ZA200809124B - Blasting exploder - Google Patents

Description

BYE ____~ BLASTING EXPLODER

FIELD OF INVENTION

. The present invention relates to a blasting exploder. } More particularly, the present invention relates to a blasting exploder for use with electric starters, detonators or any other types of initiators which allow synchronised and controlied multi-blasting in a mine. :

BACKGROUND TO INVENTION

Initiators and detonators are used extensively in mining and quarrying. In use, a detonator is arranged in close association with a primer. The initiator or detonator initiates the primer and the primer in turn causes an explosive charge to explode. Three main types of detonators and electric starters are used in industry, namely legacy electric detonators, starters and modern electronic detonators. Initiators for direct ignition of shock tube through an electric spark are also becoming more commonplace.

It is often desirable to set off a series of explosive charges at the same time, which is known as synchronised multi-blasting. However, it is rather difficult to activate a number of detonators or initiators simultaneously (especially when these are widely dispersed through a mine). One method of achieving synchronised multi-blasting is the automatic simultaneous activation of each detonator from a centralised location.

This requires that all the detonators/initiators must be joined to a wire network running through the mine, which is expensive to provide and maintain. Furthermore as the network may become damaged due to blasting, the integrity of the network can be compromised and this can lead to delays in future blasting until the network has been repaired.

It is an object of the invention to suggest a blasting exploder, which will assist in overcoming these problems. . ’ DrG Ref: 674414

In the specification, the term “detonator” is to be understood to refer to any detonator, whether electric or electronic, starter or any other electric - or non-electric initiator that can be used to initiate a blast.

RB Furthermore, a localised control unit having the same function as the } 5 blasting exploder can also be implemented. Thus the term “blasting exploder” is to be understood to be interchangeable with “blasting control unit”. In such case the control unit will be associated with further electronics which will then perform the blast.

SUMMARY OF INVENTION

According to the invention, a blasting exploder adapted to be associated with a detonator includes electronic circuitry being adapted to fire a detonator; activation means for activating the electronic circuitry; a time clock operatively joined to the electronic circuitry; programming means for programming the electronic circuitry with a preselected blasting time; and firing means for firing a detonator when the time clock indicates the preselected blasting time.

The activation means may be adapted to allow activation of the electronic circuitry only during a predetermined time window period prior to the blasting time.

The activation means may be adapted to prevent activation of the electronic circuitry at any time outside the time window period.

The time window period may expire at a set time interval before the blasting time.

The time window period may extend from a time 3 hours before the blasting time up to a time 1 hour before the blasting time.

The time window period may be programmable by an operator. i DrG Ref: 674414

The blasting time may be programmable by an operator.

The time window period and blasting time may be programmable using a } suitable device, such as a smart card or i-button, or any other similar

Bh device.

The blasting time may be pre-programmed into the electronic circuitry during manufacture.

The activation means may include a mechanical key switch or any other secure device.

The time clock may be a real-time clock having a crystal oscillator mechanism.

The blasting exploder may include an indicator light.

The indicator light may be adapted during use to flash intermittently after the electronic circuitry has been activated.

The indicator light may be adapted to flash at 1 second intervals.

The indicator light may be adapted to turn on permanently at least 10 seconds before the blasting time.

The blasting exploder may include a battery being adapted to provide power for firing a detonator and for operating the electronic circuitry and the time clock.

The battery may be trickle charged using either local mains or a low voltage supply in such a manner to reduce cable usage.

The blasting exploder may be adapted to be inoperable if the battery is flat or has insufficient power for firing a detonator and for operating the time clock.

DrG Ref: 674414

The indicator light may be adapted to flash twice and then be deactivated if the battery is flat or has insufficient power and needs replacing.

The blasting exploder may include memory means being adapted to save ' information, such as an identification log, blasting data and date stamps. 5 The saved information may include details of an attempted activation of the electronic circuitry at a time outside of the time window period.

Also according to the invention, a blasting arrangement includes at least one blasting exploder as described herein, the or each blasting exploder being associated with one or more detonators.

The time clocks of each of the blasting exploders in the blasting arrangement may be synchronised.

Each of the blasting exploders in the blasting arrangement may be programmed with a fixed blasting time,

Each blasting exploder in the blasting arrangement may be adapted to be in communication with a master programming unit or computer.

BRIEF DESCRIPTION OF DRAWINGS

The invention will now be described by way of example with reference to the accompanying schematic drawings.

