Scroll type compressor having gradually thinned wall thickness

摘要

A scroll type compressor has a stationary scroll (1) and a movable scroll (2) rotating around the former in an orbital manner, while forming volume variable sealed spaces therebetween to compress a coolant gas. To reduce a wall thickness of the scroll, an outer wall curve (E.sub. 1.sup.+) of the scroll (1,2) is defined by the modification of a basic involute curve (D.sup.+) by reducing a certain value B&thgr;.sup.n) from a length (L.sub.0) of the respective involute line of the basic involute curve, which value is increased as the involute angle (&thgr;) is developed, and an inner wall curve (E.sub.1.sup.-) is generated from the outer wall curve (E.sub.1.sup.+) by first transferring the respective point (p.sub.3, 4) on the outer wall curve (E.sub.1.sup.+) in the normal direction to the outer wall curve (E.sub.1.sup.+) at the respective point (p.sub.3, 4) by a distance (r) equal to a radius of the orbital circle (R) to form an intermediate curve (E.sub.1) and then symmetrically transferrring the respective point (p.sub.5) on the intermediate curve (E. sub.1) around the center (O.sub.1) of the basic circle (C.sub.1).