A manufacturing method of an end plate of a pump that can remove a sag includes: punching a workpiece from a plate material, the workpiece being the end plate including a mounting seat including a fastener; forming a pressed trace surface by pressing an outer edge of an outer surface, when a surface, of both front and back surfaces of the punched workpiece, further from a sag formed on a cut end surface is the outer surface, and a surface, of both front and back surfaces of the punched workpiece, nearer to the sag is an inner surface. A section of the pressed trace surface disposed along an outer edge of the mounting seat is a fastening section. A section of the pressed trace surface other than the fastening section is a non-fastening section. A radial width of the fastening section is shorter than that of the non-fastening section.

A hydraulic geroller (gerotor) motor, wherein an inner rotor of a revolving group has a plurality of lobes circumferentially spaced along an outer periphery of the inner rotor, and an orbiter of the revolving group includes an orbiting ring and rounded vane portions preferably formed by roller vanes contained in inner recesses of the orbiting ring for common orbiting with the orbiting ring about the fixed longitudinal axis. The orbiter also has fixed for orbiting therewith, fluid windows for directing fluid from the fluid ports to the revolving group. The windows may be formed in an integral portion of the orbiter or in a valve plate mounted for common orbiting with the orbiting orbiter. The valve plate cooperates with a stationary commutator plate or assembly to provide an efficient arrangement for the delivery and exhaust of hydraulic pressure fluid to and from the hydraulic motor.

A vane pump includes: a rotor configured to rotate under rotational force from a rotary shaft while supporting multiple vanes and including a curved surface portion with an arc shape centered on the rotary shaft and a rotor recess depressed from the curved surface portion toward a rotation center; a cam ring disposed so as to surround the rotor and including an inner peripheral surface facing the curved surface portion of the rotor; and an inner plate disposed on one end of the cam ring in an axial direction of the rotary shaft so as to cover an opening of the cam ring and including a suction inner recess depressed toward the rotation center relative to the curved surface portion of the rotor.

A vane pump sucks the hydraulic fluid from a first inlet port and discharges it into a first outlet port and, at the same time, sucks the hydraulic fluid from a second inlet port and discharges it into a second outlet port, as a rotor having a plurality of slits housing vanes and extending in a radial manner rotates. The vane pump has a first back-pressure groove that is communicated with some of the slits to supply a back pressure from the first outlet port to the corresponding vanes and a second back-pressure groove that is communicated with other of the slits to supply a back pressure from the second outlet port to the corresponding vanes. The vanes to which the back pressure is supplied from the first back-pressure groove include the vanes in pump chambers into which the hydraulic fluid is sucked from the second inlet port.

In the two-cylinder hermetic compressor, a main bearing is disposed on one surface of a first cylinder, an intermediate plate is disposed on another surface of the first cylinder, the intermediate plate is disposed on one surface of a second cylinder, and an auxiliary bearing is disposed on another surface of the second cylinder. A shaft is constituted by a main shaft portion which has a rotor attached thereto and is supported by the main bearing, a first eccentric portion having a first piston attached thereto, a second eccentric portion having a second piston attached thereto, and an auxiliary shaft portion supported by the auxiliary bearing. A thrust receiving portion is provided on a side of the second eccentric portion facing the auxiliary shaft portion, and the auxiliary bearing is provided with a thrust surface on which the end face of the thrust receiving portion slides while contacting therewith. The thrust surface is provided with a ring groove.

In accordance with one embodiment, the gear pump comprises a first gear meshed with a second gear as well as a housing, in which the gears are supported. The housing includes a first void, which at least partly adjoins a first side surface of the first gear, and a second void, which at least partly adjoins a second side surface of the first gear. The gear pump further comprises a fluid intake channel configured to direct fluid towards the gears, wherein at least one deflector is arranged within the fluid intake such that an incident fluid flow is diverted towards the first void as well as to the second void.

A dual-cylinder two-stage variable capacity compressor is provided, including: a first cylinder, having an exhaust port connected to a first exhaust channel: a second cylinder, wherein the second cylinder is provided with a ventilating slider, and the ventilating slider is provided with a first gas transit channel and a second gas transit channel; wherein, when the ventilating slider is at a first connecting position, the first exhaust channel is connected to a suction channel in a second cylinder when the ventilating slider is at a second connecting position, the first exhaust channel is connected to a second exhaust channel. The compressor of the present disclosure can vary its own capacity, that is, the variation of the compressor's capacity can be realized by arranging a ventilating slider, which will meet the requirements of variation loads of the compressor in different seasons.

A vane pump unit assembled into a housing includes a rotor; a plurality of vanes; a cam ring; a first plate; a second plate; a connecting bar that has a first end portion fixed to the first plate, and a second end portion which protrudes from the second plate; and a clip that prevents the second plate and the cam ring from slipping out of the connecting bar. Before the clip is assembled into the housing, the retaining of the clip is positioned at least either between the first plate and the cam ring or between the second plate and the cam ring, in a place where a gap is formed. After the clip is assembled into the housing, the housing interposes the first plate, the cam ring, and the second plate in the axial direction, and the first and second plates are in close contact with the cam ring.

A screw spindle pump having a housing hi which a drive spindle and at least one running spindle having profile assemblies which engage inside each other are received, the free end of the drive spindle and the end portion of the running spindle being supported on a plate which is arranged in the housing, the plate having two faces which are inclined in opposing directions relative to each other and which form a V-shape and on which one of the spindles is supported, respectively.

A seal arrangement for a vane cell pump of cartridge design which is configured such that it can be switched into multiple flows is described. The seal arrangement comprises a first seal which is arranged so as to run around the circumference of a side plate of the vane cell pump, and a second seal which is arranged so as to run around a shaft leadthrough which is provided in the side plate. The seal arrangement is distinguished by a third seal which, apart from at least one first fluid connection, shuts off at least a second fluid connection with respect to the at least one first fluid connection within a region which is configured between the first seal and the second seal.