Pressure relief valve

Claim 1

APRESSURE RELIEF VALVE COMPRISING; (A) A BODY INCLUDING A CHAMBER, (B) FIRST AND SECOND PASSAGES ON SIAD BODY COMMUNICATING WITH SAID CHAMBER, (C) A FIRST VALVE ELEMENT CONNECTED TO SAID BODY AND INCLUDING A TAPERING END PORTION PROJECTING INTO SAID CHAMBER, (D) A SECOND RING VALVE EMENT PROJECTING INTO SAID CHAMBER AND COMMUNICATING WITH ONE OF SAID FIRST MENTIONED PASSAGES, (E) SAID RING VALVE ELEMENT HAVING AN OPEN END ENGAGED BY SAID PROJECTING PORTION IN MATING RELATION TO RESTRICT THE PASSAGE OF FLUID THROUGH SAID CHAMBER AND BETWEEN SAID PASSAGES, (F) SAID RING VALVE ELEMENT BEING LONGITUDINALLY RETRACTABLE IN RESPONSE TO FLUID PRESSURE WITH RESPECT TO SAID PROJECTING PORTION TO PROVIDE FOR THE FLOW OF FLUID FROM ONE PASSAGE THROUGH SAID CHAMBER TO SAID OTHER PASSAGE, (G) SAID RING VALVE ELEMENT HAVING FLUID PRESSURE RESPONSIVE MEANS CONTAINED THEREIN WHICH DURING A PREDETERMINED FLUID PRESSUR ON ONE OF SAID PASSAGES RETRACTS SAID CYLINDRICAL VALVE ELEMENT RELATIVE TO SAID PROJECTING PORTION, (H) SAID RING VALVE ELEMENT COMPRISING A FIRST PORTION OF LARGE DIAMETER AND ANOTHER PORTION OF A REDUCED DIAMETER CONNECTED TO SAID FIRST PORTION TO PROVIDE THEREBETWEEN AN ANNULAR SHOULDER DEFINING SAID FLUID PRESSURE RESPONSIVE MEANS, SAID PORTION OF REDUCED DIAMETER BEING DISPOSED NEAREST TO SAID TAPERING PORTION AND SAID SHOULDER IS DISPOSED OUTSIDE OF SAID RING VALVE ELEMENT IN SAID CHAMBER, SAID TAPERING PORTION BEING INWARDLY DISHED AND IN SEALING ENGAGEMENT WITH SAID RING VALVE ELEMENT.