Patent ID: 6209444
Filing Date: 2001-04-03
Classification: F04B

Abstract:
A piston-operated refrigerant compressor comprising:a cylinder block having a central axis and a plurality of cylinder bores arranged in parallel with one another and equiangulary around the central axis;a drive shaft rotatably supported in a central portion of said cylinder block and supporting thereon a cam plate to be rotatable together with said drive shaft within a crank chamber; anda plurality of pistons fitted in said cylinder bores of said cylinder block to be reciprocated in said cylinder bores in association with the rotation of said cam plate, each of said plurality of pistons being fitted with a piston ring in a circumferential groove formed therein,wherein said cylinder block is centrally provided with an inner end face confronting an interior of said crank chamber and having bore ends of said plurality of cylinder bores lying therein, said inner end face being centrally provided with a boss portion axially projecting into the interior of said crank chamber and defining a circularly extending lip portion of each of said bore ends of said cylinder bores to urge said piston together with said piston ring into the corresponding cylinder bore when assembling said piston and said piston ring into the corresponding cylinder bore.