PURPOSE: To restrain power loss caused by a balance weight by holding partition walls at predetermined positions, and by incorporating an oil cover having a leg part formed therein with a coolant passage through which high pressure cooling gas flows, in one of the partition walls.
CONSTITUTION: An oil cover 40 is composed of a peripheral wall 40a extending along a turning range 70 of a balance weight 16 fixed to the lower part of a rotor in a compressor, a partition wall 40d given by a bottom part 40b that is farmed therein with a through-hole 40c through which a main shaft 17 extends, and leg parts 40e, 40f for holding the partition wall 40d at a predetermined height, being integrally incorporated with one another. It is noted that a slight clearance which is formed between the through-hole 40c formed in the bottom part 40b and the main shaft 17 can prevent lubrication oil from flowing into a rotary space 70. As a result, the rotary space for the balance weight can be isolated by the oil cover, and accordingly, the balance weight agitates the lubrication oil, thereby it is possible to prevent power loss.
ISHIKAWA MASAKUNI
KUCHIKI SEIJI
TAMA MFG