In a rotary compressor, a lower end plate cover is formed in a flat plate shape, a lower discharge chamber concave portion is formed in a lower end plate to overlap a lower discharge hole side of a lower discharge valve accommodation concave portion, and the lower discharge chamber concave portion is formed in a fan-like range between a diametrical line passing through a center of a sub-bearing unit and a midpoint of a line segment connecting a center of the lower discharge hole and a center of a lower rivet to each other and a diametrical line opened by a pitch angle 90° in a direction of the lower discharge hole about the center of the sub-bearing unit. At least a portion of a refrigerant path hole overlaps the lower discharge chamber concave portion and is disposed at a position communicating with the lower discharge chamber concave portion.

A pump includes a first housing part defining a first portion of a bore extending within the first housing part and shaped to receive a rotor; and a second housing part defining a second portion of the bore extending within the second housing part and shaped to receive the rotor. The first housing part has a first face abutable against an opposing second face of the second housing part to position the first portion of the bore with the second portion of the bore to receive the rotor. The first portion of the bore has a first circular cross-section portion centered along the first face and the second portion of the bore having a second circular cross-section portion centered, within the second housing part, at a distance from the second face.

A multistage Roots pump comprise a plurality of pump chambers in a pump housing. They constitute respective pump stages, wherein each pump stage comprises two two-toothed rotary pistons. The pump stages are separated from each other by partition walls. In the partition walls essentially radially extending connecting ducts are arranged. The connecting ducts are connected with an inflow chamber whose inflow opening has a larger cross-section than the connecting ducts.

A motor-driven compressor includes an electric motor driven by a motor driver, which includes a switching element that converts DC voltage from a battery to AC voltage. A temperature detector detects the temperature of the switching element. A voltage detector detects DC voltage applied to the switching element from the battery. A control unit suspends the switching operation of the switching element when the detected temperature rises to a temperature threshold. The control unit reduces counter electromotive force generated by the electric motor. The controller changes the temperature threshold such that the temperature threshold gradually increases from when the detected DC voltage is the highest voltage in the applicable voltage range of the battery to when the detected DC voltage is the lowest voltage in the applicable voltage range.

A compressor may include a shell, first and second scroll members, a partition plate and a bypass valve member. The shell defines a discharge-pressure region and a suction-pressure region. The first scroll member is disposed within the shell and may include a first end plate having a discharge passage, and first and second bypass passages extending through the first end plate. The partition plate is disposed within the shell and separates the discharge-pressure region from the suction-pressure region and includes an opening in communication with the discharge-pressure region. The bypass valve member is movable between a first position restricting fluid flow through at least one of the first and second bypass passages and the opening and a second position in allowing fluid flow through the at least one of the first and second bypass passages and the opening.

A fluid machine includes a main body, two first screw rotors, two second screw rotors, a driving module, a first slide member and a second slide member. The two first screw rotors are meshingly engaged with each other. The two second screw rotors are meshingly engaged with each other. Two first screw rotors are arranged in the first chamber of the main body. Two second screw rotors are arranged in the second chamber of the main body. The driving module is arranged in the drive chamber of the main body. The first slide member can move relative to the two first screw rotors. The second slide member can move relative to the two second screw rotors. A fluid entering the main body exits after being compressed or expanded by the two first screw rotors and the two second screw rotors.

A compressor including a gear system configured to be driven by a drive unit, a plurality of compression stages coupled to the gear system, wherein the plurality of compression stages includes at least one centrifugal compression stage and at least one positive displacement compression stage, is provided. Furthermore, an associated method is also provided.

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 fitted. The fitted shaft portion and the fitted tubular portion slide relative to each other with an oil film interposed between. The fitted tubular portion has first and second sliding surfaces formed as portions of an inner peripheral surface of the fitted tubular portion in the circumferential direction. The second sliding surface has a smaller axial width than the first sliding surface. A sliding portion between the fitted shaft portion and the fitted tubular portion has a gap adjacent to the second sliding surface into which a lubricating oil flows, and an oil retainer to keep the lubricating oil in the gap from flowing out toward an end surface of the fitted tubular portion.

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.

The disclosure provides an oil tubing installation assembly and a scroll compressor adopting the same. The oil tubing installation assembly is adapted to be installed into a shell in a vertical direction and includes: a housing on which a vertical oil tubing installation surface and an oil hole located in the oil tubing installation surface are provided; a clip adapted to be installed on the oil tubing installation surface and into the shell along with the housing; and an oil tubing assembly adapted to be installed into the clip in a vertical direction after the housing and the clip have been installed into the shell. The oil tubing assembly includes an oil tubing body and a cuboid-shaped installation block. A through hole is provided in the installation block and the through hole is configured to have a first orifice on the front surface of the installation block and a second orifice on the rear surface of the installation block. The upper end of the oil tubing body is connected to the first orifice. The second orifice is aligned with and fitted to the oil hole after the installation block is installed in place in the clip. In this way, the long oil tubing can be easily installed manually in place even after the housing has been pressed into the shell.