Exploders

Claim 1

AN EXPLODER FOR FIRING ELECTRIC DETONATORS AND THE LIKE, WHICH COMPRISES IN COMBINATION, A PAIR OF OUTPUT TERMINALS, A SOURCE OF ELECTRICAL ENERGY HAVING TWO POLE PIECES AT DIFFERENT ELECTRICAL POTENTIAL, ONE OF THE SAID POLE PIECES BEING COUPLED TO ONE OF THE SAID OUTPUT TERMINALS, TWO RESISTORS, ONE OF WHICH IS A BALLAST RESISTOR AND THE OTHER A REFERENCE RESISTOR, ELECTRICALLY CONNECTED AT A JUNCTION, THE OTHER END OF THE BALLAST RESISTOR BEING CONNECTED TO THE OTHER POLE PIECE AND THE OTHER END OF THE REFERENCE RESISTOR BEING ALSO CONNECTED TO THE SAID OTHER OUTPUT TERMINAL, AT LEAST ONE CONTROL RESISTOR HAVING A BASE ELECTRODE AND TWO OTHER ELECTRODES, AND A CONSTANT VOLTAGE DEVICE HAVING TWO ELECTRICAL LEADS, ONE OF THE SAID LEADS BEING COUPLED TO THE BASE ELECTRODE OF THE SAID TRANSISTOR AND THE OTHER BEING COUPLED TO THE SAID OTHER OUTPUT TERMINAL, ONE OF THE TWO OTHER ELECTRODES OF THE TRANSISTOR BEING COUPLED TO THE SAID JUNCTION BETWEEN THE SAID TWO RESISTORS AND THE OTHER BEING COUPLED TO THE SAID ONE OUTPUT TERMINAL, THE RESISTANCE OF SAID BALLAST RESISTOR BEING CHOSEN IN ACCORDANCE WITH THE CHARACTERISTICS OF THE SAID CONTROL TRANSISTOR, THE POTENTIAL DIFFERENCE BETWEEN THE SAID POLE PIECES, THE RESISTANCE OF THE EXTERNAL DETONATOR CIRCUIT, AND THE DESIRED OUTPUT CURRENT, THE RESISTANCE OF THE SAID REFERENCE RESISTOR AND THE CHARACTERISTIC VOLTAGE OF THE SAID CONSTANT VOLTAGE DEVICE BEING CHOSEN IN ACCORDANCE WITH THE DESIRED OUTPUT CURRENT.