CA1234205A - Electrical sequential firing system - Google Patents
Electrical sequential firing systemInfo
- Publication number
- CA1234205A CA1234205A CA000469085A CA469085A CA1234205A CA 1234205 A CA1234205 A CA 1234205A CA 000469085 A CA000469085 A CA 000469085A CA 469085 A CA469085 A CA 469085A CA 1234205 A CA1234205 A CA 1234205A
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Abstract
A B S T R A C T
This invention relates to sequential blasting utilising electronic circuitry to steer detonating pulses to suc-cessive detonators. Modules are provided which contain a two-terminal element that has the characteristic that in its first normal state it has a high resistance in at least one direction and it may be changed into a second state in which it has a low resistance in both direc-tions by a suitable pulse. Further, a detonating signal does not flow from one power line to the other through the particular module that is being addressed, but from one side of one module through a connecting link and then through the other module. Thus, each module has an input steering terminal and an output steering terminal, with the output steering terminal of each module connec-ted to the input steering terminal of the next module.
Then, in use, current flows from one power line to a power terminal of one module, through its output steer-ing terminal to the input terminal of the next module, through that module and to the other power line. Thus, with each detonating pulse, a detonator is fused and one of the elements passes into its second conducting state.
As the detonator goes into a non-conducting configura-tion the next pulse is steered via the element that is now conducting to the next module.
This invention relates to sequential blasting utilising electronic circuitry to steer detonating pulses to suc-cessive detonators. Modules are provided which contain a two-terminal element that has the characteristic that in its first normal state it has a high resistance in at least one direction and it may be changed into a second state in which it has a low resistance in both direc-tions by a suitable pulse. Further, a detonating signal does not flow from one power line to the other through the particular module that is being addressed, but from one side of one module through a connecting link and then through the other module. Thus, each module has an input steering terminal and an output steering terminal, with the output steering terminal of each module connec-ted to the input steering terminal of the next module.
Then, in use, current flows from one power line to a power terminal of one module, through its output steer-ing terminal to the input terminal of the next module, through that module and to the other power line. Thus, with each detonating pulse, a detonator is fused and one of the elements passes into its second conducting state.
As the detonator goes into a non-conducting configura-tion the next pulse is steered via the element that is now conducting to the next module.
Description
~23~5 This invention relates to an electrically operable sequential activation muddle and system and to a power source for operating such a sequential activation system. In particular the invention relates to a module and system for sequentially active-tying a device that has a low resistance prior to being activated and a high resistance thereafter. A device of this type is a detonator.
According to the invention there is provided an elect tribally operable sequential activation module for supplying an activation signal to a device which has a low resistance prior to being activated and a high resistance thereafter the module being connectable in a series with other similar modules to sequentially activate a number of the devices the module i tlCl using a first convertible element which has two terminals and in its normal first state has a high resistance in at least one direction from its first terminal -to its second terminal and which changes to a second state in which it has a low resistance in both directions when a first signal having a predetermined ----characteristic is applied across the element, the element thereafter retaining the low resistance in both directions when the first signal is removed;
a first and a second power terminal by means o-F which the module is connectable to an electrical power source for supplying the first signal and an activating signal;
a -first and a second device terminal by means of which the device is connectable to the module;
an input steering terminal, and an output steering terminal which is connectable to the input steering temlinal of a succeeding module in a series thereof with the first device terminal connected to the input steering temlinal;
the second device termirldl connected to the output steering terminal;
the second device terminal also being connected to the second terminal of the first element; and the first terminal of the first element being connected to the second power terminal.
The device may be activated by the sane signal that changes the first element, so that the first signal and active-tying signal are one signal.
The first convertible elenlent may, in its first state, have a high resistance in both directions.
