Method of communication at a blast site, and corresponding blasting apparatus

• US 7,848,078 B2
• Filed: 02/15/2008
• Issued: 12/07/2010
• Est. Priority Date: 02/16/2007
• Status: Active Grant

• Current Assignee: Orica Explosives Technology Pty Limited (Orica Limited)
• Original Assignee: Orica Explosives Technology Pty Limited (Orica Limited)
• Inventors: Hummel, Dirk, Lownds, Charles Michael
• Primary Examiner(s): Jackson; Stephen W
• Application Number:
  US12/031,956
• Publication Number:
  US 20100275799A1
• Time in Patent Office: 1,026 Days
• Field of Search: 361/247
• US Class Current: 361/247
• CPC Class Codes: F42C 15/42 from a remote location, e.g. for controlled mines or mine fields
• CPC Class Codes: F42D 1/055 specially adapted for firing multiple charges with a time delay
• CPC Class Codes: F42D 3/04 for rock blasting

Abstract

Blasting operations for mining frequently involve a large number of detonators for a single blasting event. An important step in the execution of a blast is to perform a roll-call to check that all detonator assemblies placed at the blast site are in communication with a blasting machine, and forming operative components of the blasting apparatus. Disclosed herein are blasting apparatuses and methods of blasting that streamline this roll-call step, thereby reducing time consumed in the blasting process.

Claims

1. A blasting apparatus comprising:

(1) at least one blasting machine for transmitting at least one command signal to at least two associated detonator assemblies, at least including an all-acknowledge command signal for receipt by said at least two detonator assemblies;

(2) at least two detonator assemblies, each detonator assembly comprising;

(i) a detonator including a base charge;

(ii) a memory for storing an anti-collision response time;

(iii) a clock for counting down the anti-collision response time upon receipt from said at least one blasting machine of said all-acknowledge command signal; and

(iv) a transmitter for transmitting an acknowledge signal in response to said all-acknowledge command signal, upon expiry of said anti-collision response time;

and

(3) at least one receiver, optionally integrated into said at least one blasting machine, for receiving said acknowledge signals from said detonator assemblies, and differentiating each acknowledge signal from at least one other acknowledge signal in accordance with its time of receipt, thereby to verify communication with each detonator assembly of said blasting apparatus.

2. The blasting apparatus of claim 1, wherein said at least one receiver processes and differentiates incoming acknowledge signals, and if required determines from which detonator assembly each acknowledge signal is derived, by way of a time of receipt of each acknowledge signal relative to other acknowledge signals, or relative to a time zero.

3. The blasting apparatus of claim 2, wherein each detonator assembly is programmed with an anti-collision response time that is different from anti-collision response times programmed into all other detonator assemblies in the blasting apparatus, so that the at least one receiver differentiates each acknowledge signal from all other acknowledge signals in accordance with its time of receipt.

4. The blasting apparatus of claim 1, wherein the blasting apparatus further comprises a portable programming device for programming each detonator assembly with its anti-collision response time via short-range communication, after placement of each detonator assembly at the blast site.

5. The blasting apparatus of claim 4, wherein the portable programming device records blast site information including an identification for each detonator assembly, an anti-collision response time for each detonator assembly, and optionally a delay time for each detonator assembly.

6. The blasting apparatus of claim 5, wherein the logger downloads the blast site information to said at least one blasting machine, and following transmission by said at least one blasting machine of said all-acknowledge command signal, and subsequent receipt by said blasting machine of said acknowledge signals from said at least two detonator assemblies, said at least one blasting machine associating each acknowledge signal with each detonator assembly in accordance with said blast site information.

7. The blasting apparatus of claim 4, wherein the portable programming device assigns a unique response number to each detonator assembly, indicative of a sequence in which the detonator assemblies respond upon receipt of an all-acknowledge command, each anti-collision response time being calculated by each detonator assembly based upon its assigned response number.

8. The blasting apparatus of claim 1, wherein the anti-collision response times of the detonator assemblies include a series of anti-collision response times substantially equally temporally spaced, such that transmission by said at least one blasting machine of an all-acknowledge command signal to said detonator assemblies causes transmission by said detonator assemblies of a regularly temporally spaced sequence of said acknowledge signals for receipt by said receiver.

9. The blasting apparatus of claim 8, wherein the acknowledge signals are received by said at least one receiver from about 0.1 to 100 ms apart.

10. The blasting apparatus of claim 1, wherein any detonator assembly that has not been suitably programmed with an anti-collision response time prior to transmission of said all-acknowledge command signal, is pre-programmed to respond to said all-acknowledge command signal by transmission of a warning signal to warn the receiver or a blast operator that the detonator assembly has not been suitably programmed.

11. The blasting apparatus of claim 10, wherein each warning signal has a content similar or identical to that of an acknowledge signal, but is transmitted at a specific time following receipt of the all-acknowledge command signal that is different to a time of transmission of any of the acknowledge signals and optionally different to a time of transmission of any other warning signal, such that the receiver can differentiate each warning signal from the acknowledge signals.

