A gerotor pump assembly, and a system and method for operating a gerotor pump assembly, result in a lubrication strategy for operating in a loss-of-prime mode. An inner drive gear may be rotated in a first direction and in a second opposite direction about an axis of rotation. The inner drive gear has a number of projections extending outwardly therefrom. An outer driven gear surrounds the inner drive gear and defines a number of recessions along an inner surface configured to engage with the projections of the inner drive gear. The outer driven gear and the inner drive gear further define at least one dynamically-changing fluid cavity therebetween. The inner drive gear and the outer driven gear define an oil transfer volume clearance between a projection and a recession in a fully engaged position. Oil is maintained within the oil transfer volume clearance as the inner drive gear is rotated.

A variable oil pump includes a pump housing, an oil pump rotor accommodated in the pump housing, an adjustment member accommodated in the pump housing and configured to adjust a discharge amount of oil discharged from the oil pump rotor by displacing in a state where the adjustment member holds the oil pump rotor from an outer circumferential side in such a manner that the oil pump rotor is rotatable, and a guide portion including a guide hole provided at the adjustment member and a pin provided at the pump housing and engaging with the guide hole. The guide portion is configured to guide a displacement of the adjustment member relative to the pump housing by allowing the guide hole and the pin to engage with each other. The variable oil pump includes a drain passage configured to drain oil accumulated in the guide hole.

An aircraft engine having an oil circuit and a transmission that can be supplied with oil via the oil circuit. Oil fed to the transmission can be directed out of the transmission into an oil reservoir, from which oil can be introduced directly back into the transmission via a hydraulic line path. According to the invention, the oil fed to the oil reservoir can only be fed to the hydraulic line path below a defined filling level of the oil reservoir. When the defined filling level of the oil reservoir is reached, oil can also be introduced into a further hydraulic line path.

An electric oil pump includes a motor part having a shaft; a pump part that is driven by the motor part via the shaft and discharges oil; and a control part configured to control an operation of the motor part. The motor part includes a rotor, a stator, and a motor housing in which the rotor and the stator are accommodated. The pump part includes a pump rotor attached to the shaft and a pump housing having a housing part in which the pump rotor is accommodated. The control part includes an electronic component and a board having a surface on which the electronic component is mounted. The board is disposed outside the stator in a radial direction and within a range of the motor part in the axial direction, and the surface of the board is disposed to face the stator and extends in the axial direction.

An electric oil pump includes a motor part having a shaft; a pump part that is driven by the motor part via the shaft and discharges oil; and a control part configured to control an operation of the motor part. The motor part includes a rotor, a stator, and a motor housing. The pump part includes a pump rotor and a pump housing having a housing part. The control part includes a plurality of electronic components and a board. The motor housing has a cylindrical part in which the rotor and the stator are accommodated, a plurality of heat dissipating fins that extend from the cylindrical part, and a fin support that supports the heat dissipating fins. The heat dissipating fins are disposed at intervals in the axial direction. The fin support has an inter-fin through-hole between a pair of heat dissipating fins adjacent in the axial direction.

A hybrid oil pump for a vehicle with an engine. The hybrid oil pump includes an oil pump unit with a pump shaft, a mechanical drive to drive the oil pump unit in a mechanical driving mode, an electrical drive to drive the oil pump unit in an electrical driving mode, a switchable clutch arranged between the motor shaft and the pump shaft, and a freewheel clutch to automatically couple the mechanical drive with the pump shaft when a rotational speed of the mechanical drive is higher than a rotational speed of the electric motor. The oil pump unit pumps pressurized oil to a vehicle component. The mechanical drive is mechanically connected to and driven by the engine. The electrical drive includes an electric motor and a motor shaft. The switchable clutch mechanically disengages the electrical drive from the oil pump unit in the mechanical driving mode.

In a vehicle power unit having an internal combustion engine, a pair of power transmission gears for transmitting rotation of a crank shaft to a balancer shaft is arranged between a crankcase and a crankcase cover, and a fluid pump is provided on a power transmission gear shaft supporting a power transmission gear, by which the backlash between the crank shaft and the balancer shaft is reduced and the friction and the noise of the gears are restrained while achieving downsizing of the gears of the crank shaft and the balancer, weight reduction and downsizing of the power unit.

An engine power unit for a vehicle has a crankcase made up of tow left and right crankcase members, and a lubricant feed pump disposed in one crankcase member in such a fashion that one side surface of pump rotors of the feed pump lies on the mating surface of the crankcase members. The feed pump is mounted on one end of the shaft of the feed pump while a drive gear for rotating the shaft is disposed on the opposite end of the shaft. A lubricant oil filter to which oil is delivered from the feed pump is disposed on the other crankcase member. Thus, the structure for supplying lubricating oil is simplified, and the power unit is reduced in size in its entirety.

A delivery device for a motor vehicle for delivering oil from an oil sump to a lubricating oil circuit of internal combustion engine has, as an oil pump, a double-stroke vane-type pump with positive guidance of vanes. A direct drive of the vane-type pump by means of the internal combustion engine is configured for an operating point P2. An increased or reduced oil demand is compensated by means of an activatable electric drive. A compact oil pump of very small dimensions may thus be used.

In a variable displacement oil pump, a drain chamber 36 partitioned with respect to first and second control oil chambers 31, 32 and which serves to generate a biasing force in a concentric direction based on a pump drain pressure directly introduced from a drain port 22a is interposed between first control oil chamber 31 which serves to generate a biasing force in the concentric direction in which a volume variation quantity of a plurality of pump chambers PR for a cam ring 15 based on a control pressure as a main gallery pressure introduced from an internal combustion engine and second control oil chamber 32 which serves to generate the biasing force in an eccentric direction in which the volume variation quantity of the plurality of pump chambers PR is increased for cam ring 15 based on the control pressure.