Compressor construction with inertial suction valve

Claim 1

IN A REFRIGERATION COMPRESSOR, A COMPRESSION CYLINDER INCLUDING A PISTON CHAMBER, A PISTON RECIPROCABLE IN SAID CYLINDER, DRIVE MEANS FOR RECIPROCATING SAID PISTON, A HOLLOW BODY ON SAID PISTON, SAID BODY BEING ADAPTED TO COMMUNICATE AT ONE END WITH A COLUMN OF SUCTION GAS, A PISTON HEAD ON SAID PISTON BODY AT THE OPPOSITE END RECIPROCABLE IN SAID PISTON CHAMBER, SAID PISTON HEAD HAVING A HUB THEREIN, MEANS FORMING A SUCTION VALVE PORT IN SAID PISTON HEAD, AN INERTIALLY RECIPROCABLE POPPET SUCTION VALVE CONSTRUCTED OF POLYTETRAHALOGENETHYLENE MATERIAL AND INCLUDING A RELATIVELY SHORT STEM FREELY SLIDABLY MOUNTED IN SAID HUB IN SAID PISTON HEAD, AND KEEPER MEANS ON SAID STEM FOR RETAINING SAID STEM IN SAID HUB, SAID SUCTION VALVE BEING NORMALLY BIASED OPEN AND BEING ADAPTED TO CLOSE DURING THE COMPRESSION STROKE, WHEREBY THE CYLINDER IS UNLOADED AT START-UP AND DOES NOT BEGIN TO LOAD UNTIL THE INERTIA FORCES AND THE RESISTANCE OF THE GAS IN THE PISTON CHAMBER TO COMPRESSION ARE SUFFICIENT TO CLOSE SAID SUCTION VALVE.