12. The blasting apparatus of claim 10, wherein the warning signal includes data comprising an identification for the detonator.

13. The blasting apparatus of claim 7, wherein the receiver is programmed to expect acknowledge signals of a predetermined number or in a predetermined sequence from said detonator assemblies, such that failure of a detonator assembly to transmit an acknowledge signal is detected by said receiver due to its absence from the predetermined number or predetermined sequence of acknowledge signals.

14. A detonator assembly for use in connection with the blasting apparatus of claim 1, the detonator assembly comprising:

(i) a detonator including a base charge;

(ii) a dedicated memory for storing an anti-collision response time;

(iii) a clock for counting down an anti-collision response time when stored in the memory upon receipt from a blasting machine of an all-acknowledge command signal; and

(iv) a transmitter for transmitting an acknowledge signal in response to said all-acknowledge command signal, upon expiry of said anti-collision response time.

28. Use of a blasting apparatus of claim 1, to verify communication with components of the blasting apparatus.

15. A method for checking that at least two detonator assemblies form operative components of a blasting apparatus at a blast site, the method comprising the steps of:

(1) programming each detonator assembly with an anti-collision response time;

(2) transmitting from at least one blasting machine an all-acknowledge command signal for receipt by the detonator assemblies, to cause each detonator assembly to count-down its programmed anti-collision response time;

(3) transmitting from each detonator assembly, upon completion of count-down of its programmed anti-collision response time, an acknowledge signal to at least one receiver optionally forming part of said at least one blasting machine, a time of receipt by said at least one receiver of each acknowledge signal occurring at a time different to a time of receipt of at least one other acknowledge signal, thereby permitting differentiation of said acknowledge signals by said receiver, and providing confirmation that each detonator assembly forms a operative component of the blasting apparatus.

16. The method of claim 15, wherein each anti-collision response time differs from every other anti-collision response time, and a time of receipt by said at least one receiver of each acknowledge signal occurs at a time different to a time of receipt of every other acknowledge signal.

17. The method of claim 15, wherein in step (3) the at least one receiver processes and differentiates incoming acknowledge signals, and if required determines a detonator assembly from which each acknowledge signal is derived, by way of a time of receipt of each acknowledge signal relative to other acknowledge signals, or relative to a time zero.

18. The method of claim 15, wherein step (1) comprises programming each detonator assembly with its anti-collision response time via short-range communication, after placement of each detonator assembly at the blast site using a portable programming device.

19. The method of claim 18, wherein the portable programming device records blast site information including an identification for each detonator assembly, an anti-collision response time for each detonator assembly, and optionally a delay time for each detonator assembly.

20. The method of claim 19, wherein between steps (1) and (3) the method further comprises the step of:

downloading the blast site information from the portable programming device into said at least one blasting machine, so that following transmission by said at least one blasting machine of said all-acknowledge command signal, and subsequent receipt by said blasting machine of said acknowledge signals from said at least two detonator assemblies, said at least one blasting machine associates each acknowledge signal with each detonator assembly in accordance with said blast site information.

21. The method of claim 18, wherein in step (1) the portable programming device assigns a unique response number to each detonator assembly, indicative of a sequence in which the detonator assemblies respond upon receipt in step (2) of an all-acknowledge command signal, each anti-collision response time being calculated by each detonator assembly based upon its assigned response number.

22. The method of claim 15, wherein the anti-collision response times of the detonator assemblies include a series of anti-collision response times substantially equally temporally spaced, such that transmission by said at least one blasting machine of an all-acknowledge command signal to said detonator assemblies causes transmission by said detonator assemblies in step (3) of a regularly temporally spaced sequence of said acknowledge signals for receipt by said at least one receiver.

23. The method of claim 22, wherein the acknowledge signals are received by said receiver from about 0.1 to 100 ms apart.

24. The method of claim 18, wherein any detonator assembly that has not been suitably programmed by the portable programming device in step (1), is pre-programmed to respond to said all-acknowledge command signal in step (3) by transmission of a warning signal to warn the receiver or a blast operator that the detonator assembly has not been visited by the portable programming device.

25. The method of claim 24, wherein each warning signal has a content similar or identical to that of an acknowledge signal, but is transmitted at a specific time following receipt of the all-acknowledge command signal that is different to a time of transmission of any of the acknowledge signals and optionally different to a time of transmission of every other warning signal, such that the receiver can differentiate each warning signal from the acknowledge signals.

26. The method of claim 24, wherein each warning signal includes data comprising a factory encoded identification for the detonator.

27. The method of claim 22, wherein in step (3) the receiver is programmed to expect acknowledge signals of a predetermined number or in a predetermined sequence from said detonator assemblies, such that failure of a detonator assembly to transmit an acknowledge signal is detected by said receiver due to its absence from the predetermined number or predetermined sequence of acknowledge signals.