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Although it has been indicated that the device has a low resistance prior to being activated and a high resistance thereafter, it will be understood by those skilled in the art that the device nay be composite in structure, comprising a unit which is activated and has a series unit that initially has the low resistance and thereafter the high resistance. Further, as the same effect will be obtained it the series unit is located in series with either the first or second device terminal the module itself may include the series unit in series with the first or second device te~linals. It will accordingly be understood that the term "device which has a low resistance prior to being activated and a high resistance thereafter" is meant to include a composite device as described above, and a device which has a low resistance also after activation in combination with a unit that could be regarded as forming part of the module.
It will be appreciated that the first element may be of any suitable material 9 form or construction. However, the apply-cant believes that the most suitable material is a semiconductor material. Further, the element may have a single junction and may, for example, be a zoner diode. The element may have two junctions, in which case it may be a bipolar transistor with only the collector and emitter being used, these forming the terminals of the element. With a zoner diode or bipolar transistor, it has been found that if a voltage is applied across the diode or transistor that is just above the breakdown voltage of the diode or transistor, and the current through the diode or ^~,~
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transistor maintained between certain predetermined levels for a sufficient period of time, then a conducting path is formed across -the diode or transistor, which remains -there after the voltage is removed. Further, this conducting path can then carry a greater current than that which formed the path without being destroyed.
Those skilled in the art will appreciate that in its basic form the module has a first power tenninal that is floe-tinge If only one module were to be connected to the power supply then there would not be a path from one power terminal to the other via a device connected to the device terminals of the module. Ivory, the modules are not used on their own but in a series, with the input steering terminal of each module in the series, except for a first nodule in the series, being connected to the output steering terminal o-f the preceding module and with their power terminals being interconnected. Further, the input steering terminal of the first module in the series is connected directly to its first power terminal or via a switch. Thus, in use, current will -flow through the input steering terminal of the first nodule to its first device terminal, through the device to the second device terminal of the first module, and through the first element of the first module in the series. This will have the effect of changing this first element into its second state, so that the voltage across the device increases, thereby active-tying it. As there is now a conducting path between the second pillager terminal and the output steering terminal of the first Jo :' ..., Jo - 6 _ ~23~
module, there Jill then be a path through the next module if it is connected in an "inverted" manner, i.e. with its first power terminal connected to the second power terminal of the first module and its second power terminal connected to the first power terminal of the first module. Thus the modules are connected with opposite polarity and are successively operated by pulses of opposite polarity.
Accordingly the invention further provides an electric gaily operable sequential activation system, which includes a plurality of modules in accordance with the invention arranged in a series with the input steering terminal of each module other than the first module being connected to the output steering terminal of the preceding module, and the first and second power terminals of the modules being interconnected.
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As indicated above the modules may alternate, with the first and second power terminals of each module being connected to the second and first power terminals, respectively of an adjacent module.
In order to ensure that only one element is changed at a time, that only one device is activated at a time and that there is not a path which will have a decreasing resistance as the number of modules in the series increases, each module may include a signal blocking means which is connected between the second device terminal and the output steering tenninal, and/or between the input steering terminal and the first device term-I,, j _ 7 _ ~23~2(3S
net, and/or between the second device terminal and the second terminal of the -first element.
The signal blocking means may be a resistor, diode or any suitable component. It may also have the same characters-tics as the first element, and may thus also be a bipolar transistor, the collector and emitter thereof being used.
If the signal blocking means is a diode, it may have its anode connected to the second device termirlal and its cathode connected -to the output steering terminal. Alternatively, the anode may be connected to the input steering terminal and the cathode may be connected to the first device terminal. Further, if the signal blacken diode is connected between the second device terminal and the first element then its anode is connected to the second device terminal and its cathode is connected to the second terminal of the first element.
If the first element is an NUN bipolar transistor, then its emitter may be connected to the second device terminal and its collector may be connected to the second power terminal.
Alternatively, it may have its collector connected to the second device terminal and its emitter to the second power terminal.
The system may have different kinds of modules. Thus the systenlnlay have two groups of modules, with modules of one group alternating with those of the other group.
