Patent ID: 8246331

Claim:
A fluid scroll machine, comprising: an orbiting scroll; a non-orbiting member including a slide groove and a non-orbiting scroll; and a rotating shaft, wherein the rotating shaft is provided with an eccentric portion which is eccentric relative to the axis of rotation of the rotating shaft, and the orbiting scroll which engages the eccentric portion moves orbitally around the axis of rotation of the rotating shaft; a columnar shaped pin shaft portion firmly mounted to the orbiting scroll and having a sliding contact surface, formed in a circular arc shape, for sliding contact with the wall surface of the slide groove, the distance from the central axis of the pin shaft portion to the central axis of the eccentric portion being longer than the radius of orbital movement of the orbiting scroll; wherein a portion of the pin shaft nearer to the rotating shaft than the circular arc shaped sliding contact surface which slidingly contacts the wall surface of the slide groove is cut away forming a flat side surface; and wherein rotation of the orbiting scroll is restricted by sliding contact of a wall surface of the slide groove and the pin shaft portion during orbital movement of the orbiting scroll.