Patent ID: 7322809

Claim:
A rotary compressor comprising: a casing including high-pressure and low-pressure spaces; a compressing mechanism; at least one bearing disposed in the high-pressure space in the casing, the bearing having an inner peripheral face; an oil reservoir having an inside pressure that increases during operation with the low-pressure space; and a compressor motor with a drive shaft driving the compressing mechanism, the drive shaft being supported by the bearing, the drive shaft having an outer peripheral face, the drive shaft further having a main oil-supply passage and at least one bearing-portion oil-supply passage formed in the drive shaft, the main oil-supply passage connecting the oil reservoir, one end of the bearing-portion oil-supply passage being connected with the main oil-supply passage and another end of the bearing-portion oil-supply passage being connected with a sliding face constituted between the drive shaft and the bearing, the outer peripheral face of the drive shaft and the inner peripheral face of the bearing forming first and second sealing portions having substantially air-tight structures, the first sealing portion being located on a side of the bearing-portion oil-supply passage at a first interface portion between the drive shaft and the bearing and the second sealing portion being located on an opposite side of the bearing-portion oil-supply passage in an axial direction of the sliding face at a second interface portion between the drive shaft and the same bearing, at least one of the drive shaft and the bearing including an oil-supply groove connected to the bearing-portion oil-supply passage, the oil-supply groove being formed at the sliding face and located between the first and second sealing portions, and the oil-supply groove having a length in a circumferential direction of the drive shaft longer than a length of the oil-supply groove in an axial direction of the drive shaft.