A hydraulic gerotor pump for an automatic transmission may comprise a housing and a gear set rotatably disposed within the housing. The gear set may comprise an inner gear and an outer gear having radially opposed intermeshing teeth that together define a plurality of circumferentially disposed variable volume pumping chambers therebetween. The housing may be made of a first aluminum-based material, and the inner gear and the outer gear of the gear set may be made of a second aluminum-based material. The linear coefficient of thermal expansion of the first aluminum-based material may be substantially the same as that of the second aluminum-based material.

A gear pump includes: an inner rotor having external teeth; an outer rotor having a tubular inner housing portion in which the inner rotor is rotatably housed in an eccentric state, and internal teeth meshing with the external teeth; a first core having a tubular rotor housing portion in which the inner and outer rotors are housed, and a flange portion projecting radially outward from a tube wall of the rotor housing portion; a board-shaped second core having a contact portion in contact with the flange portion in an axial direction, and closing an opening of the rotor housing portion; and a housing opposing the second core and made of a resin. A gap is formed between opposing surfaces of the second core and the housing in a state where the flange portion is in contact with the contact portion and the housing opposes the second core.

A gear pump includes gears received within a housing defining an inlet, an outlet and end plates. The gears have shaft portions on each of two sides of each of the two gears. The shaft portions are mounted in journal bearings. The journal bearings each have a gear side face adjacent one of the two gears. A remote face is on a remote side of the journal bearing remote from each of the two gears. There is a plurality of heat pipes in at least one of the journal bearings. The heat pipes move heat from the gear face of the at least one of the journal bearings to the remote face. The plurality of heat pipes is enclosed by the housing, and extend generally in an axial direction from an end adjacent the gear face to an end adjacent the remote face. A fuel supply system is also disclosed.

Provided is a hydraulic orbital machine and a method of adjusting a hydraulic orbital machine comprising a first and a second lobed disk which rotate eccentrically about a rotation axis and within respective rotors; the machine is characterized by the fact that it has adjustment means designed to mutually angularly offset the angles at which, when the machine is at a standstill, the chambers defined between the lobed disks and the stator have minimum volume.

A rotary, self-priming, positive displacement pump is described. The pump may include a pump housing including an inlet and an outlet, a pump chamber including an upper wall, a lateral wall, and a floor, first and second rotary impellers in the pump chamber, and a pair of gears each secured to the first and second rotary impellers, and a pressure relief feature operable to relieve pressure developing in a relatively high pressure zone of the pump chamber. The gears mesh with each other to ensure that the vanes do not contact one another during rotation. The pressure relief feature may comprise one or more channels formed in the pump housing and/or the first and second rotary impellers. The channels connect the high pressure zone with another zone to redistribute pressure. The channels may include one continuous channel or alternatively, a plurality of unconnected channels.

A pump assembly comprising at least one housing and two gear wheels. The housing comprises at least one base plate and a cover element, which are interconnectable to form a pressure chamber. An outer circumferential surface of each of the two gear wheels has a toothing, and the gear wheels intermesh via the toothings to convey a fluid. The gear wheels are arranged along an axial direction in the pressure chamber between the base plate and the cover element. The pressure chamber is formed in the housing at least by two bores. The first gear wheel is arranged in a first bore and the second gear wheel is arranged in a second bore. Centering pins are provided for aligning the bores and the gear wheels with respect to one another, wherein all centering pins are arranged exclusively in the cover element or exclusively in the base plate.

Systems and methods are provided for pump systems that deliver optimized performance and efficiency. A method includes selecting a pump for the pump system. A maximum operating speed of the pump is determined, and its torque requirements are evaluated. A motor is selected to meet the torque requirements and a speed target is set for the motor. A speed reducer is sized for operation of the motor at the speed target and operation of the pump below the maximum speed, and the motor is coupled with the pump through the speed reducer.

A gear for a pump includes a gear body defining a root circle, and a plurality of gear teeth extending from the gear body radially outwardly of the root circle. Each of the plurality of gear teeth have a tip portion, a leading edge, a trailing edge, a circular thickness defined between the leading edge and the trailing edge, a first radially outwardly facing surface and a second radially outwardly facing surface. At least one of the first radially outwardly facing surface and the second radially outwardly facing surface includes a chamfered portion that extends from the leading edge toward the trailing edge across a portion of the circular thickness.

A rotary pump includes a housing featuring a delivery space which the housing surrounds and axially delineates on the end sides; an inner rotor rotatable in the delivery space; an outer rotor rotatable about a pump rotational axis in the delivery space and forming delivery cells with the inner rotor; and a circumferential bearing wall which mounts and surrounds the outer rotor rotatably about the pump rotation axis in radial sliding contact. The circumferential bearing wall includes multiple blind pockets which are radially open towards the outer rotor and/or the outer rotor includes multiple blind pockets which are radially open towards the circumferential bearing wall.

A split power gerotor pump includes a rotational axis, a shaft, an inner gerotor, an eccentric pocket, and an outer gerotor. The inner gerotor is rotationally fixed on the shaft, rotatable about the rotational axis, and includes n first lobes. The eccentric pocket is rotatable about the rotational axis, and includes a cylindrical bore with a center radially offset from the rotational axis and an outer surface, disposed radially outside of the cylindrical bore and arranged for direct engagement with a gear or a rotor for an electric motor. The outer gerotor includes a cylindrical outer surface installed in the cylindrical bore and n+1 second lobes.