Electronic detonator system

Abstract

A method for firing electronic detonators in an electronic detonator system, said detonators being connected to a control unit via a bus. A firing command or a test firing command is sent from the control unit to the detonators, which start countdown of a delay time stored in each detonator at a synchronising point which is delayed relative to said command. On completion of the countdown, the detonators are caused, in the case of a firing command, to detonate, and in the case of a test firing command, to give a response at the point where they should have detonated if a firing command had been involved. The delayed synchronisation allows checking and control of the detonators after said command has been received. The invention also comprises an analogous method in a system with a plurality of slave control units, to which a plurality of detonators are connected, and a main control unit, the system being controlled at the command of the main control unit.

1 . A method for firing electronic detonators ( 10 ) included in an electronic detonator system, said detonator system comprising a control unit ( 11 .  12 ) and a bus ( 13 ), the electronic detonators ( 10 ) being connected to the control unit ( 11 ,  12 ) via said bus ( 13 ) and communication between the control unit ( 11 ,  12 ) and the electronic detonators ( 10 ) occurring on the bus ( 13 ), said method being characterized by the steps of 
 sending a firing command ( 400 ) from the control unit on the bus,    receiving ( 401 ) said firing command in said electronic detonators,    setting, in response to said received firing command, the electronic detonators in a ready state,    awaiting a synchronising signal, which is delayed in relation to the firing command and which is sent by the control unit and indicates a synchronising point which is common to said detonators, the synchronising point preferably being the time of receiving said synchronising signal,    sending a synchronising signal ( 410 ) from the control unit on the bus,    starting, at the synchronising point, countdown in each electronic detonator of a delay time ( 411 ) stored therein, and    causing, on completion of said countdown, each detonator to detonate ( 440 ),    wherein communication from the control unit to the electronic detonators is performed by means of digital data packets and wherein communication from the electronic detonators to the control unit is preferably performed by influence, detectable by the control unit, on the bus, particularly analog load pulses.    
     
     
         2 . A method as claimed in  claim 1 , wherein the step of awaiting said delayed synchronising signal comprises the step of receiving in the detonators a predetermined number of digital data packets, whereupon the detonators are in a state that allows receipt of a synchronising signal, the synchronising signal preferably being the subsequent digital data packet.  
     
     
         3 . A method as claimed in any one of the preceding claims, wherein the synchronising point is the time of receiving in each detonator a predetermined data bit in a predetermined data packet, which is sent by the control unit after said firing command has been sent.  
     
     
         4 . A method as claimed in any one of the preceding claims, wherein the control unit, subsequent to the firing command and prior to the synchronising point, sends a predetermined number of data packets, whereby communication with, and thus control and checking of, the detonators is allowed after they have received said firing command and thus are in said ready state.  
     
     
         5 . A method as claimed in any one of the preceding claims, wherein a check that each detonator has received the firing command is performed before the synchronising signal is sent on the bus.  
     
     
         6 . A method as claimed in any one of the preceding claims, wherein a check that no detonator has an error indicator is performed before the synchronising signal is sent on the bus.  
     
     
         7 . A method as claimed in any one of the preceding claims, wherein at least one of the data packets that are not used for communication with the detonators comprises a further firing command.  
     
     
         8 . A method as claimed in any one of the preceding claims, wherein all data bits in said firing command, comprising also overhead bits if any, are identical and preferably consist of binary zeros.  
     
     
         9 . A method for firing electronic detonators ( 10 ) included in an electronic detonator system, said detonator system comprising a main control unit ( 62 ), at least one slave control unit ( 64 ) and a bus ( 13 ), the electronic detonators ( 10 ) being connected to said slave control unit ( 64 ) via said bus ( 13 ) and communication between the slave control unit ( 64 ) and the electronic detonators ( 10 ) being performed on the bus ( 13 ), said method being characterized by the steps of 
 ordering, by means of the main control unit, the slave control unit to send ( 400 ) a firing command on the bus,    receiving ( 401 ) said firing command in said electronic detonators,    setting, in response to said received firing command, the electronic detonators in a ready state,    awaiting a synchronising signal which is delayed in relation to the firing command and which is sent by the slave control unit and indicates a synchronising point which is common to said detonators, the synchronising point preferably being the time of receiving said synchronising signal,    sending a synchronising signal ( 410 ) from the slave control unit on the bus,    starting, at the synchronising point, countdown in each electronic detonator of a delay time ( 411 ) stored therein, and    causing, on completion of said countdown, each detonator to detonate ( 440 ),    wherein the slave control unit's ( 64 ) sending of the synchronising signal is performed at the command of the main control unit ( 62 ), whereby a plurality of slave control units are allowed to simultaneously send synchronising signals.    
     
