A compression unit of a rotary compressor includes a cylinder, an upper end plate that closes the upper side of the cylinder, a lower end plate that closes the lower side of the cylinder, and a piston that is fitted to a rotating shaft, revolves along an inner peripheral surface of the cylinder, and forms a cylinder chamber in the cylinder. At least one of an end face of the piston in the axial direction of the rotating shaft, a sliding surface of the upper end plate that slides with the end face of the piston, and a sliding surface of the lower end plate that slides with the end face of the piston, has formed therein an oil-film retention region having an array of a plurality of recessed portions that retain lubricating oil.

Disclosed are an outer ring for an oil pump having an increased number and size of open pores in a surface of a molded article and a method for manufacturing the outer ring.

The disclosure relates to a pump assembly for a vehicle having an internal combustion engine with or without transmission or electric motor with transmission or for an oil supply having a double-pipe pump, wherein the two pipes are separated from each other and a second pipe can be connected to a first pipe, wherein the pump has at least one input drive point for an electric machine and also for a drive motor, including, for example, via a gearbox.

A first communication groove (38) extending from a start point of a discharge port (36) in a direction opposite to rotation direction of vanes (22) is formed. A first end portion (38E) of this groove is connected to the start point of the discharge port (36). When a front-side vane in a rotation direction of a driving shaft (11) is positioned at the start point of the discharge port (36), a second end portion (38S) of the groove is positioned at a rear side in the rotation direction with respect to a rear-side vane coming immediately after the front-side vane, and communicates with a suction port (35). A part of working fluid in a front-side pump chamber (27-1) can therefore be introduced into a rear-side pump chamber (27-2) that communicates with the suction port (35), thereby lessening excessive pressure increase of the front-side pump chamber (27-1) and suppressing pulsation phenomenon.

A first communication groove (38) extending from a start point of a discharge port (36) in a direction opposite to rotation direction of vanes (22) is formed. A first end portion (38E) of this groove is connected to the start point of the discharge port (36). When a front-side vane in a rotation direction of a driving shaft (11) is positioned at the start point of the discharge port (36), a second end portion (38S) of the groove is positioned at a rear side in the rotation direction with respect to a rear-side vane coming immediately after the front-side vane, and communicates with a suction port (35). A part of working fluid in a front-side pump chamber (27-1) can therefore be introduced into a rear-side pump chamber (27-2) that communicates with the suction port (35), thereby lessening excessive pressure increase of the front-side pump chamber (27-1) and suppressing pulsation phenomenon.

A vane cell pump, includes a rotatable rotor having vanes which can be moved back and forth; an end plate with a pressure passage for discharging pressure fluid and a supply passage for supplying a sub-vane region with pressure fluid; a flow channelling device on an end face of the end plate facing axially away from the rotor; a first outlet region for discharging a first partial flow of the pressure fluid; a second outlet region for discharging a second partial flow of the pressure fluid; a first flow path along which the first partial flow flows through the first outlet region; a second flow path connecting the pressure passage to the supply passage, diverges from the first flow path and is delineated by the flow channelling device; and a third flow path connecting the supply passage to the second outlet region and delineated by the flow channelling device.

A variable displacement vane pump has a control slide displaceable within its housing and a first control chamber and a second control chamber for receiving pressurized lubricant. A thermally adjustable control valve is provided in the housing for adjusting pump displacement based on a temperature of the lubricant. In addition to fluid communication channels in the control chambers, at least one vent port is provided in the second chamber. The control valve is configured to control pressure and fluid communication between the chambers along with the control slide. The control valve can help reduce pump displacement at lower temperatures and low engine speeds. At lower temperatures, the second control chamber can be pressurized by the first control chamber. At higher temperatures, the second control chamber can be vented through the control valve and/or the vent port, despite the position of the control slide.

A rotary cylinder piston compressor pump is provided, including a rotating shaft (2), a piston (3) and a cylinder (4). A rotating shaft hole (21) is provided in the rotating shaft (2). An oil guiding channel, provided in the cylinder (4), communicating with the rotating shaft hole (21). A recess (45) is formed in the inner end face of the cylinder (4). An oil path (61) sealed relative to a compression cavity (49) of the cylinder (4) is formed between the recess (45) and the piston (3). The oil path (61) between the recess (45) and the piston (3) is communicated with an oil path (62) between the piston (3) and the rotating shaft (2) and is communicated with the oil guiding channel by means of an oil returning channel. Also provided is a compressor including the compressor pump.

A rotary compressor may include a cylinder having an inner peripheral surface defined in an annular shape to define a compression space, and a suction port that extends in a lateral direction to communicate with the compression space and through which refrigerant is suctioned into the compression space; a roller rotatably provided in the compression space of the cylinder, and having a plurality of vane slots that provides a back pressure at one side thereinside provided at a predetermined interval along an outer peripheral surface of the roller; a plurality of vanes slidably inserted into the plurality of vane slots, respectively, to rotate together with the roller, front end surfaces of which come into contact with the inner peripheral surface of the cylinder due to the back pressure to partition the compression space into a plurality of compression chambers; and a main bearing and a sub bearing provided at ends of the cylinder and in contact with surfaces of the plurality of vanes, respectively, and spaced apart from each other to define surfaces of the compression space, respectively. At least one surface of the vane in contact with the main bearing and the sub bearing may be a curved surface having a predetermined curvature.

A variable displacement pump can include a rotor having a plurality of vanes, a cam ring surrounding the rotor and vanes, the vanes configured to extend from the rotor and contact an inner cam surface of the cam ring, and a retainer configured to contact the cam ring and to move the cam ring relative to the rotor to modify a pumping action. The pump can also include a direct actuation mechanism configured to control a position of the retainer to control a position of the cam ring and the pumping action.