Hermetically sealed rotary compressor having an oil supply passage to

Abstract

A hermetically sealed rotary compressor includes a generally cylindrical sealed vessel having an oil reservoir defined therein for accommodating a quantity of lubricating oil, a drive unit within the sealed vessel, and a compressor mechanism within the sealed vessel. The compressor mechanism includes a cylinder having a compression compartment defined therein and also having upper and lower openings, an eccentric cam provided on a crankshaft for rotation together therewith, and a ring-shaped piston mounted on the crankshaft while encircling the eccentric cam and capable of undergoing a planetary motion in contact with the eccentric cam during rotation of the eccentric cam. The cylinder has a refrigerant intake port defined therein in communication with the compression compartment. A radial vane is slidably accommodated in the cylinder for reciprocating movement in a direction radially of the cylinder and having a radial inner end held in sliding contact with an outer peripheral surface of the ring-shaped piston. An oil supply passage having first and second open ends opposite to each other is disposed with the first open end communicated with the oil reservoir via an oil pump and the second open end communicated with a low pressure chamber of the compression compartment, a portion of the oil supply passage adjacent the first end extending in a radial direction.