PURPOSE: To prevent the lowering of volumetric efficiency of a compressor by making a projected part, which is formed in an outer surface of a rolling piston, go into a discharge opening of refrigerant gas.
CONSTITUTION: A projected part 21a is formed in an outer surface of a rolling piston 21. In addition, a rotary joint is formed with both a tip part 22a of a vane 22 and a groove 21b. With this, the rolling piston 21 revolves round the center with respect to an eccentric part 4a of a crank shaft without autorotation, and the position of the projected part 21a always projects itself into a discharge opening 10 at the time of a discharge stroke of refrigerant gas. Meanwhile, the refrigerant gas is discharged from a gap between the projected part 21a and the discharge opening 10 via a discharge valve 11. Accordingly, the amount of the refrigerant gas remaining in the dead volume within the discharge opening 10 can be made minimum, and therefore the lowering of volumetric efficiency due to reexpansion of the remaining gas at the subsequent stage can be made minimum.
TSUNODA MASAYUKI
KITORA YOSHIHISA
HIRAI TETSUO
