and treating liquid compositions of either general or diverse utilities; (3) apparatus not provided for in other classes, for performing the foregoing processes and treating liquids of any kind; (4) filter materials or compositions peculiar to the above-mentioned processes; and (5) Processes for purification of liquids containing hazardous or toxic waste to produce a nonhazardous or nontoxic product.

LINES WITH OTHER CLASSES AND WITHIN THIS CLASS
A. GENERAL GUIDELINESS
1. Placement of Patents
a. A claim directed to the production, regeneration, or purification of a particular compound or composition (including) solutions in water is classified with the particular compound or composition. The classes providing for these compounds or compositions are set out in section III, B, 2.
A claim directed to purification or separation of water or of liquids in general with disclosure of several species each differently classifiable is classified in this class (210).
b. In classifying a claim to a combined process in which a liquid (e.g., sewage, etc.) is treated, and a useful by-product, energy or treatment is also recovered or achieved, placement is in Class 210 where the primary purpose is liquid treatment and the by-product, energy or other treatment is incidental. Placement is in the other pertinent class if the liquid treatment is incidental to the other process. If it cannot be determined which is the primary purpose of the combined process, placement is in the appropriate chemical class(es) when a chemical by-product is recovered and in this class (210) in all other instances.
Since the identical combined process may be placed as an original in either of two classes, based on intent of the inventor, a cross-reference copy should be placed in the other class involved.
See section II, A, 2 infra, for exceptions to the general rule here stated.
2.. Specific Exceptions.
a. Class 95, Gas Separation: Processes, will take a process including a liquid separation step in a Class 95 operation (e.g., regenerating a scrubbing liquid in a gas scrubbing operation, etc.).
b. A purely physical separation, e.g., filtering, specifically directed to mineral oil, is classified in this class (210), subclasses 767+.
c. A claim to a process of drying a flowable slurry or mass by physical separation, e.g., centrifuging without a step or means of contacting with a gas, is in this class (210) rather than Class 34. See line note to Class 210 in (3) Note to Class 34 definition.
d. Some classes which provide for compositions which may be used in a Class 210 process may also take a claim to a mere use of such composition. These classes include 424 and 521 and the line notes in section II, C set out the conditions which govern placement of patents in these circumstances.
e. The rehabilitation or regeneration of a filter medium, in situ is classified in this class (210), subclasses 791+, rather than in Class 134, Cleaning and Liquid Contact With Solids.
f. Separating liquids by direct application of electrolysis or electric force to the liquid, alone or combined with a step provided for in subclasses 767-808 of this class, is classified in Class 205, Electrolysis: Processes, Compositions Used Therein, and Methods of Preparing the Compositions, when electrolysis is involved, or in Class 204, Chemistry: Electrical and Wave Energy, when other electrical force as provided for in the Class 204 definition is involved.
B. CLASSES PROVIDING FOR RELATED SUBJECT MATTER.
1. Classes Providing A Specific Unit Operation Treatment Of Liquids.
References to Other Classes, below, contains classes pertaining to the following specific unit operation treatment of liquids.
Analyzing:
Burning;
Chlorinating;
Condensing;
Crystal Forming, Single;
Crystallization;
Degassing;
Disinfecting;
Dispensing;
Distilling;
Drinking Storage;
Electrolysis;
Emulsifying;
Evaporating;
Fluoridating;
Freezing;
Handling;
Heating;
Magnetizing;
Mixing;
Preserving;
Refrigerating;
Separating, Centrifugally;
Softening;
Sprinkling, Spraying, Diffusing;
Sterilizing;
Storage;
Testing;
Transporting;
2. Classes Providing Treatment Of A Specific Liquid.
References to Other Classes, below, contains classes pertaining to the following treatment of a specific liquid.
Beverage;
Black Liquor;
Cleaning Fluid;
Colloids;
Coolant;
Culture Broth;
Detergent;
Drug;
Dye;
Electrolyte;
Emulsion;
Fats;
Fertilizer;
Food;
Fuel;
Ink;
Inorganic;
Lubricants;
Medicine;
Oil;
Paints;
Photos:graphic;
3. Classes Having Liquid Treating Apparatus.
References to Other Classes, below, contains classes having liquid treating apparatus in the following art areas.
Analysis;
Carbureting;
Cooling;
Crystal Forming, Single;
Crystallizer;
Dispensing;
Distilling;
Evaporating;
Gas Contact;
Handling;
Heat Exchange;
Mixing;
Oil Refining;
Packing;
Preserving;
Reaction (Chemical);
Reaction, Physical;

REFERENCES TO OTHER CLASSES

SEE OR SEARCH CLASS:
8, Bleaching and Dyeing; Fluid Treatment Chemical Modification of Textiles and Fibers, appropriate subclasses for a purification process claimed or solely disclosed for a dye composition.
8, Bleaching and Dyeing; Fluid Treatment and Chemical Modification of Textiles and Fibers. (Class Providing Treatment Of A Specific Liquid--Dye)
15, Brushing, Scrubbing, and General Cleaning, appropriate subclasses for apparatus which may remove a liquid from a solid by means provided for in that class (15), particularly subclass 1.7 for submerged cleaners; and subclass 246.5 for tank cleaners.
19, Textiles: Fiber Preparation, appropriate subclasses which may involve the manufacture of a filter element, particularly 144 for the bringing together of fibers with relation to each other to form a coherent mass.
23, Chemistry: Physical Processes, 293 for a physical purification process claimed or solely disclosed for an inorganic compound or nonmetallic element (or solution with no art use).
23, Chemistry: Physical Processes, 230. (Class Providing A Specific Unit Operation Treatment Of Liquids--Testing)
34, Drying and Gas or Vapor Contact With Solids, appropriate subclasses. See the note to the class definition of Class 34 for the line with Class 210.
44, Fuel and Related Compositions, especially 300 for a purification process claimed or solely disclosed for liquid fuel.
44, Fuel and Related Compositions. (Class Providing Treatment Of A Specific Liquid--Oil)
44, Fuel and Related Compositions. (Class Providing Treatment Of A Specific Liquid--Fuel)
51, Abrasive Tool Making Process, Material, or Composition, for a purification process claimed or solely disclosed for an abrading composition.
53, Package Making. (Class Having Liquid Treating Apparatus--Packing)
53, Package Making. (Class Providing A Specific Unit Operation Treatment Of Liquids--Preserving)
53, Package Making. (Class Providing A Specific Unit
Operation Treatment Of Liquids--Storage)
62, Refrigeration. (Class Providing A Specific Unit Operation Treatment Of Liquids--Condensign)
62, Refrigeration, 600 for a separating or purification process for liquified gas.
62, Refrigeration, 66 and 532+. (Class Providing A Specific Unit Operation Treatment Of Liquids--Crystallization)
62, Refrigeration, especially 56. (Class Providing A Specific Unit Operation Treatment Of Liquids--Freezing)
62, Refrigeration. (Class Providing A Specific Unit Operation Treatment Of Liquids--Refrigerating)
62, Refrigeration. (Class Having Liquid Treating Apparatus--Cooling)
68, Textiles: Fluid Treating Apparatus, subclass 1 and 18 for means to reclaim and revise a solvent combined with a laundry machine.
71, Chemistry: Fertilizers. (Class Providing Treatment Of A Specific Liquid--Fertilizer)
71, Chemistry: Fertilizers, appropriate subclasses for fertilizer producing processes including more than mere treatment of sewage or waste liquids for this class (210); and for a purification process claimed or solely disclosed for a fertilizer composition.
73, Measuring and Testing, especially 32, 53+, 149, 170.29+, 861+, 290+, Dig. 5+, and Dig. 8. (Class Providing A Specific Unit Operation Treatment Of Liquids--Testing)
75, Specialized Metallurgical Processes, Compositions for Use Therein, Consolidated Metal Powder Compositions, and Loose Metal Particulate Mixtures, appropriate subclasses for a separating or purification process that produces a metal; and especially subclass 2 for beneficiating ores by chemical treatment and flotation; and subclasses 97+ for hydrometallurgical processes, particularly subclasses 101+ for chemical leaching.
95, Gas Separation: Processes, for processes involving steps resulting in separation of a gas from a fluid mixture comprising (a) a gas and solid or liquid particles entrained therein, (b) a liquid and gas entrained therein, or (c) a plurality of gases. Class 210 is superior to Class 95 and takes separating processes, per se, generically disclosed or claimed as fluid separation or if the disclosure or a claim is restricted to liquid separation. Class 210 also takes processes which remove or vent gas formed incidentally to the handling of the fluid mixture or as a result of a Class 210 treatment (see particularly subclass 603, 640, 664, 718, and
750). However, Class 95 takes processes operating to remove gas initially present in an inflowing liquid mixture, with or without liquid separation. 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 degasification of a liquid for Class 95 when the volatile organic compound is initially present as a liquid mixed with another liquid. The removal of a volatile organic compound from a liquid may be found in Class 210 for liquid purification or separation or Class 203 for separatory distillation processes. Class 95 will also take a process including a liquid separation step in a Class 95 operation (e.g., regenerating a scrubbing liquid in a gas scrubbing operation).
95, Gas Separation: Processes, especially 241. (Class Providing A Specific Unit Operation Treatment Of Liquids--Degassing)
96, Gas Separation: Apparatus, especially 155. (Class Providing A Specific Unit Operation Treatment Of Liquids--Degassing)
96, Gas Separation: Apparatus, for apparatus used in separation of a gas from a fluid mixture comprising (a) a gas and solid or liquid particles entrained therein, (b) a liquid and gas entrained therein, or (c) a plurality of gases. 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.).
99, Foods and Beverages: Apparatus, appropriate subclasses for apparatus of the type classified in this class (210) when combined with other food or beverage preparation means; and 457 and 495+ for separation apparatus wherein a liquid is separated.
100, Presses, subclass 37 for process of separation of
liquid from expressed material; and subclasses 104+ for presses having drain means for expressed liquids, and see the reference to Class 210 in the class definition for the general line.
106, Compositions: Coating or Plastic, appropriate subclasses for a purification or regeneration by separation process which is claimed or solely disclosed for a composition or ingredient of that class.
106, Compositions: Coating or Plastic, 31.13. (Class Providing Treatment Of A Specific Liquid--Ink)
106, Compositions: Coating or Plastic. (Class Providing Treatment Of A Specific Liquid--Paints
110, Furnaces. (Class Providing A Specific Unit Operation Treatment Of Liquids--Burning)
117, Single-Crystal, Oriented-Crystal, and Epitaxy Growth Processes; Non-Coating Apparatus Therefor. (Class Having Liquid Treating Apparatus--Crystal Forming, Single)
117, Single-Crystal, Oriented-Crystal, and Epitaxy Growth Processes; Non-Coating Apparatus Therefor. (Class Providing A Specific Unit Operation Treatment Of Liquids--Single Crystal Forming)
122, Liquid Heaters and Vaporizers, appropriate subclasses for conversion of liquid to vapor by application of heat.
122, Liquid Heaters and Vaporizers. (Class Providing A Specific Unit Operation Treatment Of Liquids--Heating)
126, Stoves and Furnaces, subclasses 344-363.1 for a liquid heater that may include a kettle, a steam generator, stove pipe for use with a stove, a domestic water heater or boiler (e.g., kitchen boiler, range boiler, etc.) for use with a stove or furnace.
127, Sugar, Starch, and Carbohydrates, appropriate subclasses for processes and apparatus peculiar to the treatment of such materials.
128, Surgery, appropriate subclasses for a process of or apparatus for purifying or separating the fluid (e.g., blood) of a living animal body, combined with a claimed specifically detailed step or means of removing or returning the fluid from or to the body. A method of treating the fluid including a nominally recital step of or means for removing or returning the fluid from or to a patient will be placed in this class (210). Similarly, a process of or apparatus for purifying or separating such a fluid combined with a step of or means for monitoring a condition of the body to control the purifying or separating will be placed in Class 128, Surgery. Terms as "withdrawing", "injecting", and "needle", are considered nominal while withdrawing from a named artery
or vein or structurally defining a needle are considered specific detail.
134, Cleaning and Liquid Contact With Solids, and see Note (4) of the definition of that class for the line with Class 210.
137, Fluid Handling. (Class Having Liquid Treating Apparatus--Handling)
137, Fluid Handling, appropriate subclasses for fluid handling generally, particularly 1 for processes; and subclasses 98+ for proportional flow systems, as chemical feeders.
137, Fluid Handling, 1. (Class Providing A Specific Unit Operation Treatment Of Liquids--Transporting)
137, Fluid Handling, 1. (Class Providing A Specific Unit Operation Treatment Of Liquids--Handling)
141, Fluent Material Handling, With Receiver or Receiver Coacting Means. (Class Providing A Specific Unit Operation Treatment Of Liquids--Dispensing)
141, Fluent Material Handling, With Receiver or Receiver Coacting Means. (Class Providing A Specific Unit Operation Treatment Of Liquids--Handling)
141, Fluent Material Handling, With Receiver or Receiver Coacting Means. (Class Having Liquid Treating Apparatus--Dispensing)
159, Concentrating Evaporators, 47.1 (Class Providing A Specific Unit Operation Treatment Of Liquids--Evaporating)
159, Concentrating Evaporators. (Class Having Liquid Treating Apparatus--Evaporating)
162, Paper Making and Fiber Liberation. (Class Providing Treatment Of A Specific Liquid--Black Liquor)
162, Paper Making and Fiber Liberation, appropriate subclasses for processes and apparatus for making paper by depositing fibers from a slurry on a foraminous screen. Where the screening step is for the purpose of dewatering the slurry and a formless mass of fibers is produced rather than a felted product, the patent is classified in Class 210. Where there is a disclosure of a felted self-sustaining product being produced by the dewatering step or means are provided to remove the product intact from the mold, the patent is classified in Class 162.
165, Heat Exchange. (Class Having Liquid Treating Apparatus--
165, Heat Exchange. (Class Providing A Specific Unit
Operation Treatment Of Liquids--Refrigerating)
165, Heat Exchange. (Class Providing A Specific Unit Operation Treatment Of Liquids--Condensign)
165, Heat Exchange. (Class Providing A Specific Unit Operation Treatment Of Liquids--Heating)
165, Heat Exchange. (Class Having Liquid Treating Apparatus--Cooling)
166, Wells, 265 for well processes involving separation of fluids leaving the well, appropriate subclasses for corresponding well apparatus; subclasses 311+ and subclasses there noted for processes of cleaning wells, and appropriate subclasses for corresponding apparatus; subclasses 227+ and subclasses there noted for well screens; and see subclass 227 for the line between Classes 210 and 166 as to screens.
196, Mineral Oils: Apparatus. (Class Having Liquid Treating Apparatus--Oil Refining)
196, Mineral Oils: Apparatus, for apparatus peculiar to mineral oil treatment other than by mere manipulative treatment for this class (210), particularly subclass 14.5 for dewaxing apparatus; and subclass 46.1 for refining apparatus including a filter in combination.
202, Distillation: Apparatus, appropriate subclasses for distillation apparatus with or without separation means of the type classified in Class 210.
202, Distillation: Apparatus. (Class Having Liquid Treating Apparatus--Distilling)
203, Distillation: Processes, Separatory, 28 and 39+ for a liquid distillation process including a chemical treating step or a disparate physical separating step not otherwise provided for.
203, Distillation: Processes, Separatory. (Class Providing A Specific Unit Operation Treatment Of Liquids--Distlling)
204, Chemistry: Electrical and Wave Energy, for the separation or purification of a liquid solely by the application of an electrical force directly to the liquid or when combined with a separation step classifiable in Class 210, subclasses 767-808. Exemplary is electro-osmosis with or without filtration or electrophoresis with or without gravitational setting. A Class 204 step combined with a Class 210 process provided for higher in the Class 210 schedule than subclasses 767-808 is classifiable in Class 210. Such combinations are exemplified by sorption plus electro-osmosis, precipitation plus electrophoresis, etc. Class 204 also takes a combined process which may include a preparatory liquid purification step for the process. See the reference to Class 210 in the Class 204 definition,
References to Other Classes section for an elaboration of the class line between Class 204 and Class 210.
205, Electrolysis: Processes, Compositions Used Therein, and Methods of Preparing the Compositions, appropriate subclasses for an electrolytic process which may include a preparatory liquid purification step for the process, for a composition intended for use in such a process (e.g., electrolyte, etc.), for a process of regenerating or rehabilitating an electrolyte composition used or intended to be used for electrolysis as designated for Class 205, and subclasses 775-794.5 for electrolytic analysis or testing. A Class 205 step combined with a Class 210 process provided for higher in the schedule than subclasses 767-808 is classifiable in Class 210. Such combinations are exemplified by aerobic digestion plus electrolysis, etc. Class 205 also takes an electrolytic process which may include a preparatory liquid purification step for the process.
205, Electrolysis: Processes, Compositions Used Therein, and Methods of Preparing the Compositions, appropriate subclasses for a process involving electrolysis and for a composition intended for use in such a process (e.g., electrolyte, etc.). See section III of the Class 204 definition for an elaboration of the class line between Class 204 (which encompasses Class 205) and Class 210. (Class Providing Treatment Of A Specific Liquid)
205, Electrolysis: Processes, Compositions Used Therein, and Methods of Preparing the Compositions, appropriate subclasses for a process involving electrolysis. See section III of the Class 204 definition for an elaboration of the class line between Class 204 (which encompasses Class 205) and Class 210. (Class Providing A Specific Unit Operation Treatment Of Liquids--Electrolysis)
205, Electrolysis: Processes, Compositions Used Therein, and Methods of Preparing the Compositions, appropriate subclasses for a process involving electrolysis, especially 775 for electrolytic analysis or testing. See section III of the Class 204 definition for an elaboration of the class line between Class 204 (which encompasses Class 205) and Class 210. (Class Providing A Specific Unit Operation Treatment Of Liquids--Testing)
208, Mineral Oils: Processes and Products, for a purification or separation claimed as solely disclosed for mineral oil and which is not purely a physical operation as provided for in 767 of this class (210). Class 210, in subclasses 767+ provides for merely physically separating a mineral oil as by filtering, settling decanting, etc. Class 208 provides for chemical, including sorption and solvent, processes for purifying or separating a mineral oil.
208, Mineral Oils: Processes and Products. (Class Providing Treatment Of A Specific Liquid--Lubricants)
208, Mineral Oils: Processes and Products. (Class Providing Treatment Of A Specific Liquid--Oil)
208, Mineral Oils: Processes and Products. (Class Providing Treatment Of A Specific Liquid--Fuel)
209, Classifying, Separating, and Assorting Solids, appropriate subclasses, and see the reference to Class 210 under (3) Note of the class definition of Class 209 for the general line.
219, Electric Heating. (Class Providing A Specific Unit Operation Treatment Of Liquids--Heating)
222, Dispensing. (Class Providing A Specific Unit Operation Treatment Of Liquids--Dispensing)
222, Dispensing. (Class Having Liquid Treating Apparatus--Dispensing)
239, Fluid Sprinkling, Spraying, and Diffusing, appropriate subclasses for separating means incidental or ancillary to handling a fluid to be sprinkled or sprayed, especially subclass 86, 462, 553+, 575, and 590+ for nozzle structures in which filtering means are present or are inherent in the nozzle.
239, Fluid Sprinkling, Spraying, and Diffusing. (Class Providing A Specific Unit Operation Treatment Of Liquids--Handling)
239, Fluid Sprinkling, Spraying, and Diffusing, 1. (Class Providing A Specific Unit Operation Treatment Of Liquids--Sprinkling, Spraying, Diffusing)
241, Solid Material Comminution or Disintegration, subclass 24 and 68+ for the comminution of solids combined with the separation of liquid therefrom. See section 8 of the class definition of Class 241 for the line with Class 210.
250, Radiant Energy. (Class Providing A Specific Unit Operation Treatment Of Liquids--Sterilizing)
250, Radiant Energy, 527 .. (Class Having Liquid Treating Apparatus--Reaction (Chemical))
252, Compositions, 175. (Class Providing A Specific Unit Operation Treatment Of Liquids--Softening)
252, Compositions, 380. (Class Providing A Specific Unit Operation Treatment Of Liquids--Preserving)
252, Compositions, appropriate subclasses for a purification or separation claimed or solely disclosed for a composition classifiable in that class, and search subclass 61 and 175+ for a composition which may be used in a liquid purification or separation process of this class. Class 252 provides for
a purification or separation process specific to a single type of composition by claim or by sole disclosure. Class 210 provides for a purification or separation process generic to several types of compositions, all of which may be classified in Class 252 (e.g., perfumes and denaturants; detergents; fire extinguishing and heat exchange materials). Class 252 provides for certain compositions for use in Class 210 processes and for a process, per se, of regenerating or rehabilitating them. The use of these compositions in a liquid purification or separation, per se, or combined with regenerating them is provided for in Class 210.
252, Compositions, 71. (Class Providing Treatment Of A Specific Liquid--Coolant)
252, Compositions, various subclasses based on function of emulsion. (Class Providing A Specific Unit Operation Treatment Of Liquids--Emulsifying)
260, Chemistry of Carbon Compounds, appropriate subclasses for such compounds and related compound producing or treating processes, particularly 704 for general physical treatment processes peculiar to carbon compounds, and see the references to Class 210 in the class definition.
261, Gas and Liquid Contact Apparatus, 2 for separating means combined with apparatus to produce an intimate contact between gases and liquids to exchange properties or mutually modify conditions.
261, Gas and Liquid Contact Apparatus. (Class Having Liquid Treating Apparatus--Gas Contact)
261, Gas and Liquid Contact Apparatus. (Class Having Liquid Treating Apparatus--Carbureting)
264, Plastic and Nonmetallic Article Shaping or Treating: Processes, appropriate subclasses for processes for shaping or molding plastic materials within the class definition, which may involve the manufacture or use of fiber elements or separators, or porous articles, per se.
324, Electricity: Measuring and Testing, especially 29, 71+, 204, 425+, and 459+. (Class Providing A Specific Unit Operation Treatment Of Liquids--Testing)
335, Electricity: Magnetically Operated Switches, Magnets, and Electromagnets. (Class Providing A Specific Unit Operation Treatment Of Liquids--Magnetizing)
361, Electricity: Electrical Systems and Devices. (Class Providing A Specific Unit Operation Treatment Of Liquids--Magnetizing)
366, Agitating. (Class Having Liquid Treating Apparatus--Mixing)
366, Agitating, 2 and 348. (Class Providing A Specific Unit Operation Treatment Of Liquids--Mixing)
399, Electrophotography, subclass 250 for liquid carrier condensation of liquid developer material within an electrophotos:graphic device.
406, Conveyors: Fluid Current, especially 168 and 197 for transporting a solid by suspending it in a fluid and separating the solid from the liquid after transporting.
406, Conveyors: Fluent Current. (Class Providing A Specific Unit Operation Treatment Of Liquids--Transporting)
422, Chemical Apparatus and Process Disinfecting, Deodorizing, Preserving, or Sterilizing, for a process of treating water to prevent corrosion of a conduit or a container and for chemical apparatus of general utility.
422, Chemical Apparatus and Process Disinfecting, Deodorizing, Preserving, or Sterilizing, 243 .. (Class Having Liquid Treating Apparatus--Reaction, Physical)
422, Chemical Apparatus and Process Disinfecting, Deodorizing, Preserving, or Sterilizing. (Class Having Liquid Treating Apparatus--Preserving)
422, Chemical Apparatus and Process Disinfecting, Deodorizing, Preserving, or Sterilizing, 129 .. (Class Having Liquid Treating Apparatus--Reaction (Chemical))
422, Chemical Apparatus and Process Disinfecting, Deodorizing, Preserving, or Sterilizing, 245.1 for non-coating means not including means for chemical reaction and not provided for elsewhere. (Class Having Liquid Treating Apparatus--Crystallizer
422, Chemical Apparatus and Process Disinfecting, Deodorizing, Preserving, or Sterilizing, subclass 13 and 14+. (Class Providing A Specific Unit Operation Treatment Of Liquids--Softening)
422, Chemical Apparatus and Process Disinfecting, Deodorizing, Preserving, or Sterilizing, 1. (Class Providing A Specific Unit Operation Treatment Of Liquids--Preserving)
422, Chemical Apparatus and Process Disinfecting, Deodorizing, Preserving, or Sterilizing. (Class Providing A Specific Unit Operation Treatment Of Liquids--Storage)
422, Chemical Apparatus and Process Disinfecting, Deodorizing, Preserving, or Sterilizing, subclasses 1-43. (Class Providing A Specific Unit Operation Treatment Of Liquids--Disinfecting)
422, Chemical Apparatus and Process Disinfecting, Deodorizing, Preserving, or Sterilizing, 1. (Class Providing
A Specific Unit Operation Treatment Of Liquids--Sterilizing)
422, Chemical Apparatus and Process Disinfecting, Deodorizing, Preserving, or Sterilizing, 50. (Class Having Liquid Treating Apparatus--Analysis)
423, Chemistry of Inorganic Compounds, appropriate subclasses for chemical manufacturing involving a chemical reaction and for extracting, leaching, or dissolving not elsewhere provided for.
423, Chemistry of Inorganic Compounds. (Class Providing Treatment Of A Specific Liquid--Inorganic)
424, Drug, Bio-Affecting and Body Treating Compositions. (Class Providing Treatment Of A Specific Liquid--Drug)
426, Food or Edible Material: Processes, Compositions, and Products. (Class Providing A Specific Unit Operation Treatment Of Liquids--Preserving)
424, Drug, Bio-Affecting and Body Treating Compositions. (Class Providing A Specific Unit Operation Treatment Of Liquids--Disinfecting)
424, Drug, Bio-Affecting and Body Treating Compositions, especially 661. (Class Providing A Specific Unit Operation Treatment Of Liquids--Chlorinating)
424, Drug, Bio-Affecting and Body Treating Compositions, 56. (Class Providing A Specific Unit Operation Treatment Of Liquids--Fluoridating)
424, and 514, Drug, Bio-Affecting and Body Treating Compositions, especially Class 424, 127 and Class 514, subclasses 1+. (Class Providing A Specific Unit Operation Treatment Of Liquids--Sterilizing)
424, Drug, Bio-Affecting and Body Treating Compositions. (Class Providing Treatment Of A Specific Liquid--Medicine)
426, Food or Edible Material Processes, Compositions, and Products. (Class Providing Treatment Of A Specific Liquid--Beverage)
426, Food or Edible Material: Processes, Compositions, and Products. (Class Providing A Specific Unit Operation Treatment Of Liquids--Storage)
426, Food or Edible Material: Processes, Compositions, and Products, appropriate subclasses for (a) process of the type classified in this class (210) when combined with other food working operations, or (b) a process of the type classified in this class (210), which process is limited to treatment of a food or edible material except water.
426, Food or Edible Material: Processes, Compositions, and
Products. (Class Providing Treatment Of A Specific Liquid--Food)
426, Food or Edible Material: Processes, Compositions, and Products, 66. (Class Providing A Specific Unit Operation Treatment Of Liquids--Drinkign Storage)
429, Chemistry: Electrical Current Producing Apparatus, Product and Process, especially 30, 101+, and 188+. (Class Providing Treatment Of A Specific Liquid)
430, Radiation Imagery Chemistry: Process, Composition, or Product Thereof. (Class Providing Treatment Of A Specific Liquid--Emulsion)
430, Radiation Imagery Chemistry: Process, Composition, or Product Thereof. (Class Providing Treatment Of A Specific Liquid--Photos:graphic)
431, Combustion. (Class Providing A Specific Unit Operation Treatment Of Liquids--Burning)
432, Heating. (Class Providing A Specific Unit Operation Treatment Of Liquids--Heating)
435, Chemistry: Molecular Biology and Microbiology. (Class Providing Treatment Of A Specific Liquid--Culture Broth)
436, Chemistry: Analytical and Immunological Testing, 1 and 129.2+. (Classes Providing A Specific Unit Operation Treatment Of Liquids--Analyzing)
494, Imperforate Bowl: Centrifugal Separators, appropriate subclasses, for apparatus and process for breaking up a mixture of fluids or fluent substances into two or more components by centrifuging within a generally solid-walled, receptacle-like member.
494, Imperforate Bowl: Centrifugal Separators. (Class Providing A Specific Unit Operation Treatment Of Liquids--Centrifugally separating)
502, Catalyst, Solid Sorbent, or Support Therefor: Product or Process of Making, for a composition comprising a catalyst or sorbent, per se.
504, Plant Protecting and Regulating Compositions, 150 for compositions designed or intended for retarding, inhibiting, or killing algae and the processes of using such compositions or compounds which are no more than the mere application of the compounds or the compositions.
508, Solid Antifriction Devices, Materials Therefor, Lubricants or Separants for Moving Solid Surfaces, and Miscellaneous Mineral Oil Compositions, particularly 110. (Class Providing Treatment Of A Specific Liquid--Lubricants)
508, Solid Antifriction Devices, Materials Therefor, Lubricants or Separants for Moving Solid Surfaces, and Miscellaneous Mineral Oil Compositions, particularly 110. (Class Providing Treatment Of A Specific Liquid--Oil)
510, Cleaning Compositions for Solid Surfaces, Auxiliary Compositions Therefor, or Processes of Preparing the Compositions. (Class Providing Treatment Of A Specific Liquid Detergent)
510, Cleaning Compositions for Solid Surfaces, Auxiliary Compositions Therefor, or Processes of Preparing the Compositions, appropriate subclasses, especially 285, 405+, etc. (Class Providing Treatment Of A Specific Liquid--Cleaning Fluid)
514, Drug, Bio-Affecting and Body Treating Compositions, especially 939. (Class Providing Treatment Of A Specific Liquid--Emulsion)
516, Colloid Systems and Wetting Agents; Subcombinations Thereof; Processes of Making, Stabilizing, Breaking, or Inhibiting, appropriate subclasses for subject matter relating to: colloid systems (such as sols*, emulsions, dispersions, foams, aerosols, smokes, gels, or pastes) or wetting agents (such as leveling, penetrating, or spreading); subcombination compositions of colloid systems containing at least an agent specialized and designed for or peculiar to use in making or stabilizing colloid systems; compositions and subcombination compositions specialized and designed for or peculiar to use in breaking (resolving) or inhibiting colloid systems; processes of making the compositions or systems of the class; processes of breaking (resolving) or inhibiting colloid systems; in each instance, when generically claimed or when there is no hierarchically superior provision in the USPC for the specifically claimed art. Class 516 is the locus for the breaking of colloid systems generically claimed and provides for (a) the separation or purification of liquids, generally claimed, when performed by a Class 516 process, such as by breaking an emulsion, dispersion, or foam, and for such processes further including ancillary steps, such as, decanting, or passing through a separatory funnel, etc., or (b) processes in which recovery is intended of both water and another product. Class 210 provides for (a) processes which include a step of colloid system resolution of liquids, generally claimed, when combined with a step of separation of a diverse component, unless that step is also a Class 516 step (i.e., multiple Class 516 steps are proper for placement in Class 516), or (b) a step of colloid system breaking, per se, for the purpose of obtaining water, wherein the water may be intended for use or intended to be made suitable for disposal, thus, decontaminating of sewage waste water to be dumped into the ocean using an emulsion breaking step is proper for Class 210. (Class Providing A Specific Unit Operation Treatment Of Liquids--Emulsifying) (Class Providing Treatment Of A Specific Liquid Colloids) (Class Providing Treatment Of A
Specific Liquid Emulsion)
520, Series, Synthetic Resins or Natural Rubbers. (Class Providing Treatment Of A Specific Liquid--Paints)
520, Synthetic Resins or Natural Rubbers, particularly Classes 523 and 524. (Class Providing Treatment Of A Specific Liquid--Emulsion)
554, Organic Compounds, 1. (Class Providing Treatment Of A Specific Liquid--Fats)
585, Chemistry of Hydrocarbon Compounds, subclass 14. (Class Providing Treatment Of A Specific Liquid--Fuel)
588, Hazardous or Toxic Waste Destruction or Containment, appropriate subclasses for separation prior to destruction wherein no desired product is removed.

