In a screw compressor (20), a male rotor suction end bearing (96) and discharge end bearing (90 1, 90 2, 90 3) mount the male rotor suction end shaft portion (39) and discharge end shaft portion (40). A female rotor suction end bearing (98) and discharge end bearing (92 1, 92 2) mount the female rotor suction end shaft portion (41) and discharge end shaft portion (42). At least one valve (182; 282; 382 1,382 2,382 3; 82; 582-1,582-2; 682-1,682-2; 782-1,782-2) is along a lubricant flowpath and has an energized condition and a de-energized condition. At least one restriction (184; 84-1,84-2; 84-1, 84-2,84-3; 484 1,484-2,84-3; 84 1,84 2,584; 84-1,84-2,684; 84-1,84-2,784) is along the lubricant flowpath. The at least one valve and the at least one restriction are positioned to create a lubricant pressure difference biasing the rotors away from a discharge end of the case.

The present invention provides an improved vacuum pump assembly for a motor vehicle comprising of a housing, a rotor, modified vane, a sealing ring, a cover, wherein, the modified vane containing a vane slider is having at least one oil vent or relief hole or slot, for the reduction of the exit port oil peak pressure, by channelizing oil supplies to the vane top and bottom face, thereby improving the seal-ability between the moving and stationary part of the pump; and the modified vane further having an oil vent control at the exit port, for maintaining oil pressure and reducing the exit port hydraulic pressure, leading to reduction in the opposite end vane slider tip load causing low friction between the pump housing, the vane and vane slider, and further channelizing the excess amount of oil to the vane top face which creates additional sealing between the vane and the housing, reducing the air leakage between the low pressure chamber and high pressure chamber inside the pump.

A scroll compressor includes fixed and movable scrolls having a fixed and movable side plates and fixed and movable side laps to form first and second compression chambers. The fixed-side plate includes a discharge port and a relief hole extending from the front face through to the back face. The relief hole communicates for a predetermined amount of time with each of the first and second compression chambers and is shared by the first and second compression chambers. The front face of the movable-side plate includes a recessed part allowing the second compression chamber and the discharge port to communicate. The second compression chamber, during a latter stage of compression, and the discharge port communicating via a gap formed between a tip of the fixed-side lap and the recessed part before communicating via a side face gap formed between the fixed-side lap and the movable-side lap.

A compressor includes a drive shaft having a main shaft and an eccentric portion, and a compression mechanism having a fitted tubular portion into which a fitted shaft portion of the drive shaft is slidably fitted. The fitted shaft portion has first and second sliding surfaces formed as portions of an outer peripheral surface in the circumferential direction. The second sliding surface has a smaller axial width than the first sliding surface. A gap is adjacent to the second sliding surface into which a lubricating oil flows. An oil retainer is configured as a boundary portion between the first sliding surface and the gap to keep the lubricating oil in the gap from flowing out toward an end surface of the fitted shaft portion. The boundary portion has a central portion that protrudes further toward the first sliding surface than an end of the boundary portion in a lubricating oil flow-out direction.

A unique compressor system may include a compressor having a compressor housing. The compressor housing may include an oil drainage passage formed therein. The passage may be configured to drain oil from bearings and other oil-lubricated components of the compressor. The compressor may be coupled to a gearbox or an oil tank. The gearbox or oil tank may include a passage that is in fluid communication with the oil drainage passage. The gearbox or oil tank passage may be operative to receive the drained oil and to direct the drained oil to an oil tank.

A squeeze film damper assembly for a compressor includes a damper sleeve configured to be disposed about a rotor shaft of the compressor. The damper sleeve includes a pressure dam pocket formed in an inner circumference of the damper sleeve. The pressure dam pocket is configured to receive a flow of lubricant and to pressurize the flow of lubricant via rotation of the rotor shaft. The damper sleeve includes an outlet passage extending from the pressure dam pocket to an outer circumference of the damper sleeve. The squeeze film damper assembly also includes a bearing housing disposed about the damper sleeve to form a damper gap extending between the outer circumference of the damper sleeve and the bearing housing. The damper gap is fluidly coupled to the outlet passage and is configured to receive the flow of lubricant from the pressure dam pocket.

A second space communicated with a first space through communicating paths is provided on an outer circumferential side of first and second scroll bodies. Scroll end portions of the first and second scroll bodies form an inlet port configured to suck gas refrigerant into a compression chamber from the second space. Open ends of the communicating paths on a side of the second space are located at an angle larger than 0° and less than or equal to 180°, around a central axis of a rotating shaft portion, from the inlet ports in a scroll involute direction of the first scroll body and the second scroll body, respectively. Injection ports in a part of an outer circumference of the second space between the open ends and the inlet ports in a circumferential direction are configured to eject liquid refrigerant in a direction toward the inlet ports, respectively.

A compressor includes a compression mechanism that compresses refrigerant; a main shaft that transmits a rotational driving force to the compression mechanism; a balance weight provided below the compression mechanism and integrated with the main shaft, the balance weight having a cylindrical outer peripheral surface centered at the main shaft; and an oil sump portion provided below the balance weight and stores lubricating oil to be supplied to the compression mechanism. The balance weight has an annular oil-receiving recessed portion in an upper surface, the oil-receiving recessed portion being centered at the main shaft and integrated with the balance weight. The balance weight has a hollow portion in a lower surface, the hollow portion extending in part of the lower surface in a peripheral direction around the main shaft and being integrated with the balance weight. The oil-receiving recessed portion communicates with at least part of the hollow portion.

A scroll compressor includes a fixed scroll and an orbiting scroll and causes the orbiting scroll to perform an orbiting motion to form a suction chamber and a compression chamber. The scroll compressor includes a first space in a back surface center of the orbiting scroll, lubricant in a bottom of a sealed container, a second space provided further on an outer circumference side than the first space on a back surface of the orbiting scroll, a first oil leak path for causing a part of oil in the first space to leak to the second space, an oil return passage for returning most of the oil in the first space to the bottom in the sealed container, a second oil leak path for causing a part of the oil in the second space to leak to the suction chamber, and a third oil leak path.

A scroll compressor according to the present disclosure includes a fixed scroll, an orbiting scroll forming first and compression chambers with the fixed scroll, first and second compression chamber oil supply holes formed through the orbiting scroll to communicate with the first compression chamber and the second compression chamber, respectively, wherein when a section in which the first compression chamber oil supply hole is opened toward the first compression chamber is a first oil supply section and a section in which the second compression chamber oil supply hole is opened toward the second compression chamber, a non-overlap section between the first oil supply section and the second oil supply section may be longer than an overlap section between the first oil supply section and the second oil supply section, so as to prevent communication between the first and second compression chambers, thereby suppressing leakage between the compression chambers.