Wireless detonator assembly

Abstract

A wireless detonator assembly which comprises an initiator and a housing arrangement which includes a power supply, a processing module and a connection arrangement which is engageable with the initiator and which then electrically connects the power supply to the processing module.

Description

INT1613 / MAJR / WSDETN1301WIRELESS DETONATOR ASSEMBLYBACKGROUND OF THE INVENTION

[0001] This invention relates to a wireless detonator assembly.

[0002] A wireless detonator assembly when installed in a borehole must be capable of receiving through-the-earth signals transmitted from a control facility. This requirement imposes substantial constraints on the detonator assembly in that provision must be made for an appropriate antenna arrangement which can receive a through-the-earth signal, a processor which can process signals which are sent to the detonator assembly, an onboard power supply, an initiator and a booster.

[0003] Additional issues include adequate facilities for storage and differing end use power requirements on the power supply.

[0004] If the detonator assembly is constructed in assembled form under factory conditions then significant transport and regulatory factors arise. It is therefore appropriate and desirable to make use of an arrangement wherein components of the detonator assembly which are made under factory conditions, can be transported with relative ease and in safety to a blast site at which the components can readily be connected to one another to produce a functional device.

[0005] Solutions have been developed and are being applied currently in the blasting field, in which a housing containing an antenna, a processor and a power supply are connectable to the initiator, which is connected, when appropriate, to a booster. Some designs based on thisINT1613 / MAJR / WSDETN1302 solution present problems of limited capability of disintegration (disassembly) for transportation purposes, bulkiness and adaptability for varying technology requirements.

[0006] An object of the invention is to address, at least to some extent, the aforementioned issues. SUMMARY OF THE INVENTION

[0007] This invention provides a wireless detonator assembly which comprises an initiator and a housing arrangement which includes a power supply, a processing module and a connection arrangement which is engageable with the initiator and which then electrically connects the power supply to the processing module.

[0008] The initiator thus functions as a switch to enable the power supply to be connected to the processing module.

[0009] The initiator may include an elongate holder with a first end, an opposed second end, a projection for example in the form of a shoulder at or near the first end, and electrical contacts at the first end - preferably the electrical contacts are on an outer surface of the holder.

[0010] The electrical contacts may comprise a first contact and spaced apart second and third contacts. The first contact may extend circumferentially around the holder. The second and third contacts may be on opposed sides of the holder.

[0011] The second and third contacts may be connected to a firing structure inside the elongate holder.INT1613 / MAJR / WSDETN1303

[0012] The detonator assembly may include a booster which comprises a booster housing which contains an explosive material wherein a passage extends inside the housing for example through the explosive material. The second end of the elongate holder may, in use, be insertable into the passage preferably with a sliding action.

[0013] The housing arrangement of the wireless detonator assembly may include a first housing in which the power source and the connection arrangement are mounted and a second housing within which the processing module is located.

[0014] The second housing may additionally include an antenna structure.

[0015] The second housing may include a coupling end and the first housing may include a connecting end. The coupling end and the connecting end may be connected to each other in any appropriate way for example with a screw action, or by using a snap-lock or clip action, or the like.

[0016] The first housing may include an initiator end which is remote from the connecting end. The first housing may include a volume, inside the housing at the initiating end, which is configured to receive the first end of the initiator and the first, second and third contacts.

[0017] The projection (shoulder) on the initiator may, in use, abut a rim in the volume.

[0018] The connection arrangement in the first housing may include one contact but preferably a first contact pair configured to engage with the first contact on the initiator and a second contact pair configured to engage with the second and third contacts on the initiator respectively.INT1613 / MAJR / WSDETN1304

[0019] The first contact pair and the second contact pair may comprise respective spring contacts.

[0020] Electrical contact between the first contact pair and the first contact on the initiator may cause power to be supplied to the processing module. In this respect the first contact on the initiator may be regarded as exhibiting a switching action when brought into electrical contact with the first contact pair.

[0021] The second housing, at the coupling end, may include a screw thread configured to be threadedly engaged with a complementary screw thread at the connecting end of the first housing.

