Scroll-type fluid machine having a sealed back pressure chamber

摘要

A scroll-type fluid machine in which the high-pressure chamber side (36) of a back pressure chamber (6a) using a fixed scroll (11) made of an aluminum base material can be fully sealed. The fixed scroll (11) is made of an aluminum base material, and a discharge cover (2) is made of a ferrous material. Between the U seals (35) interposed between the high-pressure chamber (36) side of the back pressure chamber (6a) and the low-pressure side, at least the U seal (35a) on the high-pressure chamber (36) side is made of glass-reinforced polytetrafluoroethylene resin, and is installed so as to be pressed against the fixed scroll (11). The U seal withstands a high temperature and large pressure difference and is installed so that the sliding mating part of the U seal (35a) is not the fixed scroll (11) made of an aluminum base material which is easily worn, but the discharge cover (2) made of a ferrous material which is less prone to wear.