Vacuum relief, pressure relief valve

Claim 1

A PRESSURE-RELIEF VACUUM-RELIEF VALVE ADAPTED FOR USE WITH A CONTAINER HAVING A VENT OPENING, COMPRISING A HOLLOW HOUSING INCLUDING A TUBULAR EXTENSION ADAPTED FOR CONNECTION WITH SAID VENT OPENING TO AFFORD COMMUNICATION BETWEEN SAID CONTAINER AND SAID HOUSING; A DIAPHRAGM MOUNTED IN SAID HOUSING AND DEFINING FIRST AND SECOND CHAMBERS THEREIN, SAID SECOND CHAMBER BEING IN COMMUNICATION WITH SAID CONTAINER THROUGH SAID TUBULAR EXTENSION; TRANSVERSE WALL MEANS SECURED TO SAID TUBULAR EXTENSION INTERMEDIATE SAID SECOND CHAMBER AND SAID CONTAINER, SAID TRANSVERSE WALL MEANS CONTAINING A FIRST VALVE SEAT OPENING; A HOLLOW VALVE MEMBER MOUNTED FOR AXIAL SLIDING MOVEMENT IN SAID VALVE SEAT OPENING TO OPEN AND CLOSE THE PASSAGE THERETHROUGH; SAID HOLLOW VALVE MEMBER EXTENDING AT ONE END IN SAID SECOND HOUSING CHAMBER AND CARRYING AT ITS FREE END A SECOND VALVE SEAT ADJACENT SAID DIAPHRAGM, SAID HOUSING CONTAINING OPENINGS AFFORDING CONTINUOUS COMMUNICATION BETWEEN SAID SECOND CHAMBER AND THE REGION EXTERNAL OF SAID HOUSING; SPRING MEANS BIASING SAID VALVE MEMBER IN ONE DIRECTION TOWARD A POSITION CLOSING SAID FIRST VALVE OPENING, SAID DIAPHRAGM BEING ARRANGED FOR SEATING EN-