Refrigerant gas compressor construction

Abstract

A compressor asssembly, with particular reference to the suction side thereof, for a gas compressor having one or more cylinders, pistons mounted for reciprocation in the cylinders, cylinder head means mounted over the ends of the cylinders to provide discharge chambers, refrigerant discharge valve elements intermediate the head means and cylinders and providing compression chambers and adapted to open discharge passages to the discharge chambers for pressurized gas on the compression strokes of the pistons and to close the discharge passages on the suction strokes of the pistons, first suction gas inlet passages through the walls of the cylinders at positions remote from the cylinder head means, second suction gas inlet passages in the pistons extending through the outer walls thereof and in communication with the first passages over at least substantial portions of the travels of the pistons, suction gas ports in the tops of the pistons in communication with the second passages, the ports having port seats defining apertures through the tops of the pistons, and valve discs mounted in the upper portions of the pistons for limited axial, floating movement and having sealing surfaces or disc seats adapted to bear against the port seats on the compression strokes of the pistons to close off the second passages from the compression chambers, the floating movement being sufficient for movement of the disc seats away from the port seats to provide the suction gas ports with suitable open dimensions to allow adequate low-pressure refrigerant gas flow into the compression chambers during the suction stroke of the pistons.