Patent ID: 6361288
Filing Date: 2002-03-26
Classification: F04B,Y10T

Abstract:
An unloader system for a reciprocating compressor including a cylinder, a piston reciprocably mounted in the cylinder, a rotatable crankshaft connected to the piston, a suction line, a discharge line, a suction valve assembly, and a discharge valve assembly for selectively communicating the suction and discharge lines respectively with the compressor cylinder, and a cycle with compression and re-expansion strokes, which unloader system comprises:a. an unloader valve assembly having an inboard side and an outboard side, said inboard side communicating with said compressor cylinder; b. means for varying the unloading of the compressor to a desired level by adjustably and automatically opening said unloader valve assembly during said compression stroke and closing said unloader valve assembly during said re-expansion stroke, said means for varying being connected to said compressor and being adapted to actuate said unloader valve assembly in response to an operating condition of the compressor; and c. A clearance cavity in selective communication with said compressor cylinder through said unloader valve assembly.