CPC Definition - Subclass F04B
This place covers:
Pumps or compressors which cause a fluid to move by trapping a fixed amount of said fluid, and then forcing or displacing the trapped fluid into discharge means.
Reciprocating pumps or compressors causing the fluid to move using one or more oscillating pistons, plungers or flexible working members, i.e. membranes, diaphragms or tubes.
Related subclasses F02M, F02B and F03C partly cover the same type of structural apparatus using reciprocating or oscillating pistons or flexible working members for positive displacement.
The characteristic used for distinguishing the types of machines is the working fluid used, i.e. a liquid for a pump and an elastic fluid for a compressor.
If the machine may be operated with a liquid as a working fluid both as a hydraulic engine and/or as a pump, then the document is classified in F03C and in F04B. However, if the machine may be operated only as a hydraulic motor, then the document is classified in F03C, and if the machine may be operated only as a pump, then the document is classified in F04B.
Hydraulic motors with reciprocating or rotary pistons for liquid working fluids are classified in F03C. Machines with reciprocating or rotary pistons for working fluids containing elastic fluids, e.g. a combination of liquids and elastic fluids are classified in F01C. Internal combustion piston engines or combustion engines in general, where the driving forces are generated by expansion of gases due to combustion are classified in F02B.
Subject matter like cyclically operating valves, lubricating or cooling are classified in subclasses F01L, F01M, F01P irrespective of their stated application, unless their novel and non-obvious features are peculiar to their application, in which case they are classified only in the relevant subclass of F04. The subclasses F01L, F01M, F01P do not cover pump or machine features per se.
This place does not cover:
Examples of places where the subject matter of this place is covered when specially adapted, used for a particular purpose, or incorporated in a larger system:
Engine fuel injection pumps |
Attention is drawn to the following places, which may be of interest for search:
Rotary-piston or oscillating piston machines for elastic fluids | |
Cyclically operating valves for machines or engines | |
Lubrication of machines or engines in general | |
Cooling of machines or engines in general | |
Internal combustion piston engines or combustion engines in general | |
Fuel injection apparatus | |
Positive-displacement engines driven by liquids | |
Crankshafts, crossheads, connecting-rods | |
Flywheels | |
Gearings for interconverting rotary motion and reciprocating motion in general | |
Pistons, piston-rods, cylinders, in general | |
Means for thermal insulation in general | |
Refrigeration machines, plants or systems | |
Ion pumps | |
Electrodynamic pumps |
Reciprocating piston type:
Documents indicating that the machine may be operated both as a hydraulic engine and/or as a pump are classified in F03C and in F04B.
In cases were pump/compressor control or control parameters thereof are of special interest, the document should be classified by using the corresponding Indexing Code of F04B.
In cases were a specific liquid handled by the pump is of special interest, the document should be classified by using the corresponding Indexing Code of F04B 15/00.
In cases were a material or material properties are of special interest, the document should be classified by using the corresponding Indexing Code of F05C.
In this place, the following terms or expressions are used with the meaning indicated:
Pump | Device for continuously raising, forcing, compressing, or exhausting fluid by mechanical means |
Machine | Device that could equally be both an engine and a pump and not a device which is restricted to an engine or one which is restricted to a pump |
Positive displacement pumps | Pumps using pistons or other mechanical members to displace a working fluid in a working chamber, the dynamic effect on the fluid being of minor importance |
Positive displacement engines | The energy of a working fluid is transformed into mechanical energy, in which variations of volume created by the working fluid in a working chamber produce equivalent movement of mechanical members, e.g. pistons transmitting the energy, the dynamic effect of the fluid being of minor importance |
Oscillating piston machine | Positive-displacement machine in which a fluid-engaging, work-transmitting member oscillates, e.g. a vane piston swinging back and forth about a fixed axis |
Reciprocating piston | A fluid-engaging, work-transmitting member of an reciprocating-piston type machine or pump that slides alternately back and forth usually along a straight line or path |
Rotary piston | A fluid engaging, work-transmitting member of a rotary-piston machine or pump that can completely rotate about a fixed axis or about an axis moving along a circular or similar orbit when operating, e.g. rotor having vanes or teeth |
Free-piston machine | A linear , "crankless" reciprocating piston machine in which the piston motion is not controlled by a crankshaft but determined by the interaction forces from the fluid pressure in the working chamber, a rebound device (e.g. a piston in a closed cylinder) and a load device (e.g. a gas compressor or a linear alternator) |
Rotary piston machine | Positive-displacement machine in which a liquid-engaging, work-transmitting member rotates about a fixed axis or about an axis moving along a circular or similar orbit, e.g. machine with a rotor having vanes or teeth |
Cooperating members | The "oscillating piston" or "rotary piston" and another member, e.g., the working-chamber wall, which assists in the pumping action or machine's action |
Movement of the cooperating members | To be interpreted as relative, so that one of the "cooperating members" may be stationary, even though reference may be made to its rotational axis, or both may move |
Teeth or tooth equivalents | Includes lobes, projections or abutments |
Internal axis type | The rotational axes of the inner and outer co-operating members remain at all times within the outer member, e.g., in a similar manner to that of a pinion meshing with the internal teeth of a ring gear |
Working fluid | Driven fluid in a pump or driving or driven liquid in a machine. The working fluid can be in a compressible, gaseous state, e.g. steam, called elastic fluid, a liquid state, or a state where there is coexistence of elastic fluid and liquid state |
In patent documents, the following words/expressions are often used as synonyms:
- "piston" and "plunger";
- "membrane" and "diaphragm".
