Constant-current, rail-voltage regulated charging electronic detonator
View Patent ↗Regulated charging of an energy storage module in a pyrotechnic device such as a firing capacitor in an electronic detonator, preferably in the form of constant-current charging limited at a “rail voltage,” and optionally limited to a sufficiently low current to provide additional benefits to the pyrotechnic device such as in the case of a short-circuit.
1. A pyrotechnic device comprising:
a) an igniter;
b) a firing energy storage module connected to said igniter; and,
c) a constant-current charging module connected to said firing energy storage module, said constant current charging module within said pyrotechnic device.
2. The pyrotechnic device of claim 1 , wherein said firing energy storage module is connected to said constant current charging module by a switch.
3. The pyrotechnic device of claim 1 , wherein said firing energy storage module is connected to said igniter by a switch.
4. The pyrotechnic device of claim 1 , wherein said firing energy storage module is a firing capacitor.
5. The pyrotechnic device of claim 4 , wherein said pyrotechnic device is an electronic detonator.
6. The pyrotechnic device of claim 5 , further comprising an ASIC containing said constant current charging module.
7. The pyrotechnic device of claim 6 , wherein said electronic detonator is for use in a system of multiple detonators, and said constant current charging module is configured and/or programmed to limit current to said firing capacitor to below an amount that could cause excessive voltage sagging in said system.
8. The pyrotechnic device of claim 7 , wherein said constant current charging module is further configured and/or programmed to limit current to below an amount that could result in inadvertent firing of said igniter.
9. The pyrotechnic device of claim 7 , wherein said constant current charging module is further configured and/or programmed to activate in response to an arming command.
10. A method of charging a pyrotechnic device comprising the following steps:
a) providing at least one pyrotechnic device with an igniter and a firing energy storage module; and
b) charging said firing energy storage module in preparation for firing of said pyrotechnic device, wherein current to said firing energy storage module is limited to a constant current by a constant current module within said pyrotechnic device.
11. The method of claim 10 , further comprising the step of conducting a capacitance check at least partly during step b).
12. The method of claim 10 , further comprising the step of establishing a system including multiple pyrotechnic devices each having an igniter and a firing energy storage module, said system including a master device and a bus connecting said master device to said pyrotechnic devices.
13. The method of claim 12 , wherein said system is an electronic blasting system, said master device is a blasting machine, said pyrotechnic devices are electronic detonators, and said firing energy storage modules are firing capacitors.
14. The method of claim 13 , wherein each of said electronic detonators includes a constant current charging module.
15. The method of claim 14 , further comprising the step of issuing an arming command from said blasting machine, said constant current charging module configured and/or programmed to activate in response to said arming command.
16. The method of claim 15 , wherein said firing capacitor is connected to said constant current charging module by a switch.
17. The method of claim 16 , wherein said firing capacitor is connected to said igniter by a switch.
18. The method of claim 17 , wherein said firing capacitors are charged in a staggered fashion.