A scroll compressor including a housing, a motor provided in the housing, a rotary shaft configured to be rotated by the motor, an orbiting scroll configured to orbit in conjunction with the rotary shaft, a fixed scroll configured to define a compression chamber together with the orbiting scroll, and a discharge valve disposed on one surface of the fixed scroll and configured to open or close one or more discharge openings of the fixed scroll through which a refrigerant compressed in the compression chamber is discharged, in which the discharge valve includes: a discharge reed plate disposed on one surface of the fixed scroll, and a gasket retainer disposed between one surface of the fixed scroll and the housing and configured to surround the discharge reed plate.

A dry vacuum pump includes an elastic outer seal and at least one elastic inner seal respectively including a first and a second end annular parts parallel to one another and inserted between a respective end piece and the half-shells, and two side rails connecting the end annular parts and which are at right angles thereto, the side rails being inserted between the half-shells, the at least one inner seal being arranged inside the outer seal so that the at least one inner seal and the outer seal form at least two successive sealing barriers for the gases.

A scroll compressor is provided. The scroll compressor includes a fixed scroll, an orbiting scroll configured to orbit with respect to the fixed scroll and including an orbiting end plate, and a main frame to which the orbiting scroll is coupled to orbit. The scroll compressor includes a compression chamber in which a refrigerant is compressed by the fixed scroll and the orbiting scroll, and a first back pressure chamber and a second back pressure chamber provided to communicate with the compression chamber. The first back pressure chamber and the compression chamber communicate with each other through a first flow path. The second back pressure chamber and the compression chamber communicate with each other through a second flow path. A different intermediate back pressure is formed in the first back pressure chamber and the second back pressure chamber.

A rotary internal combustion engine has: a rotor; a housing circumscribing a rotor cavity, the rotor received within the rotor cavity, the housing having a peripheral wall and a side housing assembly secured to the peripheral wall, the side housing assembly having plates located at spaced apart ends of the peripheral wall, the plates defining seal running surfaces in sealing engagement with opposed end faces of the rotor, the plates made of silicon carbide.

Rotary positive displacement machines based on trochoidal geometry, that comprise a helical rotor that undergoes planetary motion within a helical stator are described. The rotor can have a hypotrochoidal cross-section, with the corresponding stator cavity profile being the outer envelope of the rotor as it undergoes planetary motion, or the stator cavity can have an epitrochoidal cross-section with the corresponding rotor profile being the inner envelope of the trochoid as it undergoes planetary motion. In some embodiments, the geometry is offset in a manner that provides structural and/or operational advantages in the rotary machine.

A compressor includes a shell, a first scroll member, a second scroll member and a sealing assembly. The shell defines a first pressure region and a second pressure region. The first scroll member is disposed within the shell and includes a first end plate and a first scroll wrap. The second scroll member includes a second end plate and a second scroll wrap. The second scroll wrap meshingly engages the first scroll wrap to define a compression chamber therebetween. The seal assembly fluidly separates the first and second pressure regions from each other. The seal assembly includes a first plate, a second plate, a sealing member. The sealing member is sealingly engaged with the first plate and the second plate.

A roots blower includes driving and driven rotors that rotate while intermeshing with each other, driving and driven shafts fixed at the shaft centers of the driving and driven rotors, respectively, a driving gear attached to the end of the driving shaft, a driven gear that is attached to the end of the driven shaft and intermeshes with the driving gear, a rotor chamber that houses the driving and driven rotors, a gear chamber that houses the driving and driven gears, and driving and driven bearings that rotatably support the driving and driven shafts, respectively. The driving and driven gears are lubricated by a grease.

A compressor may include a shell, first and second scroll members, a floating seal, a muffler plate, and a wear ring. The shell defines a discharge chamber and a suction chamber. The floating seal may sealingly engage the second scroll member. The muffler plate defines the discharge chamber and the suction chamber. The wear ring may sealingly engage the muffler plate and the floating seal such that the wear ring, the muffler plate, and the floating seal fluidly isolate the discharge chamber from the suction chamber. The muffler plate may include an axially facing surface that contacts the wear ring. The axially facing surface may include an annular recess. The wear ring may at least partially cover the annular recess. The annular recess may provide clearance between the muffler plate and the wear ring to allow the wear ring to deflect relative to the muffler plate during compressor operation.

An electric compressor includes a cylindrical motor housing, an inverter case, and a conductive member. The inverter case is joined to an end portion of the motor housing. The inverter case includes a cylindrical case peripheral wall surrounding the end portion. The end portion has an end face that extends in a radial direction of the motor housing and a peripheral surface that extends in an axial direction of the motor housing and is connected to the end face. A ring-shaped sealing member is disposed between the peripheral surface and the case peripheral wall. An accommodation groove for accommodating the sealing member is recessed in the peripheral surface. The sealing member is held by the peripheral surface and the case peripheral wall in a radial direction of the sealing member to seal a space in which the conductive member is disposed.

A compressor may include a compression mechanism and a shell assembly. The shell assembly may include first and second snap rings, a body, and first and second caps cooperating with the body to enclose the compression mechanism therein. The body may include first and second ends and an inner surface extending between both ends. The first cap may be received within the first end and may include a first side wall having a first groove. The second cap may be received within the second end and may include a second side wall having a second groove. The first snap ring may be disposed within the first groove and may engage the first end to restrict removal of the first cap from the body. The second snap ring may be disposed within the second groove and may engage the second end to restrict removal of the second cap from the body.