[0022] The second housing may include an elongate member which extends inside the second housing adjacent the coupling end. Contacts which are insulated from one another may be carried on the elongate member. A first set of these contacts, conveniently referred to as power contacts, may be configured to engage with leads which extend from the power supply in the first housing. A second pair of contacts on the elongate member, conveniently referred to as processing contacts, may be configured to engage electrically via suitable conductors with the spaced second and third contacts on the initiator.BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The invention is further described by way of example with reference to the accompanying drawings in which :INT1613 / MAJR / WSDETN1305Figure 1 schematically illustrates a wireless detonator assembly according to the invention with the various components which make up the detonator assembly connected to one another,Figure 2 has an upper drawing which shows from one side an initiator displaced from a first housing - in use the initiator is connected to the first housing, and a lower drawing which shows from one side a second housing to which the first housing can be connected,Figure 3 shows in perspective and on an enlarged scale an end of the first housing referred to as an initiator end and a part of the initiator which is engageable therewith,Figure 4 is similar to Figure 3 but illustrating the initiator engaged with the first housing,Figure 5 is a side view in section showing the first housing with the initiator engaged therewith, Figure 6 illustrates on an enlarged scale and in perspective the manner in which a booster housing is engaged with an initiator end of the first housing.Figure 7 shows from one side a sub-housing with which a processing module and an antenna arrangement are engageable,Figure 8 illustrates from one side and in section a second housing in which the sub-housing, processing module and antenna arrangement of Figure 7 are mounted, andFigure 9 illustrates on an enlarged scale and in section the making of electrical connections to contacts in the second housing.INT1613 / MAJR / WSDETN1306DESCRIPTION OF PREFERRED EMBODIMENT

[0024] Figure 1 of the accompanying drawings illustrates schematically and from one side a detonator assembly 10 according to the invention.

[0025] The detonator assembly includes a booster 12, a first housing 14 and a second housing 16. The booster 12 comprises a booster housing 20 which has a sealed end 22 and an opposing connection end 24. As is known in the art the booster contains explosive material 26. An elongate passage 28 extends inside the booster through the explosive material from the connection end 24.

[0026] The first housing 14 is elongate cylindrical and includes an initiator end 30 and an opposed connecting end 32. The first housing includes, mounted inside the housing and shown in dotted outline a power supply 34 and a connection arrangement 36.

[0027] The second housing 16 is elongate and tubular and includes a sealed end 40 and an opposing second end referred to as a coupling end 42. Schematically shown in dotted outline in Figure 1 are an antenna arrangement 44 and a processing module 46.

[0028] Figure 2 shows the first housing 14 from one side and an initiator 50.

[0029] The initiator comprises an elongate tubular holder 52 which is of substantially conventional internal construction - not further described herein. The holder has a first end 54 and an opposed second end 56. An annular projection 58 is on the holder 52 near the second end. The annular projection comprises a seal and locating formations 60 and a shoulder 62. As is shown in Figure 3 the holder 52 to the left of the projection 58 is enlarged with two opposed flat sides 64 and 66 respectively. A first conductive contact 70 extends in the form of a bandINT1613 / MAJR / WSDETN1307 around the initiator housing adjacent the projection 58. Each of the flat sides 64 and 66 carries a respective plate conductor 72 and 74. The plate conductors 72 and 74 are connected to conductive leads 76 and 78 shown in dotted form in Figure 2 which are connected to an initiating component 80 inside the explosive material 82 in the holder 52.

[0030] Figure 4 illustrates on an enlarged scale the initiator end 30 of the first housing 14. The housing includes a volume 86 adjacent the initiator end which is configured to receive the shaped first end 52 of the initiator 50. The volume 86 has opposed flat surfaces 82 and 84 which are configured to receive and tightly engage with the flat sides 64 and 66 of the initiator. Spring loaded contacts 92 and 94 respectively are positioned in these flat surfaces. Additional spring contacts 96 and 98 respectively - see as well Figure 5 - are inside the volume. These contacts are between the open end of the volume 86 and the contacts 92 and 94. The contacts 96 and 98 oppose each other and are displaced by an angle of 90° relative to the opposing contacts 92 and 94.

[0031] The volume 86 presents a rim 100 to the initiator.