     
         10 . A method as claimed in  claim 9 , wherein communication from the control unit to the electronic detonators is performed by means of digital data packets and communication from the electronic detonators to the slave control unit is preferably performed by influence, detectable by the slave control unit, on the bus, particularly analog load pulses.  
     
     
         11 . A method as claimed in  claim 10 , wherein the step of awaiting said delayed synchronising signal comprises the step of receiving in the detonators a predetermined number of digital data packets, whereupon the detonators are in a state which allows receipt of a synchronising signal, the synchronising signal preferably being the subsequent digital data packet.  
     
     
         12 . A method as claimed in any one of claims  9 - 11 , wherein the synchronising point is the time of receiving in each detonator a predetermined data bit in a predetermined data packet, which is sent by the slave control unit after said firing command has been sent.  
     
     
         13 . A method as claimed in any one of claims  9 - 12 , wherein the slave control unit, subsequent to the firing command and prior to the synchronising point, sends a predetermined number of data packets, whereby communication with, and thus control and checking of, the detonators is allowed after they have received said firing command and thus are in said ready state.  
     
     
         14 . A method as claimed in any one of claims  9 - 13 , wherein communication between the main control unit and the slave control unit is performed by means of radio communication.  
     
     
         15 . A method as claimed in any one of claims  9 - 13 , wherein communication between the main control unit and the slave control unit is performed via a bus in the form of a physical cable.  
     
     
         16 . A method as claimed in any one of claims  9 - 15 , wherein a check that each detonator has received the firing command is performed before the synchronising signal is sent on the bus.  
     
     
         17 . A method as claimed in any one of claims  9 - 16 , wherein a check that no detonator has an error indicator is performed before the synchronising signal is sent on the bus.  
     
     
         18 . A method as claimed in any one of claims  9 - 17 , wherein at least one of the data packets that are not used for communication with the detonators comprises a further firing command.  
     
     
         19 . A method as claimed in any one of claims  9 - 18 , wherein all data bits in said firing command, comprising also overhead bits if any, are identical, and preferably consist of binary zeros.  
     
     
         20 . A method for firing electronic detonators ( 10 ) included in an electronic detonator system, said detonator system comprising a control unit ( 11 ,  12 ) and a bus ( 13 ), the electronic detonators ( 10 ) being connected to the control unit ( 11 ,  12 ) via said bus ( 13 ) and communication between the control unit ( 11 ,  12 ) and the electronic detonators ( 10 ) being performed on the bus ( 13 ), said method being characterized by the steps of 
 sending a test firing command ( 710 ) from the control unit on the bus,    receiving ( 711 ) said test firing command in said electronic detonators,    awaiting a synchronising signal which is delayed in relation to the test firing command and which is sent by the control unit and indicates a synchronising point which is common to said detonators, the synchronising point preferably being the time of receiving said synchronising signal,    sending a synchronising signal ( 720 ) from the control unit on the bus,    starting, at the synchronising point, countdown in each electronic detonator of a delay time ( 730 ) stored therein, 
 giving, on completion of said countdown, a response ( 740 ) from each detonator,  
 receiving ( 750 ) said response in the control unit, and  
 on the basis of these responses, especially the time distribution thereof, making an evaluation of the electronic detonator system,  
 wherein communication from the control unit to the electronic detonators is performed by means of digital data packets and communication from the electronic detonators to the control unit is preferably performed by means of influence, detectable by the control unit, on the bus, particularly analog load pulses.  
   
