A sliding vane pump includes a fixed housing defining inlet and outlet ports and a sliding housing defining a cylindrical cavity and configured to slide within the fixed housing. The fixed housing and the sliding housing define a gap therebetween. A rotor is configured to rotate within the cylindrical cavity and has a plurality of vanes configured to seal against an inner circumferential wall of the cylindrical cavity to define a plurality of pumping chambers. A seal is located in the gap disposed between the fixed housing and the sliding housing to split the gap into first and second compensation chambers. The first chamber is fluidly connected to a first pumping chamber of the plurality of pumping chambers and the second chamber is connected to a second pumping chamber of the plurality of pumping chambers.

A screw pump with a housing; a housing cover; at least one idler screw held in a bore in the housing; and a bushing arranged on the housing cover with a receiving space bounded by a cylindrical flange, into which one end of the idler screw engages; wherein the bushing has an opening in its base, through which a fluid, supplied by a feed channel in the cover, can be supplied from the end opposite the idler screw under pressure to the end surface of the idler screw, wherein the bushing engages with radial play in a receptacle in the cover and comprises a radial flange, by which it is supported axially on the housing; and wherein at a least certain part of the ring-shaped flange of the bushing engages in the bore and is accommodated therein with play.

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 seal tube assembly of a pump system is provided. The seal tube assembly includes a single seal tube having a first axial end sealably coupled to a first vane pump and a second axial end sealably coupled to a second vane pump. The single seal tube includes transverse contact surfaces at the first axial end and transverse contact surfaces at the second axial end. The single seal tube is formed to define a first seal tube cavity at the first axial end and a second seal tube cavity at the second axial end.

An electric oil pump apparatus includes an electric oil pump including a housing main body that accommodates a motor and a pump driven by the motor, a flange portion formed on the housing main body, and a control circuit case for accommodating a control circuit, and a base plate attached to the electric oil pump. The base plate includes an annular main body fixed to the housing main body, and a sealing member located between the annular main body and the housing main body. The annular main body includes a first surface located on one side, a second surface located on the other side, a first through hole for passing the housing main body therethrough, and an annular stepped portion configured to accommodate the sealing member, and formed along an inner edge of the first through hole. The first surface of the base plate is opposed to the flange portion.

A pump bearing for use in a gear pump including a top face, a side face perimetrically surrounding the top face, a bottom face opposed to the top face, a first bearing bore projecting from the top face to the bottom face defining an axis and configured to contain a drive-side shaft, and a groove within the side face located between the top face and the bottom face a variable depth in a direction perpendicular to the axis configured to a receive seal.

A cartridge vane pump includes: a side plate brought into contact with first end surfaces of the rotor and the cam ring; a cover brought into contact with second end surfaces of the rotor and the cam ring, the cover attached to the body; and an O-ring provided in an outer circumference of the side plate, the O-ring being configured to seal a gap between the outer circumference of the side plate and an inner circumference of the body. The side plate has: a first flange portion configured to restrict movement of the O-ring towards the rotor side; a second flange portion configured to restrict movement of the O-ring towards an opposite side from the rotor. The first flange portion is formed to be able to compress the O-ring with the body in an axial direction of the driving shaft.

A pump bearing including a top face, a side face peripherally surrounding the top face, a bottom face opposed to the top face, a first bearing bore projecting from the top face to the bottom face, an edge defined where the top face meets the side face, and an asymmetric pressure balance groove defined within a portion of the edge of the top face and the side face defining first depth from the top face.

A pump bearing for use in a gear pump including a top face, a side face perimetrically surrounding the top face, a bottom face opposed to the top face, a first bearing bore projecting from the top face to the bottom face defining an axis and configured to contain a drive-side shaft, and a groove within the side face located between the top face and the bottom face a variable depth in a direction perpendicular to the axis configured to a receive seal.

A pump bearing including a top face, a side face peripherally surrounding the top face, a bottom face opposed to the top face, a first bearing bore projecting from the top face to the bottom face, an edge defined where the top face meets the side face, and an asymmetric pressure balance groove defined within a portion of the edge of the top face and the side face defining first depth from the top face.