Charging valve

Claim 1

IN A CHARGING VALVE FOR PRESSURIZING UNDERWATER APPARATUS, A VALVE HOUSING HAVING A CONICAL SEAT AT ONE END THEREOF AND A CYLINDRICAL BORE THERETHROUGH EXTENDING FROM SAID SEAT TO THE OTHER END OF SAID HOUSING, AN ANNULAR SHOULDER FORMED IN SAID HOUSING BETWEEN SAID CONICAL SEAT AND SAID CYLINDRICAL BORE, SAID HOUSING HAVING MEANS AT SAID ONE END THEREOF FOR FLUID CONNECTION TO CHARGING APPARATUS, A VALVE STEM SLIDABLY MOUNTED IN SAID BORE AND HAVING A HEAD PORTION SHAPED TO BE RECEIVED IN SAID SEAT AND TO BE RAISED THEREFROM BY THE CHARGING APPARATUS WHILE A PRESSURE CHARGE IS APPLIED THERETO, SAID HEAD PORTION HAVING AN ANNULAR GROOVE THEREIN, SEALING MEANS MOUNTED IN SAID GROOVE TO ENGAGE SAID SEAT WHEN SAID HEAD PORTION IS RECEIVED THEREIN, SAID STEM HAVING A THREADED PORTION ADJACENT THE END THEREOF WITHIN SAID BORE, A NUT RETAINABLY RECEIVED ON SAID STEM THREADED PORTION, A CIRCULAR COIL SPRING OF GREATER DIAMETER THAN THE OPENING IN SAID CONICAL SEAT SURROUNDING SAID STEM AND HAVING THE ENDS THEREOF IN ABUTMENT WITH SAID ANNULAR SHOULDER AND SAID NUT RESPECTIVELY SO THAT THE INTERIOR OF SAID CIRCULAR COIL SPRING IS IN DIRECT FLUID COMMUNICATION WITH THE OPENING IN SAID CONICAL SEAT, AND A QUASI-ELLIPTICAL COIL SPRING SURROUNDING SAID STEM AND HAVING THE COILS THEREOF ALTERNATING WITH THE COILS OF SAID CIRCULAR COIL SPRING IN A MANNER TO REINFORCE THE BIAS OF THE CIRCULAR COIL SPRING AND TO ALSO PREVENT SAID CIRCULAR COIL SPRING FROM BEING COMPRESSED TO A SOLID HEIGHT AS THE HEAD PORTION OF THE VALVE IS RAISED FROM SAID SEAT BY THE CHARGING APPARATUS, WHEREBY FREE FLOW OF FLUID FROM THE CHARGING APPARATUS THROUGH THE CONICAL SEAT INTO THE INTERIOR OF THE COIL SPRING AND THEN BETWEEN THE COILS OF SPRINGS TO THE EXTERIOR OF SAID SPRINGS IS ALWAYS ASSURED.