CPC Definition - Subclass F04F
This place covers:
Machines inducing a flow of a pumped fluid wherein the displaced fluid is directly in contact with an inducing fluid different from said displaced fluid.
This place does not cover:
Containers or packages with special means for dispensing liquid or semi-liquid contents by internal gaseous pressure | |
Conveying materials in bulk through troughs, pipes, or tubes by floating the materials, or by flows of gas, liquid, or foam | |
Evacuating by sorption or thermal means |
Attention is drawn to the following places, which may be of interest for search:
Rotary-piston or oscillating piston machines for liquids and elastic fluids | |
Positive-displacement engines driven by liquids | |
Positive displacement machines for liquids, or pumps in which the working-fluid is displaced by one or more reciprocating pistons or by flexible working members | |
Rotary-piston or oscillating piston machines for liquids | |
Non-positive displacement pumps | |
Fluid pressure actuators | |
Rotary fluid gearing using pumps and motors of the volumetric type for conveying rotary motion | |
Sealing in general | |
Means for thermal insulation in general | |
Dynamo electric machines |
Where combinations of pumps covered by this subclass with other pumps are defined, such combinations shall be classified in this subclass if such a system of pumps is characterised by an interaction or a specific combination of these pumps.
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 | A 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:
- "gas", "steam" and "elastic fluid"
This place covers:
Machines in which the displacing power comprises a pressurising force subjected upon a fluid other than the fluid to be pumped. The fluids may e.g. be a liquid, or a gas, e.g. steam, or also a mixture of a liquid with solids.
This place covers:
Machines where the delivery outlet for evacuation is exposed to negative fluid pressure inside a working chamber.
This place does not cover:
Siphons |
This place covers:
Jet-pumps, injectors, ejectors, or thermocompressors using the Venturi effect of a converging-diverging nozzle to convert the pressure energy of an inducing fluid to velocity energy which creates a low pressure zone that draws in and displaces a suction fluid. The inducing fluid may be a liquid, or a gas, e.g. steam. The displaced suction fluid may be a gas,e.g. steam, or a liquid, a slurry, or a dust-laden gas stream.
This place covers:
Machines inducing a flow of fluid by generating vibration in a resonatable fluid, e.g. by acoustic energy.
This place does not cover:
Loudspeakers |
This place covers:
Machines using the fluid hammer effect to develop pressure that allows a portion of the input fluid to reach a higher pressure or to be moved. The fluid hammer effect is a pressure surge or wave resulting when a fluid in motion is forced to stop or change direction suddenly, i.e. momentum change.
This place covers:
Momentum transfer pumps using a high speed jet of vapour to direct gas molecules in the pump down into the bottom of the pump and out through an exhaust, e.g. to obtain a high vacuum.
This place does not cover:
Pumps for evacuation by absorption or adsorption |
Combinations of pumps covered by this group with other pumps are only classified in this group if such other pumps are intended for preliminary pumping for diffusion pumps.
This place covers:
Machines which cause a liquid to flow above the surface of a reservoir, without pumps, powered by the fall of the liquid as it flows down a tube under the pull of gravity, and is discharged at a level lower than the surface of the reservoir.
This place covers:
Machines for exchanging pressure energy between relatively high and relatively low pressure fluid systems, wherein the fluid being may include gases (steam), liquids and pumpable mixtures of liquids and solids. The exchange of pressure energy is used for transfer of energy from one fluid stream to another.
This place does not cover:
Processes of separation using semi-permeable membranes, e.g. osmosis, reverse-osmosis |
This place covers:
Machines inducing a flow of fluid by means not provided for in other groups of this subclass, e.g. by magnetohydrodynamic effects, by electrostatic effects, or by electro-osmotic flow effects.
Attention is drawn to the following places, which may be of interest for search:
Micropumps |