Valved safety device

Claim 1

A COMBINATION SAFETY DEVICE FOR PREVENTING THE FORMATION OF EXPLOSIVE GAS MIXTURES AND THE FURTHER DEVELOPMENT OF EXPLOSIONS IN BURNER GAS PIPES, COMPRISING A HOUSING, A GAS INLET AND A SPACED GAS OUTLET IN SAID HOUSING, A FLAME TRAP ARRANGED WITHIN SAID HOUSING BETWEEN SAID INLET AND SAID OUTLET, AN EXCESS-PRESSURE RELIEF OPENING LEADING OUT OF SAID HOUSING ON THAT SIDE OF SAID FLAME TRAP CLOSER TO SAID OUTLET, AN EXCESS-PRESSURE RELIEF VALVE IN SAID RELIEF OPENING, A BACK-PRESSURE CHECK VALVE ARRANGED WITHIN SAID HOUSING ON THAT SIDE OF SAID FLAME TRAP CLOSER TO SAID INLET, SAID CHECK VALVE COMPRISING A MOVABLE DOUBLE-ACTING CHECK VALVE ELEMENT, A FURTHER VALVE CONTROLLING THE FLOW OF GAS THROUGH SAID INLET, LOCKING MEANS ARRANGED TO LOCK SAID FURTHER VALVE IN AN OPENING POSITION, MEANS OPERATIVELY CONNECTING SAID CHECK VALVE ELEMENT WITH SAID LOCKING MEANS WHEREBY SAID CHECK VALVE ELEMENT IS ADAPTED TO TRIGGER THE RELEASE OF SAID LOCKING MEANS, AND TWO VALVE SEATS FOR SAID CHECK VALVE ELEMENT WHEREBY SAID VALVE ELEMENT IS ARRANGED TO CLOSE ON ONE SEAT IN ONE DIRECTION OF GAS-FLOW AND TO CLOSE ON THE OTHER VALVE SEAT IN THE OPPOSITE DIRECTION OF GAS-FLOW.