A heat source unit of a refrigerant cycle apparatus includes a compressor, a pipe, and a fixing member. The compressor includes two or three connection portions of a first connection portion connecting a suction pipe, a second connection portion connecting a discharge pipe, and a third connection portion connecting an injection pipe. The pipe includes a vertical portion. At least a part of the vertical portion extends vertically from each of the two or three connection portions. The fixing member fixes at least two of the vertical portions of two or three of the pipes of the suction pipe, the discharge pipe, and the injection pipe. Each of the connection portions of the pipes fixed by the fixing member is located on a first straight line as seen in a top view.

A scroll compressor including a center housing; a front housing fastened to the center housing and forming a suction chamber; a rear housing fastened to the center housing and forming a compression mechanism accommodation space. Fixed scroll is in the compression mechanism accommodation space. An orbiting scroll interposes between the center housing and the fixed scroll forming a compression chamber together with the fixed scroll. Fixed scroll may include a fixed scroll end plate and a fixed scroll side plate protruded from outer circumferential portion of fixed scroll end plate, fastened to the center housing, and forming orbiting space of orbiting scroll. Outer circumferential portion of the center housing may be formed with an inflow hole for communicating with the suction chamber. Distal end surface of the fixed scroll side plate is formed with a suction port for guiding the refrigerant of the inflow hole to the compression chamber.

A lower end plate cover is provided with a bulging portion. In a circumferential direction of a rotary shaft, a plurality of bolt holes includes a first bolt hole arranged between a distal end portion and a proximal end portion of the lower discharge valve, a second bolt hole arranged in a position adjacent to the first bolt hole on a side close to a lower vane groove with respect to the first bolt hole, and a third bolt hole arranged in a position adjacent to the first bolt hole on a side away from the lower vane groove with respect to the first bolt hole. When the bulging portion is divided into a first bulging portion and a second bulging portion using a first straight line, the first bulging portion is larger than the second bulging portion.

A connecting device includes a substantially cylindrical or tubular body provided, at one of its ends, with an outer perimeter projection and co-operative with a duct of channel of a cylinder cap. The device is preferably producible with steel aluminum alloy, or another metal alloy with similar structural and thermal properties mainly due to the stresses it may suffer during use. The device is configured to be able to absorb tolerance variations and to have a resilience capable of providing resistance at the time when a connection undergoes mechanical stresses of performance, especially torsion.

According to one embodiment, a compressor includes cylinders, a rotating shaft, bearings, discharge valve mechanisms, and mufflers. As to the mufflers, an outer contour of the muffler chamber is defined by each of an end face part which is a face part on one end side of the muffler in an axial direction of the rotating shaft, a brim part which is a face part on the other end side in the axial direction, and a side face part which joins the end face part and the brim part to each other in a cylindrical form in the circumferential direction of the rotating shaft, and one of the mufflers includes a concave part formed by denting each of the end face part and the side face part toward the inside of a muffler chamber.

A scroll compressor includes a casing; an orbiting scroll; a fixed scroll; and a main frame which supports the orbiting scroll. The fixed scroll may include a fixed scroll end plate and a fixed scroll wrap which protrudes from the fixed scroll end plate. The main frame may include a main frame end plate which is provided on the opposite side of the fixed scroll end plate on the basis of the orbiting scroll, and a main frame side plate which protrudes from an outer circumferential portion of the main frame end plate toward the fixed scroll. The fixed scroll end plate, the main frame end plate, and the main frame side plate may form an orbiting space of the orbiting scroll.

Disclosed is a screw compressor (100), comprising a screw compressor housing (101), a discharge cavity (113), at least one silencing channel, and at least one adjustment piston, wherein the discharge cavity (113) is defined by at least one part of the screw compressor housing (101); the at least one part of the screw compressor housing (101) defining the discharge cavity (113) forms a wall of the discharge cavity (113); at least one hole is provided in the wall of the discharge cavity (113); the at least one adjustment piston can be inserted into the at least one hole and move therein; the at least one silencing channel is formed by the at least one hole and the at least one adjustment piston, and the at least one silencing channel is in fluid communication with the discharge cavity (113); and the position of the at least one adjustment piston in the at least one hole determines the silencing length of the at least one silencing channel.

The invention relates to a vacuum pump for a motor vehicle, comprising a pump housing surface, on which a noise reduction hood delimiting a sound damping volume is mounted. The invention is characterized in that a multi-functional decoupling element is located between the pump housing surface and the noise reduction hood, said element carrying out a sealing function and a valve function in addition to a sound decoupling function.

The present invention belongs to the technological field of compressors for cooling systems and, according to a preferred embodiment of the present invention, the connecting device a substantially cylindrical or tubular body provided, at one of its ends, with an outer perimetral projection and co-operative with a duct or channel of a cylinder cap, wherein, preferably, the device will be produced with steel, aluminum alloy, or other metal alloy with similar structural and thermal properties, mainly due to the stresses it may suffer during use and to be able to absorb the tolerance variations and to have a resilience capable of providing resistance at the time the connection undergoes mechanical stresses of performance—especially torsion.

A discharge chamber, into which refrigerant compressed by a compression mechanism, is discharged, is formed in an inside of a housing. A resonator is connected to an intermediate portion of a communication passage, which communicates between the discharge chamber and a discharge port of the housing. The resonator includes a resonance chamber and an inlet passage. The inlet passage has one end portion, which is connected to the intermediate portion of the communication passage, and another end portion, which is connected to the resonance chamber.