GLOSSARY:
The meaning to be given various "Art" terms appearing in this class, but which have not been included in the GLOSSARY below, is the same as that generally accepted or in common usage.
ABSORB
See SORB.
ACCELERATOR
Agent which promotes an action, but does not necessarily cause the action. An example is a catalyst as contrasted with a reactant. In subclasses 696+ and 702+ no distinction is made between an agent which promotes or one which causes and a search for a compound used as a flocculant is the same as if the compound reacted to cause precipitation.
ACTIVATED SLUDGE
Common term for an aerobic process of treating sewage with micro-organisms in which part of the settled sludge from the treatment is diverted and introduced into the feed of incoming sewage.
ADDITIVE
An agent added to a liquid being treated to either cause a desired result or to promote a result which would occur more slowly or incompletely without the additive. Catalysts filter aids, chemical agents, seeding agents, buffers are all additives.
ADSORB
See SORB.
AEROBIC
Treating liquids, generally sewage, with micro-organisms in the presence of oxygen generally supplied as air or other source of oxygen but sometimes using residual dissolved oxygen. Best known method is "activated sludge". The micro-organisms convert noxious materials to less noxious stuff, e.g., to water, methane, nitrogen oxides, carbon dioxide.
ALGAECIDE
Any material capable of inhibiting or destroying algal growth.
ANAEROBIC
Treating liquids, generally sewage by micro-organisms which change noxious stuff to innocuous materials, in the absence of oxygen. Some solids are made into water and gases as methane, carbon monoxide, etc. A septic tank is an example of anaerobic digestion of sewage.
ANGSTROM
A unit of length used to measure wavelength of lights and diameters of atoms or molecules.
Designated by A and equal to 10[supscrpt]-8[end supscrpt]cm.
AQUEOUS
A liquid containing water. Generally water is the major part as in blood, brine, milk, etc., but may comprise a substantial but not major portion as in a water-alcohol mixture of various proportions. Usually trace amounts of water are not considered aqueous.
BACTERICIDE
Any material capable of inhibiting or destroying bacteria.
BRACKISH
Somewhat salty, but substantially less so than sea water.
BRINE
A relatively concentrated salt water solution sometimes from wells or industrial sources and including sea water.
CENTRIFUGE
A process or means in which a liquid is revolved about an axis at such a number of revolutions per unit of time that the apparent weight of constituents increases to a point
where the constituents tend to concentrate in strata similar to gravity-induced separation based on relative densities.
CHROMATOGRAPHY
A process in which a liquid is flowed along a linear path comprising a sorbent, with which the liquid competes in affinity for a constituent of the liquid. The constituent is sorbed from the moving liquid by the relatively immobile sorbent and redissolved by a later passing portion of the liquid until an equilibrium of the sorbing-dissolving step is set up causing the constituent to concentrate in a specific volume of the sorbent and to move along the path of the liquid at a slower rate than such liquid.
A comprehensive treatise on chromatography is to be found in Kirk-Othmer Encyclopedia of Chemical Technology 2nd ed. Vol. 5, pp. 413-450.
COALESCE
The merging together of small droplets or particles of a material or constituent dispersed in a liquid to form larger bodies of the material or constituent which may be more easily handled.
COLLOIDAL
A state of very fine division of a material dispersed throughout a liquid almost to the point of a true solution and either impossible or extremely difficult to filter or cause to settle.
CONDUCTIVITY WATER
An extremely pure water characterized by high ohmic resistance due to very low rate of ionization. See POLISHING.
CYCLONE
A device using centrifugal force to separate. The process is called cyclonic; see centrifuge.
DESALINATION
The process of removing inorganic salts, most usually sodium chloride, from water.
DIALYSATE
See DIALYSIS.
DIALYSIS
A process of separating a dissolved constituent from a liquid by transport or migration from the liquid through a membrane
into a second liquid. The membrane may be semipermeable or the second liquid may have greater affinity for the constituent but the net effect of the combined membrane-extracting liquid is to selectively remove a constituent from the first liquid. The process is provided for in subclasses 644+. An in-depth explanation is given in Kirk Othmer Encyclopedia of Chemical Technology 2nd ed. Vol. 7, pp. 1-20. Dialysate is the product of a dialysis method and the term is not always used for the same product, including retentate and diffusate.
DIFFUSATE
The material passed through in a diffusing process.
DIFFUSE
The passing of a constituent through a membrane or septum.
DIGEST
Process in which material is acted upon by micro-organisms to cause a chemical change. The composting of sludge is a digestion process.
DISPERSION
A mixture of a liquid with an insoluble material in very fine subdivision almost but not quite a true solution.
EFFLUENT
The liquids flowing out of a process, normally the mainstream, can be either a desired product or discard.
FEED
The liquid to be treated, prior to processing.
FILTER
Method of and apparatus for removing solid particles from a liquid by passing the same through a medium with openings smaller than the particles. Microfiltration is filtration down to coolidal and polymeric molecular size. Ultrafiltration and hyperfiltration are more likely transport or diffusion across a membrane process but are called filtration down to molecular and ionic size. See subclasses 650 and 652.
FILTER ELEMENT
Filter medium combined with supporting structure or having a specified shape.
FILTER MEDIUM
Solid separating material or member for separating a constituent from the prefilt due to openings between material particles or in the member.
FILTRATE
Liquid which has been clarified by passing it through a filter medium.
FILTRATION
The separation of solids from a liquid or a liquid from liquids by a solid separating medium due to openings in the medium or between discrete particles.
FLOC
Flocculated clumps of suspended or dispersed small particles resulting from accretion and used as sites for further accretion of suspended matter. See subclass 715.
FLOCCULATION
A clumping together of finely divided particles of material dispersed in a liquid to a state where filtration or settling of the material is possible. See subclasses 702+.
FLUID
Material that flows, generally gas or liquid but sometimes including mixtures of these with particulate solids such as slurry, sludge, gels, etc. Some materials are thixatropic, i.e., fluid when agitated but jellylike when at rest. Pumpable sludge is considered a liquid for treatment in this class.
FOULING
The act of depositing on the membrane surface something which will impede its proper functioning. Sometimes also termed "blinding".
GEL
A colloidal dispersion of a solid in a liquid with a jellylike texture. Use of a gel in chromatography is in subclass 635, and separating the constituents of a gel are in subclass 702.
GRAVITY, BY
A separation process depending on differences in density to separate freely movable constituents such as cream rising to the top of the milk. Draining or allowing a liquid to drip from solids held by a screen or grid is not gravity separation.
HYDROPHILIC
Water attractive or wettable.
HYDROPHOBIC
Water-repellent or nonwettable.
HYPERFILTRATION
Filtration to the ultimate degree to molecular or ionic size, but most likely membrane transport or diffusion phenomenon. See FILTER and subclass 652.
IMHOFF
A two-story septic tank of special design to allow digestion of sludge in lower chamber with settling in upper chamber and passage of settled sludge from upper to lower chamber. Process is anaerobic and provided for in subclasses 602+.
INERT MATERIAL
Stuff that does not cause or promote any change in liquid or component being treated. May act as filler, support, or carrier for active material. See subclass 679.
LIQUID
A flowable material comprising at least one component that is a true liquid under the conditions of treatment. A slurry, wet sludge, pumpable sediment, emulsion, froth, all are considered liquid for treatment in this class.
MAINSTREAM
The main body of liquid being treated as constrasted with separated constituents. The mainstream may comprise several divided streams, some of which undergo treatment and which are a substantial part of the overall feed but a relatively small stream diverted for a dosing technique in which agents are added in a concentrated amount and the diverted stream is diluted with the main body is not considered to be the mainstream, per se. A recirculated portion of the stream is not considered to be the mainstream.
MEMBRANE
A skinlike thin film which acts as a barrier or container wall; the usual form of a permeable or semipermeable septum. A semipermeable membrane is a skinlike, relatively thin film which serves to define a barrier or container wall to at least one of the constituents of a solution or colloidal suspension and allows at least one other constituent to pass through by a mechanism which may include but goes beyond mere straining and which mechanism is in part due to differences in behavior of the constituents of the solution or suspension
with respect to the material of the membrane. The constituents vary in their ability to diffuse through or to wet the membrane.
Membranelike includes mambrane, per se, and material which, while not strictly in a self-supporting skinlike structure, functions in an analogous manner and includes a layer of fine particulate matter or an emulsion as set out in subclass 643.
A process which depends only on the relative size of pores and molecules or ions of a constituent is a filtering or straining process and is classified under separation, subclass 767.
MICRON
A linear measurement equal to one millionth of a meter, one thousandth of a mm, 39 millionths of an inch.
MICRO-ORGANISM
Living plants or animals of a size normally visible only through a microscope and includes bacteria, yeast, fungi, and virus. For purposes of this class, algae are not considered micro-organisms. The scope of this term is coextensive with the organisms of Class 435, Molecular Biology and Microbiology.
MICROFILTER
See FILTER.
MOLECULAR SIEVE
A sorbent with an extremely large volume of pores, each of about molecular size, capable of selectively sorbing gases and other material in molecular form; generally of Zeolite.
OIL
Organic material of slick or slippery feel including long chain hydrocarbons esters of higher fatty acid and derived from petroleum, fats, greases, and oils of animal or vegetable origin.
OLEOPHILIC
Oil attractive or wettable by oil.
OLEOPHOBIC
Oil repelling.
OSMOSIS
Phenomenon in which solvent migrates or is transported across
a barrier from a less concentrated solution to a more concentrated solution separated by the barrier tending to equalize the concentrations. The force driving the solvent is dependent on the materials of the liquids and the barrier or septum, and a counter force of greater magnitude will effect reverse migration or reverse osmosis causing solvent to migrate from the more concentrated to the less concentrated solution. A comprehensive treatise on osmosis and reverse osmosis is given in Kirk-Othmer Encyclopedia of Chemical Technology 2nd ed. Vol. 14, pp. 345-355.
OXIDANT
An agent which extracts electrons from a chemical moiety and increases its positive or decreases its negative valence. Often an oxygen or halogen containing material.
PERMEABLE
Property of allowing passage or migration of other material through a barrier or septum of the material so designated. The migration phenomenon is due primarily to the chemical nature of the materials involved and may include molecular weight or size as a factor.
PERMEATE
Material which has passed through a permeable or semipermeable membrane.
pH
The measure of the acidity or basicity (alkalinity) of a liquid. Also determines the sweetness or sourness of a liquid. The original value was the log of the reciprocal of the hydrogen ion concentration.
POLISHING
An ion exchange process in which the ions released to the liquid are only H[supscrpt]+[end supscrpt] and OH[supscrpt]-[end supscrpt]. A method of achieving very pure water. See CONDUCTIVITY WATER.
PREFILT
Material to be filtered, also known as feed, influent, intake.
RESIDUE
Material retained by membrane, septum, filter, settling tank, etc.
RETENTATE
Material held back by membrane or filter, not allowed to
migrate or pass through.
REVERSE OSMOSIS
See OSMOSIS.
SEMIPERMEABLE
Permeable to only some of materials which may be in intimate association as in a solution. Usually applied to membrane, see MEMBRANE.
SLUDGE
Concentrate of settled colloidal suspension with a mushy or mud texture, a gel with up to more than 90 percent usually water) but quite viscous. It may contain indiscriminate solids as grits, fiber, wood chip, and emulsions. While still wet, treatment is proper for this class, but the same material when completely dry may be referred to as sludge. See ACTIVATED SLUDGE.
SORB, SORBING
The attracting by a solid material of a liquid wherein the liquid permeates the body of the solid, either in pores or throughout the material itself or of a finely divided constituent, suspended or dissolved in a liquid, on the surface of or in pores of the material. Examples of the former are methods using sponges, mops, and pads and of the latter are methods using activated charcoal clays and zeolites. In this class, no distinction is made between absorption and adsorption. Processes using sorption for separation are provided for in subclasses 660+. (See Kirk-Othmer Encyclopedia of Chemical Technology 2nd ed. Vol. 1, pp. 44-75 and 421-469.)
SUSPENSION
Liquid carrying throughout its volume in extremely fine subdivision an insoluble substance (solid or another liquid) which will not settle under gravity nor can be filtered without special treatment such as addition of chemical agents. A DISPERSION. See FLOCCULATION, GEL, and MEMBRANE.
SYNTHETIC
A material not found in nature, but man-made from chemical building blocks, with properties resembling naturally occurring materials. It does not include man-made duplicates of natural material or chemical modified natural materials. For example, regenerated cellulose and cellulose acetate are not included nor is zein, but polyester, vinyl, and nylon are included.
TRICKLING FILTER
A particulate bed of designed coarseness through which liquid is gravity fed at a rate to maintain relatively thin films on the particles and enhance air liquid contact to promote aerobic treatment of the liquid. An alternate method may be programmed flooding and draining of the bed. The treatment using such a bed is in subclasses 616+.
ULTRAFILTRATION
Filtration of a solution or colloid, retaining a constituent of macromolecule dimension. See FILTRATION and MEMBRANE.
VAPOR
A normally liquid material in a gaseous state, e.g., steam. Separating or purifying a fluid in the gaseous state is proper for Class 55, Gas Separation, but treating a liquid with gaseous constituents is provided for in subclasses 603+, 640, 664, 707, 718, and 750.
WASTE
A liquid that is to be discarded. The term includes effluent from domestic or industrial sources, e.g, sewage wash water spent processing fluids, etc., and refers to liquid to be treated and liquid which has been treated to allow discharge to the environment.

This subclass is indented under the class definition. Apparatus with an alarm indicator, register, recorder or signal, showing a condition of the subject matter of the class; or with means which permit inspection of normally hidden parts of the apparatus or of the fluid inside the apparatus.

SEE OR SEARCH THIS CLASS, SUBCLASS:
138 for controlled devices including only the driving mechanism of a clock without any indication other than that of a conventional clock.

SEE OR SEARCH CLASS:
73, Measuring and Testing, appropriate subclasses, for pressure, level, temperature, etc., measuring and indicating means, per se, especially subclass 61.41 for methods and means for testing which determines a characteristic of a separated constituent.
116, Signals and Indicators, appropriate subclasses, for mechanical signals and indicators, per se.
118, Coating Apparatus, 712 for coating apparatus and a signal or an indicator.
222, Dispensing, 23 for dispensers with recorder, register, indicator, signal or exhibitor.
235, Registers, appropriate subclasses, for registers, per se.
340, Communications: Electrical, 603 for electrical automatic fluent material responsive indicating systems.
346, Recorders, appropriate subclasses, for recorders, per se.

This subclass is indented under subclass 85. Apparatus, responsive to a change in the level or thickness of a material being treated within the apparatus.

This subclass is indented under subclass 85. Apparatus responsive to flow of fluids.

This subclass is indented under subclass 87. Apparatus in which a meter controls an operating cycle of the apparatus.

This subclass is indented under subclass 88. Apparatus, including means operating during or after a predetermined interval of time.

This subclass is indented under subclass 85. Apparatus responsive to fluid pressure.

This subclass is indented under subclass 85. Apparatus comprising means which gives information as to the position of a movable or adjustable part of the apparatus.

This subclass is indented under subclass 85. Apparatus including a valve which may be opened for test purposes.

This subclass is indented under subclass 85. Apparatus comprising a section in a conduit downstream from treating means.

This subclass is indented under subclass 85. Apparatus in which the inspection means is a transparent part of a treating means.

SEE OR SEARCH CLASS:
222, Dispensing, 154 for dispensers with inspection devices.

This subclass is indented under subclass 94. Apparatus comprising transparent means associated with treatment apparatus through which material being treated can be viewed.

SEE OR SEARCH CLASS:
73, Measuring and Testing, 323 for liquid level sight glasses of general application.

CONSTITUENT MIXTURE VARIATION RESPONSIVE:
This subclass is indented under the class definition. Apparatus in which an operating condition of the apparatus is controlled by variations of a constituent quality of a liquid mixture as determined by physical or chemical tests of the liquid mixture.

SEE OR SEARCH THIS CLASS, SUBCLASS:
662 for composition testing in ion exchange or sorption processes.

SEE OR SEARCH CLASS:
23, Chemistry: Physical Processes, subclass 230 for analytical and analytical control methods there provided for.
137, Fluid Handling, 3 for processes of mixing plural fluids of diverse characteristics; and subclasses 88+ for a system involving mixture condition maintaining or sensing.

With membrane:
This subclass is indented under subclass 96.1. Apparatus having a filtering means composed of a thin, enveloping or lining substance, i.e., membrane.

SEE OR SEARCH THIS CLASS, SUBCLASS:
257.1 for a membrane within a storage unit in serially connected distinct treating apparatus.
348 for apparatus which uses a semipermeable septum which does not provide for continuous streams on both sides of the septum.
433 for similar apparatus which uses in ordinary filter septum.
500.1 for membrane, per se.
541 for membrane supports, frames, and spaces.
634 for process of using a septum selective as to composition.

SEE OR SEARCH CLASS:
127, Sugar, Starch, and Carbohydrates, subclass 10 for a sugar solution dialyzer.
204, Chemistry: Electrical and Wave Energy, 252 for a similar device using an electric current.
604, Surgery, subclass 6.09 for membrane separation devices used in blood treat

This subclass is indented under the class definition. Apparatus having means responsive to variations in flow, material level or fluid pressure to control means to effect an operation or change in an operating condition.

SEE OR SEARCH THIS CLASS, SUBCLASS:
156 for a fluid stream or residue operated flume stream type separator.
349 for a filter with pulsation dampening means.
354 for a filter medium or cleaner or agitator moved by fluid.

SEE OR SEARCH CLASS:
162, Paper Making and Fiber Liberation, subclass 258 for paper making apparatus having automatic control of stock consistency, and subclass 259 for automatic control of stock feed to the foraminous forming screen.
204, Chemistry: Electrical and Wave Energy, subclass 662 for an electrical or magnetic apparatus to separate or purify a liquid with a control means responsive to a sensed liquid level.

This subclass is indented under subclass 97. Apparatus in which an operating cycle is controlled in response to the liquid flow.

SEE OR SEARCH THIS CLASS, SUBCLASS:
88 for a meter controlled cyclic system.

This subclass is indented under subclass 97. Apparatus in which there is means for diverting the initial charge of prefilt to drain, said means being responsive to accumulation of prefilt in a nonseparating receiver.

SEE OR SEARCH THIS CLASS, SUBCLASS:
130 for a fluid pressure responsive bypass.
421 for a filter with a manually operated prefilt deflector.

SEE OR SEARCH CLASS:
137, Fluid Handling, subclass 120 for self-controlled branched flow systems having alternate outflows including liquid level sensing means.

