Bearing device for scroll-type compressor

摘要

In a scroll-type compressor, the sum of pressure receiving areas of the upper end surfaces of crank portion of a crankshaft and the upper end surface of a balance weight is made substantially equal to the sum of the pressure receiving areas of the lower end surface of the shaft portion of the crankshaft and the lower end surface of the balance weight, the surfaces being subjected to internal pressures of the compressor. Consequently, only the downward force produced by the weights of the crankshaft and the rotor of a driving motor is applied to the crankshaft as an axial load which is born by a thrust bearing. Since the thrust bearing is required only to bear a small thrust load, it is free from the problems such as rapid wear and seizure.