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The module may include a second convertible element which has two ten~linals and in its normal First state has a high resistance in at least one direction prom its first terminal to its second terminal and which changes to a second state in which it has a low resistance in both directions when a second signal having a predetermined characteristic is applied across the eye-mint, the element thereafter having the low resistance value in both directions when the second signal is removed, the first terminal of the second element being connected to the first power tenninal and the second terminal of the second element being connected to the output steering terminal or the second device terminal, with the first element further being such that it changes into a third state when it is in its low resistance second state and a third signal having a predetermined character fistic is applied across the first element, in which third state it has a high resistance in both directions.
The second element may be substantially the same as the first element. Thus, the second elennent may also be a semiconductor, and may also have ore or two junctions. Thus, it may also be a zoner diode or a bipolar transistor. It it is an NUN transistor then it may have its collector connected to the first power terminal and its emitter connected to the output steering terminal or the second device terminal.
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Tulsa skilled in the art will appreciate that when a transistor is converted into its conducting state as described above and a current of sufficient magnitude is passed there-through for long enough, it will be damaged to such an extent that it forms an open circuit.
With modules having first and second elements it is possible to form a system without "inverting" any modules. Thus all the first power terminals are connected together and all the second power terminals are connected together. Then, the modules are supplied with a series of pulses, there being a positive pulse which changes the first element of the first module into its second state and activates the -first device, a subsequent pulse of negative polarity which changes the second element of the first module into its second state and then increases in magnitude to change the first element of the first module into its third non-conducting state, with the sequence repeating.
Each successive positive pulse causes the first element of the next module in the series to change into its second state and the device associated with that module to be activated.
The invention accordingly extends further to a power source for an electrically operable sequential activation system, which supplies a repeating group of pulses, a first pulse in each group being of a predete~ined polarity and a second pulse in each group being of the opposite polarity and which supplies second pulses that have an initial predetermined magnitude and thereafter have a greater magnitude.
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The invention is now described by way ox examples with reference to the accompanying drawings, in which:-Figures 1 to 8 show different electrically operable sequent trial activation modules in accordance with the invention; and Figures 9 to 12 show sequential activation systems in accord dance with the invention; and Figure 13 shows a power source in accordance with the invent lion.
Referring to Figure 1, shown therein designated generally by reference numeral 10 is an electrically operable sequential activation module -For supplying an activation signal to a detonator (not shown in Figure 1) which has a low resistance prior -to being activated and a high resistance thereafter. As is discussed herein below, the module 10 is connected in a series with other similar modules to form an activation system.
Thus, as shown in Figure 1, the module 10 has a first power Tylenol 11, a second power terminal 12, an input steering temlinal 13, an output steering tenninal 14, a first device terminal 15 and a second device terminal 16. The input steering tenninal 13 and the first device temlinal 15 are directly electrically connected by means of a conducting link 17.
Similarly, the second device tenninal 16 and the output steering terminal 14 are directly connected by means o-F a link 18. The second device terlninal 16 is also connected to the second power . . I.
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terminal 12 by means of d diode 19. The anode of the diode 19 is connected to the second device terminal 16 and the cathode is connected to the second power tenninal 12. It will be noted, that as the second device terminal 16 and the output steering terminal 14 are directly connected, the diode 19 is also, in effect, connected between the output steering terminal 14 and the second power terminal 12. The diode 19 is such that in its nodal First state it has a high resistance in the direction from the second power terminal 12 to the second device terminal 16 or output steering terminal 14; and a low resistance in the opposite direction. However, the diode 19 is such that when a current of a predetermined magnitude (in the order of 1 amp) is passed through the diode in its forward direction, for a suitable period of time, a conducting path is formed across the junction of the diode 19 such that it also has a low resistance from the second power terminal to the second device terminal 16.
Referring to Figure 23 a module 20 is shown therein which is similar to the module 10 of Figure 1. Thus, the module also has the various terminals designated in Figure 1, which terminals are similarly referenced. The input steering terminal 13 and the first device terminal 15 are also directly connected by means of the link 17. However, there is a blocking diode 21 between the second device terminal 16 and the output steering terminal 14, with its anode being connected to the second device terminal 16 and its cathode to the output steering terminal 14.