This subclass is indented under subclass 97. Apparatus which causes a flow controller to close, after which a necessary resetting operation must be preformed by an external operator.

This subclass is indented under subclass 97. Apparatus including means to maintain the ratio between plural flows at a predetermined value in response to means sensing a change in fluid condition in at least one of the flow lines.

SEE OR SEARCH THIS CLASS, SUBCLASS:
105 for diverse condition responsive controls one of which controls an auxiliary liquid inlet.
127 for a separator having a float controlled auxiliary fluid inlet.
198 for separatory means having means to add treating material.

SEE OR SEARCH CLASS:
137, Fluid Handling, subclass 9 for self-proportioning fluid handling processes and subclasses 98+ for self-proportioning apparatus.
222, Dispensing, subclass 57 for dispensing devices which are automatically controlled by the weight, volume or pressure of a second dispensed material, and subclass 130 for plural sources at least one of which is nondispensing.

This subclass is indented under subclass 97. Apparatus governing the order in which individual separatory units of a plurality of such units are used.

This subclass is indented under subclass 97. Apparatus which includes plural sensing means differing characteristics other than mere size.

This subclass is indented under subclass 103. Apparatus responsive to a change in the level of the liquid or solids.

This subclass is indented under subclass 103. Apparatus including the control of introduction of an auxiliary liquid to a treatment chamber.

SEE OR SEARCH THIS CLASS, SUBCLASS:
101 for separatory apparatus combined with means to feed treating material thereto proportionately to the material being treated.

This subclass is indented under subclass 97. Apparatus relating to means to rehabilitate or clean a filter medium.

SEE OR SEARCH THIS CLASS, SUBCLASS:
407 for filter means combined with cleaning means.

This subclass is indented under subclass 106. Apparatus wherein the filter medium or the rehabilitating means is rotated.

SEE OR SEARCH THIS CLASS, SUBCLASS:
359 for a movable filter medium.

This subclass is indented under subclass 106. Apparatus comprising backwash or blowback means.

SEE OR SEARCH THIS CLASS, SUBCLASS:
420 for a filter provided with a flow controller providing selective direction flow therethrough.

This subclass is indented under subclass 97. Apparatus which controls a treated material discharge outlet.

SEE OR SEARCH CLASS:
137, Fluid Handling, 395 for liquid level responsive outlet controls for tanks of general utility, and subclasses 577+ for fluid handling tanks of general utility having adjustable outlets, especially subclass 578 for float supported outlets.

This subclass is indented under subclass 109. Apparatus with means controlling an inlet to a separator.

SEE OR SEARCH THIS CLASS, SUBCLASS:
103 for control by diverse sensing means.

This subclass is indented under subclass 109. Apparatus responsive to liquid to be treated or to an increase in pressure upstream of a filter.

SEE OR SEARCH THIS CLASS, SUBCLASS:
99 for means diverting prefilt to drain responsive to prefilt accumulation.
130 for bypass means responsive to pressure.

This subclass is indented under subclass 109. Apparatus in which the material is a heavier constituent.

This subclass is indented under subclass 112. Apparatus
responsive to weight of accumulated solids.

This subclass is indented under subclass 112. Apparatus responsive to treated liquid accumulation.

This subclass is indented under subclass 112. Apparatus controlling a lighter constituent discharge outlet.

SEE OR SEARCH THIS CLASS, SUBCLASS:
103 for apparatus including diverse sensing means.

This subclass is indented under subclass 109. Apparatus wherein the discharge outlet is normally closed and permits discharge of filtrate responsive to filtrate accumulation.

SEE OR SEARCH THIS CLASS, SUBCLASS:
114 for means controlling discharge of a heavier constituent responsive to treated liquid accumulation.
117 for valve means responsive to change in direction of the flow to prevent backflow.

This subclass is indented under subclass 109. Apparatus including flow control means allowing flow in only one direction.

SEE OR SEARCH THIS CLASS, SUBCLASS:
137 for means maintaining stream pressure or flow in separatory apparatus.

This subclass is indented under subclass 117. Apparatus comprising a variable restrictor responsive to flow direction whereby flow increases during backwash.

This subclass is indented under subclass 117. Apparatus comprising a float operated valve means.

SEE OR SEARCH CLASS:
137, Fluid Handling, 247.15 for line condition change responsive flow controllers combined with liquid seal traps, subclasses 409+ for float operated valves, and subclasses 455+ for line condition responsive valves, especially subclasses 511+ for check valves.

This subclass is indented under subclass 97. Apparatus comprising means controlling an opening above a liquid level for entrance or exit of a gas.

SEE OR SEARCH THIS CLASS, SUBCLASS:
130 for a liquid bypass which may also serve as a vent.
472 for a filter means with vent means.

This subclass is indented under subclass 97. Apparatus in which the responsive means is a float.

SEE OR SEARCH THIS CLASS, SUBCLASS:
104 for diverse sensing means responsive to material level.

This subclass is indented under subclass 121. Apparatus which controls the movement of a separatory medium.

This subclass is indented under subclass 121. Apparatus in which the float controls valve means.

This subclass is indented under subclass 123. Apparatus in which the valve means is located in the flow stream between two separators.

This subclass is indented under subclass 123. Apparatus in which the float and the valve means are on opposite sides of a separatory means.

This subclass is indented under subclass 123. Apparatus in which the float is located in a separate tank or compartment provided for the storage of rehabilitating fluid.

This subclass is indented under subclass 123. Apparatus in which the valve means controls admission of a fluid other than liquid being treated.

SEE OR SEARCH THIS CLASS, SUBCLASS:
101 for a separator with proportionate feed means for adding treating material.
198 for a separator with means to add treating material.

This subclass is indented under subclass 123. Apparatus in which the float is in a nontreating chamber.

SEE OR SEARCH THIS CLASS, SUBCLASS:
126 for a float in separate rehabilitating fluid tank.

This subclass is indented under subclass 128. Apparatus in which the float is in the flow between a controlled inlet and a separator.

This subclass is indented under subclass 97. Apparatus comprising means responsive to pressure to bypass liquids around treatment means.

SEE OR SEARCH THIS CLASS, SUBCLASS:
99 for means to divert on initial charge of prefilt to drain.
790 for separating processes involving dividing and recombining the flow.

This subclass is indented under subclass 130. Apparatus in which the responsive means is a separating element or filter medium which provides a bypass by flexing or compression
thereof or by movement in its entirety.

SEE OR SEARCH THIS CLASS, SUBCLASS:
356 for fluid operated means to flex a filter means during operation.
398 for movable elements within a casing, the movement of which may open a bypass.
738 and 748, for processes including pulsation or oscillation essential to the separation or purification.

This subclass is indented under subclass 130. Apparatus in which the by-pass contains separation or treatment means.

SEE OR SEARCH THIS CLASS, SUBCLASS:
294 for diverse distinct separators.
806 for processes including plural separatory steps.

This subclass is indented under subclass 130. Apparatus in which a separator casing is closed by a unitary attached header which header includes at least an inlet and an outlet and the pressure response bypass means therebetween.

This subclass is indented under subclass 97. Apparatus including plural variable flow affecting elements, at least one of which is controlled by the sensing means.

SEE OR SEARCH THIS CLASS, SUBCLASS:
103 for apparatus including diverse sensing means controlling an operating phase or phases in a separator.
110 for line condition responsive means controlling discharge of treated material and the inlet to a separator.
115 for line condition responsive means controlling discharge of a heavier constituent and discharge of a lighter constituent.

This subclass is indented under subclass 134. Apparatus including at least one manually operated flow controller.

This subclass is indented under subclass 97. Apparatus having means responsive to a change in a flow line condition acting of the face of a valve disc or plug itself to permit flow in one direction only.

SEE OR SEARCH THIS CLASS, SUBCLASS:
103 for diverse sensing means.
117 for a check valve controlling discharge of treated material.
120 for a check valve controlled vent.
130 for a fluid pressure responsive bypass.
416 for valves which form a part of a pump organization.

This subclass is indented under subclass 97. Apparatus to regulate pressure of or rate of flow of a liquid.

SEE OR SEARCH THIS CLASS, SUBCLASS:
111 for means discharging treated material responsive to filter clogging.
114 for means discharging the heavier constituent responsive to treated liquid accumulation.
116 for discharge of treated material responsive to filtrate accumulation.
130 for a fluid pressure responsive bypass.

This subclass is indented under the class definition. Apparatus in which the time at which an element of an treating means is actuated, or the length of time taken to perform an operation thereof is controlled.

SEE OR SEARCH CLASS:
68, Textiles: Fluid Treating Apparatus, subclass 12 and 23+ for treating machines having centrifugal extractor features and time-controlled means associated therewith.

This subclass is indented under subclass 138. Apparatus which introduces to the treating means a fluid in addition to that being treated.

This subclass is indented under subclass 139. Apparatus in which the additional fluid serves to prepare the treating means for a treating operation.

This subclass is indented under the class definition. Apparatus in which an actuating means provides either a continuously repetitive operation of a treating device or a single operation terminating in a position to restart an additional cycle, which cycle is more complex than a mere starting or stopping of a single treating device.

This subclass is indented under subclass 141. Apparatus in which there is a plurality of treating units or sections which are controlled in sequence.

This subclass is indented under the class definition. Apparatus having means to sense some condition of a treatment operation and operate a control device.

SEE OR SEARCH THIS CLASS, SUBCLASS:
86 for a material level responsive indicator.
87 for a fluid flow responsive indicator.
90 for a fluid pressure responsive indicator.
96.1 for control responsive to constituent mixture variation.
97 for control by fluid flow, fluid pressure or material level responsive means.

SEE OR SEARCH CLASS:
137, Fluid Handling, 87.01 for self proportioning or correlated fluid handling systems of general utility.

This subclass is indented under subclass 143. Apparatus responsive to vibration or unbalance of a movable part of treating means.

SEE OR SEARCH THIS CLASS, SUBCLASS:
363 for a centrifugal extractor with rotation stabilizer.

SEE OR SEARCH CLASS:
74, Machine Element or Mechanism, 572 for flywheels and rotors with balancing or vibration dampening means defining no specific feature of separator construction.
192, Clutches and Power-Stop Control, 116 for power-stop control of more general utility.
318, Electricity: Motive Power Systems, 445 for a motor control systems, particularly subclass 460 for vibration responsive control.

This subclass is indented under subclass 143. Apparatus responsive to a condition of rotation of a part of the treating means.

SEE OR SEARCH THIS CLASS, SUBCLASS:
144 for vibration or unbalance responsive control.

SEE OR SEARCH CLASS:
192, Clutches and Power-Stop Control, 103 for a speed responsive clutch for a centrifugal extractor.

This subclass is indented under subclass 145. Apparatus in which there is a treatment casing provided with a closure and a latch controlled by the rotation responsive means.

SEE OR SEARCH CLASS:
192, Clutches and Power-Stop Control, subclass 136 for an automatic cover latch control for a centrifugal extractor.

This subclass is indented under subclass 145. Apparatus which controls a discharge means for a constituent of the class subject matter.

SEE OR SEARCH THIS CLASS, SUBCLASS:
109 for control of discharge responsive to fluid flow, pressure or material level.

This subclass is indented under subclass 143. Apparatus operated accidentally or unintentionally by movement of a container used in a treating operation.

SEE OR SEARCH THIS CLASS, SUBCLASS:
235 for actuation of a flow controller on assembly of parts.

SEE OR SEARCH CLASS:
137, Fluid Handling, subclass 43 for a vent valve opened or closed by the tipping of a container.

This subclass is indented under subclass 143. Apparatus having means responsive to a thermal condition.

This subclass is indented under the class definition. Apparatus consisting of solid contact means to increase the surface area of a liquid in a gas-liquid contact device whereby the contact is enhanced.

SEE OR SEARCH CLASS:
261, Gas and Liquid Contact Apparatus, appropriate subclasses for gas and liquid contact apparatus there provided for.

This subclass is indented under subclass 150. Apparatus combined with a separator.

This subclass is indented under the class definition.
Apparatus combined with (1) means performing an operation external to the subject matter of this class, (2) combined with a static construction installation, (3) specifically related to a particular geos:graphic feature wherein there is included only enough structure foreign to this class (210) to associate it with the apparatus.

SEE OR SEARCH THIS CLASS, SUBCLASS:
241 for a separator combined with a movable support.
244 for a draining type separator comprising a portable receptacle with a hood or closure.
419 for a filter attached to or within a portable prefilt receiver having a flow controller for the material being treated.
464 a portable receptacle draining type filter.
473 for a filter resting on a supporting receiver.

SEE OR SEARCH CLASS:
4, Baths, Closets, Sinks, and Spittoons, appropriate subclasses particularly subclass 652 for strainers combined with sink structure and subclasses 286+ for strainers and stoppers peculiar to that art.
37, Excavating, 318 for a dredger combined with a screen separator.
68, Textiles: Fluid Treating Apparatus, 19 for a laundry machine combined with a fluid extractor, and subclasses 235+ for a separator combined with a washing machine drain.
99, Foods and Beverages: Apparatus, subclass 408 for a deep fat fryer type cooker having crumb or sediment segregation means.
122, Liquid Heaters and Vaporizers, subclass 431 for a filter in a boiler.
137, Fluid Handling, subclass 140 for a siphon combined with a separatory means, and subclasses 343+ for a structural installation of a fluid handling apparatus.
159, Concentrating Evaporators, subclass 42 for a concentrating evaporator combined with a strainer or skimmer.
222, Dispensing, 189.06 for a dispenser with a strainer, and subclass 565 for a sifting dispenser.
435, Chemistry: Molecular Biology and Microbiology, 289.1 for fermentation apparatus including separating means, particularly subclass 295.3 for a bioreactor with the
combination of a draft tube and a semipermeable membrane or filter, subclasses 297.1+ for a bioreactor including a semipermeable membrane or filter, and subclass 308.1 for an apparatus for separating a microorganism from culture media.

This subclass is indented under subclass 153. Apparatus comprising separating means placed in or at the entrance of an open channel confining a flowing stream to prevent solids, such as debris or fish, from passing downstream.

SEE OR SEARCH THIS CLASS, SUBCLASS:
131 for a movable animal stop in a sewer comprising a fluid pressure responsive bypass.
173 for flume stream type separators with comminuting means.

SEE OR SEARCH CLASS:
405, Hydraulic and Earth Engineering, 118 for specific open channel construction or flow control features other than that forming the inlet and outlet to a separator.

This subclass is indented under subclass 154. Apparatus including plural, spaced, straining elements or straining elements of different shapes or kinds.

SEE OR SEARCH THIS CLASS, SUBCLASS:
294 for diverse distinct separators of general utility.
322 for plural distinct separators of general utility.

This subclass is indented under subclass 154. Apparatus moved by the flowing stream or by a collection of residue on the separator medium.

SEE OR SEARCH THIS CLASS, SUBCLASS:
354 for filter structure similarly operated.

This subclass is indented under subclass 156. Apparatus in which the separating medium is a cylindrical filter rotating about a central axis.

This subclass is indented under subclass 154. Apparatus including means for cleaning the filter which is movable.

This subclass is indented under subclass 154. Apparatus including a filter cleaner which is a movable solid means, as a brush, with means to remove residue therefrom.

This subclass is indented under subclass 154. Apparatus in which the separating means is a movable endless foraminous belt.

This subclass is indented under subclass 154. Apparatus in which the separating means is a strainer mounted to revolve in the fluid stream.

This subclass is indented under subclass 154. Apparatus in which the separating means is a strainer stationarily mounted in the fluid stream.

This subclass is indented under subclass 153. Structures including a strainer in outlet means which provide drain means for a surface, as a floor.

SEE OR SEARCH THIS CLASS, SUBCLASS:
116 for a grated surface inlet drain including means responsive to filtrate accumulation permitting discharge of treated material.
119 for a grated surface drains having back-flow preventing means.
247 for a strainer with a filtrate deflector.
459 for a pipe or plate attached filter.

SEE OR SEARCH CLASS:
4, Baths, Closets, Sinks, and Spittoons, appropriate subclasses, particularly 268, 275+, 286+, 596+, 640+, and 650+ for plumbing apparatus including drains with grated inlets.
52, Static Structures (e.g., Buildings), subclass 12 for cover with an eave or valley gutter with a separator.
285, Pipe Joints or Couplings, subclass 42 for flashed pipe-to-plate joint.
404, Road Structure, Process, or Apparatus, 2 for roadway drain or gutter structure.

This subclass is indented under subclass 163. Structures where the upper face of the strainer is flat and is level with its associated surface.

This subclass is indented under subclass 164. Structures which include means to dispose of subsurface seepage e.g., weep holes.

SEE OR SEARCH CLASS:
285, Pipe Joints or Couplings, subclass 14 for a pipe joint including leakage or drip disposal means comprising a weep hole.

This subclass is indented under subclass 163. Apparatus comprising a concentric ring or rib between the strainer and its associated surface wherein the ring or rib projects above the plane of the surface.

This subclass is indented under subclass 153. Apparatus with means to recirculate a liquid therebetween.

SEE OR SEARCH THIS CLASS, SUBCLASS:
194 for purifiers or separators with recirculation means.

SEE OR SEARCH CLASS:
68, Textiles: Fluid Treating Apparatus, subclass 18 for a recirculating system including a fluid textile treating means and purifying means for the used solvent.
118, Coating Apparatus, 600 for coating apparatus with means for treatment of the coating material involving separation and recirculation.
123, Internal-Combustion Engines, subclass 41.55 for internal and combustion engine cooling system combined with a strainer, and subclass 196 for internal combustion engine lubricator means combined with liquid purifying means.
134, Cleaning and Liquid Contact With Solids, 10 and 109+ for cleaning and liquid contact processes and apparatus having means for rehabilitating the treating fluid.

This subclass is indented under subclass 167. Systems designed to lubricate moving parts of a machine.

SEE OR SEARCH CLASS:
123, Internal-Combustion Engines, subclass 196 for lubricators including rehabilitating means there provided for.
184, Lubrication, subclass 1.5 for crankcase service apparatus including separators, and subclass 6 for lubricating systems including separators.

This subclass is indented under subclass 167. Systems designed to accommodate living animals.

SEE OR SEARCH THIS CLASS, SUBCLASS:
220 for a submerged fluid inlet means to add treating material to a separator.

SEE OR SEARCH CLASS:
119, Animal Husbandry, 259 for specific aquarium structure in combination with liquid purification or separation means.

This subclass is indented under subclass 153. Apparatus in which a separator is part of a system installed in the ground or related to a particular geos:graphic feature, as a lake.
(1) Note. Included in this subclass is in situ purging of flowing or still liquid (e.g., drainage ditch, septic system, pond) wherein a structural installation in which the separator or purifier is (a) part of a system installed on natural or modified terrain to convey rain, snow melt, a river, sewage, well water or oil, etc. or (b) related to a particular nonland geos:graphic feature, such as a lake, ocean, sea, etc.

SEE OR SEARCH THIS CLASS, SUBCLASS:
154 for a flume stream type separator.

SEE OR SEARCH CLASS:
137, Fluid Handling, subclass 236.1 for a distribution system involving a geos:graphical feature.
405, Hydraulic and Earth Engineering, 36 for drainage devices and 52+ for fluid control or inhibiting the formation of, containing the spread of, or settling an undesirable floatable or suspended material in a body of water (i.e., treatment).

This subclass is indented under subclass 153. Apparatus including means having moving parts.

SEE OR SEARCH THIS CLASS, SUBCLASS:
168 for machinery with lubrication means in recirculating relationship with a separator.

SEE OR SEARCH CLASS:
68, Textiles: Fluid Treating Apparatus, subclass 208 for fluid textile treating means having a drain and strainer means associated therewith.
118, Coating Apparatus, subclass 610 for reconditioning by separation of coating materials.
134, Cleaning and Liquid Contact With Solids, subclass 104 for cleaning apparatus having material collectors (e.g., strainers) for escaping cleaning liquid.

This subclass is indented under subclass 153. Apparatus including a supply tank for an apparatus or a system having a function external to the subject matter of this class and purification is incidental to the storage of the liquid for use in that system or apparatus.

This subclass is indented under the class definition. Apparatus comprising unitary separators and means to comminute solids.

SEE OR SEARCH THIS CLASS, SUBCLASS:
154 for a flume stream type separator, per se.
359 for a movable filter or separator which may break up "flocs" or residue incidental to agitation or material handling.
407 for a filter having means for agitation of the liquid.
769 for related processes.

SEE OR SEARCH CLASS:
241, Solid Material Comminution or Disintegration, and see the reference to Class 210 in section 8 of the class definition.

This subclass is indented under subclass 173. Apparatus in which the separating medium comprises a cylindrical filter medium.

SEE OR SEARCH THIS CLASS, SUBCLASS:
161 for a revolvable flume screen strainer, per se.
402 for a movable drum type filter.

This subclass is indented under the class definition. Apparatus having heat exchanging means comprising an imperforate heat transfer member, radiant heater or heat generator.

SEE OR SEARCH THIS CLASS, SUBCLASS:
768 for separating processes with treatment of separated solids, and subclasses 774+ for separating processes involving treatment by heating or cooling.

SEE OR SEARCH CLASS:
62, Refrigeration, for refrigeration means or steps combined with fluid cooling or gas liquefaction or solidification. For particular subclasses in Class 62 involving refrigeration and fluid separation, see the reference to Class 62 in the class definition of this class (210).
96, Gas Separation: Apparatus, appropriate subclasses for gas separation apparatus combined with heating or cooling means.
122, Liquid Heaters and Vaporizers, 379 for processes and apparatus for cleaning liquid heaters or vaporizers or for purifying the water while the boiler is in operation.
126, Stoves and Furnaces, subclass 343.5 for melting furnaces which may include liquid separating means.
159, Concentrating Evaporators, subclass 42 for strainers or skimmers specialized for that class.
165, Heat Exchange, subclass 119 for a heat exchange with an ancillary filter.
202, Distillation: Apparatus, subclass 178 for combined distilland preheater and strainer, and subclasses 202+ for still with condensate treating means.
266, Metallurgical Apparatus, 277 for apparatus for separating molten metal for undesired constituents.

This subclass is indented under subclass 175. Apparatus which separate a liquid mixture into two or more dissimilar fractions by subjecting a thin film of liquid mixture to a temperature gradient.

SEE OR SEARCH THIS CLASS, SUBCLASS:
775 for related processes.

This subclass is indented under subclass 175. Apparatus having means for adding a treating fluid.

This subclass is indented under subclass 177. Apparatus in which the separator is provided with a mechanical agitator or in which the separating medium is movable.

This subclass is indented under subclass 175. Apparatus provided with mechanical agitating means or with means for moving a separator.

SEE OR SEARCH THIS CLASS, SUBCLASS:
178 for similar structure with addition of treating fluid.

This subclass is indented under subclass 175. Apparatus provided with means to remove vapor or gas.

SEE OR SEARCH THIS CLASS, SUBCLASS:
472 for a vented filter.

This subclass is indented under subclass 175. Apparatus in which a heater or heat exchanger is connected in series by a flow line for the liquid under treatment.

SEE OR SEARCH THIS CLASS, SUBCLASS:
252 for other serially connected distinct treating or storage units.

This subclass is indented under subclass 175. Apparatus in which the separators are of different kinds.

SEE OR SEARCH THIS CLASS, SUBCLASS:
294 for other diverse distinct separators.

This subclass is indented under subclass 182. Apparatus wherein the heat exchanger is coaxial with the casing enclosing the diverse separators.

This subclass is indented under subclass 175. Apparatus wherein the separator is a filter.

This subclass is indented under subclass 184. Apparatus in which the heat exchanger is embedded in the filter medium or is sandwiched between filter media.

This subclass is indented under subclass 184. Apparatus wherein the heat exchanger is external of the means confining the liquid undergoing treatment.

This subclass is indented under subclass 175. Apparatus in which the heat exchanger is within a liquid holding container of a gravitational separator.

This subclass is indented under the class definition. Apparatus combined with a gas or vapor separator, which is more than a mere vent and must (1) remove gases evolved during a treating operation or (2) treat gas removed from a Class 210 separator.

SEE OR SEARCH THIS CLASS, SUBCLASS:
472 for a filter with vent means.
539 for a gravitational separator having a vent.

SEE OR SEARCH CLASS:
96, Gas Separation: Apparatus, for apparatus for gas separation, per se. See the Class 210 class definition for an amplification of the line.

This subclass is indented under the class definition. Apparatus comprising means providing distinct chambers or areas for solid-liquid contact with means for circulating granular separatory material between at least two of the chambers.

SEE OR SEARCH THIS CLASS, SUBCLASS:
268 for a separator having means providing gravity flow of particles therethrough.
270 for moving rehabilitation means which pick up and redeposit particles on the same bed.
271 for surface traversing rehabilitation means for a particulate material bed.

This subclass is indented under the class definition. Apparatus in which means is provided for the purpose of conveying, preparing or storing a liquid which is used to restore a chemical affinity of the separatory medium.

This subclass is indented under subclass 190. Apparatus including a pump, injector or siphon.

This subclass is indented under the class definition. Systems comprising means to make one or more of the chemical reagents used in the treatment combined with apparatus of this class.

SEE OR SEARCH THIS CLASS, SUBCLASS:
715 for processes of seeding with sludge of the system.
716 for processes including reagent manufacture.