This place covers:
Pumps for liquids defined by the number of cylinders (e.g. having two or more cylinders) or by the arrangement of the cylinders (e.g. radial piston pumps with cylinders in star or fan arrangement, or axial piston pumps with cylinders parallel or inclined with respect to a main shaft).
This place does not cover:
Machines or pumps with pistons coacting within one cylinder |
Examples of places where the subject matter of this place is covered when specially adapted, used for a particular purpose, or incorporated in a larger system:
Pumps for raising fluids from great depths |
Attention is drawn to the following places, which may be of interest for search:
Fluid-driven pumps | |
Compressor, i.e. pumps for elastic fluids | |
Control of reciprocating machines or pumps in general | |
Reciprocating-piston engines |
If a document concerns embodiments which are covered by several subgroups dependent on a higher hierarchy head group, e.g. valve types F04B 1/0452, the following classification rules apply:- the specific technical information relevant for some of the subgroups is classified in all of said subgroups;- if generic technical information common to all of the subgroups is disclosed and only schematic embodiments are represented, then the document is classified in the higher hierarchy head group.
Attention is drawn to the following places, which may be of interest for search:
Disconnecting pistons from the actuated cam in general |
This place does not cover:
Sealing means for piston | |
Stoffing boxes |
This place does not cover:
Machines or pumps with piston coacting with rotating cylinder block |
This place does not cover:
Control with cylinder blocks and actuating cams rotating together |
Attention is drawn to the following places, which may be of interest for search:
With cylinder blocks and actuating cams rotating together |
Attention is drawn to the following places, which may be of interest for search:
Control thereof |
This place covers:
Pumps for liquids, wherein two or more pistons reciprocate within one cylinder, or wherein one piston forms the cylinder of a further piston.
Examples of places where the subject matter of this place is covered when specially adapted, used for a particular purpose, or incorporated in a larger system:
For raising fluid from great depths |
This place covers:
Pumps for liquids, with stepped pistons or with double-acting pistons.
Examples of places where the subject matter of this place is covered when specially adapted, used for a particular purpose, or incorporated in a larger system:
For raising fluid from great depths |
This place covers:
Valves and distribution members being mounted in or adapted for pumps, wherein the valves are mechanically driven, actuated by electro-magnetic means, fluid actuated, or by reciprocating pistons.
Examples of places where the subject matter of this place is covered when specially adapted, used for a particular purpose, or incorporated in a larger system:
Pumps for raising fluids from great depths |
This place covers:
Pumps for liquids driven by mechanical means, e.g. cams, eccentrics or other means or by fluid means, e.g. hydraulically driven or pneumatically driven. In this group are also classified pumps being manually driven by a user.
Examples of places where the subject matter of this place is covered when specially adapted, used for a particular purpose, or incorporated in a larger system:
For raising fluid from great depths |
If a document concerns embodiments which are covered by several subgroups dependent on a higher hierarchy head group, e.g. mechanical means F04B 9/02, the following classification rules apply:- the specific technical information relevant for some of the subgroups is classified in all of said subgroups;- if generic technical information common to all of the subgroups is disclosed and only schematic embodiments are represented, then the document is classified in the higher hierarchy head group.
This place covers:
Pumps for liquids comprising means for preventing problems occurring with pulsation, vibration and/or cavitation.
Examples of places where the subject matter of this place is covered when specially adapted, used for a particular purpose, or incorporated in a larger system:
For raising fluid from great depths |
This place covers:
Pumps for liquids specially adapted for dosing purposes or for mixing two or more fluids.
