Electric switch with frangible and expendable electrodes

Claim 1

AN ELECTRIC SWITCH COMPRISING AN INNER AND METALLIC LAYER SANDWICHED BETWEEN FIRST AND SECOND LAYERS OF ELECTRICALLYINSULATING MATERIAL WHICH IN TURN ARE SANDWICHED BETWEEN TWO EXPANDABLE ELECTRODES, TWO MAIN ELECTRODES BETWEEN WHICH THE SANDWICH IS HELD SUCH THAT THE TWO MAIN ELECTRODES CONTACT THE TWO EXPENDABLE ELECTRODES RESPECTIVELY, THE ELECTRIC SUPPLY TO THE SWITCHED BEING ARRANGED TO BE CONNECTED ACROSS THE MAIN ELECTRODES, AN APERTURE EXTENDING THROUGH THE FIRST LAYER SUBSTANTIALLY NORMAL TO THE GENERAL PLANE OF THE SANDWICH, A PAIR OF ALIGNED APERTURES IN THE MAIN ELECTRODES SUBSTANTIALLY NORMAL TO THE GENERAL PLANE OF THE SANDWICH, A PLUNGER, AND MEANS OPERATED WHEN THE SWITCH IS TO BE CLOSED TO CAUSE AN ELECTRIC DISCHARGE FROM ONE MAIN ELECTRODE VIA THE APERTURE IN THE FIRST LAYER TO THE INNER METALLIC LAYER WHEREBY SAID SECOND LAYER IS RUPTURED AND AN ELECTRIC, PATH IS THEREBY COMPLETED BETWEEN THE MAIN ELECTRODES, SAID MEANS ALSO CAUSING THE PLUNGER TO BE FORCED INTO THE APERTURE IN THE MAIN ELECTRODE SUCH THAT THE SANDWICH IS PIERCED AND DEFORMED PORTIONS OF THE EXPENDABLE ELECTRODES ARE IN CONTACT AND COMPLETE A LOW RESISTEANCE ELECTRIC PATH BETWEEN THE MAIN ELECTRODES.