A compressor includes a shell assembly, a muffler plate and a compression mechanism. The shell assembly has a suction chamber and a discharge chamber. The muffler plate is disposed within the shell assembly and separates the suction chamber from the discharge chamber. The muffler plate includes a hub having a circumferentially extending inner portion and a circumferentially extending intermediate portion. The circumferentially extending inner portion defines a discharge passage extending therethrough. The circumferentially extending intermediate portion has a slot formed in a surface thereof. The slot extends at least partially around the circumferentially extending intermediate portion. The compression mechanism is disposed within the suction chamber and provides working fluid to the discharge chamber via the discharge passage of muffler plate.

A seal for use in a vacuum pump comprises a seal element positioned between inner and outer seal carriers located at the inner and outer surfaces of the seal element. Each of the seal element and carriers is substantially toroidal in shape. The outer carrier comprises retention means to hold the seal element in position. The inner carrier comprises at least one recess located in a surface adjacent to the seal element, and the seal element comprises at least one protrusion on an inner surface, which extends into the at least one recess of the inner carrier. A seal system comprises the described seal and first and second flanges. Methods for enhancing the chemical resistance of a seal system for use in a vacuum pump, and the use of the seal or seal system to connect pipework, are also provided.

A magnetic coupling assembly includes a first balancing magnet positioned and surrounding drive magnets and, across a gap, a second balancing magnet and surrounding driven magnets. The drive magnets when rotated drive the driven magnets to rotate. The balancing magnets generate a repulsive force, which counterbalances an attractive force generated by the drive magnets and driven magnets. The assembly may be utilized in a pump for contactless coupling of a motor shaft to a pump shaft. The driven side of the assembly may be hermetically sealed, such as with a liquid crystal polymer boundary interposed in the gap.

A rotary vacuum pump includes a housing defining a pump chamber therein and a rotor extending through a first axial end panel into the pump chamber and carrying at least one vane for rotary movement of the vane within the pump chamber. The rotor comprises an annular axial end face configured to seal against a corresponding contact surface of a second axial end panel. An annular groove for reducing noise generation of the rotary vacuum pump during operation is formed at the annular axial end face of the rotor and/or the contact surface of the second axial end panel.

Disclosed is a scroll compressor including stationary and movable scroll members engaged with each other. The stationary scroll member defines first and second air inlets and first and second air outlets. A first compression path is formed between the first air inlet outlet, and a second compression path is formed between the second air inlet outlet. The scroll compressor further includes a bypass passage for selectively communicating at least one of the first and second compression paths with a suction pressure area of the compressor. First and second back pressure cavities are formed on a side of the stationary scroll member facing away from the movable scroll member. The first back pressure cavity is in communication with the first compression path by means of a first back pressure passage. The second back pressure cavity is in communication with the second compression path by means of a second back pressure passage.

A back pressure chamber forming portion forms a back pressure chamber configured to accumulate a high pressure refrigerant discharged from a working chamber and thereby generate a refrigerant pressure, which urges a movable scroll against a stationary scroll. A balancer is placed at an inside of the back pressure chamber and is configured to be rotated by a rotatable shaft. The back pressure chamber forming portion has a discharge hole that communicates between a radially outer side of the back pressure chamber, which is located radially outward in a radial direction of an axis of the rotatable shaft, and a suction chamber to discharge a liquid phase refrigerant from the back pressure chamber into the suction chamber when the liquid phase refrigerant flows from the working chamber into the back pressure chamber.

A scroll compressor includes a housing, a rotary shaft, a movable scroll, an eccentric shaft, an opposed wall, a looped elastic plate, a looped support portion, an annular protrusion, a back pressure chamber, and a back pressure supplying groove. The distance in the radial direction of the rotary shaft from the rotation axis of the rotary shaft to then outer end of the back pressure supplying groove in the radial direction of the rotary shaft is shorter than or equal to the distance obtained by subtracting the distance in the radial direction of the rotary shaft between the rotation axis of the rotary shaft and the axis of the eccentric shaft from the distance in the radial direction of the rotary shaft from the axis of the eccentric shaft to the part of the protrusion that contacts the elastic plate.

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 first sealing member and a second sealing member. The first sealing member is sealingly engaged with the first plate and the second plate. The second sealing member is sealingly engaged with the first sealing member and the first plate.

An electric compressor includes a housing including a compression part housing, a shaft support housing, and a motor housing fastened by a plurality of fastening members. A peripheral wall has a plurality of thick-walled portions that protrudes inwardly in a radial direction and through which their associated fastening members are inserted. The fixed scroll base plate has a plurality of protruded portions each protruding outwardly in the radial direction and disposed between the thick-walled portions in a circumferential direction. The fixed scroll base plate has a plurality of pillar portions each extending from the protruded portions toward the shaft support housing in the axial direction and spaced from each other in the circumferential direction. The elastic plate is held at a plurality of spots by the plurality of pillar portions and the shaft support housing.

A compressor may include first and second scrolls, and an axial biasing chamber. Spiral wraps of the scrolls mesh with each other and form compression pockets including a suction-pressure compression pocket, a discharge-pressure compression pocket, and intermediate-pressure compression pockets. The axial biasing chamber may be disposed axially between the second end plate and a component. Working fluid disposed within the axial biasing chamber may axially bias the second scroll toward the first scroll. The second end plate includes outer and inner ports. The outer port is disposed radially outward relative to the inner port. The outer port may be open to a first one of the intermediate-pressure compression pockets and in selective fluid communication with the axial biasing chamber. The inner port may be open to a second one of the intermediate-pressure compression pockets and in selective fluid communication with the axial biasing chamber.