CA2046245A1 - Scroll type compressor with variable displacement mechanism - Google Patents

Abstract

A scroll type compressor with a variable displacement mechanism is disclosed which includes a housing with an inner chamber and fluid inlet and outlet ports connected to the inner chamber. A fixed scroll, which is mounted within the housing, has an end plate from which a first spiral wrap extends. An orbiting scroll also is mounted within the housing for orbital motion with respect to the fixed scroll. The orbiting scroll has an end plate from which a second spiral wrap extends. The first and second wraps interfit to define at least one pair of sealed off fluid pockets. The end plate of the fixed scroll partitions the inner chamber of the housing into a suction chamber and rear chamber. The rear chamber includes an intermediate pressure chamber which communicates with the sealed off fluid pockets through a pair of circular holes formed at the end plate of the fixed scroll. A control mechanism controls fluid communication between the intermediate pressure chamber and the suction chamber. A plurality of seal elements are sequentially located along the axial end of the second wrap such that the spaces between the seal elements cross over the circular holes during orbital motion of the orbiting scroll. Thereby, the diameter of the circular holes may be enlarged to prevent constriction of the flow of fluid through the holes during high rotational operation of the compressor, without increasing the possibility of damaging the seal elements due to the seal elements being sandwiched between the spiral wrap and the holes.