SEE OR SEARCH CLASS:
422, Chemical Apparatus and Process Disinfecting, Deodorizing, Preserving, or Sterilizing, 186.8 for ozonizers with preparatory or product treating means; and subclass 186.23 for arc or spark discharge reactors having preparatory or product treating means.

This subclass is indented under the class definition. Apparatus with means to apply an additional solid material usually discrete particles, as a coating to a filtering medium, the additional material then acting as a primary filtering medium.

SEE OR SEARCH THIS CLASS, SUBCLASS:
503 for diverse granular or fibrous filter materials.
506 for a coated or impregnated filter material.
777 for separating processes including use of a filter aid.

This subclass is indented under the class definition. Apparatus in which at least a portion of the fluent material is circulated in a closed circuit from and back to the separator.

SEE OR SEARCH THIS CLASS, SUBCLASS:
167 for a closed circulating system in a structural installation.
189 for separatory apparatus including means to circulate filter particles between plural chambers.
621 712+, 765, and 805, for separating processes including recirculation.
779 for processes with residual returned to prefilt.

SEE OR SEARCH CLASS:
137, Fluid Handling, subclass 268 for infiltration means ancillary to a fluid handling system, and subclass 563 for a closed circulating system of general utility.
204, Chemistry: Electrical and Wave Energy, subclass 238 for an electrolytic cell which includes a filter and recirculating means.

Serially connected distinct treating or storage units:
This subclass is indented under subclass 194. Apparatus including two or more vessels connected in series or two or more zones in a single vessel separated by a baffle connected in series.
(1) Note. The vessels or zones may be either functionally or physically distinct from one another.

With semipermeable membrane, e.g., dialyzer, etc.:
This subclass is indented under subclass 195.1. Apparatus including a septum selective as to composition.

With sediment recycle means directly to main stream:
This subclass is indented under subclass 195.1. Apparatus including means to return sediment to a point upstream with respect to the flow of material to be treated, which means provides for recombination of the sediment with the material to be treated.

Means is baffle slot:
This subclass is indented under subclass 195.3. Apparatus in which the means to return sediment is an aperture in a wall dividing a vessel into separate treating zones.

This subclass is indented under subclass 194. Apparatus in which filtrate is returned to prefilt.

SEE OR SEARCH THIS CLASS, SUBCLASS:
409 for a filter with fluid cleaning involving mere return of filtrate for backwashing.

This subclass is indented under subclass 194. Apparatus in which the material recirculated is removed from a bottom portion of the separator.

SEE OR SEARCH THIS CLASS, SUBCLASS:
713 for processes of precipitation including return of removed solids to the separator.

WITH MEANS TO ADD TREATING MATERIAL:
This subclass is indented under the class definition. Apparatus combined with means to add a treating material.
(1) Note. By "treating material" is meant (a) a material, usually a fluid, having a function other than rehabilitating a separating medium or cleaning a separator, (b) a fluid merely serving as a source of pressure, or (c) a fluid not in itself serving as a separating medium.

SEE OR SEARCH THIS CLASS, SUBCLASS:
96.1 for separators with constituent mixture variation controls.
101 for flow fluid pressure or material level proportional feed means.
105 for diverse sensing including control means for an auxiliary liquid inlet.
127 for a float controlled valve controlling an additional fluid inlet.
151 for a separator and gas-liquid surface contact means.
177 for separators with a heater or heat exchanger and treating fluid addition means.
192 for a separator with preliminary chemical manufacturing means.
296 and 511, for separators using a liquid as a separating medium.
601 particularly subclasses 11 and 15+, for processes of teating by living organisms.
633 and 634+, for processes of extraction from liquid by solvent or solute.

SEE OR SEARCH CLASS:
137, Fluid Handling, 87.01 for self-proportioning and correlating systems; and subclass 268 for holders for materials to be entrained into a fluid handling system.
261, Gas and Liquid Contact Apparatus, 2 for such apparatus combined with means for separating constituents from the contact liquid; and subclasses 75+ for gas and liquid contact devices, per se.
422, Chemical Apparatus and Process Disinfecting, Deodorizing, Preserving, or Sterilizing, for extracting, leaching, or dissolving apparatus.
423, Chemistry of Inorganic Compounds, appropriate subclasses for extracting, leaching, or dissolving processes therein provided for; and subclass 658.5 for extracting, leaching, or dissolving processes not otherwise provided for.

Chromatography:
This subclass is indented under subclass 198.1. Apparatus for carrying out the process of chromatography.

SEE OR SEARCH THIS CLASS, SUBCLASS:
656 for process involving chromatography.

Thin layer, e.g., plate, etc:
Apparatus under subclass under 198.2 utilizing an absorbent cake spread on usually a smooth plate to a depth of about 0.5 mm.

This subclass is indented under subclass 198.1. Apparatus wherein at least two distinct treating material feeding means supply to inlets spaced with respect to the direction of the flow of material being treated.

This subclass is indented under subclass 198.1. Systems comprising a plurality of distinct separating means.

SEE OR SEARCH THIS CLASS, SUBCLASS:
294 for diverse distinct separators.

This subclass is indented under subclass 200. Systems connected in such a manner that at least one of the separating means delivers to another.

SEE OR SEARCH CLASS:
137, Fluid Handling, 571 for plural tanks or compartments connected for serial flow.

This subclass is indented under subclass 201. Systems comprising at least two different types of separating means.

This subclass is indented under subclass 200. Apparatus having two or more filtering units.

This subclass is indented under subclass 203. Apparatus in which the filters are of the sectional chamber press type.

SEE OR SEARCH THIS CLASS, SUBCLASS:
224 for other sectional press type filters.

This subclass is indented under subclass 198.1. Systems comprising structure providing a distinct reactor tank, trough or compartment wherein the plural in-flows are intermingled to enhance reaction (e.g., precipitation), said tank, trough or compartment being in series with the separator.

SEE OR SEARCH THIS CLASS, SUBCLASS:
209 for tanks, troughs or compartments which serve both as a reactor and as a separator.

This subclass is indented under subclass 205. Apparatus comprising a single flow path having the separating means in seral relation with means for holding a chemical.

SEE OR SEARCH THIS CLASS, SUBCLASS:
199 for plural material inlets spaced along a flow path.

This subclass is indented under subclass 205. Apparatus wherein the reactor tank, trough or compartment is located within the separator which is of the gravitational type.

This subclass is indented under subclass 207. Systems comprising movable mechanical means to cause materials to commingle.

SEE OR SEARCH THIS CLASS, SUBCLASS:
407 for fixed filter and liquid agitating means.

This subclass is indented under subclass 198.1. Apparatus provided with means to add the treating material directly to the separator.

SEE OR SEARCH CLASS:
68, Textiles: Fluid Treating Apparatus, appropriate subclasses for textile treating apparatus combined with a liquid remover, particularly subclass 1 for waste reclaiming apparatus, subclasses 5+ for gas steam or mist treating, subclass 18 for solvent recovery, and subclasses 19+ for fluid extractor combinations.
127, Sugar, Starch, and Carbohydrates, 16 for means for purging sugar crystals.

This subclass is indented under subclass 209. Apparatus wherein the material to be separated and the treating material are directly introduced into the interior space of the separator element which moves.

SEE OR SEARCH CLASS:
68, Textiles: Fluid Treating Apparatus, subclass 12 and 237 for textile treating apparatus having textile washing features in addition to a liquid extractor.
422, Chemical Apparatus and Process Disinfecting, Deodorizing, Preserving, or Sterilizing, 258 and 269+ for rotary extractor or leacher.

This subclass is indented under subclass 210. Apparatus in which the separator is supported on a rotary shaft having passage means therein through which the treating material is introduced.

This subclass is indented under subclass 210. Apparatus in which the filtering rotor is enclosed in a casing having a closure and means attached to or projecting through the closure for feeding treating material to the rotor.

This subclass is indented under subclass 210. Apparatus in which the filter element is rotary and there is a rotary impeller or distributor for the treating material which is coaxial with the axis of rotation of the filter element.

This subclass is indented under subclass 210. Apparatus comprising a distributor for the treating material mounted upon a stationary support and movable with respect to such support.

This subclass is indented under subclass 210. Apparatus including means for dividing the separated effluent into a plurality of fractions.

SEE OR SEARCH THIS CLASS, SUBCLASS:
378 for a centrifugal extractor with a filtrate receiving means having plural filtrate outlets.

This subclass is indented under subclass 209. Apparatus by which the additional material is applied to a moving filter medium.

This subclass is indented under subclass 216. Apparatus in which the moving filter medium comprises a rotary drum.

This subclass is indented under subclass 209. Apparatus provided with means to remove gases or vapors from a liquid treating tank which is closed except for fluid handling inlets and/or outlets.

SEE OR SEARCH THIS CLASS, SUBCLASS:
472 for a vented filter.

This subclass is indented under subclass 209. Apparatus in which there is a mechanical agitator.

SEE OR SEARCH THIS CLASS, SUBCLASS:
402 for a drum having an agitator fixed thereto.
407 for fixed filters with liquid agitating means.

This subclass is indented under subclass 209. Apparatus in which the exit from the additional fluid introducing means is submerged in the liquid being treated.

SEE OR SEARCH CLASS:
43, Fishing, Trapping, and Vermin Destroying, 56 for minnow buckets having aerating means.
261, Gas and Liquid Contact Apparatus, 121 for submerged blast liquid and gas contact devices.

With outlet at surface, e.g., froth:
This subclass is indented under subclass 220. Apparatus in which there is a means to remove a lighter constituent.

SEE OR SEARCH CLASS:
209, Classifying, Separating, and Assorting Solids, 162 for flotation processes and apparatus for separating one solid component from another.

And gas injecting means other than by mechanical agitation:
This subclass is indented under subclass 221.1. Apparatus having means to produce a gas other than mechanical agitation.

This subclass is indented under the class definition. Apparatus including magnetic treating means.

SEE OR SEARCH THIS CLASS, SUBCLASS:
695 for processes of precipitation which may involve magnetic separation.

SEE OR SEARCH CLASS:
204, Chemistry: Electrical and Wave Energy, particularly 155 for the production of a compound or element by chemical reaction brought about by electrical or wave energy in a magnetic field; subclasses 157.15+ for processes of treating materials involving a chemical reaction brought about by wave energy; and subclasses 660+ for a liquid treatment apparatus which is specialized for: magnetic treatment, per se, when some effect other than mere separation is desired or produced or simultaneous electrical and magnetic separation of the liquid which does not result in the production of a compound or element by chemical reaction brought about by electrical or wave energy in a magnetic field.
209, Classifying, Separating, and Assorting Solids, subclass 38, 39, 40, 212, 213+, and 478 for processes and apparatus involving applying a magnetic field to material (which may be suspended in a liquid) for the purpose of separating one solid component from another.
335, Electricity: Magnetically Operated Switches, Magnets, and Electromagnets, 209 for magnets and electromagnets, per se.

This subclass is indented under subclass 222. Apparatus in which there is at least one separating means, other than the magnet.

This subclass is indented under the class definition.
Apparatus comprising abutting filter plates or alternating abutting filter plates and spacing frames which are pressed together by at least one movable end member, the end members, plates and/or frames when pressed together constituting a casing which is closed except for fluid handling connections.

SEE OR SEARCH THIS CLASS, SUBCLASS:
185 for heater or heat exchanger combinations wherein the heater or heat exchanger is embedded or between filter media.
323 for plural distinct filters.
445 for a filter element clamped in a casing joint.

SEE OR SEARCH CLASS:
100, Presses, appropriate subclasses particularly 113 and 194+ for presses which force filter plates or frames towards each other to express the liquid by mechanical pressure.

This subclass is indented under subclass 224. Apparatus provided with residue removal or liquid agitation means.

This subclass is indented under subclass 224. Apparatus in which the filtering medium comprises a mass of fibers or discrete particles within the filter plates or frames.

SEE OR SEARCH THIS CLASS, SUBCLASS:
263 for a particulate material type separator.
317 for spaced diverse filters including nonself supporting media.
343 for stacked elements having liquid distributors separating filter media, including porous masses.
417 for a liquid distributor imbedded in a filter mass.

This subclass is indented under subclass 224. Apparatus in which the filtering medium is clamped at and between the peripheral edges of plate or frame sections.

SEE OR SEARCH THIS CLASS, SUBCLASS:
445 for other filter mediums clamped in a casing joint.

This subclass is indented under subclass 227. Apparatus in which the filtering medium is clamped at and between the peripheral edges of the spacing frames and filter plate sections.

This subclass is indented under subclass 227. Apparatus in which the filter sections are of I or channel cross-section forming a recess, the web of which is imperforate except for filtrate drain openings, and the filter medium abuts the web within the recess.

SEE OR SEARCH THIS CLASS, SUBCLASS:
455 for modified spacing surfaces or supports for a filter medium.

This subclass is indented under subclass 224. Apparatus including means for assembly or disassembly or to restore or aid in restoring the device to its former condition after decay.

This subclass is indented under subclass 224. Apparatus
comprising frame and/or plate structure, per se, restricted to use with sectional chamber press type filter elements.

SEE OR SEARCH THIS CLASS, SUBCLASS:
230 for plates and frames having supporting means which aid in assembling and disassembling.
541 for separator adjuncts of general application.

SEE OR SEARCH CLASS:
100, Presses, 295 for platens or pressure surfaces there provided for.

This subclass is indented under the class definition. Apparatus which is provided with auxiliary means, in addition to the parts making up the separation or treatment apparatus or the means to secure said parts in operative relation, to aid in assembling or disassembling said apparatus or a subcombination thereof; or to restore, or aid in restoring the apparatus or a subcombination thereof to its former condition after decay, injury, or partial destruction.

SEE OR SEARCH THIS CLASS, SUBCLASS:
230 for a sectional chamber press having repair or assembly means.
329 for separators relatively movable during treatment.
350 for adjustable means compressing a filter medium within a container even though the operator for the compressing means can be moved to inoperative position.

SEE OR SEARCH CLASS:
137, Fluid Handling, subclasses 315.01-329.4 for a fluid handling system with repair, tapping, or assembly means.

This subclass is indented under subclass 232. Apparatus for piercing a container, or for knocking out a closure.

SEE OR SEARCH THIS CLASS, SUBCLASS:
235 for a device in which placement of a container opens a flow controller.
240 for a sealed filter unit provided with a frangible or knockout section for conversion of flow direction.

This subclass is indented under subclass 232. Apparatus comprising a treatment part arranged to be removable and a valve in flow relationship thereto biased to close but being maintained open in normal use of the part.

SEE OR SEARCH THIS CLASS, SUBCLASS:
235 for a device in which placement of a container opens a flow controller.

This subclass is indented under subclass 232. Apparatus in which the placement of a container opens a flow controller.

SEE OR SEARCH THIS CLASS, SUBCLASS:
234 for a treatment part maintaining a controller open when in position.

This subclass is indented under subclass 232. Apparatus including guide means, on which the element to be assembled or disassembled rolls or slides.

SEE OR SEARCH THIS CLASS, SUBCLASS:
241 for a separator mounted on a movable support.

This subclass is indented under subclass 232. Apparatus
comprising (1) a handle attached to a separating element, or (2) means attached to a separating element cooperating with a hoist.

SEE OR SEARCH THIS CLASS, SUBCLASS:
249 for a leg, hanger or bracket for a filter assembly.

This subclass is indented under subclass 237. Apparatus which is hand manipulable.

SEE OR SEARCH THIS CLASS, SUBCLASS:
244 for a portable receptacle having a closure with a handle.
464 for a handled portable receptacle and drainer.
470 for a filter element having handle means.

This subclass is indented under the class definition. Apparatus so constructed that its mode of operation can be changed by reassembling all or some of its parts in a different relationship to each other or by addition or omission of a part.

SEE OR SEARCH THIS CLASS, SUBCLASS:
473 for a filter unit having adjustable supporting means or having plural supporting surfaces.

This subclass is indented under subclass 239. Apparatus comprising selectively assembable separate flow connections.

This subclass is indented under the class definition. Apparatus which is movably supported.

SEE OR SEARCH THIS CLASS, SUBCLASS:
236 for slide or roller guide means for assembly.
237 for assembling hoist or handle means.
249 for a bracket or leg support for a static separator assembly.
271 for the mounting of rehabilitation means for movement with respect to a particulate bed.
359 for a filter having a medium movable for treating purposes.

SEE OR SEARCH CLASS:
137, Fluid Handling, 899 for a vehicle mounted distribution system.
209, Classifying, Separating, and Assorting Solids, subclass 421 for a vehicle mounted sifter.

Float:
This subclass is indented under subclass 241. Apparatus in which the assembly is buoyantly supported.

SEE OR SEARCH THIS CLASS, SUBCLASS:
121 for fluid flow or material level responsive floats having a controlling function.

With aerating means:
This subclass is indented under subclass 242.1. Apparatus having means to inject a gas.

With oil water skimmer:
This subclass is indented under subclass 242.1. Apparatus
having means to remove the top layer of the oil water system.

With oil water sorption means:
This subclass is indented under subclass 242.1. Apparatus having means to soak up a portion of the oil water system.

This subclass is indented under the class definition. Apparatus in which parts are electrically insulated or there is means to discharge electricity.

SEE OR SEARCH CLASS:
361, Electricity: Electrical Systems and Devices, 212 for static electricity discharging of more general utility.

This subclass is indented under the class definition. Apparatus comprising a filter incorporated in a portable receptacle not having any flow connections attached thereto, which receptacle is provided with (1) a hood, or (2) means forming a complete closure of the top side thereof, which closure may have a foraminous section provided with means for completely covering such section.

SEE OR SEARCH THIS CLASS, SUBCLASS:
380 for a rotating centrifugal extractor element having a removable closure.
464 for a portable receptacle draining type filter.
473 for a filter removably supported on a portable container.

SEE OR SEARCH CLASS:
141, Fluid Material Handling, With Receiver or Receiver Coacting Means, appropriate subclasses, for fluent material handling devices, with receiver or receiver coacting means.
220, Receptacles, 24 for receptacle closures, subclasses 694+ for attachments for receptacles.
222, Dispensing, 189.06 for a dispenser having a filter.
297, Chairs and Seats, 175 for a seat combined with a pail or the like for milking operations.

This subclass is indented under subclass 244. Apparatus in which there is a controlling means mounted on or supported by the closure.

SEE OR SEARCH THIS CLASS, SUBCLASS:
418 for a filter and flow controller, per se.

This subclass is indented under subclass 244. Apparatus provided with means for holding the cover for limited movement with respect to the upper edge of the receptacle so that solids will be retained and liquid escape between the cover and the receptacle upper edge.

SEE OR SEARCH THIS CLASS, SUBCLASS:
382 for a centrifugal extractor having a discharge between the upper edge of a receptacle and a cover therefor.
464 for a portable receptacle with attached strainer for draining.

This subclass is indented under the class definition. Apparatus provided with a splash plate or deflector located downstream of and spaced from a filter medium.

SEE OR SEARCH THIS CLASS, SUBCLASS:
456 for a filter with a prefilt flow director or diverter.

This subclass is indented under the class definition. Apparatus with (1) means for receiving drip or overflow, or (2) means to receive the contents of a filter unit when it is disassembled.

SEE OR SEARCH THIS CLASS, SUBCLASS:
299 particularly subclasses 312+ for a filter and sediment trap with drain means.

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222, Dispensing, 108 for a dispenser with drip, leakage or waste catching features.

This subclass is indented under the class definition. Apparatus provided with a bracket, hanger or leg support for an entire separating assembly.

SEE OR SEARCH THIS CLASS, SUBCLASS:
468 for a filter having means for supporting it from a receptacle spout.

SEE OR SEARCH CLASS:
248, Supports, appropriate subclasses particularly subclass 94 for a support for a strainer or funnel.

This subclass is indented under subclass 249. Apparatus in which the filter assembly is supported by means extending directly below and freely resting on a base or attached to a base.

SEE OR SEARCH CLASS:
248, Supports, subclass 188 for leg attaching connections for stands, and subclasses 188.1+ for supporting substructure for a stand.

This subclass is indented under the class definition. Apparatus comprising a device in addition to or combined with separator structure or liquid purification apparatus (1) having functions other than purification or separation, or (2) serving to perfect the purification or separation apparatus for its intended purpose.

SEE OR SEARCH THIS CLASS, SUBCLASS:
85 for apparatus with a single, indicator, register, recorder or inspection means.
151 for gas liquid surface contact means and a separator.
153 for treating apparatus of this class in another installation not sufficiently included to form a basis of classification in the other art class.
173 for a separator structurally combined with a comminutor.
175 for treating apparatus with heat exchange.
188 for a liquid separator and a gas separator.
192 for treating apparatus with preliminary chemical manufacture.
239 for a convertible feature of treating apparatus.
241 for treating apparatus with a movable support.
243 for electrical insulating or discharging.
249 for a support for a separator.
418 for a filter and a flow controller.
456 for prefilt restrictors or diverters.

SEE OR SEARCH CLASS:
4, Baths, Closets, Sinks, and Spittoons, 286 for strainers in devices of that type.

This subclass is indented under the class definition. Apparatus comprising plural distinct treating or storage casings connected by means for transferring material from one unit to another.

SEE OR SEARCH THIS CLASS, SUBCLASS:
172 for a separator ancillary to a storage tank for a system or apparatus having a function external of this class.
181 for flow line connected heater or heat exchanger.
201 for similar subject matter with means to add material.

This subclass is indented under subclass 252. Apparatus in which two or more units are in parallel.

This subclass is indented under subclass 252. Apparatus in which there is a means to bypass one or more units.

SEE OR SEARCH THIS CLASS, SUBCLASS:
130 for a fluid pressure responsive bypass.
433 for a bypass around a filter.

This subclass is indented under subclass 252. Apparatus in which the units or parts thereof are in stepped relationship.

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262 for serial diverse units one above another.

This subclass is indented under subclass 252. Apparatus in which one unit is within another.

SEE OR SEARCH THIS CLASS, SUBCLASS:
207 for a distinct reactor, tank trough or compartment within a gravitational separator.
315 for a diverse spaced filter within another.
337 for nested distinct separators in series.
342 for one separator within another.

With storage unit:
This subclass is indented under subclass 252. Apparatus in which at least one of the units merely holds liquid.

SEE OR SEARCH CLASS:
137, Fluid Handling, 571 for plural tanks or compartments connected for serial flow.
184, Lubrication, subclass 1.5 for crankcase service apparatus including separators.

Having membrane:
This subclass is indented under subclass 257.1. Apparatus constructed with a filtering means composed of a thin, enveloping or lining substance, i.e., membrane.

SEE OR SEARCH THIS CLASS, SUBCLASS:
96.2 for a membrane in an apparatus with constituent mixture variation responsive.
348 for apparatus which uses a semipermeable septum which does not provide for continuous streams on both sides of the septum.
433 for similar apparatus which uses an ordinary filter septum.
500.1 for a membrane, per se.
541 for membrane supports, frames, and spaces.
634 for process of using a septum selective as to composition.

SEE OR SEARCH CLASS:
127, Sugar, Starch, and Carbohydrates, subclass 10 for a sugar solution dialyzer.
204, Chemistry: Electrical and Wave Energy, 252 for a similar device using an electric current.
604, Surgery, subclass 4.01, 5.01-5.04, 6.01-6.09, 6.01, 6.11-6.16 for drawing blood from the body, treating the blood, and returning it the body.

This subclass is indented under subclass 252. Apparatus provided with (1) a pump, (2) means to supply a gas under pressure to cause fluid flow, or (3) means for applying a vacuum to at least one of the units.

SEE OR SEARCH THIS CLASS, SUBCLASS:
406 for a filter with a vacuumized filtrate receiver.
416 for a filter with a pump, gas pressure or vacuum source.

Apparatus under subclas 252 in which the units differ from each other as to their separating structure.

SEE OR SEARCH THIS CLASS, SUBCLASS:
294 for diverse distinct separators.

This subclass is indented under subclass 259. Apparatus in which more than one operation is accomplished in a single unit.

This subclass is indented under subclass 259. Apparatus in which one unit supports another.

This subclass is indented under subclass 259. Apparatus in which units are at different levels.

SEE OR SEARCH THIS CLASS, SUBCLASS:
255 for serial units in cascade relationship.
261 for serial units in which one supports another.

This subclass is indented under the class definition. Apparatus comprising a bed of discrete particles each capable of movement within the bed and readily separable from each other.

SEE OR SEARCH THIS CLASS, SUBCLASS:
118 for flow of fluid pressure responsive operation of sand valves.
189 for plual chambers with movement of granules therebetween.
190 for a separator with external supply means for regenerating material in, water softening systems,
193 for a filter with precoat adding or supplying means.
226 for a sectional chamber press type filter with a porous filler.
317 for spaced filters including a nonself-supporting medium.
350 for a filter with movable means to compress a medium.
500.1 for filter materials, particularly subclasses 503+ for diverse granular or fibrous materials.
615 for processes of aerobic treatment utilizing contact surfaces.
660 for processes involving ion exchange or sorption.
767 for separating processes, particularly subclasses 777+ for processes employing precoats or filter-aids, and subclass 80 for separating and rehabilitation of a particulate bed.

SEE OR SEARCH CLASS:
96, Gas Separation: Apparatus, 108 for solid sorbent apparatus for gas separation.
166, Wells, subclass 51 and 278 for processes of and apparatus for forming gravel filters in wells.

