Scroll-type fluid machine with specific inner curve segments

摘要

A scroll-type fluid machine includes a stationary spiral element and a revolving spiral element having a substantially identical configuration and a central small chamber defined between abutting points of both the spiral elements a volume of which is adapted to be reduced to substantially zero with relative rotation of both the spiral elements. Basically, each of the both spiral elements is formed of an outer curve segment and an inner curve segment formed of involute curves and a connection inner curve expressed by a particular equation and a connection outer curve expressed by another particular equation formed between the outer and inner curve segment. The strength of the spiral elements can be enhanced or a delivery port having a large area can be provided.