Laser activated initiation devices with self-powered event detection and arming logic and false trigger protection for munitions
A laser activated initiation device including: a piezoelectric element; a capacitor; a self-powered acceleration pulse event detection with false trigger protection circuit; a switch reset circuit; and a switching circuit; wherein when the piezoelectric element is subjected to an acceleration pulse the piezoelectric element generates an open-circuit charge profile to charge the capacitor.
1. An electrically initiated inertial switch for detecting an acceleration and a duration of the acceleration for producing a signal when a prescribed acceleration and a prescribed duration of the acceleration occurs, the inertial switch comprising:
a first pin configured to receive a voltage over a duration from an electrical energy generating device that is responsive to an acceleration of the inertial switch;
second and third pins configured to together set a threshold acceleration and a threshold duration of the acceleration of the inertial switch; and
fourth and fifth pins configured to produce an indication when the threshold acceleration and the threshold duration of the acceleration of the inertial switch has occurred.
2. The inertial switch of claim 1 , comprising a Zener diode, wherein the first and second pins are coupled together through the Zener diode to ensure that at least a minimum voltage threshold level occurs prior to a start of the prescribed duration.
3. The inertial switch of claim 2 , comprising first and second resistors, wherein the first resistor couples the first and second pins together through the Zener diode and the second resistor couples the second and third pins together.
4. The inertial switch of claim 3 , comprising a signal switch, wherein the switch control input is coupled to the third pin and the second resistor and is responsive to the inertial switch at least achieving the threshold acceleration and the threshold duration of the acceleration to produce the indication, and wherein the indication is a change in relative states between the fourth and fifth pins.
5. The inertial switch of claim 4 , wherein the relative states between the fourth and fifth pins are conductive and non-conductive states between the fourth and fifth pins.
6. The inertial switch of claim 4 , wherein the fourth and fifth pins operate as a normally-closed switch between the fourth and fifth pins.
7. The inertial switch of claim 4 , wherein the fourth and fifth pins operate as a normally-open switch between the fourth and fifth pins.
8. The inertial switch of claim 4 , comprising a bridge wire coupled to the fourth and fifth pins.
9. The inertial switch of claim 8 , comprising pyrotechnic material positioned in proximity to the bridge wire wherein the bridge wire is configured to ignite the pyrotechnic material in response to the indication.
10. The inertial switch of claim 8 , wherein the signal switch is a first switch and the bridge wire is a first bridge wire, the inertial switch further comprising:
a photovoltaic cell;
a second bridge wire; and
a second switch coupled between the fourth pin and the second bridge wire, where the first bridge wire holds the second switch open and in response to the detection signal, the first bridge wire is configured to open and thereby close the second switch coupling the fourth pin to the second bridge wire.
11. The inertial switch of claim 10 , comprising pyrotechnic material positioned in proximity to the second bridge wire wherein the second bridge wire is configured to ignite the pyrotechnic material in response to coupling the fourth pin to the second bridge wire.
12. The inertial switch of claim 10 , comprising a light source configured to couple light to the photovoltaic cell.
13. The inertial switch of claim 12 , wherein the light source comprises a plurality of light sources configured to couple light to the photovoltaic cell.
14. The inertial switch of claim 10 , comprising a voltage booster circuit configured to boost the output voltage from the photovoltaic cell that is provided to the second bridge wire.
15. The inertial switch of claim 10 , comprising:
an energy generating device coupled to the first pin;
a first energy storage device coupled to the second pin;
a resistive device coupled to the third pin; and
a second energy storage device, wherein the second energy storage device is configured to be charged by the fourth pin to a threshold voltage, whereinafter the charge from the second energy storage device is coupled to the second bridge wire.
16. The inertial switch of claim 15 , comprising a light configured to turn on when the second energy storage device reaches the threshold voltage.
17. The inertial switch of claim 10 , comprising a voltage delay circuit configured to delay providing an output voltage from the closed second switch to the second bridge wire for a predetermined period of time.
18. The inertial switch of claim 17 , comprising:
an energy generating device coupled to the first pin;
a first energy storage device coupled to the second pin;
a resistive device coupled to the third pin; and
a second energy storage device, wherein the second energy storage device is configured to be charged by the fourth pin to a threshold voltage, whereinafter the voltage delay circuit is configured to delay providing the threshold voltage from the second energy storage device to the second bridge wire for a predetermined period of time.
19. The inertial switch of claim 1 , wherein the inertial switch is a programmable electrically initiated inertial igniter.
20. The inertial switch of claim 1 , wherein the inertial switch is a portion of an all-fire detection circuit for an electrically initiated inertial igniter.
21. The inertial switch of claim 1 , wherein the inertial switch is configured as an integrated circuit.
22. The inertial switch of claim 1 , wherein the indication is provided as an all-fire detection signal to an electrically initiated inertial igniter.