PURPOSE: To reduce a surplus work quantity of a compressor through prevention of the occurrence of interference of a balancer with lubricating oil and to decrease the generation of noise, by a method wherein lubicating oil in a cover with high the balancer is covered can be discharged.

CONSTITUTION: A balancer 8 is located to the lower end of a rotary shaft 6 of a vertical rotary type enclosure type compressor, and a cover 9, adapted to partition a balancer 8 from lubricating oil, is provided. A passage 24, having the one end open to the inner bottom part of the cover 9 and the other and open to the suction side 4b of a compressor part 3, is provided. A suction pres sure is exerted on the passage 24, and this causes discharge of lubricating oil gathering to the inner bottom of the cover 9.