Abstract: A scroll compressor has a stationary scroll member and an orbiting scroll member which moves around the stationary scroll member to consecutively compress working fluid. A piston is provided to urge the orbiting scroll member to come close to the stationary scroll member. The piston is driven to urge the orbiting scroll member by compressed working fluid which is guided to enter an annular chamber communicating with compressed working fluid or working fluid being compressed. By this arrangement, the mechanical efficiency of the scroll compressor will be enhanced, and mixing of working fluid and lubricant is able to be reduced. Furthermore, the wobbling of the orbiting scroll member will also be diminished.

Abstract: A scroll type compressor comprising a housing inside which a stationary scroll member and a frame are fixed to define a space therebetween large enough to receive therein an orbiting scroll member which inter-engages with the stationary scroll member to define therebetween a hermetical compression pocket into which the fluid to be compressed fills. An Oldham-coupling ring restricts the orbiting scroll member to orbit around the center of the stationary scroll wrap only. A back pressure chamber is in pressure connection with the compressed fluid through a lubricant for the compressor and also in fluid connection with an inlet of the fluid to be compressed through a capillary-like passage.