This subclass is indented under subclass 263. Apparatus comprising a plurality of compartments, and means for using and/or rehabilitating the particles in each compartment selectively.

SEE OR SEARCH THIS CLASS, SUBCLASS:
102 for programming of plural units by means responsive to flow, fluid pressure or material level responsive means.
142 for program actuated sequentially controlled plural units or sections.

This subclass is indented under subclass 263. Apparatus combined with a gravitational separator.

This subclass is indented under subclass 263. Apparatus combined with an additional separating means other than a particulate material type and spaced therefrom.

SEE OR SEARCH THIS CLASS, SUBCLASS:
265 for a gravitational separator combined with a particulate material.
273 279, 289, and 291+, for a particulate material type separator having a fluid distributor even though such distributor be foraminous and may incidentally separate large particles.
283 for a pervious separator contacting and between particulate beds.

This subclass is indented under subclass 263. Apparatus in which the bed of separating material is contained in a casing mounted for rotation.

SEE OR SEARCH THIS CLASS, SUBCLASS:
399 for another filter element mounted within a closed movable casing.

This subclass is indented under subclass 263. Apparatus in which means is provided for removing particles from the bottom of the bed so that the bed of separating material as a whole moves downwardly by gravity.

SEE OR SEARCH THIS CLASS, SUBCLASS:
189 for apparatus wherein the particles are moved between plural containers or plural compartments in the same container.
270 for apparatus which is provided with moving means to pick up and redeposit the particles during rehabilitation.

This subclass is indented under subclass 263. Apparatus in which means is provided for restoring the separating medium to the condition it was in before separation.

SEE OR SEARCH THIS CLASS, SUBCLASS:
189 for such a device with a separate rehabilitation chamber.
190 for a chamber provided with external regenerating medium supply.
407 for a filter combined with residue removal of liquid agitation means.
656 and 660+, for processes of ion exchange or sorption involving rehabilitation of the separation medium.
791 for separating processes involving rehabilitation of a filtering medium.

This subclass is indented under subclass 269. Apparatus having moving means to pick up particles from the bed and redeposit them on the bed.

SEE OR SEARCH THIS CLASS, SUBCLASS:
189 for apparatus wherein the particles are moved between plural containers or plural compartments in the same container.
268 for a particle type separator with gravity flow of the particles from the bottom of the bed.

SEE OR SEARCH CLASS:
299, Mining or In Situ Disintegration of Hard Material, 7 for mining combined with separating.

This subclass is indented under subclass 269. Apparatus having rehabilitation means which moves in a path parallel to and above the upper bed surface with or without parts projecting into the bed.

SEE OR SEARCH THIS CLASS, SUBCLASS:
270 for apparatus having moving means to pick up and redeposit the particles of the separating medium.

This subclass is indented under subclass 271. Apparatus in which the rehabilitation means is rotatable about a stationary axis.

This subclass is indented under subclass 271. Apparatus which is provided with moving means for introducing a fluid to the bed.

SEE OR SEARCH THIS CLASS, SUBCLASS:
274 for nonsurface traversing means to apply gas to a bed.

This subclass is indented under subclass 269. Apparatus comprising means to introduce gas into the separating medium.

SEE OR SEARCH THIS CLASS, SUBCLASS:
198.1 for a separator with means to add a treating fluid, particularly subclasses 220+ for a separator with submerged fluid inlet.

This subclass is indented under subclass 269. Apparatus including means for passing a fluid through the medium in a direction of flow during separation.

SEE OR SEARCH THIS CLASS, SUBCLASS:
411 425 and 427, for similar apparatus in another type of filter.

This subclass is indented under subclass 275. Apparatus in which mechanical means is provided for agitating the bed or removing residue therefrom.

SEE OR SEARCH THIS CLASS, SUBCLASS:
273 for apparatus provided with a movable imbedded fluid distributor which functions as an agitator as well as a distributor.

This subclass is indented under subclass 275. Apparatus in which flow of fluid is controlled by a flow controller external of the casing.

SEE OR SEARCH THIS CLASS, SUBCLASS:
190 for external supply for regenerating medium combinations.
418 for a filter with a flow controller.

This subclass is indented under subclass 277. Apparatus in which a single valve controls communication with three or more flow lines.

SEE OR SEARCH THIS CLASS, SUBCLASS:
424 for a filter with a multiway valve.

SEE OR SEARCH CLASS:
137, Fluid Handling, 625 for multiway valves, per se.

This subclass is indented under subclass 275. Apparatus having a stationary fluid distributor extending into the bed.

SEE OR SEARCH THIS CLASS, SUBCLASS:
289 and 291+, for another particulate bed and a fluid distributor.

This subclass is indented under subclass 269. Apparatus in which means in provided for agitating the bed.

SEE OR SEARCH THIS CLASS, SUBCLASS:
271 for apparatus including bed surface traversing means which may also function as an agitator.
276 for a particulate bed separator with backwash means and agitator.
407 for other types of filters with residue remover or agitators.

This subclass is indented under subclass 269. Apparatus wherein a closed casing which holds particulate material is provided with an opening through which the separatory material may be reached, or through which solid regenerating material may be inserted.

SEE OR SEARCH THIS CLASS, SUBCLASS:
268 for gravity flow of particulate material in a separator.

This subclass is indented under subclass 263. Apparatus in which separatory material is encased in a magazine type holder or container.

SEE OR SEARCH THIS CLASS, SUBCLASS:
237 for handle assembly means.
465 for a separator provided with handles for draining.
470 for a handled filter.
484 for a shaped filter element with a foraminous container or sheath.

This subclass is indented under subclass 263. Apparatus comprising plural beds separated by and each contacting pervious means therebetween.

SEE OR SEARCH THIS CLASS, SUBCLASS:
266 for a particulate type separator combined with a spaced nonparticulate separating means.

This subclass is indented under subclass 263. Apparatus which comprises a plurality of beds of particulate material which are spaced from each other.

SEE OR SEARCH THIS CLASS, SUBCLASS:
266 for spaced particulate and nonparticulate type separators.
283 for a pervious separator which contacts and is between beds.
314 for spaced diverse filters.

This subclass is indented under subclass 263. Apparatus provided with at least one baffle completely or partially embedded in the particulate material.

This subclass is indented under subclass 285. Apparatus in which the baffle extends vertically.

This subclass is indented under subclass 263. Apparatus wherein the separatory material is confined within a container which is imperforate except for fluid conduit openings or access openings closed in normal operation.

SEE OR SEARCH THIS CLASS, SUBCLASS:
435 for fixed filter mediums within a flow line connected closed casing.

This subclass is indented under subclass 287. Apparatus in which all the inlets and outlets to the casing are located at the same end of the casing, one communicating with the bed by means of a conduit surrounded by the bed.

SEE OR SEARCH THIS CLASS, SUBCLASS:
439 for a nonparticulate type filter having similar structure.

This subclass is indented under subclass 287. Apparatus which comprises particular means for introducing the untreated liquid to the bed of separatory material, particular means for collecting treated liquid from the bed of separatory material, or particular strainer means within the casing.

This subclass is indented under subclass 263. Apparatus having a bed comprising a plurality of layers of particulate
material which are in contact with each other.

SEE OR SEARCH THIS CLASS, SUBCLASS:
283 for a pervious divider between and contacting the beds.
284 for similar apparatus in which the beds are spaced from each other.
286 for vertical layers.

This subclass is indented under subclass 263. Apparatus comprising particular means for introducing liquid into a bed of separating material, particular means for removing liquid from a bed of separating material, or particular strainer means within the casing.

SEE OR SEARCH THIS CLASS, SUBCLASS:
172 for separators ancillary to a storage tank.
289 for apparatus of this type which is within a flow line or flow line connected closed casing.

SEE OR SEARCH CLASS:
405, Hydraulic and Earth Engineering, subclass 36 for fluid distributing or collecting apparatus buried in the earth.

This subclass is indented under subclass 291. Apparatus in which the liquid distributing means is provided with (1) an imperforate cap or hood extending around or over it, or (2) caps or hoods over openings in the distributor.

SEE OR SEARCH THIS CLASS, SUBCLASS:
118 for a sand valve, i.e., nonclosing check valve associated with a sand bed.
456 for a filter with prefilt flow director or distributor.

This subclass is indented under subclass 291. Apparatus wherein the bed retainer comprises a pervious floor.

This subclass is indented under the class definition. Apparatus having plural separation means identifiable as separate units, (1) of different kinds, or (2) of the same kind but differing in shape or other structure other than different mesh size.

SEE OR SEARCH THIS CLASS, SUBCLASS:
124 for float control between two separators.
132 for a fluid pressure responsive by-pass and an additional separator.
142 for plural units operated by a program actuator.
151 for gas-liquid surface contact means and a separator.
155 for plural or diverse flumescreens.
182 for a heater or heat exchanger and diverse separators.
188 for a liquid treater and gas separator.
189 for plural chambers with movement of granules therebetween.
195.1 for recirculation between serially connected distinct treating or storage units.
200 for plural distinct separators and means to add a treating material.
223 for a magnetic and another separator.
252 for serially connected distinct treating units with or without a storage unit.
263 particularly subclasses 265, 266 and 284, for particulate bed type separators.
322 for plural distinct separators of the same kind.
483 particularly subclasses 488+ for single filter units formed by contacting filter mediums.
521 for superposed compartment gravitational separators.
663 for processes of ion exchange or sorption with preliminary separation.
806 for plural separating processes.

SEE OR SEARCH CLASS:
209, Classifying, Separating, and Assorting Solids, 12.1 for combined classifying, separating and assorting of solids.

This subclass is indented under subclass 294. Apparatus in which at least one of the diverse distinct separators is a filter.

This subclass is indented under subclass 295. Apparatus in which a separating medium comprises a liquid.

SEE OR SEARCH THIS CLASS, SUBCLASS:
511 for a single operation apparatus using liquid as a separating medium.
633 and 634+, for separating processes involving extraction from a liquid by solvent or solute.

This subclass is indented under subclass 295. Apparatus in which there is means to give the filter medium motion during the filtering operation.

SEE OR SEARCH THIS CLASS, SUBCLASS:
359 for movable medium filters, per se.

This subclass is indented under subclass 295. Apparatus having driven mechanical means to remove residue or sediment.

SEE OR SEARCH THIS CLASS, SUBCLASS:
390 for a moving filter medium and a residue remover.
407 for a fixed filter mdedum and a residue remover.
523 for a gravitational separator and a mechanical sediment mover.

This subclass is indented under subclass 295. Apparatus including a feature depending upon the different specific gravities of constituents of a liquid mixture for removing a constituent or trapping it in a recess.

SEE OR SEARCH THIS CLASS, SUBCLASS:
248 for drip or overflow catchers or means for receiving the contents of a filter unit when the casing is opened.

This subclass is indented under subclass 299. Apparatus in which the liquid is passed through (1) at least two filter media, a constituent trap being positioned therebetween, or (2) at least two constituent traps with a filter medium therebetween.

This subclass is indented under subclass 300. Apparatus in which at least two constituent traps are provided.

This subclass is indented under subclass 299. Apparatus provided with a valve in a flow line upstream of the separating means.

SEE OR SEARCH THIS CLASS, SUBCLASS:
136 for a check valve upstream of a separator.

This subclass is indented under subclass 299. Apparatus having a valve arranged to isolate a sediment chamber from a filter unit.

SEE OR SEARCH THIS CLASS, SUBCLASS:
418 for a filter with a flow controller.

This subclass is indented under subclass 299. Apparatus in which there is a spiral or convolute baffle or tangential liquid inlet to give the liquid a whirling motion.

SEE OR SEARCH THIS CLASS, SUBCLASS:
512.1 for a gravitational separator having tangential flow or centrifugal fluid action.

This subclass is indented under subclass 299. Apparatus provided with a baffle member to deflect liquid entering a sediment chamber or a baffle within a sediment chamber to catch sediment or quiet flow.

SEE OR SEARCH THIS CLASS, SUBCLASS:
304 for a sediment trap and filter with spiral or convolute baffle means or a tangential inlet.

This subclass is indented under subclass 305. Apparatus in which the baffle deflects prefilt from the filtering medium.

SEE OR SEARCH THIS CLASS, SUBCLASS:
456 for a filter with prefilt a flow distributor or diverter.

This subclass is indented under subclass 299. Apparatus in which the sediment removing, trapping or removing feature is downstream of the filter, to remove sediment from the filtrate.

SEE OR SEARCH THIS CLASS, SUBCLASS:
300 for alternate traps and filters.

This subclass is indented under subclass 299. Apparatus in which a sediment trap directly communicates with the interior of a tubular filter element.

This subclass is indented under subclass 308. Apparatus in which the filter element and the sediment chamber means are directly attached to each other.

SEE OR SEARCH THIS CLASS, SUBCLASS:
454 for a filter within a flow line connected casing which filter element is attached to a casing closure.

This subclass is indented under subclass 299. Apparatus in
which the liquid flows generally axially through a conduit containing the filter medium and there is means communicating with the sediment trap, which extends laterally of the axis of the conduit.

SEE OR SEARCH THIS CLASS, SUBCLASS:
447 for a laterally removable filter element.

This subclass is indented under subclass 299. Apparatus in which entering liquid flows downwardly and then passes through the filter medium in an upward direction.

SEE OR SEARCH THIS CLASS, SUBCLASS:
305 for filter and constituent trap means with a baffle preceding or within the sediment trap.
456 for a filter with a prefilt flow distributor or diverter.

This subclass is indented under subclass 299. Apparatus provided with means discharging sediment.

SEE OR SEARCH THIS CLASS, SUBCLASS:
422 for a closed casing filter and a variable flow controller which casing has plural outlets for flushing the casing or diverting prefilt around the filter medium.
433.1 for a filter in a casing having filtered and unfiltered passages.
533 for a gravitational separator with a closure or valve controlled discharge.

This subclass is indented under subclass 312. Apparatus in which the drain means is controlled by a valve.

SEE OR SEARCH THIS CLASS, SUBCLASS:
109 for automatic discharge of treated material.

This subclass is indented under subclass 295. Apparatus which comprises a plurality of isolated filters or filter elements abutting along a surface to enclose an empty space.

SEE OR SEARCH THIS CLASS, SUBCLASS:
323 for plural distinct similar filters.

This subclass is indented under subclass 314. Apparatus wherein one of the filters surrounds the other.

This subclass is indented under subclass 314. Apparatus wherein one filter is arranged in such a manner that entering liquid contacts the filter before contacting any part of the casing, or leaving liquid once having contacted the filter, does not contact the casing.

SEE OR SEARCH THIS CLASS, SUBCLASS:
335 for plural similar filters arranged for series prefilt flow.
338 and 342, for plural distinct similar filter elements arranged one within another.
464 for a portable receptacle draining filter.

This subclass is indented under subclass 314. Apparatus in which one or more of the filters include loose or flaccid
nonparticulate material.

SEE OR SEARCH THIS CLASS, SUBCLASS:
263 for particulate material type separators, particularly subclass 266 for particulate and spaced nonparticulate separators.
484 for filter medium within a foraminous container or sheath.
496 for shaped bound, fused or matted filter mediums.
500 for filter materials.

This subclass is indented under subclass 314. Apparatus in which the separate filters are of such shapes that they cannot be nested or superimposed.

This subclass is indented under subclass 294. Apparatus in which there is a mechanical agitator to impel liquid to break up, remove or prevent scum.

SEE OR SEARCH THIS CLASS, SUBCLASS:
198 particularly subclasses 207+ and 219, for a separator with means to add material.
407 for a filter having a fixed medium combined with an agitator.

This subclass is indented under subclass 294. Apparatus in which there is a baffle perpendicular to the direction of liquid flow.

SEE OR SEARCH THIS CLASS, SUBCLASS:
348 for apparatus which uses a semipermable septum which does not provide for continuous streams on both sides of the
septum.
513 for a gravitational separator.

CASING DIVIDED BY MEMBRANE INTO SECTIONS HAVING INLET(S) AND/OR OUTLET(S):
This subclass is indented under the class definition. Apparatus comprising a casing sealingly divided by a barrier comprising a semipermeable membrane into at least two sections, each section having means providing liquid inlet and/or outlet provided by said semipermeable membrane.

SEE OR SEARCH CLASS:
604, Surgery, subclass 507 for methods of introducing material into or removing it from the human vasculature system

Membrane secured with adhesive of specified composition:
This subclass is indented under subclass 321.6. Apparatus including an adhesive of specified composition securing at least one membrane.

Antithrombogenic membrane:
This subclass is indented under subclass 321.6. Apparatus including at least one membrane having at least a portion thereof modified (e.g., by chemical treatment or ionizing radiation) to be antithrombogenic.

Rotating mechanical agitator adjacent membrane:
This subclass is indented under subclass 321.6. Apparatus including a rotating mechanical agitator (e.g., stirrer) adjacent a membrane.

Plural diverse structured membranes within a single casing:
This subclass is indented under subclass 321.6. Apparatus including plural diverse structured membranes (e.g., stirrer) adjacent a membrane.

SEE OR SEARCH THIS CLASS, SUBCLASS:
641 for processes utilizing plural diverse membranes.

Permeated liquid quantity measurement or control:
This subclass is indented under subclass 321.6. Apparatus including means to measure and/or control a quantity of liquid which has permeated through a membrane (e.g., ultraflitrate, dialysate, etc.).

SEE OR SEARCH THIS CLASS, SUBCLASS:
929 for hemoultrafiltrate volume measurement or control processes.

Energy recovery from treated liquid:
This subclass is indented under subclass 321.6. Apparatus including means for energy recovery (e.g., turbine, flow work exchanger, etc.), from a treated liquid.

Membrane movement during purification:
This subclass is indented under subclass 321.6. Apparatus including means causing membrane movement during liquid purification.

Nontranslatory rotary:
This subclass is indented under subclass 321.67. Apparatus wherein said means causes nontranslatory rotary membrane movement during liquid purification.

With membrane cleaning or sterilizing means (other than by filter movement or rotating agitator):
This subclass is indented under subclass 321.6. Apparatus including means providing membrane cleaning (removing accumulated undesired material) or sterilizing (destroying a pathogenic micro-organism), other than by a rotating mechanical agitator or membrane movement.

SEE OR SEARCH THIS CLASS, SUBCLASS:
321.63 and 321.67, for membrane cleaning apparatus including a rotating mechanical agitator or membrane movement.
636 for processes of cleaning or sterilizing.

Solid cleaning material (e.g., balls):
This subclass is indented under subclass 321.69. Apparatus wherein said means providing membrane cleaning or sterilizing includes a plurality of solid discrete object other than a rotating mechanical agitator, e.g., particles, granules, sponge balls, beads, etc., and means for moving said object, adjacent to and/or in contact with, a membrane, for cleaning or sterilizing said membrane.

SEE OR SEARCH THIS CLASS, SUBCLASS:
321.63 for apparatus including a rotating mechanical agitator.

Dialyzer with dialysate proportioning means:
This subclass is indented under subclass 321.6. Apparatus including a dialyzer and means for proportioning dialysate fed to said dialyzer.

Each section having inlet(s) and outlet(s):
This subclass is indented under subclass 321.6. Apparatus further comprising each said section having at least one
means providing liquid inlet and at least one means providing liquid outlet.

Noncoiled nonannular cross section tube:
This subclass is indented under subclass 321.72. Apparatus wherein at least on e membrane is, (a) generally tubular, (b) noncylindrical in defining a cross section (said cross section being taken perpendicularly to the central axis of the tube) which is nonannular (e.g., inner and/or outer surface(s) define noncircular cross section), and (c) not coiled.
(1) Note. A coiled flatted membrane tube is provided for in subclasses 321.74 and 321.83.

Coiled membrane:
This subclass is indented under subclass 321.72. Apparatus said semipermeable membrane is a strip or flattened tube (i.e., is noncyclindrical) which is spirally coiled (e.g., including either a planar spiral or a helical spiral).

Planar membrane:
This subclass is indented under subclass 321.72. Apparatus wherein said semipermeable membrane is in an essentially planar configuration.

Spiral flow:
This subclass is indented under subclass 321.75. Apparatus including means providing spiral liquid flow (moving essentially in a plane around a center with increasing or decreasing distance from said center) adjacent a membrane(s).

Pleated membrane:
This subclass is indented under subclass 321.72. Apparatus wherein said semipermeable membrane is pleated (i.e., folded back and forth).

Cylindrical membrane:
This subclass is indented under subclass 321.72. Apparatus wherein said semipermeable membrane comprises at least one hollow generally cylindrical tube.

Plural cylindrical membrane all connected for parallel flow:
This subclass is indented under subclass 321.78. Apparatus including plural cylindrical semipermeable membrane tubes all or which, are connected for parallel flow therethrough (i.e., each said tube has, a first end directly communicating with a first end directly communicating with a first header, and a second end directly communication with a second Header), and are within a single casing.

All cylindrical membranes are parallel:
This subclass is indented under subclass 321.79. Apparatus wherein all said plural cylindrical semipermeable membrane tubes are parallel with respect to each other.

With embedded baffle:
This subclass is indented under subclass 321.8. Apparatus wherein a baffle which is a solid material, which serves as a flow restrictor, diverter or distributor, is embedded between said plural parallel cylindrical semipermeable membrane tubes such that, a straight line drown from an exterior active surface (e.g., a membranae tube sheet, etc.), or any one of said tubes, perpendicular to a longitudinal axis of that tube, to an exterior active surface of any other of said tubes, intersects said baffle.

Noncoiled nonannular cross section tube:
This subclass is indented under subclass 321.6. Apparatus wherein at least one membrane is, (a) generally tubular, (b) noncylindrical in defining a cross section (said cross section being taken perpendicularly to the central axis of the tube) which is nonannular (e.g., inner and/or outer surface(s) define noncircular cross section, and (c) not coiled.
(1) Note. A coiled flattened membrane tube is provided for in subclasses 321.74 and 321.83.

Coiled membrane:
This subclass is indented under subclass 321.6. Apparatus wherein said semipermeable membrane is a strip or flattened tube (i.e., is noncylindrical), which is spirally coiled (e.g., including either a planar spiral or a helical spiral).

Planar membrane:
This subclass is indented under subclass 321.6. Apparatus wherein said semipermeable membrane is in an essentially planar configuration.

Spiral flow:
This subclass is indented under subclass 321.84. Apparatus including means providing spiral liquid flow (moving essentially in a plane around a center with increasing or decreasing distance from said center adjacent a membrane(s).

Pleated membrane:
This subclass is indented under subclass 321.6. Apparatus wherein said semipermeable membrane is pleated, i.e., folded
back and forth.

Cylindrical membrane:
This subclass is indented under subclass 321.6. Apparatus wherein said semipermeable membrane comprises at least on hollow, generally cylindrical tube.

Plural cylindrical membranes all connected for parallel flow:
This subclass is indented under subclass 321.87. Apparatus including plural cylindrical semipermeable membrane tubes all of which, are connected for parallel flow therethrough (i.e., each said tube has a first end directly communication with a first header, and a second end directly communication with a second header), and are within a single ceasing.

All cylindrical membranes are parallel:
This subclass is indented under subclass 321.88. Apparatus wherein all said plural cylindrical semipermeable membrane tubes are parallel with respect to each other.

With embedded baffle:
This subclass is indented under subclass 321.89. Apparatus wherein a baffle which is a solid material, which serves as a flow restrictor, diverter or distributor, is embedded between said plural parrallel cylindrical semipermeable membranse tubes such that, a straight linek drawn fro an exterior active surface (e.g., a membrane tube surface not covered by casting resin, tube sheet, etc.) of any one of said tubes perpendicular to a lingitudinal axis of that tube, to an exterior active surface of any other of said tubes, intersects said baffle.

This subclass is indented under the class definition. Apparatus comprising two or more distinct separators each of which treats a portion of a liquid mixture.

SEE OR SEARCH THIS CLASS, SUBCLASS:
252 for serially connected distinct treating units with or without storage units.
294 for diverse distinct separators.
488 for superimposed contacting filter mediums forming a single element even though defined as differing in kind.
521 for a gravitational separator with superposed compartments.

Filters:
This subclass is indented under subclass 322. Apparatus in which there are plural distinct filter units.

SEE OR SEARCH THIS CLASS, SUBCLASS:
314 for diverse types of filters in a single unit.

Tublar:
This subclass is indented under subclass 323.1. Apparatus tubelike in form with filtration through the perpendicular axis of the tube.

This subclass is indented under subclass 323.1. Apparatus which are movable for material treating purposes.

SEE OR SEARCH THIS CLASS, SUBCLASS:
359 for a movable filter which may comprise compartments or sections abutted to form a single effective surface.

This subclass is indented under subclass 324. Apparatus in which each rotates about an individual axis and also moves about another axis, the construction being such that rotation about both axes are or can be continuous during operation.

SEE OR SEARCH THIS CLASS, SUBCLASS:
370 for a centrifugal extractor wherein the filter medium has plural motions about a fixed point.

This subclass is indented under subclass 324. Apparatus comprising plural rotary filter drums arranged on parallel axes which drums are of the type in which prefilt contacts the outer periphery of both drums simultaneously and the filtrate flows to their interiors in parallel.

This subclass is indented under subclass 324. Apparatus with plural cleaning means.

