Method of controlling detonators fitted with integrated delay electronic ignition modules, encoded firing control and encoded ignition module assembly for implementation purposes

• US 5,520,114 A
• Filed: 09/13/1993
• Issued: 05/28/1996
• Est. Priority Date: 09/17/1992
• Status: Expired due to Term

• Current Assignee: Davey Bickford
• Original Assignee: Davey Bickford
• Inventors: Harle, Denis, Guimard, Andre, Pathe, Claude
• Primary Examiner(s): Lobo, Ian J.
• Application Number:
  US08/120,178
• Time in Patent Office: 988 Days
• Field of Search: 102/200, 102/202.5, 102/206, 102/215, 102/217, 361/247, 361/251
• US Class Current: 102/215
• CPC Class Codes: F42D 1/055 specially adapted for firing multiple charges with a time delay

Abstract

Method according to which, the programming unit (18) transmits, after completion of the programming of the ignition modules, the delay times also programmed to the firing control unit (17). The firing control unit (17) can interrogate simultaneously the ignition modules (15) which send back the information requested to it. The encoded firing control assembly and the encoded ignition modules enable to implement the process.

Claims

1. Method of controlling detonators fitted with integrated delay electronic ignition modules (15), each detonator having an ignition module and an ignitor, each ignition module (15) comprising a first reservoir capacitor (29) designed, after loading, to discharge in an associated ignitor (13) in order to generate a firing electrical pulse, a time base as well as logic unit (303) comprising a second reservoir capacitor (44) designed to supply the necessary energy to the rest of the logic unit, if line voltage is cut off, and a memory in order to store in said ignition module (15) a delay time for the explosion of said detonator, during a firing sequence, said ignition modules being able to communicated with a firing control unit (17) designed to transmit to said ignition modules an order to load the first reservoir capacitor (29) as well as a firing order and to receive from said modules, data about their conditions, said method comprising:

before a firing sequence, storing individual ignition module delay times in the ignition modules via a programming unit (18), wherein, once the ignition modules have been programmed, the delay times programmed are stored in the firing control unit (17) via the programming unit (18), the firing control unit (17) can interrogate the ignition modules simultaneously, said ignition modules send the data requested back to said firing control unit (17), and all steps for said method are executed by signals exhibiting an intensity substantially less than a threshold intensity necessary to operate the ignitor (13).

2. Method according to claim 1, further comprising during programming, measuring the time base of every ignition module.

3. Method according to claim 1, wherein the delay times are different for every module (15) and the modules send the information requested back after a feedback time with respect to the delay time stored in each of them, said firing control unit (17) opening reception gate time corresponding to the feedback time.

4. Method according to claim 1, wherein the ignition modules send back to the firing control unit (17) the information requested, according to a time sequence corresponding to the firing time sequence.

5. Method according to claim 1, wherein the firing control unit (17) interrogates simultaneously the ignition modules via an on-line test order, before a loading phase and a firing phase and the ignition modules send back to the firing control unit (17) global information about their condition.

6. Encoded firing control assembly comprising a firing control unit (17), plural ignition modules (15) with intergrated electronic delay for firing a detonator, each module being connected electrically on-line to said firing control unit (17), a two-wire line between the firing control unit (17) and each ignition module (15) for supplying power to said ignition modules, as well as for communications between said firing control unit (17) and said ignition modules (15) and an independent programming unit (18) connectible to said firing control unit and said plural ignition modules.

7. Assembly according to claim 6, wherein each of the ignition modules comprise means enabling them to send to the firing control unit (17) information in the form of overconsumption of line current, whereas the firing control unit (17) is fitted with detection means of a line current overconsumption with respect to the average consumption of the ignition modules.

8. Encoded firing control assembly according to claim 6, wherein every ignition module comprises a time base formed by an RC circuit.

9. Assembly according to claim 6, wherein the programming unit (18) is able to communicate separately with every ignition module (15) to store the explosion delay times in said ignition modules, and the firing control unit (17) is able to monitor the firing phases during a firing sequence.

10. Assembly according to claim 9, wherein the programming unit (18) is fitted with means for the storing of all the delay times which have been programmed and are transferred separately by the programming unit to every ignition module, and the firing control unit (17) and the programming unit (18) are able to communicate in order to enable transfer, before a firing sequence, of all the delay times programmed.

11. Assembly according to claim 6 wherein the firing control unit (17) and programming (18) unit are fitted with encoding means designed to limit access to only authorized people and with means for internal mutual recognition before transfer of the delay times programmed of the programming unit (18) to the control unit (17).

12. Detonator ignition module for a detonator having a pyrotechnic charge, said module comprising a supply circuit, a communication interface, a management circuit of the pyrotechnic charge, said management circuit including a reservoir capacitor (29) designed, after loading, to discharge in an ignitor (13) of said detonator, a logic unit (303) for the management of the module, a supply source of line voltage mounted in series with the reservoir capacitor (29), a first switching transistor (21) to control the charge of said reservoir capacitor (29) and a resistor (27) linked by the one pin which is not connected directly to the reservoir capacitor (29) to a second switching transistor (22) to discharge said a reservoir capacitor (29) to ground.

13. Module according to claim 12, wherein the impedance between the supply of the management circuit of the pyrotechnic charge and the ignitor (13) is high enough so that the current generated by the line voltage in the ignitor (13) is, whatever the condition of the first and second switching transistors, less than the value of the operating limit current of said ignitor (13).

14. Module according to claim 13, wherein the value of said resistor (27) of the reservoir capacitor is high enough so that the current generated by said supply in the ignitor (13) is, whatever the condition of the first and second switching transistors, less than the value of the operating limit current of said ignitor.

15. An integrated delay electronic ignition module for controlling a detonator fitted with a pyrotechnic charge, said module comprising a supply circuit designed to be connected to a supply source having line voltage, a communication interface designed to establish a bi-directional communication path between the ignition module and one of a firing console and a programming unit, and a management circuit of the pyrotechnic charge;

said management circuit including a reservoir capacitor designed, after loading, to discharge in an ignitor of its detonator in order to generate a firing electrical pulse, a time base as well as a logic unit fitted with a memory in order to store in said ignition module a delay time for the explosion of said detonator, during a firing sequence, a first switching transistor to control the charge of said reservoir capacitor from the supply source, a resistor linked by one pin not connected directly to the reservoir capacitor to a second switching transistor to discharge said reservoir capacitor to ground, and a third switching transistor which is a firing device of the pyrotechnic charge, said resistor being high enough value so that the current generated by said supply source in the ignitor is, whatever the condition of said first, second, and third switching transistors, less than a value of the operating limit current of said ignitor.

16. Module according to claim 15, wherein the impedance between the supply of the management circuit of the pyrotechnic charge and the ignitor is high enough so that the current generated by the supply source in the ignitor is, whatever the condition of said first, second and third switching transistors, less that the value of said operating limit current of said ignitor.