[0032] Figure 6 illustrates the manner in which the booster 12 is engaged with the first housing. The booster at the connection end 24 has a short cylindrical formation 104 with opposed projecting bayonet formations 106 and 108. The volume 86 at the initiator end 30 of the first housing has opposed grooves 110 and 112 which extend in an axial direction.

[0033] Referring to Figure 6 when the booster housing 20 is engaged with the first housing 12 the initiator holder 52 slides into the passage 28 and the projections 106 and 108 are brought into alignment with the grooves 110 and 112 respectively. By twisting the booster housing 20 relative to the first housing 14 the projections 106 and 108 are engaged with what may beINT1613 / MAJR / WSDETN1308 referred to as a bayonet action with arcuate slots 116, 118 respectively which oppose each other on an inner surface 120 which surrounds the volume 86. In this way the booster 12 is firmly mechanically locked to the first housing 14.

[0034] As the bayonet action takes place the spring contacts 96 and 98 are brought into firm electrical contact with the band contact 70 at the first end of the initiator, and the spring contacts 92 and 94 are brought into firm electrical contact with the plate contacts 72 and 74 on the flat sides 64 and 66 of the initiator.

[0035] The first housing 14 has batteries 110, 112 respectively i.e. the power supply 34 shown in Figure 1 which are connected to the spring contacts 96 and 98 when the booster is connected to the first housing. This is shown in Figure 5. Opposing terminals on the batteries 110 and 112 are connected to spring contacts 114 and 116 respectively which extend to coupling contacts 118 and 120 which are close to the connection end 32 of the first housing. Two opposed elongate electrical leads 124 and 126 respectively extend inside the first housing from the plate contacts to spring loaded terminals 130 and 132 - see Figure 9, near the connection end 32.

[0036] Figure 7 illustrates a sub-housing 134 which is designed to carry the antenna arrangement 44 and the processing module 46 referred to in connection with Figure 1. The components 44 and 46 are carried on a printed circuit board 142A which is engageable, together with an adjacent printed circuit board 142B with a sliding action, as indicated in Figure 7, with the sub-housing 134. An elongate member 146 projects from the printed circuit boards. This member has a first contact pair 148 and 150 separated by means of insulation 152, and a second contact pair 154 and 156 separated by insulation 158. Insulation 160 separates theINT1613 / MAJR / WSDETN1309 contact 150 from the contact 154. The contact pair 148, 150 is carried on a portion of the member 146 which has a larger diameter than a portion which carries the contact pair 154, 156.

[0037] The processing module 46 includes processors, timers and other components as is known in the art configured to receive and transmit signals, and to carry out logic and control functions with integrity and test protocols as is known in the art. These aspects are not further described herein. The antenna arrangement 44 includes three antenna coils 44A, 44B and 44C which are mounted so that each coil is at a right angle to the other coils. This triaxial antenna arrangement is configured to receive wireless signals transmitted through-the-earth in a manner which ensures that the signal strength does not meaningfully vary due to the direction from which the signal to the detonator assembly is transmitted.

[0038] The sub-housing 134 includes snap connectors 170 and 172 and a threaded projecting end 174. As is shown in Figure 8 the snap connectors 170 and 172 engage with a firm action with corresponding recesses 180 and 182 on an inner surface of the second housing 16.

[0039] The contact pairs 148 and 150, and 154 and 156, on the elongate member 146 are connected via leads, not shown, which extend through the elongate member to terminals 186, 188, 190 and 192 respectively which are connected, as appropriate, to components on the printed circuit board 142B.

[0040] When the coupling end 42 is engaged with the connection end 32 of the first housing, as shown in enlarged detail in Figure 9 the contacts 130 and 132 come into firm electrical contact with the contacts 156 and 154 at a leading end of the elongate member, and the contacts 118 and 120 are brought into electrical engagement with the contacts 150 and 148 respectively.INT1613 / MAJR / WSDETN13010

[0041] Power is applied to the components in the second housing 16 by the connections which are made to the batteries 110 and 112 via the contacts 118 and 120. Control and operating signals from the processing module 46 are transmitted to the initiator 52 by the leads 126, 128 which, via the contacts 92 and 94 (Figure 3), are in electrical engagement with the plate contacts 72 and 74 at the first end of the initiator.

