Patent ID: 6105504
Filing Date: 2000-08-22
Classification: F42C

Abstract:
An actuating circuit for a contact exploder comprising:a charging circuit including a charge-discharge capacitor;an insulated sensing conductor;means operatively connecting the sensing conductor to the charging circuit for holding the charging circuit in a quiescent condition until the occurrence of at least one of the following:(1) the insulated sensing conductor opens,(2) a portion of the insulation of the insulated sensing conductor is removed and the sensing conductor is shorted;the charging circuit, which is adapted for connection to a direct-current power supply, comprising:a differential amplifier, comprising two transistors whose emitters are connected together to a grounded resistor, and whose collectors are connected to the direct-current power supply;one of the transistors, the first differential transistor, being based biased;the other transistor, the second differential transistor, having a base which is connected to a grounded resistor and one end of the second conductor, the other end of the sensing conductor being connected to a grounded resistor;a pulse-forming transistor, whose emitter is connected to the direct-current power supply, whose base is connected to the collector of the first differential transducer, and whose collector is connected to a grounded resistor;a silicon-controlled rectifier (SCR), whose anode is connected to the direct-current power supply, whose gate is connected to the collector of the pulse-forming transistor, and whose cathode is connected to one end of a squib detonating wire, the other end of the squib being connected through an RC combination to ground, one end of the charge-discharge capacitor being connected to the anode of the SCR, the other end being connected to the junction of the squib and the RC combination;the following sequence of events occurring if the sensing conductor is either opened or grounded, after a voltage had been applied to the charging circuit; the second differential transistor becomes nonconducting, the first differential transistor begins to conduct, causing collector current to flow in the pulse-forming transistor, which causes a positive pulse to appear at the gate of the silicon-controlled rectifier, forcing it to fire, thereby dumping the charge which had accumulated on the discharge capacitor through the squib detonating wire.