WO2017059463A1

WO2017059463A1 - Detonator connector

Info

Publication number: WO2017059463A1
Application number: PCT/ZA2016/050037
Authority: WO
Inventors: Andre Louis Koekemoer; Johannes Petrus Kruger; Christo Peltz
Original assignee: Detnet South Africa (Pty) Ltd
Priority date: 2015-09-28
Filing date: 2016-09-27
Publication date: 2017-04-06
Also published as: AR106177A1; ZA201802046B

Abstract

A detonator connector for use in a blasting system which includes a communication structure for use in communicating with a blasting appliance, formations for engagement with at least a part of a trunk line which, in use, extends to at least one detonator, and an element which, in response to a first signal received via the communication structure from the blasting appliance, emits a second signal, via the trunk line to the detonator.

Description

DETONATOR CONNECTOR

BACKGROUND OF THE INVENTION

[0001] This invention relates to a connector for use in a blasting system which includes one or more detonators. [0002] A detonator can be initiated in different ways. In one approach an electrical signal propagated on conductive wires is used to deliver energy to a detonator and that energy is used to fire the detonator when needed. In a different technique an electrical signal is used in a control mode to cause the release of energy stored in a suitable device (e.g. a battery) on the detonator, and that energy release is used for firing purposes. [0003] A shock tube can also be used for firing a detonator. However, a shock tube does not have a capability to transfer control or communication signals between a blasting machine and the detonator, and some additional arrangement is required for this purpose.

[0004] An object of the present intention is to provide a detonator connector which can be adapted for use with different communication and firing arrangements in a detonator system . SUMMARY OF THE I NVENTION

[0005] The invention provides a connector for use in a blasting system which includes one or more detonators, the connector including a body and, in or on the body, a communication structure for use in communicating directly or indirectly with a blasting appliance, formations for engagement with at least a part of a trunk line which, in use, extends to at least one detonator, and an element which, in response to a first signal received via the communication structure from the blasting appliance, emits a second signal, via the trunk line to the detonator.

[0006] The blasting appliance may be a blasting machine, a tagger or any similar mechanism . Communication via the communication structure may be done wirelessly for example using Bluetooth or a similar near-zone or field communication facility.

[0007] The second signal may be emitted at any suitable frequency e.g. in the infrared range. Preferably the emitted second signal is in the visible spectrum. The element may be a light- emitting device such as a light-emitting diode. The aspects are exemplary only and non- limiting.

[0008] When the connector is configured to work in the visible spectrum the trunk line may include a fibre-optic cable and the emitted second signal may be directed to an end of the fibre-optic cable located in or on the body.

[0009] Communication between the blasting appliance e.g. a tagger or a blasting machine and the communication structure may be effected using an interconnecting cable or conductor which transfers an electrical signal from the blasting appliance to the communication structure: or wirelessly i.e. without an intervening physical link between the communication structure and the blasting appliance using, say, Bluetooth techniques. The nature of the communication structure then varies accordingly. I n one form of the invention a bus or harness connects the blasting appliance to the communication structure. I n this case the communication structure may then include contacts for electrical engagement with conductors in the bus. These contacts may be provided in the form of insulation displacement contacts. The light-emitting diode referred to may be connected to the conductors directly or via suitable connectors.

[0010] The connector may be configured to work in a reverse mode, ie. light from a fibre-optic cable in the trunk line, impinging on the element, may initiate the generation of a communication signal which is directed to the blasting appliance.

[001 1] The trunk line, in one embodiment of the invention, may include at least one fibre-optic cable and a shock tube. The fibre-optic cable may be used for communication and control purposes between the blasting appliance and the detonator, and the shock tube may be used for firing the detonator.

[0012] The body of the connector may include at least first and second parts which are relatively movable between an open position at which the communication structure and the formations are accessible and a closed position at which the communication structure and formations are shrouded or covered. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] The invention is further described by way of example with reference to the accompanying drawings in which:

Figure 1 shows the use of a connector according to the invention in a detonating system, and Figure 2 shows the connector of Figure 1 , on a large scale. DESCRIPTION OF PREFERRED EMBODIMENT

[0014] Figure 1 of the accompanying drawings illustrates a connector 10, according to the invention, which is included in a blasting system 12. Figure 2 shows the connector 10 on a larger scale [0015] The blasting system 12 incorporates a bus 14, a blasting appliance 16, e.g. a blasting machine and a plurality of detonators 18, only one of which is illustrated. The detonator is located in a blast hole 20 which contains explosive 22, as is known in the art. The detonator 18 is connected to a trunk line 24 and the trunk line is connected to the bus 14 by means of the connector 10. Other detonators (not shown) in the system are similarly connected via the bus 14 and respective trunk lines to the blasting appliance 16. The detonators are in any appropriate configuration - an aspect which is not important to an understanding of the present invention.

[0016] In this embodiment of the invention the bus 14 includes a pair of insulated electrical conductors 26 and 28 respectively which are electrically connected to the blasting appliance 16.

[0017] The trunk line 24 includes two components, viz. a first component which comprises a fibre-optic cable 30, and a second component which comprises a shock tube 32. The components 30 and 32 can be integrally formed, ie. physically linked together (as shown), or can be separately provided. [0018] The shock tube 32 is coupled by any appropriate means, not shown, to the blasting appliance 16 or to any other suitable firing initiator.

