Wireless detonator assemblies, corresponding blasting apparatuses, and methods of blasting

• US 7,810,430 B2
• Filed: 11/02/2005
• Issued: 10/12/2010
• Est. Priority Date: 11/02/2004
• Status: Active Grant

• Current Assignee: Orica Explosives Technology Pty Limited (Orica Limited)
• Original Assignee: Orica Explosives Technology Pty Limited (Orica Limited)
• Inventors: Stewart, Ronald F., Bampfield, Howard A., Chan, Sek Kwan
• Primary Examiner(s): Carone; Michael
• Assistant Examiner(s): Weber; Jonathan C
• Application Number:
  US11/718,027
• Publication Number:
  US 20080307993A1
• Time in Patent Office: 1,805 Days
• Field of Search: 102/206, 102/301, 102/305, 102/308, 102/310, 102/311, 361/251, 361/256, 361/257, 320/108
• US Class Current: 102/206
• CPC Class Codes: F42B 3/113 activated by optical means, e.g. laser, flashlight
• CPC Class Codes: F42B 3/121 Initiators with incorporated integrated circuit
• CPC Class Codes: F42C 15/42 from a remote location, e.g. for controlled mines or mine fields
• CPC Class Codes: F42D 1/045 Arrangements for electric ignition dynamo-electric generators H02K

Abstract

A wireless or partially wireless detonator assembly (10) and corresponding blasting apparatus, that may be “powered Up” by a remote source of power (13) that is entirely distinct from the energy used for general command signal communications (16). In one embodiment, the detonator assembly (10) may include an active power source (25) with sufficient power for communications, but insufficient power to cause intentional or inadvertent actuation of the detonator (10).

Claims

1. A detonator assembly for use in connection with at least one blasting machine that transmits at least one wireless command signal via a first medium, the detonator assembly comprising:

a base charge;

a command signal receiving and processing means for wirelessly receiving and processing said at least one command signal from said at least one blasting machine;

an active power source to power said command signal receiving and processing means;

a power receiver for wirelessly receiving via a second medium power transmitted by a power emitter;

converting means for converting said power received from the power receiver to electrical power;

a passive power source in electrical connection with the converting means, the passive power source capable of storing said electrical power derived from said converting moans thereby to charge the detonator; and

a firing circuit in connection with said base charge, for selectively receiving said electrical power stored in said passive power source, said active power source generating a power insufficient to activate said firing circuit and actuate said base charge, wherein receipt of a command signal to FIRE by said command signal receiving means causes release of said electrical power from said passive power source into said firing circuit thereby to actuate said base charge.

2. The detonator assembly of claim 1, wherein said at least one command signal comprises:

radio waves, electromagnetic energy, acoustic energy, or involves electromagnetic induction.

3. The detonator assembly of claim 2, wherein the radio waves comprise VLF, ULF or ELF transmission.

4. The detonator assembly of claim 3, wherein the radiowaves have a frequency of from 100 to 2000 Hz.

5. The detonator assembly of claim 4, wherein the radio waves have a frequency of from 200 to 1200 Hz.

6. The detonator assembly of claim 1, wherein the power from the power emitter comprises:

radio waves, electromagnetic energy, acoustic energy or involves electromagnetic induction.

7. The detonator assembly of claim 6, wherein the radio waves comprise VLF, ULF or ELF transmission.

8. The detonator assembly of claim 1, wherein the command signal receiving means and the power receiver comprises an electromagnetic energy receiving means, said command signal comprising electromagnetic energy of a first wavelength, said power emitted from said power emitter comprising electromagnetic energy of a second wavelength, said detonator assembly further comprising:

differentiating means in association with said electromagnetic energy receiving means for differentiating said electromagnetic energy of a first wavelength from said electromagnetic energy of a second wavelength, said electromagnetic energy of a first wavelength being received and processed by said command signal receiving and processing means, said electromagnetic energy of a second wavelength being converted by said converting means into said electrical power.

9. The detonator assembly of claim 8, wherein the electromagnetic energy of a first wavelength is received from a plurality of electromagnetic power emitters, each targeting the detonator assembly.

10. The detonator assembly of claim 8, wherein the electromagnetic energy of a second wavelength is received from a plurality of electromagnetic power emitters, each targeting the detonator assembly.

11. The detonator assembly of claim 8, wherein the differentiating means comprises one or more optical filters.

12. The detonator assembly of claim 8, wherein the electromagnetic energy of a first wavelength has a longer wavelength than the electromagnetic energy of a second wavelength.

13. The detonator assembly of claim 8, wherein the electromagnetic energy of a first wavelength is derived from at least one red laser.

14. The detonator assembly of claim 8, wherein the electromagnetic energy of a second wavelength is derived from at least one blue laser.

15. The detonator assembly of claim 1, wherein the command signal receiving and processing means comprises radio wave receiving means, said at least one command signal comprising radio wave transmission, and wherein said power receiver comprises electromagnetic energy receiving means, said emitted power comprising electromagnetic energy other than radio waves.

16. The detonator assembly of claim 1, wherein the command signal receiving and processing means comprises electromagnetic energy receiving means, at least one command signal comprising electromagnetic, energy, and wherein said power receiver comprises radio wave receiving means, said emitted power comprising radio waves.