[0042] As the power supply is contained in the first housing which is separate from the processing module, the booster and the initiator, the different components of the detonator assembly can be transported more readily with safety. Additionally the manner in which the components are constructed is such that, on site, connections are done directly with ease. The detonator assembly is only powered once the initiator is in situ. It is possible to use a dummy initiator in place of the initiator thereby to connect the power supply to the processing module so as to power the assembly for tagging purposes.

[0043] Another factor is that the power supply includes the batteries 110, 112 and can be used with a neutral or earth point so that the batteries produce a positive voltage and a negative voltage, each with reference to the neutral or earth point - this is a facility which allows for bidirectional communication to take place between the processing module and a tagger, during installation. Also, the nature of the design of the first housing and the manner in which the batteries are mounted in the housing are such that the battery-capacity can be altered with relative ease to meet different end-use requirements.

Claims

INT1613 / MAJR / WSDETN13011CLAIMS1 . A wireless detonator assembly which comprises an initiator and a housing arrangement which includes a power supply, a processing module and a connection arrangement which is engageable with the initiator and which then electrically connects the power supply to the processing module.

2. The wireless detonator assembly according to claim 1 wherein the initiator functions as a switch to enable the power supply to be connected to the processing module.

3. The wireless detonator assembly according to claim 1 wherein the initiator includes an elongate holder with a first end, an opposed second end, a projection in the form of a shoulder at or near the first end, and electrical contacts which are on an outer surface of the holder, and which are located at the first end.

4. The wireless detonator assembly according to claim 3 wherein the electrical contacts comprise a first contact and spaced apart second and third contacts.

5. The wireless detonator assembly according to claim 4 wherein the first contact extends circumferentially around the holder and the second and third contacts are on opposed sides of the holder.

6. The wireless detonator assembly according to claim 4 wherein the second and third contacts are connected to a firing structure inside the elongate holder.

7. The wireless detonator assembly according to claim 3 which includes a booster which comprises a booster housing which contains an explosive material, and through which aINT1613 / MAJR / WSDETN13012 passage extends, and wherein the second end of the elongate holder, in use, is insertable into the passage with a sliding action.

8. The wireless detonator assembly according to claim 4 wherein the housing arrangement includes a first housing in which the power source and the connection arrangement are mounted and a second housing within which the processing module is located.

9. The wireless detonator assembly according to claim 8 wherein the second housing includes an antenna structure.

10. The wireless detonator assembly according to claim 8 wherein the second housing includes a coupling end, the first housing includes a connecting end and the coupling end and the connecting end are connected to each other.11 . The wireless detonator assembly according to claim 10 wherein the first housing includes an initiator end which is remote from the connecting end, and a volume, inside the housing at the initiating end, which is configured to receive a first end of the elongate holder and the first, second and third contacts.

12. The wireless detonator assembly according to claim 11 wherein the shoulder on the initiator, in use, abuts a rim in the volume.

13. The wireless detonator assembly according to claim 8 wherein the connection arrangement in the first housing includes a first contact pair configured to engage with the first contact on the initiator and a second contact pair configured to engage with the second and third contacts on the initiator respectively.INT1613 / MAJR / WSDETN1301314. The wireless detonator assembly according to claim 13 wherein the first contact pair and the second contact pair comprise respective spring contacts.

15. The wireless detonator assembly according to claim 13 wherein electrical contact between the first contact pair and the first contact on the initiator causes power to be supplied to the processing module.

16. The wireless detonator assembly according to claim 10 wherein the second housing, at the coupling end, includes a screw thread which is configured to be threadedly engaged with a complementary screw thread at the connecting end of the first housing.

17. The wireless detonator assembly according to claim 10 wherein the second housing includes an elongate member which extends inside the second housing adjacent the coupling end, and which carries contacts which are insulated from one another18. The wireless detonator assembly according to claim 17 wherein the contacts comprises a first set of contacts, which are configured to engage with leads which extend from the power supply in the first housing and a second pair of contacts which are configured to engage electrically via conductors with the spaced apart second and third contacts on the initiator.

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