A pump comprises: a housing: a stator disposed inside the housing; a pump gear which is disposed to correspond to the stator and which includes an external gear and an internal gear; and a magnet disposed on the external gear, wherein the magnet includes a first outer circumferential surface, the external gear includes a second outer circumferential surface, and the curvature of the first outer circumferential surface can be smaller than the curvature of the second outer circumferential surface.

An electric pump provided with a pump unit configured to discharge working oil by being rotationally driven by an electric motor includes: a drive shaft configured to transmit rotational driving force from the electric motor to a rotor of the pump unit; a rotation-detection shaft provided coaxially with the drive shaft, the rotation-detection shaft being configured to be rotated together with the rotor; and a rotation detector unit configured to detect rotation of the rotation-detection shaft. The rotation-detection shaft has: an engagement portion configured to engage with the rotor; and a detection-target portion facing the rotation detector unit, and an outer diameter of the detection-target portion is set so as to be larger than an outer diameter of the engagement portion.

A displacement device including an inner rotor and an outer rotor with meshing projections. Points on each rotor trace a hypotrochoidal path relative to the other. The tips of the outer rotor projections may contact the inner rotor at Top Dead Center (TDC) and Bottom Dead Center (BDC) to form higher and lower pressure regions. Various elements may shape other elements to form seals.

A pump housing of an oil pump includes a suction port that supplies oil to a pump room, a discharge port that discharges oil from the pump room, and a seal portion that suppresses leakage of oil from the pump room to outside of the pump room. A shaft of the oil pump includes a small diameter portion and a large diameter portion having different diameters, the small diameter portion is connected to the inner rotor, and the shaft and the inner rotor integrally rotate. The seal portion is in contact with a side surface of the inner rotor extending in a diameter direction of the shaft, and also extends to a region in the diameter direction on an inner side smaller than the large diameter portion in the diameter direction.

An oil pump includes: a shaft member; an inner rotor configured to rotate integrally with the shaft member; an outer rotor forming a rotor chamber into which oil is sucked from a suction passage and from which the oil is discharged toward a discharge passage, between the inner rotor and the outer rotor; a body member having a recess-shaped housing chamber in which each rotor is housed so as to be rotatable about an axis; and a cover member attached so as to close the housing chamber. The rotor chamber has first and second suction ports through each of which the oil to be sucked from the suction passage passes. The oil pump includes a straightening member branching the suction passage from a main path to the first suction port side and the second suction port side.

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.

Machine provided with a machine element (2) and an oil pump (4) and a motor (3) to drive the machine element (2) and the oil pump (4), whereby the oil pump (4) is provided with a shaft (13) with a rotor (12), whereby the oil pump (4) is provided to pump oil from an oil reservoir (5) via an inlet channel (8) to nozzles that lead into the motor (3) and/or machine element (2) to lubricate and/or cool one or more bearings or other machine components, characterized in that in the inlet channel (8), near the oil pump (4) a dam (16) is provided that is higher than the height (A) of the central axis (18) of the shaft (13) of the oil pump (4) minus the smallest diameter (B) of the rotor (12) of the oil pump (4) divided by two.

A pump having an adjustable delivery volume, including: a pump housing featuring a delivery chamber which includes a delivery chamber inlet for a fluid and a delivery chamber outlet for the fluid; a delivery member, which can be rotated within the delivery chamber, for delivering the fluid; an adjusting device featuring a setting structure, which is mounted such that it can move back and forth within the pump housing in order to adjust the delivery volume of the pump, and a helical spring for applying a spring force, which acts in a setting direction, to the setting structure, wherein the windings of the helical spring are enclosed by an envelope lying on the outside of the helical spring wherein the cross-sectional area of the envelope as measured transversely with respect to the longitudinal direction of the spring changes progressively in the longitudinal direction of the spring.

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.

The present disclosure provides a motor unit and a motor-control device using the same, wherein the motor includes a motor element, a housing and a bearing. The motor element is contained within the housing, the bearing is fastened on a lower-edge portion of the housing and protrudes therefrom. The motor-control device includes a main body, and the motor unit mounted on the main body.