ROTARY EXPANSION MACHINE AND REFRIGERATION CYCLE DEVICE

摘要

A rotary expansion machine (100) has three-staged expansion mechanism sections (601, 602, 603) sequentially axially arranged in a manner to share a shaft (61). The expansion mechanism sections (601, 602, 603) have cylinders (62, 63, 64), pistons (67, 68, 69) installed on the shaft (61) and eccentrically rotated inside the cylinders (62, 63, 64), and partition members (70, 71, 72) each partitioning a space between a cylinder (62, 63, 64) and a piston (67, 68, 69) into a suction side space and a discharge side space. A first operation chamber for expanding refrigerant at a first expansion ratio is formed by the discharge side space of the first expansion mechanism section (601) and the suction side space of the second expansion mechanism section (602). A second operation chamber for expanding the refrigerant at a second expansion ratio greater than the first expansion ratio is formed by the discharge side space of the second expansion mechanism section (602) and the suction side space of the third expansion mechanism section (603).