Reciprocating pistons of piston-type compressor

Abstract

A piston-type fluid displacement apparatus includes a housing enclosing a crank chamber, a suction chamber, a suction chamber, and a discharge chamber. The housing includes a cylinder block wherein a plurality of cylinder bores formed, a drive shaft rotatably supported in the cylinder block and a plurality of pistons each of which is slidably disposed within one of the cylinder bores. Each of the pistons includes a cylindrical body and an arm portion axially extending from a first axial end of the cylindrical body and a pair of engaging portions formed the first axial end of the cylindrical body and the arm portion. The cylindrical body of the pistons includes an hollow portion therein. The housing further includes a plate having an angle of tilt and titably connected to the drive shaft and bearing coupling devices coupling the plate to each of the pistons, so that the pistons reciprocates within the cylinder bores upon rotation of the plate. A plurality of apertures are formed on the first axial end of the cylindrical body of the piston and fluidly communicated with the hollow portion of the piston. At least two of the apertures have respectively a rectangular shape.