Instead of the diode 19 being connected between the second device terminal 16 and the second power terminal 12 as in the module 10, .
the module 20 has an NO transistor 22 connected there between.
The emitter 22.1 of the transistor 22 is connected to the second device -terminal 16 and the collector 22.2 is connected to the second power terminal 12. The base of the transistor 22 is not ~tilised and is left floating. The transistor 22 is similar to the diode 19 of the module 10 in that it has a first normal state in which it has a high resistance in both directions and a second state in which it has a low resistance in both directions, and it changes from its first state to its second state when a current of about 1 A flows from its emitter to its collector.
Referring now to Figure 3, a further module 30 is shown therein. This module 30 has the same terminals as the previous two modules, which tenninals are similarly referenced. The module 30 is similar to the module sown in Figure 2 in that it also utilizes an NUN transistor 22 connected between the second device terminal 16 and the second power terminal 12. However, it has a blocking diode 23 connected between the input steering terminal 13 and the first device terminal 15 rather than between the second device terminal 16 and the output steering terminal 14. The anode of the blocking diode 23 is connected to the input steering tenninal 23 and its cathode to the first device terminal 15.
Referring now to Figure a Further module 40 is shown therein. This module 40 is similar to the module 30 of Figure 3 and is similarly referenced. However, the transistor 22 and the icky blocking diode 23 are reversed.
Referring now to Figure 5, the module 50 shown therein is similar to the module 30 of Figure 3 except that it has a further NUN transistor 24 connected between the first power terminal 11, on the one hand, and the second device terminal 16 and the Output steering tenninal 14 on the other. Thus, the collector 24.2 of the transistor 24 is connected to the First power terminal 11 and the emitter 24.1 is connected to the second device terminal 16 and the output steering terminal 14. The transistor 24 is similar to the transistor 22 in that it also changes from a first normal state in which it has a high resistance to a second state in which it conducts in both direct lions, when a current of about 1.5 A is passed there through from it emitter to its collector. Further, the transistor 22 is designed so that when in its second conducting state and the current of 1.5 A is passed through it, from its collector to its emitter, it changes to a third state in which i-t presents an open-circuit.
It will be appreciated that the diode 23 and transistors 22 and 24 may be reversed, such that the diode 23 has its cathode connected to the input steering terminal 13, and the transistors 22 and 24 have their collectors connected to the output steering terminal 14.
A still further module 60 is shown in Figure 6 which is similar -to the previous modules and is similarly referenced.
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However, with this module 60 its transistor 22 is connected to the second device terminal 16 by means ox a blocking transistor 25. Thus, the emitter 22.1 of the transistor 22 is connected to the output steering terminal 14, the collector 25.2 of the transistor 25 is also connected to the output steering terminal 14 and the emitter 25.1 of the transistor 25 is connected to the second device terminal 16. The transistor 25 also changes -from its first normal state to its second conducting state together with its associated trallsistor 22.
Referring now to Figure 7, the module 70 shown therein is similar to the previous modules and is basically the module 60 together with the further transistor 24 of module 50. The transistor 24 is connected between the output steering terminal 14 and the first power terminal 11.
The module I shown in Figure 8 also has the transistors 22 and 24 with the transistor 22 connected between the second device terminal 16 and the second power terminal 12 and with the transistor 24 connected between the first power terminal 11 and the output steering terminal 14. A blocking transistor 26 is connected between the second device terminal 16 and the output steering terminal 14. The transistor 26 is also an NUN transistor with its emitter 26.1 connected to the second device terminal 16 and its collector 26.2 connected to the output steering terminal I The transistor 26 is also convertible from a normal first state to a second conducting state.