SEE OR SEARCH THIS CLASS, SUBCLASS:
330 for plural moving filter units connected for group operation.
334 for plural fixed units and alternating cleaners.

This subclass is indented under subclass 324. Apparatus connected by hinges or mounted on parallel pivots so that they can be partially rotated to dump the cake (residue).

SEE OR SEARCH THIS CLASS, SUBCLASS:
370 for a centrifugal extractor wherein the basket is made up of plural sections which are pivotally mounted for
discharging the portion of the residue thereon.
385 for a filter unit having plural motions.

This subclass is indented under subclass 324. Apparatus in which at least one filter and its support moves with respect to another, usually for cleaning while at least one remains in filtering service.

SEE OR SEARCH THIS CLASS, SUBCLASS:
232 particularly subclasses 237+ for a separator with repair or assembly means for removal of a filter from its casing.
328 for filters comprising pivotally mounted sections.
341 for parallel units individually controlled, so that a selected unit can be removed.

This subclass is indented under subclass 324. Apparatus having means connecting them so that they move together as a connected group.

SEE OR SEARCH THIS CLASS, SUBCLASS:
359 for moving filter medium types in which the medium is continuous or comprises abutting filtering sections forming in effect a continuous medium except for separating strips or partitions.

This subclass is indented under subclass 330. Apparatus comprising spaced wall type filter elements, e.g., multiple hollow circular leaves.

SEE OR SEARCH THIS CLASS, SUBCLASS:
327 for alternating moving elements and cleaning means.
486 for similar elements, per se.

This subclass is indented under subclass 323. Apparatus in which there is means for removing residue or for agitating the liquid.

SEE OR SEARCH THIS CLASS, SUBCLASS:
298 for diverse separators having mechanical residue or sediment removers.
407 for a single filter having a residue remover or agitator.

Backwash of blowback:
This subclass is indented under subclass 332. Apparatus having means for causing a reverse flow through the filter medium that is out of service.

Sequential backwash:
This subclass is indented under subclass 333.01. Apparatus having means to successively clean the filter units.

This subclass is indented under subclass 332. Apparatus in which the filter units and cleaning means are arranged in alternation.

This subclass is indented under subclass 323.1. Apparatus which are in series.

SEE OR SEARCH THIS CLASS, SUBCLASS:
252 for serially connected distinct treating units.
300 for alternate traps and filters in series.
314 for spaced diverse filters.
489 for abutted or superimposed members forming a single filter element, arranged for series flow through the members.

This subclass is indented under subclass 335. Apparatus in which the flow of fluid is in a tortuous or zig-zag path.

SEE OR SEARCH THIS CLASS, SUBCLASS:
285 for baffles imbedded in a particulate bed.

This subclass is indented under subclass 335. Apparatus arranged in superimposed or nested relation, each unit being removable from the other.

SEE OR SEARCH THIS CLASS, SUBCLASS:
315 for diverse concentric spaced filters.
342 for concentric filter elements arranged for parallel flow.

This subclass is indented under subclass 337. Apparatus in which the nested units are concentric filter elements.

This subclass is indented under subclass 335. Apparatus comprising a frame or casing having inwardly extending flanges or protuberances supporting the filter elements.

SEE OR SEARCH THIS CLASS, SUBCLASS:
451 for a filter element supported within a casing by an internal fixed shoulder.

This subclass is indented under subclass 323.1. Apparatus having means for interrupting flow to at least one filter unit while another remains in service, said filters being in parallel.

SEE OR SEARCH THIS CLASS, SUBCLASS:
418 for a single filter with a flow controller.

This subclass is indented under subclass 340. Apparatus in which there is provision for using different filter elements with a common receiver and each filter element has an individual flow control means.

SEE OR SEARCH THIS CLASS, SUBCLASS:
329 for relatively movable filters which may act to cut off flow.

This subclass is indented under subclass 323.1. Apparatus wherein the filter units are arranged one within another.

SEE OR SEARCH THIS CLASS, SUBCLASS:
315 for spaced diverse filters, one within another.
337 for nested filter units arranged for series prefilt flow.

This subclass is indented under subclass 323.1. Apparatus in which the units alternate with liquid receivers, alternate receivers acting respectively as liquid inlet and discharge means, at least one of a pair of liquid receivers separating one filter medium from another and contacting the separated filter mediums on opposite faces.

SEE OR SEARCH THIS CLASS, SUBCLASS:
417 for similar devices in which the alternate liquid receivers are located within a continuous body of filter medium.

This subclass is indented under subclass 323.1. Apparatus in which each filter unit comprises a filter medium and an imperforate pan-like liquid receiver substantially coextensive with the filter medium.

SEE OR SEARCH THIS CLASS, SUBCLASS:
224 for a sectional chamber press type filter.
492 for stacked dissimilar elements, the entire stack forming a single unit.

This subclass is indented under subclass 323.1. Apparatus in which the units are radially arranged or which are connected to means extending radially from a central header.

This subclass is indented under subclass 323.1. Apparatus in which the units each comprise a filter medium enclosing a space, the filter medium having separate or distinct walls.

SEE OR SEARCH THIS CLASS, SUBCLASS:
331 for similar structure among movable elements.
486 for a spaced wall type filter unit.
492 for filter elements divided into alternate prefilt and filtrate spaces by alternately arranged dissimilar elements.

This subclass is indented under subclass 346. Apparatus in which there is a header extending centrally of the group of spaced wall type filter elements.

This subclass is indented under the class definition. Apparatus in which constituents of a prefilt (usually solids and liquid) are separated by passing the prefilt through a medium having openings which retain at least one constituent.

SEE OR SEARCH CLASS:
4, Baths, Closets, Sinks, and Spittoons, subclass 286 for strainers specialized for that class.
55, Gas Separation, appropriate subclasses beginning with subclass 474 for gas filters.
166, Wells, 227 for screens peculiar to wells.
209, Classifying, Separating, and Assorting Solids, 233 for sifters for solid material.

This subclass is indented under subclass 348. Apparatus provided with means dampening pulsations in liquid flow or for trapping a gas, usually air.

SEE OR SEARCH THIS CLASS, SUBCLASS:
410 for a device which traps a gas and then releases it to blowback a filter medium.

This subclass is indented under subclass 348. Apparatus in which a filter medium is enclosed by a receptacle and provided with adjustable or movable means to compress the filtering material.

SEE OR SEARCH THIS CLASS, SUBCLASS:
226 for a sectional pressure type filter and porous filler.

This subclass is indented under subclass 350. Apparatus including means external of a closed receptacle to actuate or adjust the means which compresses the filter medium.

This subclass is indented under subclass 350. Apparatus wherein the means to compress comprises a spring encased by the receptacle.

This subclass is indented under subclass 348. Apparatus in which there is a cleaning means, as loose abrading particles or wiping elements, which are free to move, (not attached to a retaining means).

SEE OR SEARCH THIS CLASS, SUBCLASS:
263 for a filter having loose material acting as a filter medium.

This subclass is indented under subclass 348. Apparatus in which either the filter medium, residue remover or agitator is moved by the fluid being treated.

SEE OR SEARCH THIS CLASS, SUBCLASS:
97 for fluid responsive controls, particularly subclasses 121+ for float responsive controls.
242 for a float supported separator.
396 for a movable medium and solid cleaning member which may be forced against the medium by fluid pressure.

This subclass is indented under subclass 354. Apparatus in which the only element moved by the fluid is a residue remover.

This subclass is indented under subclass 354. Apparatus in which the filter element is so mounted or specially constructed as to be flexed or compressed by movement of liquid therethrough.

SEE OR SEARCH THIS CLASS, SUBCLASS:
359 for means to flex an anchored filter.
391 for moving filter mediums and blow back means in which flexing may occur incidental to such operation.

This subclass is indented under subclass 348. Apparatus in which a cleaning member is extendable between filter mediums or through openings in the filter medium.

SEE OR SEARCH THIS CLASS, SUBCLASS:
334 for distinct filters alternating with residue removers.
396 for a movable filter and an adjacent cleaner.

This subclass is indented under subclass 348. Apparatus in which there is an imperforate drum having a filter element extending across a segment, covering an arc, or covering either or both end walls of the drum.

SEE OR SEARCH THIS CLASS, SUBCLASS:
399 for another type of movable sealed casing enclosing a filter medium.

This subclass is indented under subclass 348. Apparatus in which the filter medium is capable of movement for treatment purposes.

SEE OR SEARCH THIS CLASS, SUBCLASS:
107 for flow fluid pressure or material level responsive movement of a filter medium.
122 for float control of a movable separator.
154 for a flume type movable filter.
178 for a movable separator with a heat exchanger.
189 and 263+, particularly subclasses 267 and 268 for particulate material type separators.
232 for separators combined with handling means.
297 for diverse distinct separators including a movable filter medium.
324 for plural movable separating elements.
354 for motion due to flowing fluids.
447 for a closed casing having provision for laterial removal of the filter element.
680 for processes involving movement of filter medium.

Centrifugal extractor:
This subclass is indented under subclass 359. Apparatus wherein structure including the filter medium is particularly adapted for rapid movement about an axis of rotation.

SEE OR SEARCH THIS CLASS, SUBCLASS:
144 for a filter automatically controlled in response to vibration.

SEE OR SEARCH CLASS:
34, Drying and Gas or Vapor Contact With Solids, subclass 58 for a centrifugal filter combined with a distinct and separate drying unit or for rotary work holders acting as driers, and see search notes for other devices involving the use of centrifugal force.
57, Textiles: Spinning, Twisting, and Twining, 76 for centrifugal pots and guides.
68, Textiles: Fluid Treating Apparatus, 23 for washing machines having centrifugal extractor features.
118, Coating Apparatus, 52 for centrifugal coating apparatus.
127, Sugar, Starch, and Carbohydrates, subclass 19 for sugar treatment including purging and molding centrifugals.
162, Paper Making and Fiber Liberation, subclass 384 for paper making apparatus utilizing centrifugal force to dewater the slurry on the mold surface.
192, Clutches and Power-Stop Control, subclass 136 for a cover latch control interlocked with driving mechanism for a centrifugal extractor.
494, Imperforate Bowl: Centrifugal Separators, appropriate subclasses, for apparatus for breaking up a mixture of fluids or fluent substances into two or more components by centrifuging within a generally solid-walled, receptacle-like member, and see especially subclass 36 for a separator of that class provided with filtering means.

With inward flow of feed component:
This subclass is indented under subclass 360.1. Apparatus wherein at least a portion of the medium moves in an inward
direction.

This subclass is indented under subclass 360.1. Apparatus in which means are provided for individually supporting articles for the removal of liquid therefrom, e.g., honey extractors.

SEE OR SEARCH CLASS:
34, Drying and Gas or Vapor Contact With Solids, subclass 58 for centrifugal devices for removing liquid from articles, e.g., honey from combs not having any means for separating by filtration or straining.

This subclass is indented under subclass 361. Apparatus in which the position of the article supporting means is reversible relative to the axis of rotation to alternaterly present opposite sides of the article away from such axis.

This subclass is indented under subclass 360.1. Apparatus wherein adjustable means is provided to position the center of gravity of the structure on the geometric axis of rotation.

SEE OR SEARCH THIS CLASS, SUBCLASS:
145 for variable rotation condition responsive control.

SEE OR SEARCH CLASS:
74, Machine Element or Mechanism, 572 for flywheels or rotors with balancing or vibration dampening means defining no features of separator construction.

This subclass is indented under subclass 360.1. Apparatus wherein the filter medium is mounted on a shaft and is enclosed by a nonrotating casing, both the rotating structure and casing being mounted for gyratory movement as a unit.

SEE OR SEARCH CLASS:
248, Supports, 637 for machinery supports.

This subclass is indented under subclass 360.1. Apparatus wherein the filter medium is mounted upon a rotating shaft, both the filter medium and shaft being mounted for gyratory movement as a unit.

This subclass is indented under subclass 365. Apparatus wherein the mounting is above the filter medium.

This subclass is indented under subclass 360.1. Apparatus wherein the filter medium is gyratorily supported.

SEE OR SEARCH THIS CLASS, SUBCLASS:
325 for plural centrifugal extractors with planetary motion.

This subclass is indented under subclass 360.1. Apparatus with means for slowing or stopping rotation.

SEE OR SEARCH CLASS:
192, Clutches and Power-Stop Control, 215 for brake and power transmission control of general utility.

This subclass is indented under subclass 360.1. Apparatus including structure to discharge residue.

This subclass is indented under subclass 369. Apparatus comprising means giving the filter medium, in whole or in part, an additional motion.

SEE OR SEARCH THIS CLASS, SUBCLASS:
232 for means assembling and disassembling a filter, particularly subclasses 237+ for a filter with hoist or handle means.

This subclass is indented under subclass 369. Apparatus comprising a variable controller for flow of residue.

SEE OR SEARCH THIS CLASS, SUBCLASS:
418 for fixed filter and flow controller and see the search notes thereunder.

This subclass is indented under subclass 369. Apparatus in which discharge of the residue is effected or controlled by means engaging it, e.g., doctor blades.

SEE OR SEARCH CLASS:
15, Brushing, Scrubbing, and General Cleaning, subclass 256.5 for a moving surface scraper, wiper or brush of general application.

This subclass is indented under subclass 372. Apparatus in which the residue engaging means is stationarily mounted.

This subclass is indented under subclass 372. Apparatus in which the residue engaging means is rotatably mounted with respect to the filter medium.

This subclass is indented under subclass 374. Apparatus in which the residue engaging means is pivotably mounted.

This subclass is indented under subclass 372. Apparatus in which the residue engaging means is axially reciprocable parallel to the axis of rotation.

This subclass is indented under subclass 360.1. Apparatus within the rotating filter medium for distributing the incoming material feed.

SEE OR SEARCH THIS CLASS, SUBCLASS:
213 and 214, for a moving filter element having a movable distributor for introducing a treating material to the interior thereof.

This subclass is indented under subclass 360.1. Apparatus including filtrate receiving means provided with a plurality of separate outlets.

SEE OR SEARCH THIS CLASS, SUBCLASS:
215 for similar structure having means to add a treating material within the separator.

This subclass is indented under subclass 360.1. Apparatus in which the separating structure rotates about an upright axis and in which the filtrate discharge therefrom is restricted to a zone at or adjacent the top thereof, combined with a filtrate receiving trough disposed above the bottom of the rotating structure and surrounding the filtrate discharge.

Rotating element construction:
This subclass is indented under subclass 360.1. Apparatus comprising the rotating separator structure, per se.

SEE OR SEARCH THIS CLASS, SUBCLASS:
369 for a tapered basket for discharging residue.
483 particularly subclass 497 for a cylindrical or conical filter medium of general application.

SEE OR SEARCH CLASS:
220, Receptacles, 200 for a container cover in which no special features peculiar to rotatable extractor operation are defined.

Laundry:
This subclass is indented under subclass 380.1. Apparatus for washing or drying clothes.

Horizontal axis:
This subclass is indented under subclass 380.1. Apparatus which rotates around horizontal axis.

This subclass is indented under subclass 380.1. Apparatus including inwardly extending partitions dividing the interior of the separating structure into compartments.

SEE OR SEARCH CLASS:
34, Drying and Gas or Vapor Contact With Solids, subclass 109 for a compartmented drier drum.
68, Textiles: Fluid Treating Apparatus, subclass 143 for a compartmented tumbling and washing drum.

This subclass is indented under subclass 380.1. Apparatus in which the separating structure rotates about an upright axis, and its filtrate discharge is restricted to a zone at or adjacent the top.

SEE OR SEARCH THIS CLASS, SUBCLASS:
246 for a portable receptacle having a cover limited as to its opening movement.
379 for a filtrate receiving trough at or adjacent the top of the separating structure.

This subclass is indented under subclass 359. Apparatus having separate agitating means.

SEE OR SEARCH THIS CLASS, SUBCLASS:
167 for a structural closed circulating system.
194 for recirculation means.
407 for a fixed filter medium and an agitator or a cleaner, and see the search notes thereto.

This subclass is indented under subclass 359. Apparatus comprising means for vibrating the filter medium which is moving continuously in one direction, e.g., belt or drum.

SEE OR SEARCH THIS CLASS, SUBCLASS:
388 for other types of vibrating movable filters.

This subclass is indented under subclass 359. Apparatus in which the filter unit has more than one motion, e.g., rotation and translation or rotation on plural axes.

SEE OR SEARCH THIS CLASS, SUBCLASS:
323 for plural movable filter elements which may have plural motions.
370 for a centrifugal extractor having plural motions of the filter medium.
384 for a unidirectional motion filter and vibrator for the medium.

This subclass is indented under subclass 359. Apparatus in which there are rolls or confining members which contact the residue on the moving medium, e.g., for compacting, shielding or takeoff.

SEE OR SEARCH THIS CLASS, SUBCLASS:
401 for a belt type filter superimposed on a moving support.
402 for a drum filter.

This subclass is indented under subclass 359. Apparatus unrollable from a spool or equivalent source so as to present successive areas for the filtering operation.

This subclass is indented under subclass 359. Apparatus in which the filter medium vibrates or has motion back and forth in a plane parallel to the surface of the filtering medium during filtration.

SEE OR SEARCH THIS CLASS, SUBCLASS:
354 for a filter medium flexed by fluid flow.
384 for a vibrator acting on a unidirectional motion filter medium.
385 for a filter having plural motions.

SEE OR SEARCH CLASS:
209, Classifying, Separating, and Assorting Solids, 325, 331, 333+, and 341 for shaking sifters for solids, and subclasses 437+ for reciprocating liquid treatment stratifiers.

This subclass is indented under subclass 388. Apparatus in which the prefilt is fed in at one point of a filter medium, usually one end, and moves along it.

This subclass is indented under subclass 359. Apparatus supported by a movable valve part.

SEE OR SEARCH THIS CLASS, SUBCLASS:
385 for a filter element having at least two motions.
395 for a moving filter with cleaning means so connected to a valve that movement of the medium actuates the valve.

SEE OR SEARCH CLASS:
137, Fluid Handling, 547 for a movable strainer for gas separation combined with flow control means.

This subclass is indented under subclass 359. Apparatus having means for removing residue.

SEE OR SEARCH THIS CLASS, SUBCLASS:
107 for flow, fluid pressure or material level responsive cleaning movement of a filter medium.
158 for a movable flume stream type strainer with cleaning means.
216 for moving filter medium and means for adding a treating material.
369 for a centrifugal extractor with residue removing means.
386 for rolls or confining members which may act as residue removers.
399 for a movable casing which may clean by merely reversing the casing position.
407 for residue remover for a fixed filter medium and see the search notes.

SEE OR SEARCH CLASS:
162, Paper Making and Fiber Liberation, 274 for paper making apparatus having means to clean or condition a porous or foraminous member.

This subclass is indented under subclass 391. Apparatus having (1) a member fixed in position which contacts the filter medium or its support, or (2) a member actuating
valves attached to a moving filter medium or its support; either (1) or (2) acting to block fluid flow through part of the moving filter medium.

This subclass is indented under subclass 391. Apparatus having blowback or backwash cleaning means and another cleaning means, e.g., scraper or brush.

This subclass is indented under subclass 391. Apparatus in which the moving filter medium encloses a space and the cleaning means acts to return residue to said space.

SEE OR SEARCH THIS CLASS, SUBCLASS:
194 for recirculation.
403 for an internal feed type rotary drum filter without cleaning means.

This subclass is indented under subclass 391. Apparatus in which flow of fluids is controlled by valve means actuated by the moving medium.

SEE OR SEARCH THIS CLASS, SUBCLASS:
142 for valves connected to a moving filter medium in combination with programming means.
390 for filter medium supported by and movable with a valve member.
392 for a fixed member operating valves attached to a moving filter unit.

This subclass is indented under subclass 391. Apparatus comprising a scraper, wiper, abrader, cutter, brush or similar solid member.

SEE OR SEARCH THIS CLASS, SUBCLASS:
372 for a centrifugal extractor with a residue engaging means.
393 for a scraper, cutter or brush combined with backwash or blowback.

SEE OR SEARCH CLASS:
15, Brushing, Scrubbing, and General Cleaning, subclass 256.5 for moving surface scrapers of general application.

This subclass is indented under subclass 396. Apparatus having plural outlets from a casing for the medium.

SEE OR SEARCH THIS CLASS, SUBCLASS:
433 for divided filtered and unfiltered liquid passages and see notes thereunder.

This subclass is indented under subclass 359. Apparatus within a casing sealed except for necessary fluid inlet or outlet.

SEE OR SEARCH THIS CLASS, SUBCLASS:
267 for a trunnion mounted particulate material type separator.
358 for an imperforate drum with the medium on an arc, chord or end wall.

This subclass is indented under subclass 398. Apparatus in
which the closed casing is mounted for motion.

SEE OR SEARCH THIS CLASS, SUBCLASS:
390 for a filter medium or casing attached to a movable valve element.

SEE OR SEARCH CLASS:
422, Chemical Apparatus and Process Disinfecting, Deodorizing, Preserving, or Sterilizing, 258 and 269+ for rotary extractor or leacher.

This subclass is indented under subclass 359. Apparatus comprising a closed loop or filter elements attached to a closed loop carrier.

SEE OR SEARCH THIS CLASS, SUBCLASS:
160 for a flume stream type endless belt filter.
370 for an endless belt type filter element forming the wall of a centrifugal extractor.

SEE OR SEARCH CLASS:
162, Paper Making and Fiber Liberation, 348 for flexible endless band type mold paper making machines (e.g., Fourdrinier machines).
209, Classifying, Separating, and Assorting Solids, 307 for endless belt sifters for solids.

This subclass is indented under subclass 400. Apparatus supported on an additional moving means.

SEE OR SEARCH THIS CLASS, SUBCLASS:
386 for running strand residue removers.

This subclass is indented under subclass 359. Apparatus in the shape of a drum.

SEE OR SEARCH THIS CLASS, SUBCLASS:
161 for a revolving flume stream type filter.
174 for a movable cylindrical filter having comminuting means.
210 and 217, for a drum type separator having means to add a treating material.
326 for plural drums on parallel axes.

SEE OR SEARCH CLASS:
162, Paper Making and Fiber Liberation, 323 and 357 for cylinder mold type paper making machines.

This subclass is indented under subclass 402. Apparatus in which prefilt enters the inside of the rotating filter.

SEE OR SEARCH THIS CLASS, SUBCLASS:
394 for an internally fed rotary drum with cleaning means.

SEE OR SEARCH CLASS:
209, Classifying, Separating, and Assorting Solids, 288 for rotating drum sifters for solids.

This subclass is indented under subclass 402. Apparatus comprising an inner wall surrounded by a filter element forming an annular space divided into segments by partitions.

This subclass is indented under subclass 348. Apparatus
having moving means which receives and distributes the prefilt against a filter medium, e.g., rotary thrower.

SEE OR SEARCH THIS CLASS, SUBCLASS:
377 for an internal work distributor for a centrifugal extractor.
456 for a fixed prefilt flow distributor and diverter.

This subclass is indented under subclass 348. Apparatus in which there is means to apply a vacuum to a closed filtrate receiver with no liquid being removed to the vacuum source.

SEE OR SEARCH THIS CLASS, SUBCLASS:
416 for liquid pump, gas pressure or liquid suction source combinations.
459 for a pipe end attached filter which pipe may be a suction pipe.
481 for a filter element of the type often used with a reflux or vacuum coffee maker.

This subclass is indented under subclass 348. Apparatus having means for removing residue from the filter medium or for agitating either the prefilt or filtrate.

SEE OR SEARCH THIS CLASS, SUBCLASS:
106 for automatic filter cleaning.
159 for means to remove residue from a cleaner for a flume stream strainer.
179 for a mechanical agitator in a heat exchanger.
208 for a mechanical agitator in a reactor tank.
219 for a mechanical agitator and means to add treating material.
225 for similar structure in a sectional chamber press filter.
251 for means for cleaning the outer casing of a separator.
269 for rehabilitation means for a particulate bed separator.
298 for diverse separators having residue removing means.
319 for diverse separators having agitating means.
332 for plural separators with residue removal.
353 for a filter with free cleaning means.
345 for movement of the medium, cleaner or agitator by fluid.
791 for processes of rehabilitating filter mediums.

This subclass is indented under subclass 407. Apparatus provided with diverse residue removal or agitating means, e.g., agitators, scrapers, brushes, means to add a gas, means to blowback through the filter medium.

SEE OR SEARCH CLASS:
209, Classifying, Separating, and Assorting Solids, 379 for sifting screen cleaners.

This subclass is indented under subclass 407. Apparatus having (1) means to add a fluid to or trap a fluid within the filter unit for cleaning purposes or (2) constructed to backwash the filter medium.

SEE OR SEARCH THIS CLASS, SUBCLASS:
433 for a bypass around a filter including those whereby a filter is cleaned by prefilt flow.

This subclass is indented under subclass 409. Apparatus in which a fluid is trapped within the filter, which fluid, upon a release of pressure or cessation of normal flow, acts to force itself or a portion of the filtrate through the filter medium or acts to discharge trapped residue.

This subclass is indented under subclass 409. Apparatus having means to pass a fluid, usually a liquid, through the filter medium in a direction reverse to normal filtering flow.

SEE OR SEARCH THIS CLASS, SUBCLASS:
427 for a flow controller for backwash and see the search notes thereunder.
678 793, and 798, for processes of rehabilitating a separation medium by reverse flow.

