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.

A gerotor pump includes a casing including a pumping chamber, a fixed gear being inserted into the casing and rotating at a fixed position, including a plurality of teeth formed inside a cylinder, and including at least one fluid hole at one end of the cylinder to allow a fluid to flow from the pumping chamber or into the pumping chamber, a moving gear provided inside the fixed gear and including one less number of teeth than a number of the plurality of teeth of the fixed gear and movable in an axial direction, a gear block arranged inside the fixed gear and movable in the axial direction, a gear ring arranged outside the moving gear and movable with respect to the moving gear in the axial direction, a gear ring cover provided at one end of the casing and including a hole in which the gear ring is rotated.

An electric oil pump apparatus includes a housing, an electric motor, an oil pump, a shaft, a first bearing, and a second bearing. The electric motor is housed in the housing. The oil pump is provided in the housing and positioned on a first side in an axial direction with respect to the electric motor so as to be adjacent to the electric motor, and includes a pump rotational element rotatable coaxially with a motor rotor. The motor rotor and the pump rotational element are fitted to the shaft to be rotatable together with the shaft. The first bearing is disposed on the first side with respect to the pump rotational element, and supports the shaft while allowing rotation relative to the housing. The second bearing is disposed on a second side with respect to the pump rotational element, and supports the shaft while allowing rotation relative to the housing.

An internal gear pump includes an outer rotor having internal teeth, an inner rotor rotatably disposed inside the outer rotor and having external teeth engaging with the internal teeth, and a pump housing. The pump housing includes: a holding recess rotatably holding the outer rotor and having a wall on which an outer peripheral face of the outer rotor is to slide; an inlet to take in a fluid into pump chambers defined between the inner rotor and the outer rotor; an outlet to discharge the fluid from the pump chambers; a case groove provided on the wall and to hold the fluid; and a joint groove provided on an upper land face defined between a trailing end of the inlet and a leading end of the outlet and on which the internal teeth and the external teeth are to slide.

A commutator/manifold assembly controls a flow of hydraulic fluid in a hydraulic fluid system. The assembly includes a commutator having an offset design including an inner portion eccentrically encompassed within an outer portion, and offset commutator porting to control the hydraulic flow. A manifold includes manifold ports having a straight configuration by which walls defining the manifold ports run substantially along a longitudinal axis through an entirety of the manifold. The commutator is configured to rotate to sequentially align the commutator porting with differing portions of the manifold ports to control the flow. The commutator porting includes inner ports and outer ports that are isolated from each other by a commutator seal. A commutator ring has a guiding surface that guides rotation of the commutator. The rotation of the commutator provides a timed flow through the manifold ports straight through the manifold and without any directional flow restriction.

A drive device includes a rotor, a stator, a housing including an accommodation portion to store oil, and a pump driven through a motor shaft. The pump includes an external gear fixed to an end on one side in an axial direction of the motor shaft, an internal gear surrounding a radial outside of the external gear and meshing with the external gear, a pump room accommodating the internal gear and the external gear, a suction port through which the oil is to be sucked into the pump room, and a discharge port through which the oil is to be discharged from the pump room. The housing includes an outer lid in which the pump room is provided. The outer lid includes a shaft insertion hole that penetrates the outer lid from a surface on the other side in the axial direction of the pump room to a surface on the other side in the axial direction of the outer lid, the motor shaft being inserted into the shaft insertion hole, and a support defining at least a portion of the surface on the other side in the axial direction of the pump room and at least a portion of a radially inside surface of the shaft insertion hole. The support journals the motor shaft on the radial outside of the motor shaft.

A pump, including: inner gerotor; a crankshaft; an outer gerotor; an inlet assembly with inlet ports; an outlet assembly with outlet ports; and magnetic actuators. The inner gerotor includes lobes and a central opening. The crankshaft: passes through the central opening; is rotatable about an axis of rotation; and includes a first longitudinal axis not co-linear with the axis of rotation. The outer gerotor includes recesses. The magnetic actuators are sequentially energized to create magnetic fields to displace the inner gerotor with respect to the crankshaft to: displace a first lobe out of a first recess and draw fluid through an inlet port into the first recess; and displace a second lobe into a second recess and expel second fluid out of the second recess and through an outlet port.

An example hydraulic motor comprises: a stator comprising (i) a stator body having plurality of roller pockets, wherein the stator body comprises a plurality of grooves that are longitudinally-extending, and (ii) a plurality of rollers disposed respectively in the plurality of roller pockets; a rotor having a plurality of external teeth configured to engage with the plurality of rollers of the stator, such that the plurality of rollers and the plurality of external teeth define fluid chambers therebetween configured to expand and contract as the rotor rotates within the stator; and an anti-cogging passage configured to provide pressurized fluid from at least one of the fluid chambers to at least one groove of the plurality of grooves of the stator body, such that pressurized fluid provided to the at least one groove applies a radially-inward force on a respective roller toward the rotor.

A pump includes a stator and a rotor axially between a fluid inlet section and a fluid outlet section. The stator includes a plurality of radially inwardly extending legs; and a plurality of electrical windings disposed about the radially inwardly extending legs. The attenuating circuit includes a capacitor electrically wired in parallel with each winding and at least one switch electrically connected to the capacitor. During energization of the electrical winding, the switch electrically connects the capacitor to an electrical ground and the electrical power source creates a voltage in the capacitor. Following a de-energization of the plurality of electrical windings, the switch isolates the capacitor from the electrical ground and the capacitor discharges the voltage through the electrical winding, creating a decaying oscillating current that attenuates residual magnetization in the winding.

A pump device includes a housing, a pump element, and an on-off valve. The housing includes a suction passage defining a suction port at an upstream end, a discharge passage defining a discharge port at a downstream end, and a return passage returning a part of a fluid flowing through the discharge passage to midway of the suction passage. The pump element is accommodated in the housing and rotates around a predetermined axis to suck, pressurize, and discharge a fluid. The on-off valve opens and closes the return passage. In the suction passage upstream of an opening at which the return passage is opened to the suction passage, the housing includes a directional wall which directs a flow of a suction fluid sucked into the suction passage from the suction port to divert from a flow of a return fluid returned from the return passage.