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Reference is now made to Figure 9. Shown therein designated generally by reference numeral 110 is a system For sequentially activating a number of detonators 27. Thus, the system 110 is phoned from a number of the modules 10 which are interconnected with one another and with a power supply 28. As shown, each module 10 has its device terminals 15, 16 connected to its detonator 27. The input steering terminal 13 of each module other than the first module 10.1 is connected to the output steering terminal 14 of the preceding module; and the modules alternate such that the first power terminals 11 of the first and the other odd numbered modules and the second power terminals 12 of the even numbered modules are connected to tenmi-net 28.1 of the power supply I whereas the second power terminal 12 of the first module 10.1 and the other odd numbered modules and the first power terminals 11 of the even numbered modules are connected to the other terminal 28.2 of the power supply I Further the first power tunnel 11 of the first module 10.1 is connected to its input steering terminal 13 via a , . switch 29.
'' In use the power supply 28 supplies pulses of alterna-tying polarity. Thus, when the switch 29 is closed and the first positive pulse is provided, this pulse flows through the first detonator 27.1 and the diode 19 of the first module 10.1. This I::: first diode 19 is caused to go into its second state in which it conducts in both directions and the detonator 27.1 is activated.
There is now a short circuit path between the first power , ' ~L~34L2~
terminal 11 of the second module 10.2 and its input steering Tylenol 13 Void the conducting diode 19 of the first module 10.1. Thus, the next pulse which is a negative pulse, is routed to the second module 10.2, bearing in mind that the first detonator 2~.1 has fused such that it presents an open circuit.
This second negative pulse activates the detonator 27.2 of module 10.2 and also changes the diode 19 of the second module 10.2 into its second conducting state. The process is repeated, with the next pulse, which is the third pulse, being supplied to the third module 10.3. In this manner, pulses are successively steered to successive modules, the time period between successive active-lions being dete~nined by the power supply 28.
The system 120 shown in Figure 10 is similar to that shown in Figure 9 except that modules 20 are used instead of modules 10. As with the system 110, the transistors 22 are converted into their second state in which -they conduct in both directions when the appropriate pulse supplied by the power supply 28 flows there through. It will be appreciated that the blocking diodes 21 minimize current drain through the path pro-voided by the detonators connected to the second and third modules, the transistor 22 of the third module and the further paths in parallel with the transistor 22 of the third module.
Otherwise, the operation of the system 120 is the same as that of the system 110.
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Referring now to Figure 11 and the system 135 shown therein, this system 135 is comprised of modules 30 and modules 40. The modules 40 alternate with the modules 30 as shown.
Thus, the odd numbered modules are modules 30 whereas the even numbered modules are modules 40. However, the modules 40 are "inverted" with regard to the modules 30, in that the first power terminals 11 of the modules 30 are connected to a terminal 31.1 of a power supply 31 whereas the second power terminals 12 of the modules 40 are connected to this terminal 31.1. Similarly, the second power terminals 12 of the modules 30 are connected to the other terminal 31.2 of the power supply 31 as are the first power temlinals 11 of the modules 40. With this system 135, the power supply 31 supplies only positive pulses. As with the system 110 Andy 120, the first pulse is routed to the first module via the switch 29 and causes the transistor 22 to go into its second state. The next positive pulse is routed through the second module, which is a module 40 causing its detonator 27 to be activated and causing its transistor 22 to go into its second state. The third pulse is then routed via the second module to the third module, causing its detonator to be activated and causing its transistor 22 to go into its second state.
refrying now to Figure 12, a further system 150 is shown. This system 150 is somewhat different from the other systems 110, 120 and 135, in that the modules 50 are all connect ted the same way and none are inverted. Thus, the first power terminals 11 of all the modules are connected to a terminal 32.1 ;
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o-f a power supply 32 and the second power terminals 12 ox all the modules 50 are connected Jo the other terminal 32.2 of the power supply 32. With this system 150 the power supply supplies post-live activating pulses and negative, two-stage arming pulses.
