CPC Definition - Subclass F04D
This place covers:
Non positive displacement pumps for liquids, for elastic fluids, or for liquids and elastic fluids, whether rotary or not having pure rotation.
This place does not cover:
Engine fuel-injection pumps | |
Ion pumps | |
Electrodynamic pumps |
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:
Aeroplane propellers |
Attention is drawn to the following places, which may be of interest for search:
Blood pumps | |
Obtaining oil, gas, water from deep wells | |
Non positive displacement machines or engines | |
Pumping cooling air or liquid coolants | |
Machines or engines for liquids | |
Wind motors | |
Combinations of non-positive displacement pumps with other pumps; Positive displacement machines for fluids; Pumps | |
Rotary-piston, or oscillating piston, positive displacement machines for fluids | |
Bearings | |
Sealings | |
Central heating systems | |
Air conditioning, Ventilation |
As a general rule a complete classification will contain at least one class out of the 2 first main parts which would specify the type of pump concerned, combined with at least one class out of the main group F04D 29/00.
In cases were a "Details, component, parts, or accessories" has to be classified which can be used in a number of different types of pumps which would be covered by different sub groups, only the relevant F04D 29/00 sub group class should be given.
Care should be taken when classifying compressors used in combination with gas turbines. Classification in F04D when compressor details are predominant. Classification in F01D when the integration or the fluid connection to the turbine or its combustion chamber are involved
This subclass is generally subdivided in 3 main parts:
- Non-positive displacement pumps for non-elastic fluids: F04D 1/00 - F04D 15/029
- Non positive displacement pumps for elastic fluids: F04D 17/00-F04D 27/0292
- Details, component, parts, or accessories: F04D 29/00 - F04D 29/708
In the part related to "Details, component, parts, or accessories" i.e. main group F04D 29/00 each sub group is subdivided in two further subgroups, one for elastic fluids and another on for non elastic fluids. By way of example: F04D 29/02 has a subgroup F04D 29/023 covering the elastic fluids, and another subgroup F04D 29/026 covering the non elastic fluids.
In this place, the following terms or expressions are used with the meaning indicated:
Engine | means a device for continuously converting fluid energy into mechanical power. Thus, this term includes, for example, steam piston engines or steam turbines, per se, or internal-combustion piston engines, but it excludes single-stroke devices |
Pump | means a device for continuously raising, forcing, compressing, or exhausting fluid by mechanical or other means. Thus, this term includes fans or blowers |
Machine | means a device which could equally be 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 | means the way 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 displacements of the mechanical member transmitting the energy |
Non-positive displacement | means the way the energy of a working fluid is transformed into mechanical energy, by transformation of the energy of the working fluid into kinetic energy, and vice versa |
Rotary-piston machine | means a positive-displacement machine in which a fluid-engaging work-transmitting member rotates about a fixed axis or about an axis moving along a circular or similar orbit. This definition applies also to engines and pumps |
This place covers:
Radial and mixed flow type pumps for non elastic fluids
This place does not cover:
Shear force pumps | |
Adaptation to specific liquids | |
Priming of pumps |
In patent documents the following expressions/words "helico centrifugal flow", "mixed flow" and "diagonal flow" are often used.
This place covers:
Axial flow type pumps for non elastic fluids.
Attention is drawn to the following places, which may be of interest for search:
Conveyors | |
Archimedes screw pumps |
This place covers:
Shear force pumps and pumps with circumferential or transverse flow, also shear force pumps, although they are generally of radial type.
In this place, the following terms or expressions are used with the meaning indicated:
Shear force pump | a pump where the energy is transferred to the liquid by friction forces |
In patent documents the following expressions/words "circumferential flow pump", "side channel pump", "regenerative pump", "peripheral flow pump" and "vortex flow pump" are often used.
This place covers:
Adaptations which make a pump suitable for a specific liquid.
Attention is drawn to the following places, which may be of interest for search:
Pumping specific fluids in general |
In general classification is combined with a sub group in the F04D 29/00 group
This place covers:
All adaptations of a pump in order to prime the pump, to avoid vapor lock or to avoid loss of prime
This place covers:
Any rotary non-positive displacement which does not have radial, axial or helico centrifugal flow.
