Air valve

Claim 1

AN EXHAUST VALVE COMPRISING A BODY HAVING AN AXIAL BORE PROVIDING AXIALLY SPACED INLET AND UTILIZATION PORTS, AN INLET VALVE SEAT SURROUNDING THE INLET PORT AND A UTILIZATION VALVE SEAT SURROUNDING THE UTILIZATION PORT, A SHUTTLE VALVE COMPRISING A HOLLOW CYLINDER SLIDABLY MOUNTED IN SAID BORE AND HAVING A PAIR OF SEALING SURFACES SPACED AXIALLY CLOSER TOGETHER THAN THE SPACING BETWEEN SAID SEATS AND ADAPTED TO MAKE SEALING ENGAGEMENT WITH SAID SEATS RESPECTIVELY UPON SLIDING MOVEMENT OF THE CYLINDER, SAID UTILIZATION VALVE SEAT BEING FLAT AND SUBSTANTIALLY NORMAL TO THE AXIS OF THE BORE AND THE VALVE SEALING SURFACE ENGAGEABLE THEREWITH BEING A PORTION OF THE END WALL OF THE CYLINDER AND BEING THEREFORE ALSO FLAT AND SUBSTANTIALLY NORMAL TO THE AXIS OF THE BORE, WHEREBY SAID LAST NAMED SEALING SURFACE WILL BE UNSEATED FROM SAID UTILIZATION VALVE SEAT SUBSTANTIALLY IMMEDIATELY UPON INCIPIENT MOVEMENT OF SAID SHUTTLE VALVE TOWARD SAID INLET PORT, CHECK VALVE MEANS CARRIED BY SAID SHUTTLE VALVE OPENABLE UPON MOVEMENT OF THE SHUTTLE VALVE TOWARD THE UTILIZATION VALVE SEAT AND CLOSABLE UPON MOVEMENT OF THE SHUTTLE VALVE TOWARD THE INLET VALVE SEAT, AN EXHAUST CONDUIT COMMUNICATING WITH THE BORE OF THE BODY BETWEEN THE TWO SEATS THEREOF SO AS TO BE OPEN TO THE UTILIZATION PORT WHEN THE UTILIZATION VALVE SEALING SURFACE OF THE SHUTTLE VALVE IS UNSEATED FROM THE UTILIZATION VALVE SEAT AND BE CLOSED FROM THE UTILIZATION PORT WHEN THE UTILIZATION VALVE SEALING SURFACE OF THE SHUTTLE VALVE IS SEATED ON THE UTILIZATION VALVE SEAT, AND ADJUSTABLE MEANS FOR CONTROLLING THE OUTLET FROM SAID EXHAUST CONDUIT.