Explosive type switch with circuit serving means

Claim 1

A device for severing a mechanical element comprising an electrical current conductor including a cylindrical portion and a coaxial annular portion extending outwardly from said cylindrical portion, the internal diameter of the annular portion being approximately equal to the external diameter of said cylindrical portion, said device comprising an explosive charge having an energy per unit of mass in excess of 1,000 joules/gram and a speed of propagation in excess of 3,000 ms, firing means for detonating said charge, housing means for housing and supporting the mechanical element and said explosive charge including a first electrical terminal connected to said annular portion of said mechanical element and a second electrical terminal connected to said cylindrical portion of said mechanical element, said mechanical element including means for initiating fracture comprising means defining first and second coaxial grooves located in the area joining said cylindrical portion and said annular portion, and said cylindrical portion including recess means for housing said explosive charge and said firing means such that the initial volume presented to the explosive gases, defined by the volume of said explosive charge and the housing therefor, is no greater than thE volume swept by the gas during the useful displacement of the sheared portion of the mechanical element to be severed, said swept volume being equivalent to the volume of a cylinder having a diameter equal to the internal diameter of the annular portion and a height equal to the distance between the said first and second coaxial grooves.

Claim 2

A device for severing a mechanical element comprising an electrical current conductor including a cylindrical portion and a coaxial annular portion extending outwardly from said cylindrical portion, the internal diameter of the annular portion being approximately equal to the external diameter of said cylindrical portion, said device comprising an explosive charge having an energy per unit of mass in excess of 1,000 joules/gram and a speed of propagation in excess of 3,000 ms, firing means for detonating said charge, housing means for housing and supporting the mechanical element and said explosive charge including a first electrical terminal connected to said annular portion of said mechanical element and a second electrical terminal connected to said cylindrical portion of said mechanical element, said mechanical element including means for initiating fracture comprising means defining first and second coaxial grooves located in the area joining said cylindrical portion and said annular portion, and said cylindrical portion including recess means for housing said explosive charge and said firing means such that the initial volume presented to the explosive gases, defined by the volume of said explosive charge and the housing therefor, is no greater than thE volume swept by the gas during the useful displacement of the sheared portion of the mechanical element to be severed, said swept volume being equivalent to the volume of a cylinder having a diameter equal to the internal diameter of the annular portion and a height equal to the distance between the said first and second coaxial grooves.

Claim 7

A device for severing a mechanical element comprising a current carrying conductive strip, said device comprising an explosive charge having an energy per unit of mass in excess of 1,000 joules/gram and a speed of propagation in excess of 3,000 ms, firing means for detonating said charge, means for housing the mechanical element to be severed including a conductive case and an insulating cover secured to said case, the said current carrying conductive strip extending through said cover, said housing means further comprising a conductive member located within said case and including means for housing said explosive charge and a conductive anvil member which is displaced responsive to ignition of said charge and an insulating member located between said anvil member and said conductive strip; the initial volume presented to the explosive gases defined by the volume of said explosive charge and the housing therefor being no greater than the volume swept by the gas during the useful displacement of the sheared portion of the element to be severed, said swept volume being equivalent to the volume of the cylinder having a diameter equal to the internal diameter of the anvil housing means and a height equal to the thickness of the element to be severed.

Claim 8

A device for severing a mechanical element comprising a current carrying conductive strip, said device comprising an explosive charge having an energy per unit of mass in excess of 1,000 joules/gram and a speed of propagation in excess of 3,000 ms, firing means for detonating said charge, means for housing the mechanical element to be severed including a conductive case and an insulating cover secured to said case, the said current carrying conductive strip extending through said cover, said housing means further comprising a conductive member located within said case and including means for housing said explosive charge and a conductive anvil member which is displaced responsive to ignition of said charge and an insulating member located between said anvil member and said conductive strip; the initial volume presented to the explosive gases defined by the volume of said explosive charge and the housing therefor being no greater than the volume swept by the gas during the useful displacement of the sheared portion of the element to be severed, said swept volume being equivalent to the volume of the cylinder having a diameter equal to the internal diameter of the anvil housing means and a height equal to the thickness of the element to be severed.