Compressor having bulged bushings

A compressor in a compression mechanism comprising:

• a cylinder including a cylinder chamber and a blade groove communicating with the cylinder chamber;
• a piston including a blade that partitions the cylinder chamber into a high-pressure chamber and a low-pressure chamber and is inserted into the blade groove so as to be movable forward and backward, the piston turnably provided in the cylinder chamber;
• and
• a bush rockably accommodated in a bush hole formed in the blade groove and including a first sliding surface that slides with an inner surface of the bush hole, wherein
• the compressor in the compression mechanism includes:
• a first oil film formation portion formed on one of the first sliding surface and the inner surface such that a gap between the first sliding surface and the inner surface gradually decreases toward a direction in which lubricant is drawn between the first sliding surface and the inner surface along with rocking of the bush, and
• the first oil film formation portion includes:
• a first part formed so as to bulge on the inner surface side relative to an imaginary line constituting a curved surface in a case of assuming that the first oil film formation portion is not formed on the first sliding surface in the case where the first oil film formation portion is formed on the first sliding surface, and
• a second part formed so as to bulge on the first sliding surface side relative to an imaginary line constituting a curved surface in a case of assuming that the first oil film formation portion is not formed on the inner surface in the case where the first oil film formation portion is formed on the inner surface.