A scroll compressor includes a hermetic container, a fixed scroll, a swing scroll, a frame, an electric motor, and a shaft. A first groove and a second groove are provided outside a fixed wrap in a radial direction at an end plate surface of the fixed scroll. An oil supply hole for guiding lubricant oil from a through-hole opens at an end plate surface of the swing scroll. A single opening of the oil supply hole alternately communicates with the first groove and the second groove along with swing of the swing scroll.

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 scroll compressor with oil return unit, having a fixed spiral and an orbiting spiral, which compresses gas from a suction-pressure chamber into a high-pressure chamber. A counter-pressure chamber is connected to the orbiting spiral and the orbiting spiral presses onto the fixed spiral. The oil return unit has a counter-pressure spiral nozzle having a high-pressure channel connected to an end face for oil supply. A suction-pressure spiral nozzle with a suction-pressure channel connected to the end face discharges oil into the suction-pressure chamber. A counter-pressure channel is arranged between the counter-pressure spiral nozzle and the suction-pressure spiral nozzle for discharging oil into the counter-pressure chamber.

A vacuum pumping system includes a plurality of positive displacement vacuum pumps, and more particularly a plurality of positive displacement vacuum pumps working in parallel. The vacuum pumping system includes a management unit that carries out a synchronized control of all the positive displacement vacuum pumps of the vacuum pumping system and thus allows to check possible risk of contamination of the vacuum pumping system and carry out, if needed, the necessary corrective actions without requiring any modification to the construction of the vacuum pumping system.

An oil-injected multistage compressor device that comprises at least one low-pressure stage compressor element (2) with an inlet (4a) and an outlet (5a) and a high-pressure stage compressor element (3) with an inlet (4b) and an outlet (5b), whereby the outlet (5a) of the low-pressure stage compressor element (2) is connected to the inlet (4b) of the high-pressure stage compressor element (3) via a conduit (6), characterized in that an intercooler (9) is provided between the low-pressure stage compressor element (2) and the high-pressure stage compressor element (3) in the aforementioned conduit (6) and that the compressor device (1) is also equipped with a restriction (10) for limiting the amount of oil injected in the low-pressure stage compressor element (2).

A screw compressor for a utility vehicle includes at least one housing, at least one housing cover and at least one rotor housing. At least one seal is provided, wherein, when assembled, there is an oil sump in the housing, and the seal is arranged between the housing cover and the rotor housing and projects out of the oil sump with respect to the assembled state. The seal is formed as a sealing plate and has multiple passage openings.

Provided is a liquid supply mechanism including: a plurality of liquid supply sections each including a plurality of branch paths whose central axes intersect with each other, and a supply path having a side surface to which the plurality of branch paths of the plurality of liquid supply sections are directly connected, respectively, and supplying liquid, which is supplied from an upstream, to the branch paths.

A scroll compressor includes fixed and movable scrolls forming a compression chamber, a back pressure chamber, and outer and inner oil supply mechanisms that supply oil to outer and inner chambers of the compression chamber. The inner oil supply mechanism includes an oil supply portion formed in a sliding surface of the fixed scroll to communicate with a suction region of the compression chamber and a communication port passing through the sliding surface of the movable scroll to communicate with the back pressure chamber. The communication port communicates with the oil supply portion within a predetermined period in which a center position of a suction-side end of the wrap of the movable scroll in a thickness direction is located radially outward of a center position of a space between adjacent turns of a wrap of the fixed scroll, during one rotation of the movable scroll.

A scroll compressor includes a motor portion fixed in an inner space of a casing, a compression portion fixed to the inner space of the casing at one side of the motor portion in an axial direction, a rotation shaft to transmit a driving force from the motor portion to the compression portion, and a flow path guide provided in a discharge space between the motor portion and the compression portion and provided with a guide outlet communicating with the discharge space and opened in a direction toward the rotation shaft. Therefore, most of refrigerant discharged to the discharge space through the flow path guide is moved toward an air gap to enhance an oil separation effect, and thus a normal operation point of the air conditioner can be accelerated.

A compressor includes a casing configured to accommodate refrigerant and oil, a discharger disposed at a side of the casing and configured to discharge the refrigerant, a driver including a stator and a rotor, a rotation shaft that is coupled to the rotor and that extends in a direction away from the discharger, a compressing assembly that is coupled to the rotation shaft, that is configured to be lubricated with the oil, and that is configured to compress the refrigerant and discharge the compressed refrigerant in the direction away from the discharger, a muffler coupled to the compressing assembly and configured to guide the refrigerant to the discharger, and a bypassing portion disposed outside the casing and configured to transfer the refrigerant or the oil from the muffler to the discharger.