This place covers:
The combination of a pump with its drive system or its integration into a system either comprising several pumps or comprising storage systems
This place does not cover:
Control of pumps |
Attention is drawn to the following places, which may be of interest for search:
Electrical machines | |
Magnetic couplings |
This place covers:
Systems and schemes for controlling a pump, either matching the pump to the requirements of the system or avoiding harmful conditions for the pump
Attention is drawn to the following places, which may be of interest for search:
Actuators for control action |
This place covers:
Radial and mixed-flow type pumps for elastic fluids.
The centrifugal pumps for elastic fluids are subdivided into 2 main parts; in the "compressing or evacuating" sub group F04D 17/10 the compression ratio should be significant, while in the "for displacing without appreciable compression" sub group F04D 17/16 the generation of flow is predominant
In patent documents the following expressions/words "helico centrifugal flow", "mixed flow" and "diagonal flow" are often used.
This place covers:
Axial flow type pumps for elastic fluids.
This place does not cover:
Combined axial-flow and radial-flow stages | |
Pumps involving supersonic speeds in the pumped fluid |
The axial pumps for elastic fluids are subdivided into 2 main parts; in the "multistage pumps" sub group F04D 19/02 the compression ratio should be significant, while in the "fan" sub groups F04D 19/002 and F04D 19/007 the generation of flow is predominant
This place covers:
All pump for elastic fluids involving supersonic speed of pumped fluids.
This place covers:
Any rotary non positive displacement which does not have radial, axial or helico centrifugal flow, pumps adapted for conveying or for handling specific elastic fluid, and pumps with circumferential or transverse flow.
This place covers:
The combination of a pump for elastic fluids with its drive system or its integration into a system either comprising several pumps or comprising storage systems.
This place does not cover:
Pump installation control |
Attention is drawn to the following places, which may be of interest for search:
Hand held fans |
F04D 25/06 and F04D 25/08 are both used in parallel . F04D 25/06 focusses on the motor design, or the combination of motor and pump. F04D 25/08 focusses on specific design for special purposes. Both subgroups can be used in combination (e.g. a computer fan with an inside out motor and details on how the motor is cooled will get both F04D 25/0613 and F04D 25/082 classification
This place covers:
Systems and schemes for controlling a pump for elastic fluids, either matching the pump to the requirements of the system or avoiding harmful conditions for the pump, e.g. surge or stall conditions.
Attention is drawn to the following places, which may be of interest for search:
Control of flow | |
Control of pressure |
F04D 27/02 subgroup is used for ANY type of control and is thus not limited to surge or stall control
F04D 27/001 is used when the detection of pump condition is predominant (e.g. determining of surge margin, without immediate control action; mapping of pump characteristics for later use)
This place covers:
Details, component parts, or accessories of any type of pump for elastic or non elastic fluids.
Attention is drawn to the following places, which may be of interest for search:
Making blades for propellers or turbines | |
Making specific metal objects | |
Machine elements in general |
In main group F04D 29/00 each sub group is subdivided in two further subgroups, one for elastic fluids and another on for non elastic fluids. By way of example: F04D 29/02 has a subgroup F04D 29/023 covering the elastic fluids, and another subgroup F04D 29/026 covering the non elastic fluids.
However for the subgroups relating to bearing and shafts (F04D 29/04 and F04D 29/05) and rotors (F04D 29/18 and F04D 29/26) specific subgroups are provided for elastic fluids and non-elastic fluids.
Attention is drawn to the following places, which may be of interest for search:
Blades for multistage rotors of machines or engines |
Attention is drawn to the following places, which may be of interest for search:
Fixing blades to rotors; Blade roots |
Attention is drawn to the following places, which may be of interest for search:
Selecting composite materials, e.g. blades with reinforcing filaments |
This place covers:
Pumping liquids and elastic fluids at the same time, i.e. one pump handles both elastic and non elastic fluids together.
Attention is drawn to the following places, which may be of interest for search:
Obtaining oil, gas, water from deep wells |
This place covers:
Non-positive-displacement pumps with other than pure rotation. Some examples are mechanisms imitating the movement of a bird wing or a fish tale, or the movement produced by humans when using a hand fan.
This place does not cover:
Wave generators |
This place covers:
Non-positive-displacement pumps for the generation of waves.
This place does not cover:
Wave generators for baths and tubs |
Attention is drawn to the following places, which may be of interest for search:
Swimming pools |