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 method for controlling the liquid injection of a compressor device, where the compressor device includes at least one compressor element, the compressor element includes a housing that includes a compression space in which at least one rotor is rotatably affixed by bearings, and liquid is injected into the compressor element. The method includes providing two independent separated liquid supplies to the compressor element, where one liquid supply is injected into the compression space and the other liquid supply is injected at the location of the bearings.

A scroll type gas machine that can suppress wear of tip seals is provided. The scroll type compressor includes: a fixed scroll 11 having a helical wrap 16; an orbiting scroll 12 having a helical wrap 21; a drive shaft 13 that causes the orbiting scroll 12 to orbit relative to the fixed scroll 11; and a helical tip seal 29A inserted into a seal groove 28A of the wrap 21. The tip seal 29A has: a groove 36A that has an opening at a central portion of a sliding surface 30 in the seal width direction; and a communication groove 37A that establishes communication between the inside of the groove 36A and a working chamber S.sub.H on the inner side in the wrap width direction. The groove 36A is provided in a range where the differential pressure (P.sub.H−P.sub.L) is equal to or higher than 0.1 Mpa between the working chamber S.sub.H on the inner side in the wrap width direction and a working chamber S.sub.L on the outer side in the wrap width direction. The communication groove 37A is shorter than the groove 36A in the seal extension direction.

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.

A scroll pump includes first and second scroll members connected together by a plurality of idler assemblies configured to allow the second scroll member to move in an orbital path with respect to the first scroll member. A rotary bearing is connected to an end plate of the orbiting scroll member. A motor and motor coupler are coupled to the rotary bearing to move the bearing in an orbital path corresponding to the orbital path followed by the second scroll member. The rotary bearing may roll freely within the coupler.

A scroll pump includes a first scroll member having a first involute, a second scroll member scroll member having a second involute, and a camshaft rotatably connected to the first scroll member and to the second scroll member. A link is pivotably connected to the first scroll member and the second scroll member. The first and second scroll members cooperate to define a working volume wherein a working fluid is pressurized during operation of the scroll pump. The second scroll member is configured to equalize pressure across first and second opposed surfaces of an end plate thereof. The second scroll member includes a piston and cavity configured to bias the second scroll member toward the first scroll member in response to pressure across the first and second opposed surfaces of the end plate of the second scroll member.

The present invention provides a method of replacing a failed pump seal of a pump having a pump housing and a rotating pump shaft. As part of the method, there is provided a specially configured rescue seal. The rescue seal is placed on the pump shaft above the failed seal so that the pump shaft extends through both the failed seal and the rescue seal. In order to affix the rescue seal to the pump shaft and above the failed seal, a plurality of studs are first attached to the pump housing after removing some of the bolts that fasten the failed seal to the pump housing. The failed seal is then secured to the studs with nuts. Nuts are then placed on the studs to secure the rescue seal to the studs above the failed seal.

An air injection enthalpy-increasing scroll compressor is provided. The compressor has a main frame, a movable scroll plate and a stationary scroll plate. The movable scroll plate has a movable plate end plate and a movable scroll wrap arranged on a side end face of the movable plate end plate. A back pressure chamber is defined between the movable plate end plate and the main frame. The stationary scroll plate has a fixed scroll end plate and a stationary scroll wrap arranged on a side end face of the fixed scroll end plate. The stationary scroll wrap and the movable scroll wrap are engaged with each other to form a crescent-shaped compression cavity. The movable scroll plate and the stationary scroll plate are provided with medium pressure passages that, during the rotation of the movable scroll plate, communicate the compression cavity with the back pressure chamber.

A scroll compressor includes a main body, a cover to divide the main body into a low pressure section and a high pressure section, a fixed scroll including a first discharge port, an orbiting scroll to rotate with respect to the fixed scroll and to form a compression chamber together with the fixed scroll, a discharge guide disposed between the fixed scroll and the cover and including a second discharge port connected to the first discharge port, and a back pressure actuator configured to form a back pressure chamber together with the discharge guide and to move in a direction toward the cover with respect to the discharge guide to selectively connect the second discharge port with the high pressure section. The fixed scroll includes a bypass flow path connecting the compression chamber and the second discharge port and a bypass valve to open or close the bypass flow path.