Controlled electromagnetic induction detonation system for initiation of a detonatable material

Abstract

The controlled electromagnetic induction detonation system for initiation of a detonatable material system [( 10 )] includes an automated radio charge (ARCH) module connectable to an electric detonator [( 24 )], a transducer module [( 14 )] for providing operational power by electromagnetic induction to the ARCH module [( 18 )], and a remote controller [( 12 )] for sending instructions to the transducer module [( 14 )] from a location remote from the detonator [( 24 )]. Upon completion of an arming sequence, the transducer module [( 14 )] generates an electromagnetic field which is picked up by a coil in the ARCH module [( 18 )] and used to power the ARCH module [( 18 )] and provide a detonation current for the detonator [( 24 )]. The transducer module [( 14 )] or at least a coil thereof which produces the electromagnetic field is supported on or in a stemming bar [( 16 )] which in turn acts as a core of an electromagnet confining the magnetic flux for pick up by the ARCH module [( 18 )]. Multilevel access control and interlock systems operate between the remote controller [( 12 )], transducer unit [( 14 )] and the ARCH module [( 18 )] to reduce the likelihood of unintentional initiation of the detonator [( 24 )].

The claims defining the invention are as follows:  
     
         1 . A controlled electromagnetic induction detonation system for initiating a detonatable material, the system including: 
 an automated radio charge (ARCH) module for delivering an electric detonation current to a detonatable material, said ARCH module including a power circuit for extracting power by means of electromagnetic induction from a electromagnetic field generated remotely from the ARCH module, the power circuit providing operational power for the ARCH module and the electric detonation current, and means for receiving and decoding radio transmitted control signals including a FIRE code, the verified receipt of which causes the ARCH module to deliver said current to and thereby initiate the detonatable material.    
     
     
         2 . A system according to  claim 1  wherein the means for receiving and decoding the control signal extracts the control signal from said electromagnetic field.  
     
     
         3 . A system according to  claim 2  wherein said ARCH module further includes an output switch through which said electronic detonation current must flow in order to initiate the detonatable material, said switch configured to provide a short circuit output to the detonatable material until receipt and verification of said FIRE code, in which instance, said switch is operated to remove said short circuit and allow the electronic detonation current to flow to the detonatable material.  
     
     
         4 . A system according to  claim 3  further including a transducer unit having a power supply for supplying power to electromagnetic field generating means for generating said electromagnetic field and radio transceiver means for radio transmitting said control signals to the ARCH module.  
     
     
         5 . A system according to  claim 4  wherein said transducer unit further includes means for impressing said control signals onto said electromagnetic field so that said radio transceiver means transmits both said electromagnetic field and said control signals to said ARCH module.  
     
     
         6 . A system according to  claim 5  further including a stemming bar for stemming a hole in which said ARCH module and detonator can be deposited and wherein said transducer unit includes a coil for generating said electromagnetic field, said coil mounted on or in the stemming bar so that lines of magnetic flux pass through the stemming bar and link with the power circuit to transfer operational power to the ARCH module by electromagnetic induction.  
     
     
         7 . A system according to  claim 5  wherein said transducer unit includes a mode switch switchable between a LOCAL mode and a REMOTE mode of operation, wherein in said LOCAL mode of operation, a user can manually input instructions to said transducer unit for radio transmission to said ARCH module and wherein in said REMOTE mode of operation, a user can input instructions to said transducer unit via a remote controller unit.  
     
     
         8 . A system according to  claim 7  wherein said transducer unit includes means for manual entry of instructions and a timer means both operationally associated with said mode switch whereby on switching said mode switch to the LOCAL mode, a user must enter via said entry means a valid identification number recognised by said transducer unit within a predetermined period of time timed by said timer means in order for further user instructions to be acted upon by said transducer unit, and in the absence of the entry of a valid identification number within said time period said transducer unit automatically shuts down so as to be non responsive to user input instructions for a second period of time timed by said timer means.  
     
     
         9 . A system according to  claim 8  wherein said transducer unit includes an ARM switch functional when said transducer unit is in the LOCAL mode of operation which, when activated causes said electric field generating means to generate said electromagnetic field.  
     
     
         10 . A system according to  claim 9  wherein said transducer unit includes a FIRE switch functional when said transducer unit is in the LOCAL mode of operation and which when activated within a predetermined time period after activation of the ARM switch causes the transducer unit to transmit the FIRE code to the ARCH module.  
     
     
         11 . A system according to  claim 7  further including a remote controller unit by which a user can communicate instructions to said transducer unit from a location remote from said transducer unit.  
     
     
         12 . A system according to  claim 11  wherein said remote controller unit includes means for the manual entry of instructions by which a user must enter a valid identification number within a predetermined time period in order for said remote controller to establish a radio communication link with said transducer unit.  
     
     
         13 . A system according to  claim 12  wherein said remote controller unit includes processor means for generating a unique identification code word which is continuously transmitted until an acknowledgment signal is received from said transducer unit corresponding to said identification code word, and wherein in the absence of receipt of said acknowledge signal within a predetermined time period said remote controller unit enters a RESET mode in which a user must once again enter a valid identification number to reinitiate the establishment of the radio communication link with said transducer unit.  
     
     
         14 . A system according to  claim 13  wherein said remote controller unit further includes an ARM switch which upon activation, when a radio communication link has been established with said transducer unit, causes the remote controller unit to transmit an ARM code to transducer unit upon which said transducer unit generates said electromagnetic field.  
     
     
         15 . A system according to  claim 14  wherein said transducer unit sends an acknowledgment signal to said remote controller unit upon receipt of the ARM code and said transducer unit thereafter initiates its timer means to time a first period within which to receive a FIRE code from said remote controller unit, wherein the absence of receipt of said FIRE code within said first period said transducer unit automatically shuts down for a second period of time.  
     
     
         16 . A system according to  claim 15  wherein said remote control unit includes a FIRE switch, which, when activated causes the remote control unit to transmit a FIRE code to said transducer unit which in turn upon on verified receipt thereof retransmits the FIRE code to said ARCH module.  
     
     
         17 . A system according to  claim 16  wherein the FIRE code transmitted by the remote controller to transducer unit is different to the FIRE code retransmitted by the transducer unit to the ARCH module.  
     
     
         18 . A controlled electromagnetic induction detonation system for decoupled in hole initiation of an energetic substance, said system including: 
 an automated radio charge (ARCH) module coupled to an energetic substance and deposited in a hole formed in a hard material, the ARCH module having a power circuit for extracting by means of electromagnetic induction operational power from a remotely generated electromagnetic field, the power circuit providing operational power for the ARCH module and arranged to generate a detonation current deliverable to the energetic material, and means for receiving and decoding radio transmitted control signals including a FIRE code, the verified receipt of which causes delivery of the detonation current to the energetic material;    a stemming bar for stemming the hole in which the energetic material and arch module are deposited; and,    a transducer unit for radio transmitting said control signals, said transducer unit having a coil for generating the electromagnetic field, the coil locatable about an end of the stemming bar external of the hole so that lines of magnetic flux pass through the stemming bar and link with the power circuit to effect the transfer of operational power to the ARCH module by electromagnetic induction.