Examples of places where the subject matter of this place is covered when specially adapted, used for a particular purpose, or incorporated in a larger system:
Pumps for raising fluid from great depths | |
Arrangements of pumps for transferring liquids from bulk storage containers or reservoirs into vehicles or into portable containers |
This place covers:
Pumps specially adapted for pumping e.g. viscous fluids, fluids at high temperatures, corrosive fluids or cryogenic fluids.
Various types of pumps for liquids and for elastic fluids not provided for in other groups, e.g. pumps for corrosive fluids or for cryogenic fluids.
Examples of places where the subject matter of this place is covered when specially adapted, used for a particular purpose, or incorporated in a larger system:
For raising fluid from great depths |
This place covers:
Pumps for liquids driven by specific engines or other driving means, such as e.g. electric motors, piezoelectric means, solar means, wind energy, or combustion engines. In this group are also classified mobile pumping systems, e.g. pumps on vehicles.
Examples of places where the subject matter of this place is covered when specially adapted, used for a particular purpose, or incorporated in a larger system:
For raising fluid from great depths |
This place covers:
In this group are classified various types of pumps not provided for in other groups, such as e.g. free-piston pumps, micropumps, pumps with movable cylinders, pumps for storage containers, scoop devices adhesion type pumps, or pumps using the effect of heat expansion.
This place does not cover:
Micropumps having plate-like flexible members. |
Examples of places where the subject matter of this place is covered when specially adapted, used for a particular purpose, or incorporated in a larger system:
For raising fluid from great depths |
Examples of places where the subject matter of this place is covered when specially adapted, used for a particular purpose, or incorporated in a larger system:
Arrangements of pumps for transferring liquids from bulk storage containers or reservoirs into vehicles or into portable containers |
This place covers:
Pumps for liquids combined with reservoirs or with other fluid pumps.
This place does not cover:
Pumps characterised by combination with, or adaptation to, specific driving engines or motors |
Examples of places where the subject matter of this place is covered when specially adapted, used for a particular purpose, or incorporated in a larger system:
For raising fluid from great depths |
This place covers:
Pumps for elastic fluids, e.g. gas or steam, having more than one pumping stage, e.g. with two or more cylinders or with stepped pistons.
Examples of places where the subject matter of this place is covered when specially adapted, used for a particular purpose, or incorporated in a larger system:
For raising fluid from great depths |
This place covers:
Pumps for elastic fluids, e.g. gas or steam, defined by the number of cylinders, e.g. having two or more cylinders, or by the arrangement of the cylinders, e.g. radial piston pumps with cylinders in star or fan arrangement, or axial piston pumps with cylinders parallel or inclined with respect to a main shaft.
Details relating to control systems and methods for pumps for elastic fluids , e.g. gas or steam, defined by having cylinders coaxial with, or parallel or inclined to, main shaft axis.
This place does not cover:
Multi-stage pumps specially adapted for elastic fluids |
Examples of places where the subject matter of this place is covered when specially adapted, used for a particular purpose, or incorporated in a larger system:
Pumps for raising fluid from great depths |
Attention is drawn to the following places, which may be of interest for search:
Control of reciprocating machines or pumps in general |
If a document concerns embodiments which are covered by several subgroups dependent on a higher hierarchy head group, e.g. valve types classified in F04B 27/0451; crankcase pressure control classified in F04B 27/1804, the following classification rules apply:- the specific technical information relevant for some of the subgroups is classified in all of said subgroups;- if generic technical information common to all of the subgroups is disclosed and only schematic embodiments are represented, then the document is classified in the higher hierarchy head group.
This place covers:
Pumps for elastic fluids, e.g. gas or steam, being characterised by rotatable cylinders.
Examples of places where the subject matter of this place is covered when specially adapted, used for a particular purpose, or incorporated in a larger system:
For raising fluid from great depths |
This place covers:
Pumps for elastic fluids, e.g. gas or steam, being of free-piston type.
This place does not cover:
Muscle-driven pumps in which the stroke is not defined by gearing |
Examples of places where the subject matter of this place is covered when specially adapted, used for a particular purpose, or incorporated in a larger system:
Pumps for raising fluid from great depths | |
Free-piston combustion engines, free-piston gas generators |
Attention is drawn to the following places, which may be of interest for search:
Free-piston pumps for liquids | |
Free-piston engines |
This place covers:
Pumps for elastic fluids specially adapted for manual operation and for inflating tyres.
