Supply and exhaust valve for a pressure chamber

Claim 1

A VALVE FOR CONTROLLING THE FLOW OF FLUID UNDER PRESSURE INTO AND OUT OF A PRESSURE CHAMBER INCLUDING A BODY HAVING A BORE, THE BORE HAVING A PRESSURE FLUID INLET AT ONE END PORTION AND AN OUTLET AT ITS OPPOSITE END PORTION AND COMMUNICATING WITH THE CHAMBER THEREBETWEEN, A VALVE MEMBER FREELY RECIPROCABLE IN SAID BORE INWARDLY OF THE INLET FOR CONTROLLING THE FLOW OF PRESSURE FLUID TO THE CHAMBER AND MOVABLE TO CLOSED POSITION SOLELY BY THE PRESSURE FLUID, A VALVE ELEMENT RECIPROCABLE IN SAID BORE ADJACENT THE OUTLET FOR CONTROLLING COMMUNICATION THEREBETWEEN, THE VALVE MEMBER HAVING A PORTION EXTENDING SLIDABLY THROUGH THE VALVE ELEMENT TO THE EXTERIOR OF THE BODY TO PERMIT MANUAL MOVEMENT OF SAID VALVE MEMBER TO OPENED POSITION AND ENGAGEABLE WITH SAID VALVE ELEMENT TO HOLD THE SAME IN OPENED POSITION WHEN SAID VALVE MEMBER IS CLOSED, AND SPRING MEANS FOR HOLDING SAID VALVE ELEMENT IN CLOSED POSITION WHEN SAID VALVE MEMBER IS OPENED AND ASSISTING IN HOLDING SAID VALVE MEMBER OPENED DUE TO THE AFORESAID ENGAGEMENT, THE SPRING MEANS PERMITTING OPENING MOVEMENT OF SAID VALVE ELEMENT BY THE PRESSURE FLUID WHENEVER THE FLUID IN SAID BORE EXCEEDS A PREDETERMINED PRESSURE DUE TO MANUAL HOLDING OF SAID VALVE MEMBER IN ITS OPENED POSITION THE OPENING MOVEMENT OF SAID VALVE ELEMENT DISENGAGING SAID VALVE ELEMENT FROM SAID VALVE MEMBER TO PERMIT CLOSING MOVEMENT OF SAID VALVE MEMBER BY THE PRESSURE FLUID AND REENGAGEMENT OF SAID VALVE MEMBER WITH SAID VALVE ELEMENT TO MOVE SAID VALVE ELEMENT TO OPENED POSITION WHEN SAID VALVE MEMBER IS RELEASED.