In the drawings there is shown in:

Figure 1: A blasting exploder according to the invention; and

Figure 2: A blasting arrangement according to the invention.

DETAILED DESCRIPTION OF DRAWINGS

Referring to Figure 1 of the drawings, a blasting control unit or exploder in accordance with the invention, generally indicated by reference

Co ~ DrG Ref: 674414

: | ; numeral 10, is shown. The blasting exploder 10 is adapted to be : associated with a detonator, such as an electric detonator or electric : starter, for firing the detonator at a preselected blasting time.

The blasting exploder 10 includes a housing 12 containing electronic circuitry 14 that is operatively joined to a real-time clock 16. The real- time clock 16 is a silicon chip using a crystal oscillator mechanism that is integrally formed with the electronic circuitry 14. The electronic circuitry 14 is further operatively joined to a firing means 18, such as a detonator bridge wire or another device able to set off an initiator. The electronic circuitry 14 is pre-programmed during manufacture with the preselected blasting time at which it is to fire a detonator.

The blasting exploder 10 further includes a mechanical key switch 20 for activating the electronic circuitry 14. The electronic circuitry 14 is able to : be activated only during a predetermined time window period prior to the blasting time. At any other time the electronic circuitry 14 is restricted from being activated. This assists in preventing the blasting exploder 10 from being activated accidentally at a time when it is not intended to be used or when it will be too dangerous to use. The time window period ends at a time interval before the blasting time so that a person activating the electronic circuitry 14 has sufficient time to leave the vicinity of the blasting exploder 10 after the activation.

As an example, the predetermined time window period can extend from a time 3 hours before the preselected blasting time to a time 1 hour before the blasting time, e.g. the time window period for activating the electronic circuitry 14 can be from 3 PM to 5 PM to enable firing of an electrical detonator at a blasting time of 6 PM. These times can be selected as required for each individual mine or location at which the blasting exploder 10 is to be used and pre-programmed into the electronic circuitry 14 during manufacture or by an appointed user. Thus the time . DrG Ref: 674414 window period or its time interval before the blasting time can be shorter for smaller mines or longer for larger mines. : Such pre-programmed time window periods and blasting times enable the

B blasting exploders 10 to be used independently without requiring an operator to program them on-site for each use. There is also no need for any wired or wireless communication between .the separate blasting exploders 10, for resetting them or requiring communication or protocol exchange with a master unit, which consequently saves on operating and infrastructure costs.

Without ever having to be reprogrammed, and provided the blasting exploder 10 was correctly activated / de-activated at the relevant time, the blasting exploders 10 will independently carry on their function of being activated between 3 PM to 5 PM and firing at 6pm every day, or any other selected times as set.

Programming of more than one window per day for multi-shift operations is also possible. :

The blasting exploder 10 further includes a battery 22 providing power for the firing of an electronic detonator and for the operation of the time clock 16. The blasting exploder 10 is inoperable if the battery 22 is flat or has insufficient power to fire the detonator and operate the time clock 16.

An indicator light 24 visible on the outside of the housing 12 flashes intermittently at 1 second intervals when the blasting exploder 10 has been activated. The indicator light 24 flashes twice and then is deactivated if the battery 22 has insufficient power and needs recharging or replacing.

As shown in Figure 2, a synchronised blasting arrangement 30 can be arranged by using a plurality of blasting exploders 10.1 - 10.n together.

In such an arrangement 30, the separate time clocks 16 of the blasting

DrG Ref: 674414

. Co - exploders 10 are synchronised either at the factory or using a hand held programming device so that the detonators are fired simultaneously at the blasting time, within practical tolerance limits of the RTC.

The blasting exploder 10 can be used as an electronic fuse or stay-a-light with an additional safety feature to prevent firing at a particular time when it is unsafe to fire, i.e. outside the time window period.

The user could also use the blasting exploder 10 in a “centralised” blasting system where all the panels are blasted at one time and in which the blasting exploder 10 can only be armed by a user or during a legislation specified period. The blasting exploder 10 can be adapted to communicate with a master programming unit or computer. . The blasting exploder 10 can include memory means (not shown) being adapted to save information, such as diagnostics information (e.g. battery voltage, total number of blasts, when last programmed), identification log (e.g. operator PIN), blasting data (e.g. output voltage, energy) and date stamps (e.g. time and date of activation even if outside of predetermined time frame and of last blast).

