A rotary pump with a rotational direction which can be switched, including: a housing which has a pump space featuring an inlet into a low-pressure region of the pump space for a medium to be pumped and an outlet out of a high-pressure region of the pump space for the medium to be pumped; at least one rotor; at least one bearing for the at least one rotor; at least one sealing stay which axially faces the rotor and separates the low-pressure region from the high-pressure region in the rotational direction of the rotor; and a lubricant feed which feeds a lubricant from the pump space to at least the bearing, wherein the lubricant feed is formed in the sealing stay.

A scroll compressor includes oil in an oil storage space that is brought into direct contact with and stirred with a discharge refrigerant. The scroll compressor includes a fixed scroll, an orbiting scroll coupled to one side of the fixed scroll, and a discharge cover coupled to another side of the fixed scroll and provided with a muffler hole communicating with a refrigerant discharge space and the oil storage space.

Hydraulic devices are shown and described that can include a rotor, vanes and a ring. The rotor can be disposed for rotation about an axis. The plurality of vanes can each include a vane step. Each of the plurality of vanes can be moveable relative to the rotor between a retracted position and an extended position where the plurality of vanes work a hydraulic fluid introduced adjacent the rotor. A roller can be mounted to a tip of each of the plurality of vanes. The ring can be disposed at least partially around the rotor. The rotor can include one or more passages for ingress or egress of a hydraulic fluid to or from a region adjacent the vane step and defined by at least the rotor and the vane step.

A scroll compressor includes a first oil supply passage communicating with a first compression chamber formed between an inner circumferential surface of a fixed wrap and an outer circumferential surface of an orbiting wrap, and a second oil supply passage separated from the first oil supply passage and communicating with a second compression chamber formed between an outer circumferential surface of the fixed wrap and an inner circumferential surface of the orbiting wrap, wherein the first oil supply passage includes an oil supply guide portion provided in a thrust surface of the fixed scroll in contact with the orbiting scroll to define a part of the first oil supply passage, whereby communication between the first and second compression chambers can be prevented, thereby suppressing leakage between the compression chambers, stabilizing behavior of the orbiting scroll, and facilitating formation of the orbiting scroll.

A positive displacement pump has a casing with a central body and two closing lids, the central body being provided with two cylindrical communicating chambers, one suction pipe and one discharge pipe, and two rotors revolvingly mounted in the chambers of the central body and supported by shafts revolvingly mounted in the closing lids. The two rotors include a male rotor having only protuberances, not cavities, and a female rotor having only cavities, not teeth or protuberances.

A vacuum generation system, in particular for applications to hybrid-drive motor vehicles, comprises a vacuum pump (10) arranged to be independently driven by either an internal combustion engine (1 1) or an electric motor (12) depending on the vacuum conditions in utilizing devices (15) and the operating conditions of the internal combustion engine. A pump for use in such a system and a method of vacuum generation by using the system are also provided.

A journal bearing assembly includes a first journal bearing disposed about a longitudinal end of a gear shaft and spaced a first distance from a first axial gear face. A first fluid film location and a first hybrid pad location are annularly between an inner surface of the first journal bearing and an outer surface of the gear shaft. The first hybrid pad location circumferentially adjacent to the first fluid film location has a minimum leading edge angular location of at least about 31.0° measured relative to a first bearing flat. A first porting path provides high pressure fluid communication from a location outside the first journal bearing to the first fluid film location at or adjacent to the first hybrid pad location.

An internal gear pump includes a housing having a pump chamber in which an inner rotor and an outer rotor are arranged. A suction port in communication with a suction path and a discharge port in communication with a discharge path are formed at the housing. The pump chamber includes an inner wall having a suction region at a suction port-side and a discharge region at a discharge port-side. The suction region includes a first suction region extending towards the suction path from a pressing point, where the outer rotor is pressed when the internal gear pump is in operation, and a second suction region between the first suction region and the discharge region. A groove that enlarges a clearance between the outer rotor and the inner wall is formed in the first suction region, but the groove is not formed in the second suction region.

A rotary compressor is provided that may include a roller slidingly coupled to an eccentric portion of a rotational shaft so as to be moved along an inner circumferential surface of a cylinder by the rotational shaft, and a vane slidingly coupled to the cylinder so as to divide the compression space into a plurality of compression chambers. An oil supply groove may be formed on an outer circumferential surface of the eccentric portion or an inner circumferential surface of the roller that faces the outer circumferential surface of the eccentric portion, and a depth of the oil supply groove may decrease as a distance in a circumferential direction from the second oil supply hole increases. Accordingly, an amount of oil supplied between the eccentric portion and the roller may be increased to thereby reduce friction loss.

A rotary pump, including: a housing featuring a delivery space which includes an inlet for a fluid on a suction side of the rotary pump and an outlet for the fluid on a pressure side of the rotary pump; an inner rotor which is arranged in the delivery space; an outer rotor which is arranged in the delivery space and forms delivery cells with the inner rotor, wherein an outer circumferential wall of the outer rotor is mounted in a sliding manner on an inner circumferential wall of the delivery space, wherein the inner circumferential wall of the delivery space and/or the outer circumferential wall of the outer rotor comprises at least one pocket.