Electric overvoltage arrester with large capacitive spark gap

Claim 1

AN ELECTRIC OVERVOLTAGE ARRESTER COMPRISING: FIRST SPARK GAP MEANS HAVING TWO ELECTRODES WHICH REMAIN SUBSTANTIALLY UNAFFECTED WHEN SUBJECTED TO AN ELECTRIC ARC, ONE OF SAID TWO ELECTRODES OF SAID FIRST SPARK GAP MEANS PROVIDED FOR CONNECTION TO A LINE OF HIGH ELECTRICAL VOLTAGE POTENTIAL RELATIVE TO GROUND; AND SECOND SPARK GAP MEANS HAVING A LARGE CAPACITANCE AND COMPRISING AN INSULATOR MEMBER, A FIRST ELECTRODE ON ONE SIDE OF SAID INSULATOR MEMBER, SAID INSULATOR MEMBER BEING CONNECTED TO THE OTHER ONE OF SAID TWO ELECTRODES OF SAID FIRST SPARK GAP MEANS, A SECOND ELECTRODE ON SAID ONE SIDE OF SAID INSULATOR MEMBER AND DEFINING AN ELECTRICALLY NON-CONDUCTIVE, NARROW AND ELONGATED GAP WITH SAID FIRST ELECTRODE ON SAID MEMBER, SAID SECOND ELECTRODE ON SAID MEMBER BEING CONNECTED TO GROUND, AND AN ELECTRIC CONDUCTIVE LAYER ON THE OTHER SIDE OF SAID MEMBER BENEATH SAID FIRST AND SECOND ELECTRODES THEREON, AT LEAST ONE OF SAID FIRST AND SECOND ELECTRODES ON SAID MEMBER BEING CONSUMABLE WHEN SAID SECOND SPARK GAP MEANS IS SUBJECTED TO AN ELECTRIC ARC.