17. The detonator assembly of claim 1, wherein the command receiving means comprises a first light energy receiving means, said command signals comprising light energy of a first wavelength, and wherein said power receiving comprises a second light energy receiving means, said emitted power comprising light energy of a second wavelength.

18. The detonator assembly of claim 17, wherein the light energy of a first wavelength is derived from at least one red laser, and the light energy of a second wavelength is derived from at least one blue laser.

19. The detonator assembly of claim 1, wherein said power receiver comprises an electromagnetic induction energy receiving means, said emitted power comprising electrical energy transmitted to said detonator assembly at least in part through electromagnetic induction.

20. The detonator assembly of claim 19, wherein the electromagnetic induction energy receiving means comprises at least one magnetic coupling device each in electromagnetic induction action relationship with at least one current-carrying conductive wire selectively carrying current from said power emitter.

21. The detonator assembly of claim 20, wherein each magnetic coupling device is a toroidal transformer, optionally comprising ferrite.

22. The detonator assembly of claim 21 wherein the light energy received by each light capture device is derived from a filament bulb, laser, laser diode, or LED.

23. The detonator assembly claim 22, wherein the light energy is derived from a laser.

24. The detonator assembly of claim 1, wherein command signal receiving means and/or the power receiver receives electromagnetic energy and comprises an electromagnetic energy receiving means.

25. The detonator assembly of claim 1, wherein said passive power source is selectee from the group consisting of:

a capacitor, a diode, a rechargeable battery, fuel cell, an air cell such as a hearing aid battery, a micro-nuclear power source, and an activatable battery.

26. The detonator assembly of claim 1, further comprising a firing switch located between said passive power source and said firing circuit, said firing switch switching from an OFF position to an ON position upon receipt of a command signal to FIRE by said command signal receiving means, thereby establishing electrical connection between said passive power source and said firing circuit, to cause discharge of electrical power stored in said passive power source into said firing circuit, thereby to actuate said base charge.

27. The detonator assembly of claim 1. wherein the command signal receiving and processing means and/or the power receiver receives light energy and comprises a light capture device and optionally an optical cable for transferring light received by the light capture device to the converting means.

28. The detonator assembly of claim 27, wherein the light capture device can be positioned above ground to receive said light energy, said optical cable transferring said light energy into the ground to said converting means.

29. The detonator assembly of claim 1. wherein the converting means comprises a photovoltaic cell, a photodiode, or a phototransistor.

30. The detonator assembly of claim 1, wherein each command signal is selected from the group consisting of:

ARM signals, DISARM signals, FIRE signals, detonator delay times, and detonator firing codes.

31. me detonator assembly of claim 1, further comprising signal transmission means for generating and transmitting at least one communication signal for receipt by said at least one blast machine.

32. The detonator assembly of claim 31, wherein each communication signal comprises detonator delay times, detonator firing codes, or detonator status information.

33. A blasting apparatus comprising:

at least one blasting machine capable of transmitting, command signals to associated detonators via wireless communications via a first medium;

at least one explosive charge;

at leas one detonator assembly of claim 1 associated with each explosive charge and in signal communication with said at least one blasting machine;

at least one power emitter for transmitting power via a second medium to each detonator assembly for receipt thereby in a suitable form to charge each detonator assembly for firing in response to a FIRE command signal from said at least one blasting machine; and

optionally a central command station for controlling said at least one blasting machine.

34. The blasting apparatus of claim 33, wherein said at least one command signal comprises:

radio signals, electromagnetic energy such as light energy, microwave energy, infrared, acoustic energy or involves electromagnetic induction.

35. The blasting apparatus of claim 33, wherein the emitted power comprises;

radio signals, electromagnetic energy such as light energy, microwave energy, infrared, acoustic energy, or involves electromagnetic induction.

36. A method of blasting at a blast site, the method comprising the steps of;

providing a blasting apparatus of claim 33;

placing a plurality of explosive charges at the blast site;

associating each detonator assembly with an explosive charge such that actuation of each detonator assembly will cause actuation of each associated explosive charge;

targeting said power emitted from said power emitter to said at least one detonator assembly to cause each detonator assembly to receive said emitted power and convert said emitted power to electrical energy thereby to charge each detonator assembly for firing; and

transmitting at least one command signal from said at least one blasting machine to cause each detonator assembly to discharge said electrical power into said firing circuit, thereby causing actuation of each base charge.

37. The method of claim 36, wherein said at least one command signal further comprises delay times for each detonator assembly, thereby to cause the detonator assemblies to fire in a specific timing pattern.

38. The method of claim 36, wherein each detonator assembly comprises a stored firing code, and said at least one command signal further comprise firing codes, each detonator assembly firing only if a stored firing code and a firing code from a command signal correspond.

39. The method of claim 36, wherein said at least one command signal and/or the emitted power comprises light energy.

40. The method of claim 36, further comprising the step of:

verifying whether each detonator assembly is sufficiently charged to actuate the base charge, and if not then repeating at least the step of targeting.

41. Use of the blasting apparatus of claim 33, in a mining operation.

42. Use of claim 41, wherein the mining operation is an automated mining operation involving robotic placement and establishment of explosive charges and/or detonator assemblies at the blast site.

43. Use of the detonator assembly of claim 1, in a mining operation.

44. Use of claim 43, wherein the mining operation is an automated mining operation involving robotic placement and establishment of explosive charges and/or detonator assemblies at the blast site.