Scroll-type compressor having a plate preventing excess lift of the crankshaft

摘要

PCT No. PCT/JP91/01417 Sec. 371 Date Sep. 3, 1991 Sec. 102(e) Date Sep. 3, 1991 PCT Filed Jun. 26, 1990 PCT Pub. No. WO91/06769 PCT Pub. Date May 16, 1991.A scroll-type compressor has a crankshaft connected to the rotor of an electric motor for causing an orbiting motion of an orbiting scroll member and having a main shaft formed at one end thereof and supported by a main bearing, an orbiting drive shaft formed on the side of an orbiting end plate opposite to an orbiting scroll wrap and received in an eccentric bearing disposed at an eccentricity in the main shaft, a rolling type upper bearing supporting the end of the crankshaft opposite to the main shaft, and a lift limiting plate fixed to the lower surface of the upper bearing to prevent excessive lift of the crankshaft. A step is formed on the crankshaft between a portion of a greater diameter at which the crankshaft is connected to the rotor, and a portion of a smaller diameter at which the crankshaft is received in the upper bearing. The compressor further has a support member resting on the inner race of the upper bearing and a fixing member by which the crankshaft is suspended and supported from the support member such that a small clearance is left between the surface of the step of the crankshaft and the lift limiting plate. This configuration suppresses the generation of noise in the upper bearing attributable to axial vibration and resonance of the shaft system.