Fluid pressure responsive firing device

Claim 1

A PRESSURE RESPONSIVE INITIATOR FOR DETONATION OF EXPLOSIVE CHARGES AT A PREDETERMINED DEPTH BELOW THE SURFACE OF A BODY OF WATER WHICH CONSISTS ESSENTIALLY OF A TUBULAR SHELL INTEGRALLY CLOSED AT ONE EXTREMITY, A PISTON SLIDABLY MOUNTED WITHIN AND CLOSING THE OTHER EXTREMITY OF SAID SHELL, A BASE CHARGE OF DETONATING EXPLOSIVE AND A PRIMING CHARGE OF EXPLOSIVE SEQUENTIALLY POSITIONED FROM SAID INTEGRALLY CLOSED EXTREMITY, AN ANVIL POSITIONED CONTIGUOUS TO SAID PRIMING CHARGE, SAID ANVIL COMPRISING A DIAPHRAGM SECURED IN PERIPHERAL ENGAGEMENT WITH THE INNER WALL OF SAID SHELL AND A STRIKER ARM ARRESTER EXTENDING FROM SAID DIAPHRAGM TOWARD SAID PISTON, SAID DIAPHRAGM BEING PROVIDED WITH AN APERTURE THERETHROUGH ADJACENT SAID STRIKER ARM ARRESTER, AN IGNITION CHARGE FILLING SAID APERTURE, A PERCUSSION SENSITIVE EXPLOSIVE CAP SECURED ON SAID DIAPHRAGM ADJACENT SAID APERTURE AND IN PROPAGATING RELATIONSHIP TO SAID IGNITION CHARGE, A STRIKER ARM SECURED TO SAID PISTON AND EXTENDING TO ENGAGE SAID ARRESTER, SAID ARM BEING ADAPTED TO DISENGAGE SAID ARRESTER AND STRIKE SAID PERCUSSION CAP UPON EXERTION OF A PREDETERMINED PRESSURE BY SAID PISTON, AND REMOVABLE MEANS FOR LOCKING SAID PISTON IN POSITION.