     
     
         21 . A method as claimed in  claim 20 , wherein the step of awaiting said delayed synchronising signal comprises the step of receiving in the detectors a predetermined number of digital data packets, whereupon the detonators are in a state that allows receipt of a synchronising signal, the synchronising signal preferably being the subsequent digital data packet.  
     
     
         22 . A method as claimed in  claim 20  or  21 , wherein the synchronising point is the time of receiving in each detonator a predetermined data bit in a predetermined data packet, which is sent by the control unit after said test firing command has been sent.  
     
     
         23 . A method as claimed in any one of claims  20 - 22 , wherein the test firing command indicates a scale factor, by which the delay time stored in each detonator is multiplied before said countdown thereof is started, whereby a high-resolution test firing is provided.  
     
     
         24 . A method for firing electronic detonators ( 10 ) included in an electronic detonator system, said detonator system comprising a main control unit ( 62 ), at least one slave control unit ( 64 ) and a bus ( 13 ), the electronic detonators ( 10 ) being connected to said slave control unit ( 64 ) via said bus ( 13 ) and communication between the slave control unit ( 64 ) and the electronic detonators ( 10 ) being performed on the bus ( 13 ), said method being characterized by the steps of 
 commanding, by means of the main control unit, the slave control unit to send a test firing command ( 710 ) on the bus,    receiving the test firing command ( 711 ) in said electronic detonators,    awaiting a synchronising signal which is delayed in relation to the test firing command and which is sent by the slave control unit and indicates a synchronising point which is common to said detonators, the synchronising point preferably being the time of receiving said synchronising signal,    sending a synchronising signal ( 720 ) from the slave control unit on the bus,    starting at the synchronising point countdown in each electronic detonator of a delay time ( 730 ) stored therein, 
 giving, on completion of said countdown, a response ( 740 ) from each detonator,  
 receiving said response ( 750 ) in the slave control unit, and  
 on the basis of these responses, especially the time distribution thereof, making an evaluation of the electronic detonator system,  
 wherein the slave control unit's sending of the synchronising signal is performed at the command of the main control unit, whereby a plurality of slave control units are allowed to simultaneously give synchronising signals.  
   
     
     
         25 . A method as claimed  claim 24 , wherein communication from the slave control unit to the electronic detonators is performed by means of digital data packets and communication from the electronic detonators to the slave control unit is preferably performed by influence, detectable by the slave control unit, on the bus, particularly analog load pulses.  
     
     
         26 . A method as claimed in  claim 24  or  25 , wherein the step of awaiting said delayed synchronising signal comprises the steps of receiving in the detonators a predetermined number of digital data packets, whereupon the detonators are in a state which allows receipt of a synchronising signal, the synchronising signal preferably being the subsequent digital data packet.  
     
     
         27 . A method as claimed in any one of claims  24 - 26 , wherein the synchronising point is the time of receiving in each detonator a predetermined data bit in a predetermined data packet, which is sent by the slave control unit after said test firing command has been sent.  
     
     
         28 . A method as claimed in any one of claims  24 - 27 , wherein the test firing command indicates a scale factor, by which the delay time stored in each detonator is multiplied before said countdown thereof is started, whereby a high resolution test firing is provided.  
     
     
         29 . An electronic detonator system, comprising a control unit ( 11 ,  12 ), a plurality of electronic detonators ( 10 ) and a bus ( 13 ), which connects said detonators ( 10 ) to the control unit ( 11 ,  12 ), the detonators ( 10 ) being controllable and checkable by means of digital data packets which are sent on the bus ( 13 ) from the control unit ( 11 ,  12 ), and are adapted to detonate after a delay time established for each detonator has elapsed from a synchronising point which is common to all detonators, in response to a firing command sent from the control unit, characterised in that said synchronising point occurs after said firing command has been received by said detonators, and the control unit ( 11 ,  12 ) is adapted to communicate with the detonators ( 10 ) also after these have received the firing command and, in any case, up to the synchronising point, 
 wherein said electronic detonators ( 10 ) are adapted to effect communication from the electronic detonators ( 10 ) to the control unit ( 11 ,  12 ) by means of influence, particularly analog load pulses, on the bus ( 13 ), said influence being detectable by the control unit.