Abstract: A fractional horsepower single cylinder refrigeration compressor utilizes a discharge muffler system having a discharge plenum and a pair of muffler chambers. The muffler chambers and interconnected by a transfer tube while separate passages run from the discharge plenum directly to each of the muffler chambers. One of the muffler chambers is then connected to a discharge line to the exterior of the compressor case.

Abstract: A small hermetic refrigeration compressor of the single reciprocating piston-type has flat valve plate extending across the open end of the cylinder with a discharge port extending through the valve plate off the center line of the cylinder bore. The piston has a generally flat end face with a recess at least partially in alignment with the discharge port, to allow improved flow of gases to the discharge port with a decreased clearance volume. Further reduction of the clearance volume can be obtained by placing a projecting post on the end face of the piston in line with the discharge port to partially fill the discharge port at top dead center.