SCROLL TYPE FLUID MACHINE

摘要

To provide a scroll type fluid machine which can ensure that even when the pressure ratio of the pressure P1 of its high pressure chamber (back pressure chamber) to the pressure P2 of its low pressure chamber (P1/P2) is low, its orbiting scroll be pressed against its fixed scroll without having its orbiting scroll increased in diameter to prevent any leakage of a fluid through between the front end face of the wall of its orbiting scroll and the bottom face of the end plate of its fixed scroll. The scroll type fluid machine has an Oldham's keyway (17) formed along the edge of the back side of the orbiting scroll end plate (13a) for holding one end portion of an Oldham's ring (10) slidably, and a sealing member (18) has a tongue part (18a) formed to cut off the flow of any fluid from the back pressure chamber to the Oldham's keyway (17).