This subclass is indented under subclass 411. Apparatus having means to cause a backwash liquid, usually filtrate, to traverse the filter medium as a pressure wave, i.e., having pressures varying between two or more peaks, e.g., pistons reciprocating within a cylindrical filter medium or an intermittently actuated pulsator.

SEE OR SEARCH THIS CLASS, SUBCLASS:
349 for a filter having pulsation dampeners or gas trapping means.
356 for a filter constructed to cause flexing of the medium by a fluid.
359 for a filter having mechanical means for flexing the medium.
384 and 388+, for a filter having vibrating means.
748 for processes involving pulsation or oscillation.

This subclass is indented under subclass 407. Apparatus in which the filter medium is stationary and an agitator and mechanical cleaning means moves relative to it.

SEE OR SEARCH THIS CLASS, SUBCLASS:
357 for a filter having interleaved members for cleaning.

SEE OR SEARCH CLASS:
15, Brushing, Scrubbing, and General Cleaning, 246 for cleaning attachments there provided for.

This subclass is indented under subclass 413. Apparatus in which the fixed filter medium is mounted within a closed casing having plural outlets.

SEE OR SEARCH THIS CLASS, SUBCLASS:
397 422+ and 433, for other filter combinations having plural outlets from a closed casing.

This subclass is indented under subclass 413. Apparatus in which the filter medium has a curved surface and in which the cleaning or agitating means moves about a fixed axis and has nontranslatory rotary motion.

With pump, gas pressure, or suction source:
This subclass is indented under subclass 348. Apparatus provided with a pump or other source of vacuum or pressure which is particularly defined as other than a suction of pressure conduit, acting to aid the flow of fluid through the strainer or filter.

SEE OR SEARCH THIS CLASS, SUBCLASS:
167 for structural installations with a closed circulating system.
194 for recirculation which may include a pump.
251 for a filter combined with a mouthpiece.
258 for serially connected units including a pump.
406 for a filter combined with a vacuum source which does not pump the liquid.
412 for a liquid pulsator acting during backwash of blowback.

SEE OR SEARCH CLASS:
92, Expansible Chamber Devices, 78 for the combination of an expansible chamber device and fluid purifying means which enhances the operation of the device; and see (2) Note in subclass 78 of Class 92 for statement of the line.
166, Wells, 105.1 for well pumps having sediment traps or deflectors; and subclasses 105.5+ for well pumps having liquid-gas separator; i.e., gas anchors.
417, Pumps, appropriate subclasses for the combination of a pump and a filter wherein the specific disclosure of the filter is to protect or enhance the operation of the pump.
418, Rotary Expansible Chamber Devices, subclass 47 for the combination or a rotary expansible chamber pump and a filter wherein the filter is specially disclosed as protecting or enhancing the operation of the pump.

For aquarium or swimming pool:
This subclass is indented under subclass 416.1. Apparatus adapted for use in an aquarium or swimming pool.

SEE OR SEARCH THIS CLASS, SUBCLASS:
169 for closed circulating systems involving swimming pools.

For drinking water:
This subclass is indented under subclass 416.1. Apparatus used to produce drinking water.

For fuel system:
This subclass is indented under subclass 416.1. Apparatus used in a fuel system.

For lubricating or oil treating system:
This subclass is indented under subclass 416.1. Apparatus adapted for use in a lubricating or oil treating system.

SEE OR SEARCH THIS CLASS, SUBCLASS:
168 for closed lubricating system structurally installed.

This subclass is indented under subclass 348. Apparatus in which there are liquid distributors embedded in a filter medium, alternate distributors acting respectively as liquid inlet and discharge means.

SEE OR SEARCH THIS CLASS, SUBCLASS:
343 for similar devices in which the filter elements form plural units.

This subclass is indented under subclass 348. Apparatus with a variable flow controller for the material being treated, or a constituent thereof.

SEE OR SEARCH THIS CLASS, SUBCLASS:
97 for flow, fluid pressure or material level responsive means.
138 for a separator with time control means.
141 for a separator with a program actuator.
143 for automatic control of a separator.
302 for a filter and a constituent trap with a flow line valve.
313 for a filter, a constituent trap and valve controlled sediment discharge means.
340 for parallel similar filters with flow control means.
371 for a variable flow controller for residue in a centrifugal extractor.
390 for a movable medium mounted on a movable valve element.

SEE OR SEARCH CLASS:
137, Fluid Handling, 544 for a flow controller combined with a gas separator.
138, Pipes and Tubular Conduits, subclass 41 for a restrictor and a screen.
166, Wells, subclass 205 for a well screen with a valve or changeable restrictor.

This subclass is indented under subclass 418. Apparatus in which the flow controller is attached to or within a portable prefilt receiver, e.g., funnel or hand manipulated receptacle.

SEE OR SEARCH THIS CLASS, SUBCLASS:
244 for a portable receptacle with hood or closure.

This subclass is indented under subclass 418. Apparatus in which the controller selects the direction of fluid flow from a given source through or by the filter.

SEE OR SEARCH THIS CLASS, SUBCLASS:
130 for a fluid pressure responsive bypass.
190 and 269+, for valve controlled means for bypassing a water softening apparatus during regeneration thereof.

This subclass is indented under subclass 420. Apparatus in which a deflector is pivoted for limited motion for diverting the prefilt to one or more alternate paths, e.g., dirty rain to a receiver and clean rain water to a filter.

SEE OR SEARCH THIS CLASS, SUBCLASS:
99 for a similar organization having means responsive to prefilt accumulation.

This subclass is indented under subclass 420. Apparatus in which the filter element is within a closed casing, which casing has a residue or prefilt outlet in addition to a prefilt inlet and filtrate outlet.

SEE OR SEARCH THIS CLASS, SUBCLASS:
299 particularly subclasses 312+ for a filter combined with a constituent trapping feature and sediment discharge means.

This subclass is indented under subclass 422. Apparatus having at least one inlet and one outlet in a unitary header.

SEE OR SEARCH THIS CLASS, SUBCLASS:
133 for a fluid pressure responsive bypass in a unitary header.
340 for parallel filters with flow control means.

This subclass is indented under subclass 420. Apparatus
including a multiway valve which may be adjusted to direct flow in different directions.

This subclass is indented under subclass 424. Apparatus to control backwash.

SEE OR SEARCH THIS CLASS, SUBCLASS:
278 for a multiway valve unit controlling backwash in a particulate material type separator.

This subclass is indented under subclass 425. Apparatus wherein the valve is within the same housing as the filter.

This subclass is indented under subclass 420. Apparatus to control backwash.

SEE OR SEARCH THIS CLASS, SUBCLASS:
108 for flow, fluid pressure or material level control of backwash.
190 for external regenerating medium supply combinations.
425 for control of backwash by a selective directive multiway valve controller.

This subclass is indented under subclass 418. Apparatus in which there are at least two inflow passages and one outflow passage with the filter in the outflow or (2) at least two outflow passages and one inflow passage with the filter in the inflow; and with a flow controller for any one or more of said passages.

SEE OR SEARCH THIS CLASS, SUBCLASS:
378 for a centrifugal extractor having plural filtrate outlets.

This subclass is indented under subclass 418. Apparatus in which the seat or the stem of the flow controller is coaxial with the filter.

This subclass is indented under subclass 429. Appartus in which the filter surrounds the controller seat or head.

SEE OR SEARCH THIS CLASS, SUBCLASS:
371 for a centrifugal basket having valve means coacting with the bottom of the basket.
426 for a multiway valve unit encased in a filter housing for controlling cleaning by a backwash fluid.

This subclass is indented under subclass 429. Apparatus in which the filter is fixed to the controller seat opposite the controller head.

This subclass is indented under subclass 418. Apparatus in which the filter is in a chamber or recess in the controller body.

SEE OR SEARCH THIS CLASS, SUBCLASS:
426 for an encased multiway valve unit to control fluid cleaning of a filter by backwashing.

Divided filtered, and unfiltered liquid outlet passages:
This subclass is indented under subclass 348. Apparatus comprising two outlet passages for liquid under treatment, one for untreated liquid and one for filtrate.

SEE OR SEARCH THIS CLASS, SUBCLASS:
130 for a pressure-responsive bypass.
254 for serially connected units with a bypass.
321.6 for devices having plural inlets and outlets in which the medium is a dialyzing membrane.
385 for axially reciprocable and rotary filter medium which may act as a bypass.
420 for a variable directive flow controller.
428 for combining and dividing flow passages with a filter in the combined passage.
436 and 472, for a vended filter.

This subclass is indented under subclass 433.1. Apparatus in which the untreated part joins the filtrate.

This subclass is indented under subclass 348. Apparatus wherein the filter medium is totally positioned in a casing which is imperforate except for flow line means for introducing and discharging fluid.

SEE OR SEARCH THIS CLASS, SUBCLASS:
287 for similar structure for a particulate bed.
459 for filters attached to a plate or the end of a pipe.
473 for filter and receptacle combinations in which part of
the receptacle may resemble a pipe, e.g., funnel neck.

SEE OR SEARCH CLASS:
68, Textiles: Fluid Treating Apparatus, subclass 208 for fluid textile treating apparatus having a drain and strainer means associated therewith.

This subclass is indented under subclass 435. Apparatus wherein means for venting the casing is provided.

This subclass is indented under subclass 435. Apparatus in which a liquid receiving means such as a tube or equivalent means forming a flow passage is located centrally of a filter medium or element.

This subclass is indented under subclass 437. Apparatus in which the tube is imperforate at least along a substantial length thereof directing fluid axially of the filter element.

This subclass is indented under subclass 438. Apparatus in which the liquid to be treated flows through the imperforate tube in one direction and through the filter medium, for treating purposes, in a direction opposite to the first mentioned direction of flow.

SEE OR SEARCH THIS CLASS, SUBCLASS:
288 for a particulate material type separator having similar structure.

This subclass is indented under subclass 437. Apparatus in which the prefilt inlet and the filtrate outlet are in the same end of a closed casing.

This subclass is indented under subclass 437. Apparatus in which the central liquid receiving means is directly attached to a part of the casing.

This subclass is indented under subclass 441. Apparatus in which the central liquid receiving means is attached, at each of its ends, to opposed parts of the casing.

This subclass is indented under subclass 435. Apparatus in which the prefilt inlet and the filtrate outlet are in the same end of a closed casing.

SEE OR SEARCH THIS CLASS, SUBCLASS:
133 for fluid pressure responsive bypass in an inlet and outlet closure header.
420 particularly subclass 423 for flow controller combinations with a prefilt inlet and outlet at the same end of the casing.
440 for similar structure with a central liquid receiver.

This subclass is indented under subclass 443. Apparatus in
which the filter element is attached to and extrudes downwardly from an upper part of the casing, usually a removable head.

This subclass is indented under subclass 435. Apparatus in which the filter medium is clamped in a joint of the casing.

SEE OR SEARCH THIS CLASS, SUBCLASS:
227 for sectional pressure type filters in which the medium is clamped in a casing joint.

This subclass is indented under subclass 435. Apparatus in which the prefilt inlet and the filtrate outlet are in substantial axial alignment.

This subclass is indented under subclass 446. Apparatus in which the strainer or filter element is insertable in and removable from the casing by movement generally lateral to the direction of flow of the liquid to be treated, e.g., the axis of the casing or pipe.

SEE OR SEARCH THIS CLASS, SUBCLASS:
310 for a filter and a constituent trap in which the trap is lateral of a flow line.
454 for a filter element attached to a closure.

This subclass is indented under subclass 446. Apparatus in which the filter element is a hollow filter element having one end open.

SEE OR SEARCH THIS CLASS, SUBCLASS:
452 for a single open end type filter supported on an internal fixed shoulder.

This subclass is indented under subclass 446. Apparatus in which the closed casing is attached to and extends beyond the end of a pipe.

SEE OR SEARCH THIS CLASS, SUBCLASS:
459 for a similar filter not enclosed in a casing.

SEE OR SEARCH CLASS:
137, Fluid Handling, 549 for a flow controller combined with gas separating means.

This subclass is indented under subclass 435. Apparatus having (1) opposed members at each end of the element which are separable from the casing with the filter element supported between them, or (2) a gasket between the element and the walls of the casing.

SEE OR SEARCH THIS CLASS, SUBCLASS:
445 for a filter element clamped in a casing joint which may include a gasket.

This subclass is indented under subclass 435. Apparatus in which the casing is provided with an internal shoulder from which the filter element is supported.

SEE OR SEARCH THIS CLASS, SUBCLASS:
477 for a filter resting on an internal stop or surface of a receiver of more general construction.

This subclass is indented under subclass 451. Apparatus in which the filter element is a hollow filter element having a single open end.

SEE OR SEARCH THIS CLASS, SUBCLASS:
448 for an axially aligned inlet and outlet to a casing enclosing a single open end filter element.

This subclass is indented under subclass 435. Apparatus wherein the strainer or filter element is clamped between a removable cover and an opposed wall of the casing.

This subclass is indented under subclass 435. Apparatus in which the filter element is fixed to a removable closure.

SEE OR SEARCH THIS CLASS, SUBCLASS:
244 for a portable receptacle type filter with a closure.
309 for a filter element attached to a sediment trap.
447 for a filter element laterally removable from a flow line even though attached to a closure.

This subclass is indented under subclass 348. Apparatus comprising (1) a supporting receptacle for a filter medium an inner surface of which is modified as by grooves or ribs, or (2) a separate spacing member engaging the inner surface of the receptacle.

SEE OR SEARCH THIS CLASS, SUBCLASS:
224 particularly subclass 231 for a sectional chamber press
filter.
283 for a pervious divider in a particulate bed separator.

This subclass is indented under subclass 348. Apparatus in which the prefilt passes into contact with an imperforate member which serves as a flow restrictor, diverter or distributor for the prefilt, usually to absorb the force of the incoming prefilt or prevent swirling.

SEE OR SEARCH THIS CLASS, SUBCLASS:
247 for a filtrate splash plate or deflector.
279 and 291+, for particular liquid receiving means for a particulate bed type separator.
305 for distinct separators having baffle means cooperating with a sediment trap.
377 for a work distributor in a centrifugal extractor.
405 for a movable prefilt distributor.
421 for a filter with variable flow control means and a pivoted prefilt deflector.

This subclass is indented under subclass 348. Apparatus in which there is a pervious member centrally located within a filter medium.

SEE OR SEARCH THIS CLASS, SUBCLASS:
437 for a filter with a central liquid receiver, which filter is within a flow line or closed casing.
459 for a filter attached to and extending beyond the end of a fluid conducting tube.

This subclass is indented under subclass 457. Apparatus in which there are two or more liquid receivers having a common axis.

SEE OR SEARCH THIS CLASS, SUBCLASS:
315 for one diverse filter spaced within another.
338 for nested concentric filters.
342 for one filter with another.
489 for superimposed filter mediums arranged for series flow.

This subclass is indented under subclass 348. Apparatus in which the filter element is mounted on a pipe, plate or wall.

SEE OR SEARCH THIS CLASS, SUBCLASS:
103 for grated inlet surface drains.
172 for a separator ancillary to a tank for storage of fluid for use other than that of this class (210).
457 for a filter element having a central pervious liquid receiving tube.
473 for a filter attached to a portable receiver, as a funnel.

SEE OR SEARCH CLASS:
166, Wells, 227 for well screens and see the Notes thereto.

This subclass is indented under subclass 459. Apparatus in which the filter element or its supporting structure is mounted on the open end of the pipe and extends beyond the open end.

SEE OR SEARCH THIS CLASS, SUBCLASS:
449 for a filter element totally enclosed in a flow confining casing attached to a pipe.
482 for a filter secured to the lower end of a prefilt receiver, said lower end being similar in structure to a pipe.

This subclass is indented under subclass 460. Apparatus in which the filter element encloses a space except for a single inlet or outlet, other than those in the filter medium, the filtering medium having walls which are spaced from each other.

SEE OR SEARCH THIS CLASS, SUBCLASS:
224 particularly subclass 231 for a sectional chamber press type filter.
346 for plural units of the spaced wall type.
486 for spaced wall type elements.

This subclass is indented under subclass 460. Apparatus in which the pipe or tube is in turn connected to a plate or wall.

This subclass is indented under subclass 460. Apparatus comprising means forming a part of or attached to a filter element, which means is inserted into the open end of a pipe.

SEE OR SEARCH CLASS:
52, Static Structures (e.g., Buildings), subclass 12 for a cover with an eave or valley gutter and a separator.
222, Dispensing, 189.06 for dispensers having a filter.

This subclass is indented under subclass 348. Apparatus mounted at the top of or on the spout of a portable receptacle functioning when the receptacle is tipped.

SEE OR SEARCH THIS CLASS, SUBCLASS:
473 for a filter mounted at the inlet to a receptacle.

This subclass is indented under subclass 464. Apparatus comprising a handle on the receptacle and on the filter positioned for cooperation with each other.

SEE OR SEARCH THIS CLASS, SUBCLASS:
470 for a filter with a handle and see the Notes thereto.

This subclass is indented under subclass 464. Apparatus in which the filter is mounted on or adjacent the receptacle spout.

SEE OR SEARCH THIS CLASS, SUBCLASS:
316 for spaced filters, one adjacent an inlet or outlet conduit.
460 for a filter attached to an open end of a pipe.

This subclass is indented under subclass 466. Apparatus in which the filter is within the receptacle so as to block flow of solids to the spout inlet.

This subclass is indented under subclass 466. Apparatus in which the filter is mounted at the discharge end of the spout spaced from such end.

SEE OR SEARCH THIS CLASS, SUBCLASS:
248 for a device having drip catching features or means.

This subclass is indented under subclass 464. Apparatus in which the filter is mounted on or adjacent the upper edge of the receptacle.

SEE OR SEARCH THIS CLASS, SUBCLASS:
245 for a similar device including a valve or flow restrictor.
474 for a similar device mounted on a filtrate receiver.
479 for a filter mounted on the upper edge of a filtrate receiver.

This subclass is indented under subclass 348. Apparatus provided with handle means.

SEE OR SEARCH THIS CLASS, SUBCLASS:
237 for repair and disassembly means having a handle.
244 for a portable receptacle with a hood or closure which may include a handle.
465 for a handled portable receptacle and handled drainer.

SEE OR SEARCH CLASS:
209, Classifying, Separating, and Assorting Solids, 417 for a sifter provided with manual manipulating means.
222, Dispensing, subclass 465.1 for a dispensing container having a handle.

This subclass is indented under subclass 470. Apparatus comprising a ring member fixedly attached to the filter.

SEE OR SEARCH THIS CLASS, SUBCLASS:
495 for a ring and screen type filter element.

This subclass is indented under subclass 348. Apparatus, including means to vent the filter or filtrate receiver.

SEE OR SEARCH THIS CLASS, SUBCLASS:
120 for flow, fluid pressure or material level responsive vent control.
180 for vapor or gas removal in a treatment device with heating means.
436 for a vented filter within a flow line.

This subclass is indented under subclass 348. Apparatus, including structure to support the filter on or readily attach the filter to a liquid receiver or container.

SEE OR SEARCH THIS CLASS, SUBCLASS:
419 for a portable prefilt receiver with a flow controller.
451 for a filter in a flow line or closed casing supported on an internal shoulder.
464 for a portable receptacle draining type filter.

This subclass is indented under subclass 473. Apparatus supported at the upper edge of the receiver.

SEE OR SEARCH THIS CLASS, SUBCLASS:
471 for a device having a ring and handle which may rest on the upper edge of receptacle.

This subclass is indented under subclass 474. Apparatus in which the filter is offset from the center of a cover of the filtrate receiver.

This subclass is indented under subclass 474. Apparatus in which two or more liquid receivers are telescoped within each other.

SEE OR SEARCH THIS CLASS, SUBCLASS:
445 for a filter element clamped between means providing a joint in a pipe or casing.
446 for a filter medium attached to a telescopic pipe section.

This subclass is indented under subclass 473. Apparatus in which the filter medium or its support rests on an internal stop or surface of the receptacle wall.

SEE OR SEARCH THIS CLASS, SUBCLASS:
455 for a filter on a modified spacing surface of a casing.

SEE OR SEARCH CLASS:
99, Foods and Beverages: Apparatus, 279 for beverage infusors including more than a filter medium or such medium and a supporting receptacle.
222, Dispensing, 189.06 for dispensers having a filter.

This subclass is indented under subclass 477. Apparatus in which a radially expansible retainer, such as a resilient ring or downwardly projecting spring arms, and the filter form an integral unit.
(1) Note. The term "integral unit" means a filter medium and a retainer so connected that the unit cannot be disassembled without destroying the unit or can be disassembled only be removing mechanical connectors, such as a bolt or rivet.

SEE OR SEARCH THIS CLASS, SUBCLASS:
463 for a filter element which may be expandable in a pipe.

This subclass is indented under subclass 477. Apparatus in which there is a member within the prefilt receiver usually a ring or cylinder, which clamps or retains the filter medium and/or its supporting structure against the inner wall of the prefilt receiver or against the stop member.

This subclass is indented under subclass 479. Apparatus in which the retainer is expandable and has means for contracting the retainer to effect release of the filter medium.

SEE OR SEARCH THIS CLASS, SUBCLASS:
238 for a filter element and a handle for removing the element from a casing.

This subclass is indented under subclass 477. Apparatus extending longitudinally of the prefilt receiver, e.g., reflux type coffee makers or funnels having means extending into the funnel neck to hold the filter unit in place.

SEE OR SEARCH CLASS:
99, Foods and Beverages: Apparatus, subclass 292 for pressure-vacuum or reflux type beverage infusors having more than filter and its support.

This subclass is indented under subclass 473. Apparatus attached or supported at the lower end of a prefilt receiver.

SEE OR SEARCH THIS CLASS, SUBCLASS:
449 for a filter medium within a closed casing attached to a pipe end.
459 for a filter element attached to a fixed pipe or plate.

This subclass is indented under subclass 348. Apparatus comprising: (1) a filter medium and supporting means therefore, (2) a filter medium having a defined significant gross structure or shape, or (3) super-imposed or abutted members forming a single filter element.

SEE OR SEARCH THIS CLASS, SUBCLASS:
500 for filter material, per se.

SEE OR SEARCH CLASS:
209, Classifying, Separating, and Assorting Solids, 363, especially subclasses 409+, for filter elements for separating solids.
413, Sheet Metal Container Making, 1 for sheet-metal ware making processes which may include processes of making filter elements.

This subclass is indented under subclass 483. Apparatus in
which the filtering medium is retained within a foraminous supporting container or sheath, e.g., removable cartridges.

SEE OR SEARCH THIS CLASS, SUBCLASS:
317 for similar structures with plural spaced filters.

This subclass is indented under subclass 483. Apparatus comprising supporting structure outside of the filter medium formed of spaced bars supporting a nonplanar filter medium.

SEE OR SEARCH THIS CLASS, SUBCLASS:
455 for similar structure in which the supporting structure spaces the filter medium from a receptacle wall.
497 for a cylindrical filter having external reinforcing means.

This subclass is indented under subclass 483. Apparatus in which the medium comprises spaced walls.

SEE OR SEARCH THIS CLASS, SUBCLASS:
461 for similar structure attached to the open end of a pipe.

This subclass is indented under subclass 486. Apparatus comprising (1) concentric walls, (2) spirally arranged, or (3) pleated.

This subclass is indented under subclass 483. Apparatus comprising separable members which abut on their surfaces of
greatest dimension or which are aranged in superposed relation.

This subclass is indented under subclass 488. Apparatus so arranged that the liquid passes through them in succession.

SEE OR SEARCH THIS CLASS, SUBCLASS:
335 for plural distinct filters arranged for series flow.

SEE OR SEARCH CLASS:
55, Gas Separation, subclass 482, 485, and 486+ for layered or serially arranged gas filters.

This subclass is indented under subclass 489. Apparatus in which (1) the layers are integrally united as by an adhesive or one material is partially diffused into another, or (2) each layer comprises a coated or impregnated material.

This subclass is indented under subclass 490. Apparatus in which all of the layers are fibrous.

This subclass is indented under subclass 488. Apparatus comprising alternating members dissimilar in shape, size openings within them or similar shaped members arranged in different relative positions.

Pleated:
This subclass is indented under subclass 483. Apparatus in which the filter medium is folded back and forth upon itself.

SEE OR SEARCH CLASS:
55, Gas Separation, 497, 500, and 521 for gas filters of zig-zag form.

Bonded end caps:
This subclass is indented under subclass 493.1. Apparatus wherein the filter medium is permanently attached to the end caps.

Rectangulary shaped:
This subclass is indented under subclass 493.1. Apparatus in the form of a rectangle.

Spirally formed:
This subclass is indented under subclass 493.1. Apparatus having a helically shaped filter medium.

Filter element:
This subclass is indented under subclass 493.1. Apparatus consisting of a single component of the pleated filter apparatus.

Convolute:
This subclass is indented under subclass 483. Apparatus in which the filter medium is arranged so that it is coiled upon itself and recedes or approaches a center axis.

SEE OR SEARCH THIS CLASS, SUBCLASS:
493.4 and 497.1, for pleated spirally formed and helically wound filters, respectively.

Metal:
This subclass is indented under subclass 494.1. Apparatus made from metal.

With edge spacer:
This subclass is indented under subclass 494.1. Apparatus having means at the edge of the filter medium to space consecutive convolutions.

