Patent ID: 7021912

Claim:
A scroll fluid machine comprising: a stationary scroll member; an orbiting scroll member to mesh with the stationary scroll member; a driver for driving the orbiting scroll member via a crankshaft having an eccentric pin portion; a frame joined with the stationary scroll member and having a shaft support to support the crankshaft, the shaft support for the crankshaft being arranged only on a side closer to the orbiting scroll member than the driver; an Oldham's ring for preventing the orbiting scroll member from rotating on its axis; a closed vessel receiving these elements; a space formed by the frame, the stationary scroll member, and the orbiting scroll member; a further frame provided in the space to be separable from the frame; a shaft support of the orbiting scroll member to engage with the eccentric pin portion of the crankshaft; a seal portion formed between an end surface of the shaft support of the orbiting scroll member and the further frame to divide the space into a central space substantially under a discharge pressure and an outer peripheral space under a lower pressure than that in the central space; an oil feed system, by which a lubricating oil accumulated in the closed vessel is supplied to the shaft support for the crankshaft and the shaft support of the orbiting scroll member; and a space, in which a balance weight is arranged, formed between the frame and the further frame to be communicated to the central space.