A fluid-driven actuator system includes a fluid-driven actuator and at least one proportional control valve and at least one pump connected to the fluid-driven actuator to provide fluid to operate the fluid-driven actuator. The at least one pump includes at least one fluid driver having a prime mover and a fluid displacement assembly to be driven by the prime mover such that fluid is transferred from the pump inlet to the pump outlet. The fluid-driven actuator system also includes a controller that establishes at least one of a speed and a torque of the at least one prime mover to adjust at least one of a flow in the fluid-driven system to a flow set point and a pressure in the fluid-driven actuator system to a pressure set point and concurrently establishes an opening of the at least one proportional control valve to adjust at least one of the flow to the flow set point and the pressure to the pressure set point.

A fluid-driven actuator system includes a fluid-driven actuator and at least one proportional control valve and at least one pump connected to the fluid-driven actuator to provide fluid to operate the fluid-driven actuator. The at least one pump includes at least one fluid driver having a prime mover and a fluid displacement assembly to be driven by the prime mover such that fluid is transferred from the pump inlet to the pump outlet. The fluid-driven actuator system also includes a controller that establishes at least one of a speed and a torque of the at least one prime mover to adjust at least one of a flow in the fluid-driven system to a flow set point and a pressure in the fluid-driven actuator system to a pressure set point and concurrently establishes an opening of the at least one proportional control valve to adjust at least one of the flow to the flow set point and the pressure to the pressure set point.

A screw-spindle pump stage having a drive spindle and a running spindle which runs opposite the drive spindle and a pump housing for receiving the two screw spindles. The pump housing 16 has an offset interface with centering action, for a statically determined coupling to an electric motor. The pump housing has an offset section functioning as an abutment, which is able to be abutted against the electric motor for the application of an axial preload. At least one pressure region of the abutment section, which is close to the interface and, during a rolling, is encapsulated, and at the same time sealingly enclosed, by a sheet-metal casing, forms a rolling region of the pump, the screw spindles, together with the associated pump housing section, at least partially project from the rolling region of the pump on the suction side.

An electric gear pump comprising: a gerotor rotatable about an axis of rotation A; a support base for the gerotor; a cover which can be joined to the base; a feed duct and a delivery duct; electronic components of the control unit which are fastened on the outer surface of the cover; wherein the feed and delivery ducts are at least partly formed in the cover and comprise an axial section parallel to the axis A and a radial section parallel to the outer surface of the cover; wherein the outer surface of the cover comprises an inset portion; wherein at least a portion of the radial sections of the feed and delivery ducts is configured so as to project externally from the inset portion of the outer surface of the cover and form projecting support portions for the electronic components of the control unit.

An electrically driven gerotor pump has a gerotor which comprises a stationary outer gerotor element with an inner toothing that is axially delimited by two chamber walls, wherein each chamber-forming foot section of the inner toothing is paired with a pressure valve which is connected to the outlet. The gerotor also comprises an inner gerotor element with an outer toothing which is guided in the outer gerotor element in a circumferential manner on an eccentric section of the shaft and is mounted in, a rotatable manner so as to mesh with the inner toothing.

An electric oil pump includes a pump housing provided with an a first cavity and a second cavity; a first rotor assembly disposed in the first cavity; a stator assembly and a second rotor assembly that are disposed in the second cavity; an electric control board assembly; an isolating member, where the stator assembly is disposed at a first side of the isolating member, the electric control board assembly is disposed at a second side of the isolating member; and a wiring terminal fixedly connected to the isolating member where a connecting position between the wiring terminal and the isolating member is sealed and a connecting position between the isolating member and the pump housing is sealed. The electric oil pump can prevent working medium from affecting the performance of the electric control board assembly.

A gear pump comprises an internal gear (10), a first external gear (20) and a second external gear (30), a case member (50) having a one end side accommodation portion (52) for retaining these gears (10,20,30), an other end side accommodation portion (53) at other end side and a partition wall portion (54) therebetween, a cover member (70) and a plate member (80). A pump chamber (P) defined inside the internal gear (10) is divided into a first pump chamber (P1) which has a first intake-discharge space (L1) and a first discharge-intake space (H1), and a second pump chamber (P2) which has a second intake-discharge space (L2) and a second discharge-intake space (H2). The plate member has a first communication path (81) and a second communication path (82) between the plate member (80) and the cover member (70). The one side communication passage (57) is communicated with the first communication path (81). Two penetrating holes (82b,82c) are formed on the plate member (80). An other side communication passage (82a), which communicate the two penetrating holes (82b,82c) with each other, is formed between the plate member (80) and the cover member (70).

A gear pump comprises an internal gear (10), a first external gear (20) and a second external gear (30), a case member (50) having a one end side accommodation portion (52) for retaining these gears (10,20,30), an other end side accommodation portion (53) at other end side and a partition wall portion (54) therebetween, a cover member (70) and a plate member (80). A pump chamber (P) defined inside the internal gear (10) is divided into a first pump chamber (P1) which has a first intake-discharge space (L1) and a first discharge-intake space (H1), and a second pump chamber (P2) which has a second intake-discharge space (L2) and a second discharge-intake space (H2). The plate member has a first communication path (81) and a second communication path (82) between the plate member (80) and the cover member (70). The one side communication passage (57) is communicated with the first communication path (81). Two penetrating holes (82b,82c) are formed on the plate member (80). An other side communication passage (82a), which communicate the two penetrating holes (82b,82c) with each other, is formed between the plate member (80) and the cover member (70).

A method of manufacturing a suction pipe for a multi-compressor device having a plurality of inlets, the suction pipe comprising a primary portion and a plurality of secondary portions arranged to receive fluid from the primary portion for supplying fluid in parallel to the inlets of a multi-compressor device. The method includes designing the suction pipe by: selecting a first dimension for the primary portion of the suction pipe, calculating a first fluid velocity for fluid in the primary portion based on the first dimension, and comparing the first fluid velocity to a first predetermined threshold; selecting a second dimension for the secondary portions, calculating a second fluid velocity for fluid in the secondary portions based on the second dimension, and comparing the second fluid velocity to a second predetermined threshold; and calculating a ratio of the first fluid velocity to the second fluid velocity.

A pump assembly comprising a casing having a first pump chamber defining a first flow path and a second pump chamber or more defining a second flow path. A first pump stage includes a first shaft mounted to the casing for rotation about a rotation axis, a first pair of intermeshing gears disposed in the first flow path of the first pump chamber, the first pair of intermeshing gears interfacing each other in operative engagement, one intermeshing gear of the first pump stage mounted on the first shaft. A second pump stage includes a second shaft mounted to the casing for rotation about a rotation axis different than the rotation axis of the first shaft, a second pair of intermeshing gears disposed in the second flow path of the at least second pump chamber, the second pair of intermeshing gears interfacing each other in operative engagement, one intermeshing gear of the second pump stage mounted on the second shaft. A transmission drivingly engages the first shaft to the second shaft.