This subclass is indented under subclass 483. Apparatus in which the supporting means comprises a ring or noncircular frame.

SEE OR SEARCH THIS CLASS, SUBCLASS:
471 for a filter having a handled ring frame.
485 for a filter enclosed in a cage support.

This subclass is indented under subclass 483. Apparatus in which the medium is composed of particles or fibers bound together into a single integral unit, by fusing, an adhesive or the intertwining of fibers.

Cylindrical, conical, or trough shaped:
This subclass is indented under subclass 483. Apparatus in which the filter medium is shaped to form a cylinder, cone, or open trough.

SEE OR SEARCH THIS CLASS, SUBCLASS:
380.1 for a centrifuge basket.
433.1 for a through flow tubular type filter.

SEE OR SEARCH CLASS:
55, Gas Separation, subclass 498, 500, and 521 for gas filters of cylindrical or conical form.

This subclass is indented under subclass 497.01. Apparatus which comprises a filter formed from indefinite length material coiled in such a manner as to generate convolutions about an axis with each convolution displaced along said axis from the previous convolutions.

SEE OR SEARCH THIS CLASS, SUBCLASS:
494.1 for convolute wound filters.

Filter blank:
This subclass is indented under subclass 497.01. Apparatus in an unassembled form capable of being formed in a cylindrical, conical, or trough shape.

Conical:
This subclass is indented under subclass 497.01. Apparatus in the form of a cone.

This subclass is indented under subclass 483. Apparatus comprising a perforated plate or a plate having grooves in its surface to form liquid flow passages.

SEE OR SEARCH CLASS:
209, Classifying, Separating, and Assorting Solids, 397 for perforated sheet sifter elements.

This subclass is indented under subclass 483. Apparatus, comprising meshed fabric.

SEE OR SEARCH CLASS:
139, Textiles: Weaving, 383 for fabrics having no particular shape or specific structure peculiar to filtering.
166, Wells, 277 for well screens, particularly subclass 230 for woven mesh well screens, and subclass 234 for well screens comprising spaced strips or bars.
209, Classifying, Separating, and Assorting Solids, 392 for sifter elements there provided for.
245, Wire Fabrics and Structure, appropriate subclasses, for such structure of general utility.

Material:
This subclass is indented under subclass 348. Compositions comprising materials to be used in filter apparatus.
(1) Note. Materials consisting of fibers (e.g., paper) comprising a homogeneous mass of fibers, with or without binders or randomly dispersed fillers made by a Class 162 method are in Class 162 even though defined as a filter material. Such material having additional features peculiar to filtration are in Class 210, subclasses, 500.1+ e.g., perforations, fibers on a perforated backing, strata of fibers of different kinds, etc.
(2) Note. A patent for stock material which may have filtering properties but in which there is no claimed internal or external structure particularly adapting the material for use as a filter will be placed in the appropriate stock material class. See, especially, Class 428, Stock Material or Miscellaneous Articles, and the search
notes thereunder.
(3) Note. A composition claimed or disclosed solely as a sorbent or claimed as a filter aid and disclosed to aid filtering solely as a sorbent is classifiable in Class 502. A composition claimed as filtering material i.e., by presenting apertures or interstices of a size functioning to retain solid matter by a screening or sieving action with or without a sorbing action is classifiable in Class 210, subclasses 500.1+. Class 210, subclass 500.1 filter material is superior to Class 502. A copy of a patent properly classified in 210, subclasses 500.1+ will be crossed to Class 502 only on the basis of a novel sorbent material.

SEE OR SEARCH THIS CLASS, SUBCLASS:
483 for supported, shaped, or superimposed filter mediums.

SEE OR SEARCH CLASS:
106, Compositions: Coating or Plastic, appropriate subclasses for plastic compositions in general, and see (2) Note of that class definition.
139, Textiles: Weaving, 383 for fabrics having no particular shape or specific structure peculiar to filtering.
162, Paper Making and Fiber Liberation, (see (1) Note).
204, Chemistry: Electrical and Wave Energy, 295 for diaphragms or membranes to be used in electrolytic apparatus.
252, Compositions, 175 for water softening or purifying compositions; subclasses 182.11+ for filter materials which exert a chemical action.
428, Stock Material or Miscellaneous Articles, 304.4 for a product of composite form in which one component is either porous or cellular and subclasses 357+ for a mass or layer of structurally defined or coated elements (e.g., fibers, filaments, particles).
429, Chemistry: Electrical Current Producing Apparatus, Product and Process, 129 and 247+ for separators (diaphram) specialized for that class.
442, Fabric (Woven, Knitted, or Nonwoven Textile or Cloth, etc.), 409 for an autogenously bonded nonwoven fabric.
502, Catalyst, Solid Sorbent, or Support Therefor: Product or Process of Making, for a composition comprising a catalyst or sorbent, per se.

Semipermeable membrane:
This subclass is indented under subclass 500.1. Subject matter directed to semipermeable membrane specified primarily in terms of the nature of the composition or compositions of which it is made.
(1) Note. See "membrane" and the reference therein to "semipermeable membrane" in the Glossary of the main class definition of this class.
(2) Note. For a membrane having structure (said structure may, for example, be described in terms of, being semipermeable or selective or permselective, defining pore dimension or shape, flux or permeation rate, retention characteristics, porosity, overall membrane shape (e.g., tube or hollow fiber), pore configuration (for example, symmetric (e.g., isotropic or unskinned) or asymmetric (e.g., anisotropic or skinned), bubble point, birefringence, etc.), which is disclosed to be solely or primarily useful in a Class 210, Liquid Purification or Separation process (e.g., dialysis, reverse osmosis, ultrafiltration, hyperfiltration, microfiltration) classification in Class 210 is proper. For a membrane which is a stock material disclosed to be of more general utility (e.g. not primarily useful for such a Class 210 process) and for which no such structure is claimed, classification in the appropriate stock material class is proper. A membrane of only nominally recited structure, i.e., simply characterized as a membrane or film without any other significant structure such as that referred to above, of a specific chemical composition, is properly classifiable in the appropriate chemical composition class. Class 210 is superior to Class 96. Consequently, membranes claimed for use in Class 96, Gas Separation: Apparatus (including membranes for removal of a gas from a liquid) and claimed for use in Class 210, Liquid Purification or Separation apparatus (or membranes for "fluid" separation) are classified in Class 210 as originals and cross-referenced to Class 96. For membranes or diaphragms useful for: (a) processes of electrical, radiant, wave energy or magnetic separation or purification of liquids (including more than the mere application of a magnetic field to liquid to separate magnetic particles therefrom) classification in Class 204 is proper; (b) processes of use as a battery separator, classification in Class 429 is proper: however, in regard to membranes useful in processes of both Classes 210 and 204 and/or 429, Class 210 subclasses 500.1+ has superiority over both Classes 204 and 429, based upon 210 subclasses 500.1+ occurring first in the Patent Office classes of the Manual of Classification.

SEE OR SEARCH THIS CLASS, SUBCLASS:
321.6 for membrane containing apparatus and see the search notes thereunder.

Isotropically pored:
This subclass is indented under subclass 500.21. Subject matter comprising a membrane structure, defining two major surfaces, and which includes pores which extend between the major surfaces, the pores having a substantially uniform cross section throughout.

Hollow fiber or cylinder:
This subclass is indented under subclass 500.21. Subject matter in the shape of either an annulus or of a cylindrical hollow structure which is relatively elongated compared with its diameter.
(1) Note. Such a structure maybe described as, e.g., a tube, a capillary, or a hollow fiber.

Antithrombogenic coating on membrane:
This subclass is indented under subclass 500.21. Subject matter wherein the membrane comprises a surface coating of a material specialized to prevent the formation of blood clots.

Metal containing:
This subclass is indented under subclass 500.21. Subject matter wherein the membrane comprises a metal present ineither elemental form or in a compound of that metal.

Glass:
This subclass is indented under subclass 500.21. Subject matter wherein the membrane comprises a glass.
(1) Note. Glasses are inorganic compositions which solidify from the molten state without crystallizing, to have that
molecular disorder characteristic of the glassy state, which have no definite melting point, are incapable in the solid state of permanent deformation, which fracture when subjected to deformation tension and include as components at least one "glass former" material.
(2) Note. Typical glass formers are, e.g., oxides of silicon, beryllium, boron, germanium, phosphorus, vanadium, lead, tin, zinc, zirconium, and titanium, as well as such nonoxide compounds as GeS, metal fluorides, or iodides, and some metallic selenides, tellurides, arsenides, and phosphides. These compositions may also include other oxides devoid of glass forming tendencies, e.g., oxides of alkali metals, alkaline earth metals, and magnesium.
(3) Note. Many ceramic compositions contain primarily slag, the byproduct of metal refining and smelting, which are considered to be glasses.
(4) Note. Neither transparency to light nor the absence of color are necessary for a composition to be considered as a glass for the purpose of this subclass.
(5) Note. Water glass, Plexiglas, and isinglass are not considered to be glass for the purpose of classification in this subclass.
(6) Note. Organic, noncrystalline solid materials, such as synthetic resins which may referred to as organicglasses, e.g., Plexiglas, are not considered to be glass for the purpose of classification in this subclass.
(7) Note. The so-callled metallic glasses or glassy metals, which are amorphous solid forms of metals ar not included herein.

Organic:
This subclass is indented under subclass 500.21. Subject matter comprising an organic substance.
(1) Note. Organic is intended to include substances which have a carbon atom bonded to another carbon atom, or to a halogen atom, or to a hydrogen atom, or to a nitrogen atom by a single or a double bond.

Cyclic:
This subclass is indented under subclass 500.27. Subject
matter comprising an organic substance which includes a ring structute, i.e., a series of atoms bonded one to another in such a fashion that the chain closes upon itself.

Cellulosic:
This subclass is indented under subclass 500.28. Subject matter comprising the structure known as cellulose, or derivatives thereof in which the basic cellulose structure remains intact.

Cellulose acetate:
This subclass is indented under subclass 500.29. Subject matter comprising esters of cellulose with acetic acid, i.e., containing at least one -O-C(=O)-CH[subscrpt]3[end subscrpt] group.

Cellulose diacetate:
This subclass is indented under subclass 500.30. Subject matter comprising a cellulose acetate in which the cellulose ester includes two and only two-O-C(=O)-CH[subscrpt]3[end subscrpt] groups.

Cellulose triacetate:
This subclass is indented under subclass 500.30. Subject matter comprising a cellulos acetate in which the cellulose ester includes three -O-C(=O)-CH[subscrpt]3[end subscrpt] groups.

Homocyclic:
This subclass is indented under subclass 500.28. Subject matter comprising at least one ring wherein all the ring atoms are carbon atoms.

Styrene:
This subclass is indented under subclass 500.33. Subject matter comprising a six membered carbon ring having attached thereto a -CH=CH[subscrpt]2[end subscrpt] groups.

Acrylate:
This subclass is indented under subclass 500.27. Subject matter comprising a O-C-C=C group.

Alkene other than vinyl:
This subclass is indented under subclass 500.27. Subject matter comprising an aliphatic unsaturated hydrocarbon containing a nonterminal carbon to carbon double bond.

Amine:
This subclass is indented under subclass 500.27. Subject matter comprising an atom of carbon bonded to an atom of nitrogen, which structures are the equivalent of a structure formed from ammonia (NH[subscrpt]3[end subscrpt]) by replacement of one, two, or three of the hydrogens with carbon atoms.

Amide:
This subclass is indented under subclass 500.37. Subject matter comprising a -C(=O)-NH[subscrpt]2[end subscrpt] group or similar groups derived from acid other than a carboxylic acid by replacing the acidic hydrogen with an NH[subscrpt]2[end subscrpt] Group.
(1) Note. Such materials may be identified as, e.g., Nylon.

Imide:
This subclass is indented under subclass 500.38. Subject matter including the group: R-C-N-C-R.

Carbonate:
This subclass is indented under subclass 500.27. Subject matter comprising a -CO[subscrpt]3[end subscrpt] group.
(1) Note. Such materials may typically be, e.g., polycarbonate resins.

Sulfone:
This subclass is indented under subclass 500.27. Subject matter comprising an R-S-R group.

Vinyl:
This subclass is indented under subclass 500.27. Subject matter comprising a CH[subscrpt]2[end subscrpt]=CH[subscrpt]2[end subscrpt] group.
(1) Note. When polyvinyl synthetic resins are present, various of the hydrogens may be replaced by other atoms.

Acrylonitrile:
This subclass is indented under subclass 500.42. Subject matter comprisiang a CH[subscrpt]2[end subscrpt] = CH-C=N group.
(1) Note. When polyacrylonitrile resins are present, various of the hydrogen atoms may be replaced by other atoms.

This subclass is indented under subclass 500. Compositions including a sterilizing component.

SEE OR SEARCH CLASS:
252, Compositions, 175 for a water softening or purifying or scale inhibiting composition.
424, Drug, Bio-Affecting and Body Treating Compositions, appropriate subclass for a composition which is biocidal to a micro-organism (other than algae), e.g., bacterium, fungus, etc.
504, Plant Protecting and Regulating Composition, 150 for an algicidal composition.

Sorptive component containing:
This subclass is indented under subclass 500. Compositions including a component having the property of removing at least one constituent from a liquid mixture by surface attraction or allowing said constituent to penetrate within the component.

SEE OR SEARCH THIS CLASS, SUBCLASS:
660 especially 679, for processes which use such compositions.

SEE OR SEARCH CLASS:
502, Catalyst, Solid Sorbent, or Support Therefor: Product or Process of Making, for a composition comprising a catalyst or sorbent, per se, and see especially 60 and 400+ for a sorbent.

This subclass is indented under subclass 500. Subject matter comprising (1) granules differing in shape or composition, (2) fibers differing in shape or composition, or (3) combined granules and fibers.
(1) Note. The materials may be laminated, imbedded in each
other or be of one layer having differing sections, e.g., precoated elements.

SEE OR SEARCH THIS CLASS, SUBCLASS:
488 for formed laminated members forming a unitary filter element.
510 for fused or sintered porous material.

SEE OR SEARCH CLASS:
428, Stock Material or miscellaneous Articles, 292.1 for a stock material product in the form of a composite sheet or web embodying a component having structurally defined fibers, subclasses 323+ for such a product embodying a component having structurally defined particles, and subclasses 357+ for a mass or layer of structurally defined or coated element (e.g., fibers, filaments, particles).

This subclass is indented under subclass 503. Compositions having a coating or impregnant, permanently adhered thereto.

SEE OR SEARCH CLASS:
428, Stock Material or Miscellaneous Articles, 323 for stock material product in the form of a composite web or sheet embodying a component having structurally defined fibers or particles, respectively, which product may be coated or impregnated, subclasses 357+ for a mass or layer of structurally defined or coated elements (e.g., fibers filaments or particles, etc.), which may be coated or impregnated in addition to the defined structure.
442, Fabric (Woven, Knitted, or Nonwoven Textile or Cloth, etc.), 59 for a coated or impregnated fabric.

This subclass is indented under subclass 503. Compositions in which at least one component is fibrous.

SEE OR SEARCH CLASS:
428, Stock Material or Miscellaneous Articles, 292.1 for a fiber-containing web or sheet subclasses 375+ for a mass or layer of structurally defined or coated fibers or filaments.

This subclass is indented under subclass 500. Compositions in which the material is coated or impregnated or held together by a binder.

SEE OR SEARCH THIS CLASS, SUBCLASS:
504 for coated or impregnated diverse granules or fibrous materials.

SEE OR SEARCH CLASS:
428, Stock Material or Miscellaneous Articles, appropriate subclasses, especially 175, 190, 193, and 196+ for fabrics or textiles in general, which may be coated or impregnated.
442, Fabric (Woven, Knitted, or Nonwoven Textile or Cloth, etc.), 59 for a coated or impregnated fabric.

This subclass is indented under subclass 506. Compositions comprising a woven or knitted fabric.

SEE OR SEARCH CLASS:
442, Fabric (Woven, Knitted, or Nonwoven Textile or Cloth, etc.), 59 for a coated or impregnated woven or knitted fabric.

This subclass is indented under subclass 506. Compositions which include fibers.

SEE OR SEARCH THIS CLASS, SUBCLASS:
489 for abutted fibrous members.
496 for bound, fused or matted fibrous structures.

SEE OR SEARCH CLASS:
106, Compositions: Coating or Plastic, subclass 242, 282, 699+, and 711 for coating or plastic compositions containing fibers.
428, Stock Material or Miscellaneous Articles, 105 and 114 for a stock mate rial product in the form of a composite web or sheet in which filamentary or fibrous elements in respective layers or components are in angular or parallel relationship, respectively; subclasses 357+ for a layer or mass of structurally defined or coated fibers or filaments.
442, Fabric (Woven, Knitted, or Nonwoven Textile or Cloth, etc.), 59 for a coated or impregnated fabric.
501, Compositions: Ceramic, 35 for glass compositions containing fibers; and subclass 95 for refractory composition containing fibers.

This subclass is indented under subclass 508. Compositions in which the fibers are inorganic, e.g., asbestos or glass wool.

SEE OR SEARCH CLASS:
428, Stock Material or Miscellaneous Articles, subclass 210, 317.9, 325, 426+, and 443+ for a stock material form of a single or plural layer web or sheet which may include glass or asbestos fibers or filaments.
442, Fabric (Woven, Knitted, or Nonwoven Textile or Cloth, etc.), 20, 54+, 172+, 266, 331, 348, and 367 for a fabric which may include glass or inorganic fibers or filaments.

Porous unitary mass:
This subclass is indented under subclass 500. Compositions in which the material is held together by fusing or sintering.

SEE OR SEARCH CLASS:
75, Specialized Metallurgical Processes, Compositions for Use Therein, Consolidated Metal Powder Compositions, and Loose Metal Particulate Mixtures, subclass .5 for metal powders.
106, Compositions: Coating or Plastic, subclass 122, 601+ and 672+ for coating or plastic pore forming compositions.
166, Wells, subclass 228 for porous material well screens.
419, Powder Metallurgy Processes, subclass 2 for processes of making sintered porous articles from metal.
428, Stock Material or Miscellaneous Articles, subclass 566 for metal particle-containing stock material distinguished by an interconnected void structure.
521, Synthetic Resins or Natural Rubbers, 50 for pore forming, per se in a synthetic resin or natural rubber composition.

This subclass is indented under the class definition. Apparatus in which a separating medium comprises a liquid.

SEE OR SEARCH THIS CLASS, SUBCLASS:
634 for processes of solvent extraction.

SEE OR SEARCH CLASS:
196, Mineral Oils: Apparatus, subclass 14.52 for apparatus for separating mineral oil by solvents.
422, Chemical Apparatus and Process Disinfecting, Deodorizing, Preserving, or Sterilizing, 256 for apparatus for extracting a liquid with a liquid.

TANGENTIAL FLOW OR CENTRIFUGAL FLUID ACTION:
This subclass is indented under the class definition. Apparatus wherein fluid flows tangentially of a container in a manner to produce a whirling motion or there is driven means to rotate the fluid.

SEE OR SEARCH THIS CLASS, SUBCLASS:
304 for a tangential inlet, or spiral or convolute baffle in combination with a filter.

SEE OR SEARCH CLASS:
55, Gas Separation, 400 and 447+ for similar type gas separators.
209, Classifying, Separating, and Assorting Solids, 725 for methods and apparatus for removing plural grades or classes of solids from a liquid suspension and subclasses 710+ for analogous treatment of a gaseous suspension.

Multiple cyclone:
This subclass is indented under subclass 512.1. Apparatus in the form of plural cyclone separators.

With movable means affecting flow:
This subclass is indented under subclass 512.1. Apparatus having means which is movable, e.g., rotatable, etc., by either an external source or a fluid within the apparatus. The means functions to impart a whirling or rotary motion to the fluid.

This subclass is indented under the class definition. Apparatus comprising a container or tank in which a mixture of liquids or liquids and solids are separated from one another by forming constituent layers in accordance with their respective sepcific gravities.

SEE OR SEARCH THIS CLASS, SUBCLASS:
187 for a heat exchanger within a gravitational separator.
207 for a distinct reactor tank within a gravitational separator.
265 for a particulate material separator with a gravitational separator.
299 for a filter and a constituent trap.
800 for a process of gravitational separation.

SEE OR SEARCH CLASS:
55, Gas Separation, 434 for gas separators in which the gas current is deflected to effect separation.
99, Foods and Beverages: Apparatus, subclass 456 for separation of a dairy food one of which is a liquid.
127, Sugar, Starch, and Carbohydrates, subclass 13 and 27 for sugar or amylaceous material separating and purifying settling tanks.
137, Fluid Handling, subclass 172 for fluid handling apparatus including means to separate two liquids from each other.
141, Fluent Material Handling, With Receiver or Receiver Coacting Means, subclass 110 for ladles usable with gravitational separators.
166, Wells, 105.1 for well pumps having sediment traps or deflectors and subclasses 105.5+ for liquid-gas separators; i.e., gas anchors.
209, Classifying, Separating, and Assorting Solids, 155 for separating solids by suspending them in a liquid.

This subclass is indented under subclass 513. Apparatus comprising means which cooperates with an invertible, portable container to isolate one constituent after inversion of the container; or after isolation with a single opening of the container extending upwardly, one constituent is withdrawn by inversion of the container.

This subclass is indented under subclass 514. Apparatus in which an isolating means and an inverting position of the container determines which constituent will be withdrawn.

This subclass is indented under subclass 514. Apparatus in which the isolating means is resilient and deformable to permit insertion into the container.

This subclass is indented under subclass 516. Apparatus in which the isolator is hinged to a handle.

This subclass is indented under subclass 514. Apparatus in which the isolator is formed of parts to permit angular rearrangement for insertion in the container.

This subclass is indented under subclass 513. Apparatus having a distributor at an inlet for supplying the material to the container.

SEE OR SEARCH THIS CLASS, SUBCLASS:
273 for a moving distributor to a particulate material separator.
343 and 417, for alternately opening distributors.
377 for a centrifugal extractor having a prefilt distributor.

This subclass is indented under subclass 519. Apparatus which is rotatable.

This subclass is indented under subclass 513. Apparatus having baffle or partition means arranged above the bottom and laterally of the side of the container forming compartments and heavier constituent receiving surfaces.

This subclass is indented under subclass 521. Apparatus with means to withdraw the lighter constituent from at least two compartments.

This subclass is indented under subclass 513. Apparatus including mechanical means for moving a constituent.

SEE OR SEARCH THIS CLASS, SUBCLASS:
221 for froth flotation with a scum remover.
298 for a sediment mover in a diverse operation separator.
407 for residue removing means for a filter.

SEE OR SEARCH CLASS:
30, Cutlery, 324 for spoons.
141, Fluent Material Handling, With Receiver or Receiver Coacting Means, 110 for ladles.

This subclass is indented under subclass 523. Apparatus comprising different serially associated movers.

This subclass is indented under subclass 523. Apparatus which removes sediment from the tank bottom and scum at the surface.

This subclass is indented under subclass 523. Apparatus comprising an endless belt or chain.

This subclass is indented under subclass 523. Apparatus comprising a carriage which moves rectilinearly.

This subclass is indented under subclass 523. Apparatus comprising a scraper which rotates horizontally.

This subclass is indented under subclass 528. Apparatus wherein the scraper is so constructed that in its movement it conforms with the outline of a polygonal tank.

This subclass is indented under subclass 528. Apparatus wherein the scraper is supported by a carriage moving on the rim of the tank.

This subclass is indented under subclass 528. Apparatus in which the scraper is elevatable.

Heavier constituent trap, chamber, or recess:
This subclass is indented under subclass 513. Apparatus providing a trap, chamber, or recess for receiving the heavier constituent.

SEE OR SEARCH CLASS:
166, Wells, 105.1 for well pumps having sediment traps or deflectors; and subclasses 105.5+ for liquid-gas separators; i.e., gas anchors.

Septic tank:
This subclass is indented under subclass 532.1. Apparatus in the form of a septic tank.

SEE OR SEARCH THIS CLASS, SUBCLASS:
170 for a septic tank installed in a geos:graphicial feature.

This subclass is indented under subclass 532. Apparatus wherein the heavier constituent is discharged through a closure or valve controlled port.

SEE OR SEARCH THIS CLASS, SUBCLASS:
112 for control by flow material level or fluid pressure responsive means.
312 for similar structure in diverse separators.

SEE OR SEARCH CLASS:
251, Valves and Valve Actuation, subclass 144 for a valve mounted on a tank of general utility.

This subclass is indented under subclass 533. Apparatus in which the bottom wall of the separator has a portion with at least one sloping wall into which the heavier constituent drains.

This subclass is indented under subclass 534. Apparatus in which the valve is spaced in a flow line for the heavier constituent and is downstream from the separator.

This subclass is indented under subclass 533. Apparatus in which the closure or valve is in the side wall of the separator.

This subclass is indented under subclass 533. Apparatus wherein the container has discharge means for two or more lighter constituents.

This subclass is indented under subclass 513. Apparatus in which a lighter constituent is prevented from escaping from an outlet for a heavier constituent.

This subclass is indented under subclass 538. Apparatus having a gas vent or bypass from the separating compartment of the tank.

SEE OR SEARCH CLASS:
137, Fluid Handling, 587 for a tank with a gas vent and inlet and outlet.