[0019] The connector 10 has a body 38 which includes a base 40 and a lid 42 which is hingedly connected along a line 44 to the base 40. Positioned in the base 40 are two terminals in the form of insulation displacement contacts 46 and 48 respectively. The lid 42 can be opened (as shown) so that the conductor 26 can be electrically coupled to the contact 46, and so that the conductor 28 can be electrically coupled to the contact 48.

[0020] A light-emitting diode 50, which is mounted to the base 40, has two leads 52 and 54 which, under factory conditions, are electrically connected to the contacts 46 and 48 respectively. A light-emitting surface 60 of the light-emitting diode 50 is positioned to face towards engagement formations 62 on the base 40. The fibre-optic cable 30 can be coupled to these formations 62, under field conditions, so that an exposed end 66 of the fibre-optic cable 30, at the base 40, directly opposes the light-emitting surface 60 of the light-emitting diode 50. [0021] If an electrical signal, which could be a communication or a control signal, suitably configured, is impressed on the conductors 26 and 28 by the blasting appliance 16, then a voltage pulse is applied to the leads 52 and 54 and the light-emitting diode 50 is caused to emit light. The emitted light is in a suitably encoded form. In this way a control or communication signal which is emitted by the light-emitting diode 50 is caused to impinge directly on the exposed end 66 of the fibre-optic cable. The signal, captured by the fibre-optic cable 30, is then transferred to the detonator 1 8 where it is employed, in an appropriate manner, for control or communication purposes.

[0022] Typically the blasting appliance is a tagger, or a suitable device which wirelessly, e.g. by using Bluetooth techniques, communicates with the connector. [0023] If the detonator 18 has an energy source, e.g. in the form of a battery 68, then that source can be used to power a light-emitting device, e.g. an LED 70, in the detonator 18. A communication or control signal can then be transmitted via the fibre-optic cable 30 to the light- emitting diode 50 in the connector 10. The reception of the light signal by the diode 50 causes an electrical pulse to appear at the leads 52 and 54 and this is detected by circuitry at the blasting appliance 16.

[0024] The signal which is impressed on the bus 14 is encoded with an identity, e.g. an address of a targeted detonator which can thus be uniquely addressed. This characteristic is necessary for detonator programming purposes.

[0025] The firing of the detonator 18 can be achieved by means of a signal which is generated by ignition of the shock tube 32 and which is then guided to the detonator 18 by the shock tube 32.

[0026] The light-emitting diode 50 could be mounted to a printed circuit board (PCB), which is located within or on the connector body 38. The use of a PCB facilitates the incorporation of other components, which could be used for control, communication, or signal processing or conditioning purposes, in the connector 10. For example, as shown in an inset drawing in Figure 1 , a PCB 74 could be mounted to the connector body 38. The PCB 74 has, fixed to it, a battery 76 and a circuit 78 which, responsive to a signal from the blasting appliance 16, powers the LED 50 which can then, for example, relay a signal to the detonator 18. The circuit 78 could, in one embodiment, include a transmitter/receiver unit 80 which is responsive to a signal, originated in the blasting appliance 16, which is transmitted at a radio frequency, for example through the use of a Bluetooth or other near-field communication system. A corresponding signal at an optical frequency is then transmitted by the LED 50 via the fibre- optic cable 30 to the detonator 18. In the return direction an optical signal from the detonator travels via the fibre-optic cable 30 to the unit 80 v/hich is on surface and a radio signal is then transmitted from the unit 80 to the blasting appliance or to another appropriate device.

Claims

1 . A connector for use in a blasting system which includes one or more detonators, the connector including a body and, in or on the body, a communication structure for use in communicating with a blasting appliance, formations for engagement with at least a part of a trunk line which, in use, extends to at least one detonator, and an element which, in response to a first signal received via the communication structure from the blasting appliance, emits a second signal, via the trunk line to the detonator.

2. A connector according to claim 1 wherein, in use, a bus connects the blasting appliance to the communication structure and wherein the communication structure includes contacts for electrical engagement with conductors in the bus.

3. A connector according to claim 2 wherein the element is a light-emitting device which is connected to the contacts and which emits the second signal in the visible spectrum.

4. A connector according to claim 1 wherein the element is a light-emitting device and the first signal is a radio signal, and wherein the communication structure includes a communication unit which, in response to receiving the radio signal, causes the light emitting device to emit the second signal in the visible spectrum.

5. A connector according to claim 4 wherein the blasting appliance is a tagger.

6. A connector according to any one of claims 1 to 5 wherein the formations are engageable with a fibre-optic cable which is included in the trunk line.

7. A connector according to any one of claims 1 to 6 wherein the trunk line includes a shock tube.

8. A blasting system which includes a blasting appliance, a plurality of detonators which are located in respective boreholes, and, for each detonator, a respective connector which is according to any one of claims 1 to 6 and a respective trunk line which extends, and which is connected, to the detonator, and wherein the trunk line includes a shock tube, and a fibre-optic cable which is engaged with the formations on the body of the connector.