Fuze with electronic sterilization
View Patent ↗A fuze may include a detonator, a firing capacitor and a control circuit. The firing capacitor may be charged to a nominal operational voltage, wherein when the firing capacitor is discharged across the detonator, an external explosive charge may be detonated. The firing capacitor may also be charged to a sterilization voltage, wherein when the firing capacitor is discharged across the detonator, the detonator may be destroyed without causing detonation of an external explosive charge. When the detonator is destroyed, the sterilized fuze is unable to trigger detonation of an external explosive charge.
1. A fuze comprising:
an exploding foil initiator comprising a foil bridge and an explosive;
a firing capacitor; and
a control circuit arranged to charge the firing capacitor and to discharge the firing capacitor across the exploding foil initiator;
wherein the control circuit charges the capacitor to a sterilization voltage, and when the capacitor is discharged across the exploding foil initiator, the foil bridge is destroyed without causing detonation of the explosive.
2. The fuze of claim 1 , wherein the control circuit is arranged to charge the capacitor to a nominal operational voltage, and when the capacitor is discharged across the exploding foil initiator, the explosive is detonated.
3. The fuze of claim 1 , wherein the exploding foil initiator has a predetermined maximum acceptable safe stimulus level, and when the firing capacitor is charged to the sterilization voltage and discharged across the exploding foil initiator, the stimulus provided to the exploding foil initiator is less than the predetermined maximum acceptable safe stimulus level.
4. The fuze of claim 1 , wherein the exploding foil initiator has a predetermined maximum acceptable safe stimulus level, and when the firing capacitor is charged to a nominal operational voltage and discharged across the exploding foil initiator, the stimulus provided to the exploding foil initiator is greater than the predetermined maximum acceptable safe stimulus level.
5. A fuze comprising:
a firing capacitor;
a detonator having an explosive; and
a logic control circuit arranged to control a high voltage circuit and a trigger circuit;
wherein the high voltage circuit is arranged to charge the firing capacitor, and when the trigger circuit is activated, the firing capacitor discharges across the detonator; and
wherein the high voltage circuit is arranged to charge the firing capacitor to a sterilization voltage, and when the firing capacitor discharges across the detonator at the sterilization voltage, the detonator is destroyed without causing detonation of the explosive.
6. The fuze of claim 5 , wherein the high voltage circuit is arranged to charge the firing capacitor to a nominal operational voltage, and when the firing capacitor discharges across the detonator at the nominal operational voltage, the explosive is detonated.
7. The fuze of claim 6 , further comprising a feedback circuit which indicates to the logic circuit the voltage of the firing capacitor.
8. The fuze of claim 7 , wherein the feedback circuit further comprises a normal voltage verification line.
9. The fuze of claim 7 , wherein the feedback circuit further comprises a sterilization voltage verification line.
10. The fuze of claim 6 , wherein the logic control circuit further comprises reference voltage source, a reference voltage receiving circuit controlling the high voltage circuit, and a switch controlled by the logic circuit;
wherein at a first switch position, the reference voltage source is arranged to output a first reference voltage to the reference voltage receiving circuit, and the reference voltage receiving circuit instructs the high voltage circuit to provide the nominal operational voltage to the firing capacitor; and
wherein at a second switch position, the reference voltage source is arranged to output a second reference voltage to the reference voltage receiving circuit, and the reference voltage receiving circuit instructs the high voltage circuit to provide the sterilization voltage to the firing capacitor.
11. The fuze of claim 6 , wherein the trigger circuit activates a firing switch that shorts the firing capacitor across the detonator.
12. The fuze of claim 11 , wherein the firing switch comprises an n-channel MOS-controlled thyristor.
13. The fuze of claim 5 , wherein the detonator comprises an exploding foil initiator.
14. The fuze of claim 13 , wherein the exploding foil initiator has a predetermined maximum acceptable safe stimulus level, and when the firing capacitor is charged to the sterilization voltage and discharged across the exploding foil initiator, the stimulus provided to the exploding foil initiator is less than the predetermined maximum acceptable safe stimulus level.
15. The fuze of claim 13 , wherein the exploding foil initiator has a predetermined maximum acceptable safe stimulus level, and when the firing capacitor is charged to the nominal operational voltage and discharged across the exploding foil initiator, the stimulus provided to the exploding foil initiator is greater than the predetermined maximum acceptable safe stimulus level.
16. The fuze of claim 5 , further comprising a receiver in communication with the logic circuit which receives a sterilization instruction.
17. A fuze for an explosive, the fuze comprising:
an exploding foil initiator; and
a control circuit having a first state and a second state;
wherein in the first state, the control circuit provides a nominal voltage to the exploding foil initiator, the nominal voltage being sufficient to detonate the explosive, and in the second state, the control circuit provides a sterilization voltage to the exploding foil initiator, the sterilization voltage being sufficient to destroy the exploding foil initiator without causing detonation of the explosive.
18. The fuze of claim 17 , wherein the exploding foil initiator comprises a bridge foil, a flyer and an explosive.
19. The fuze of claim 18 , wherein when the nominal voltage is provided to the exploding foil initiator, the bridge foil is vaporized, and a portion of the flyer is propelled into the explosive.
20. The fuze of claim 18 , wherein when the sterilization voltage is provided to the exploding foil initiator, the bridge foil is deflagrated without propelling the flyer into the explosive.
21. The fuze of claim 20 , wherein the explosive is not detonated.
22. A method of sterilizing an electronic fuze comprising:
providing an electronic fuze having a firing capacitor and an exploding foil initiator, the exploding foil initiator having an explosive and a maximum acceptable safe stimulus level;
charging the firing capacitor to a predetermined voltage level that is less than the maximum acceptable safe stimulus level;
discharging the firing capacitor across the exploding foil initiator to destroy the exploding foil initiator without causing detonation of the explosive.