Examples of places where the subject matter of this place is covered when specially adapted, used for a particular purpose, or incorporated in a larger system:
For raising fluid from great depths |
Attention is drawn to the following places, which may be of interest for search:
Arrangements of tyre-inflating valves to tyres or rims |
This place covers:
Pumps for elastic fluids, e.g. gas or steam, driven by specific engines or other driving means, such as e.g. electric motors, floating elements, steam engines, or combustion engines; Mobile pumping systems, e.g. compressors on vehicles.
Examples of places where the subject matter of this place is covered when specially adapted, used for a particular purpose, or incorporated in a larger system:
For raising fluid from great depths |
This place covers:
Various types of pumps for elastic fluids, e.g. gas or steam, not provided for in other groups, such as e.g. vacuum pumps evacuating by absorption means, vacuum pumps evacuating by thermal means, pumps for very high or very low pressure, or pumps for wet gases.
Examples of places where the subject matter of this place is covered when specially adapted, used for a particular purpose, or incorporated in a larger system:
For raising fluid from great depths |
Attention is drawn to the following places, which may be of interest for search:
Absorption or adsorption in general | |
For gas-filled discharge tubes |
Attention is drawn to the following places, which may be of interest for search:
Cold traps |
This place covers:
Various components adapted for pumps for elastic fluids, e.g. gas or steam, such as e.g. piston means, pulsation damping means, lubrication means, cooling means, filtering means, compressor valves, compressor casings.
This place does not cover:
Of machines or engines in general |
Examples of places where the subject matter of this place is covered when specially adapted, used for a particular purpose, or incorporated in a larger system:
Pumps for raising fluid from great depths |
Attention is drawn to the following places, which may be of interest for search:
For controlling |
This place covers:
Lubrication of pumps for liquids and elastic fluids.
Attention is drawn to the following places, which may be of interest for search:
Cooling of machines or engines in general |
Attention is drawn to the following places, which may be of interest for search:
Casings for machines or engines in general |
This place covers:
Pumps for elastic fluids, e.g. gas or steam, combined with reservoirs or with other fluid pumps.
This place does not cover:
Free-piston pumps specially adapted for elastic fluids or systems incorporating such pumps | |
Piston pumps specially adapted for elastic fluids and characterised by the driving means to their working members, or by combination with, or adaptation to, specific driving engines or motors, not otherwise provided for |
Examples of places where the subject matter of this place is covered when specially adapted, used for a particular purpose, or incorporated in a larger system:
For raising fluid from great depths |
This place covers:
Pumps for liquids and for elastic fluids having flexible working members, such as diaphragms, tubular flexible members or pumps with peristaltic action; Micropumps having flexible working members.
This place covers:
Pumps having flexible working members and which are specifically adapted for elastic fluids. The flexible working members may be bellows, diaphragms or tubular flexible members.
This place covers:
Pumps specifically adapted for raising fluids from great depths, such as wellbore pumps.
Attention is drawn to the following places, which may be of interest for search:
Methods or apparatus for obtaining oil, gas, water, soluble or meltable materials or a slurry of minerals from wells |
This place covers:
Control systems and methods for pumps for liquids and for elastic fluids.
If a document concerns embodiments which are covered by several subgroups dependent on a higher hierarchy head group, e.g. variable length of piston stroke classified in F04B 49/12, the following classification rules apply:- the specific technical information relevant for some of the subgroups is classified in all of said subgroups;- if generic technical information common to all of the subgroups is disclosed and only schematic embodiments are represented, then the document is classified in the higher hierarchy head group.
Attention is drawn to the following places, which may be of interest for search:
Controlled electrically |
Attention is drawn to the following places, which may be of interest for search:
Controlled electrically |
This place covers:
Systems and methods for testing pumps for liquids and for elastic fluids.
This place covers:
In this group are classified various components adapted for pumps for liquids and for elastic fluids, e.g. piston means, pulsation and noise damping means, lubrication means, cooling means, filtering means, compressor valves, housings or casings.
Attention is drawn to the following places, which may be of interest for search:
Cooling of machines or engines in general |
Attention is drawn to the following places, which may be of interest for search:
Lubricating of machines or engines in general |
This place covers:
Pump control parameters for pumps for liquids and elastic fluids.
Attention is drawn to the following places, which may be of interest for search:
Piston machines or pumps in which the valving is performed by the pistons and cylinders being relatively reciprocated and rotated |
This place covers:
Motor control parameters of pumps for liquids and elastic fluids.
This place covers:
Fluid parameters relating to pumps for liquids and elastic fluids.
This place covers:
External parameters relating to pumps for liquids and elastic fluids.