Scroll type compressor having thrust regulation on the eccentric shaft

Abstract

A mechanism for allowing the orbital movement of an orbiting scroll with respect to a fixed scroll in a scroll type compressor which prevents the orbiting scroll from rotating around its own axis is disclosed. The orbiting scroll is eccentrically attached to a rotary shaft supported by a housing that encases the fixed and orbiting scrolls. A compression chamber is defined by the interfitting between the orbiting scroll and the fixed scroll. During the course of the orbiting scroll's rotation around the center axis line of a rotary shaft, the volume of a compression chamber decreases as the rotation progresses. Refrigerant gas in the compression chamber is compressed in this manner as the constant volume of gas within the compression chamber decreases in size according to the progression of the rotating spiral member. A balancing weight disposed on the eccentric shaft compensates for dynamic unbalancing generated as the orbiting scroll makes an orbital movement due to the rotation of the rotary shaft. This balancing weight engages a bushing which supports the orbiting scroll. A mechanism for automatically adjusting the radius of the orbital movement is disposed between the rotary shaft and the balancing weight. A spring for restricting the shifting on the eccentric shaft of both the weight and the bushing in the thrust direction is disposed between the weight and the bushing.