DrG Ref: 674414

Claims (27)

® CLAIMS ~~

1. A blasting exploder adapted to be associated with a detonator } including electronic circuitry being adapted to fire a detonator; } } activation means for activating the electronic circuitry; a time clock k operatively joined to the electronic circuitry; programming means for programming the electronic circuitry with a preselected blasting time; and firing means for firing a detonator when the time clock indicates : the preselected blasting time.

2. A blasting exploder as claimed in claim 1, in which the activation means is adapted to allow activation of the electronic circuitry only during a predetermined time window period prior to the blasting time.

3. A blasting exploder as claimed in claim 2, in which the activation means is adapted to prevent activation of the electronic circuitry at any time outside the time window period.

4. A blasting exploder as claimed in claim 2 or 3, in which the time window period expires at a set time interval before the blasting time.

5. A blasting exploder as claimed in claim 4, in which the time window period extends from a time 3 hours before the blasting time up to a time 1 hour before the blasting time.

6. A blasting exploder as claimed in any one of claims 2 to 5, in which the time window period is programmable by an operator.

7. A blasting exploder as claimed in any one of claims 2 to 5, in which the blasting time is programmable by an operator.

8. A blasting exploder as claimed in claim 6 or 7, in which the time window period and blasting time are programmable using a suitable device, such as a smart card or i-button. DrG Ref: 674414

9. A blasting exploder as claimed in any one of the preceding claims, in which the blasting time is pre-programmed into the electronic circuitry during manufacture. a

10. A blasting exploder as claimed in any one of the preceding claims, in } which the activation means includes a mechanical key switch.

11. A blasting exploder as claimed in any one of the preceding claims, in which the time clock is a real-time clock having a crystal oscillator mechanism.

12. A blasting exploder as claimed in any one of the preceding claims, which includes an indicator light.

13. A blasting exploder as claimed in claim 12, in which the indicator light is adapted during use to flash intermittently after the electronic circuitry has been activated.

14. A blasting exploder as claimed in claim 13, in which the indicator light is adapted to flash at 1 second intervals.

15. A blasting exploder as claimed in any one of claims 12 to 14, in which the indicator light is adapted to turn on permanently at least 10 seconds before the blasting time.

16. A blasting exploder as claimed in any one of the preceding claims, which includes a battery being adapted to provide power for firing a detonator and for operating the electronic circuitry and the time clock.

17. A blasting exploder as claimed in claim 16, in which the battery is trickle charged using either iocal mains or a low voltage supply. : DrG Ref: 674414

18. A blasting exploder as claimed in claim 16 or 17, which is adapted to be inoperable if the battery is flat or has insufficient power for firing a detonator and for operating the time clock. N

19. A blasting exploder as claimed in claim 18, in which the indicator light . is adapted to flash twice and then be deactivated if the battery is flat or has insufficient power and needs replacing.

20. A blasting exploder as claimed in any one of the preceding claims, which includes memory means being adapted to save information, such as an identification log, blasting data and date stamps.

21. A blasting exploder as claimed in claim 18, in which the saved information includes details of an attempted activation of the electronic circuitry at a time outside of the time window period.

22. A blasting exploder substantially as hereinbefore described with reference to and as illustrated in the accompanying schematic drawings.

23. A blasting arrangement including at least one blasting exploder as claimed in any one of claims 1 to 22, the or each blasting exploder being associated with one or more detonators.

24. A blasting arrangement as claimed in claim 23, in which the time clocks of the blasting exploders are synchronised.

25. A blasting arrangement as claimed in claim 23 or 24, in which each of the blasting exploders is programmed with a fixed blasting time.

26. A blasting arrangement as claimed in any one of claims 23 to 25, in which each blasting exploder is adapted to be in communication with a master programming unit or computer. : DrG Ref: 674414

27. A blasting arrangement substantially as hereinbefore described with reference to and as illustrated in the accompanying schematic

) drawings. ot Date: 23 October 2008 ) —

John Spicer

DR GERNTHOLTZ INC

Patent Attorneys of Applicant(s)

P O Box 8; Cape Town 8000; South Africa

Union Road; Milnerton 7441; South Africa

Tel: (021) 551 2650

Fax: (021) 551 2960

DrG Ref.: 674414 t:\files\14\674414\674414 spec.doc

DrG Ref: 674414 '