Scroll-type fluid displacement apparatus with rotation prevention/thrust

Abstract

A scroll-type of fluid displacement apparatus is disclosed. The apparatus includes a housing having a fluid inlet and a fluid outlet port. A fixed scroll member is fixedly disposed with respect to the housing and has an end surface from which a first wrap extends. An orbiting scroll member is movably disposed within the housing and has an end plate from which a second wrap extends. The first and second wraps interfit at an angular offset to make a plurality of line contacts which define at least one pair of sealed off fluid pockets. A drive mechanism is connected to the orbiting scroll member to transmit orbital motion thereto. A rotation preventing means prevents rotation of orbiting scroll member during orbital motion of the orbiting scroll member and is comprised of fixed ring and a sliding ring. The sliding ring is slidably connected to the fixed ring and also to the second end plate by keys and keyways. A plurality of pockets is formed through the sliding ring and bearing elements are retained within the pockets for transmitting axial thrust load from the orbiting scroll member to the fixed ring.