Patent ID: 6379123
Filing Date: 2002-04-30
Classification: F04C

Abstract:
A capacity-controlled scroll compressor including in a compressor housing thereof:a fixed scroll having a fixed end plate and a spiral lap erecting from the fixed end plate; an orbiting scroll having an orbiting end plate and a spiral lap erecting from said orbiting end plate and disposed in engagement with said fixed scroll with respective laps facing each other; an orbiting mechanism formed on the rear side of said orbiting end plate opposite the spiral lap of said orbiting scroll; a flat plate thrust bearing for axially supporting a thrust exerted to said orbiting scroll; and a drive shaft rotatably supported in said compressor housing with the main shaft portion thereof projecting to outside of said compressor housing passing through a shaft sealing device and a subsidiary bearing through a main bearing; and comprising; a drive transmission mechanism for transmitting the driving force from said drive shaft to said orbiting mechanism; a rotation restraining component for restraining rotation of said orbiting scroll so as to make it orbit; a revolution restraining component adjacent to said rotation restraining component for restraining the direction of motion of said rotation restraining component to the direction at right angles to said drive shaft; at least a pair of bypass holes communicating with a fluid pocket formed in between both laps by the orbiting motion of said orbiting scroll and provided at positions symmetrical with respect to said fluid pocket; a cylinder formed inside said fixed end plate in a manner communicating with said fluid pockets through said bypass holes; and a shuttle valve which can reciprocate inside said cylinder; and performing compression from the outer periphery of said both laps toward the center and the discharge capacity is made to continuously change by sequentially opening and closing said bypass holes by said shuttle valve, wherein said shuttle valve has a stepped or columnar structure having at least two different circular cross sections; and the portion connecting said steps of said stepped portion of said shuttle valve is tapered.