Thus when the first activating pulse is supplied it is routed to the first module 50.1 via the closed switch 29. This pulse activates the detonator 27 and causes the transistor 22 of the -first module 50.1 to go into its second conducting state. The following arming pulse then passes through the transistor 22 and its associated transistor 24. The arming pulse initially has a suitable magnitude to cause the transistor 24 to go into its second conducting state and thereafter supplies a higher current which causes the transistor 22 to go into its third open circuit state. Thus, the following activating pulse that is supplied is routed to the second module 32.2 via the transistor 24 of the first module 50.1 which is in its conducting state. This second activating pulse then activates the second detonator 27 and causes the transistor 22 of the second module 50.2 to go into its second conducting state. The process is thus repeated with the detonators 27 being successively activated.
Referring now to Figure 13, the power supply 32 is shown therein. The power supply 32 comprises a frequency shift key oscillator 34 which supplies a series of pulses to a two-bit counter 36. The oscillator 34 supplies two pulses, their dune-lion and their inter-pulse duration being determined by two variable resistors 38. The counter 36 supplies pulses to a pulse shaping and boosting module 38 which splits the pulses and supplies one pulse to a first optic coupler 40 and the other pulse to a further optic coupler 42. These optic couplers 40 and 42 drive constant current sources 44 and 46 which utilize Field effect transistors.
Although the specific examples described above utilize NUN transistors, those skilled in the art will appreciate that PUP transistors may be used solely or in combination with NUN
transistors, suitable changes being made to the blocking components.
It will be understood by those skilled in the art that the invention provides a means whereby pyrotechnic elements may be activated in a controlled sequential manner utilizing modules that are cheap to manufacture and are also robust.
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According to the invention there is provided an elect tribally operable sequential activation module for supplying an activation signal to a device which has a low resistance prior to being activated and a high resistance thereafter the module being connectable in a series with other similar modules to sequentially activate a number of the devices the module i tlCl using a first convertible element which has two terminals and in its normal first state has a high resistance in at least one direction from its first terminal -to its second terminal and which changes to a second state in which it has a low resistance in both directions when a first signal having a predetermined ----characteristic is applied across the element, the element thereafter retaining the low resistance in both directions when the first signal is removed;
a first and a second power terminal by means o-F which the module is connectable to an electrical power source for supplying the first signal and an activating signal;
a -first and a second device terminal by means of which the device is connectable to the module;
an input steering terminal, and an output steering terminal which is connectable to the input steering temlinal of a succeeding module in a series thereof with the first device terminal connected to the input steering temlinal;
the second device termirldl connected to the output steering terminal;
the second device terminal also being connected to the second terminal of the first element; and the first terminal of the first element being connected to the second power terminal.
The device may be activated by the sane signal that changes the first element, so that the first signal and active-tying signal are one signal.
The first convertible elenlent may, in its first state, have a high resistance in both directions.
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Although it has been indicated that the device has a low resistance prior to being activated and a high resistance thereafter, it will be understood by those skilled in the art that the device nay be composite in structure, comprising a unit which is activated and has a series unit that initially has the low resistance and thereafter the high resistance. Further, as the same effect will be obtained it the series unit is located in series with either the first or second device terminal the module itself may include the series unit in series with the first or second device te~linals. It will accordingly be understood that the term "device which has a low resistance prior to being activated and a high resistance thereafter" is meant to include a composite device as described above, and a device which has a low resistance also after activation in combination with a unit that could be regarded as forming part of the module.
It will be appreciated that the first element may be of any suitable material 9 form or construction. However, the apply-cant believes that the most suitable material is a semiconductor material. Further, the element may have a single junction and may, for example, be a zoner diode. The element may have two junctions, in which case it may be a bipolar transistor with only the collector and emitter being used, these forming the terminals of the element. With a zoner diode or bipolar transistor, it has been found that if a voltage is applied across the diode or transistor that is just above the breakdown voltage of the diode or transistor, and the current through the diode or ^~,~
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transistor maintained between certain predetermined levels for a sufficient period of time, then a conducting path is formed across -the diode or transistor, which remains -there after the voltage is removed. Further, this conducting path can then carry a greater current than that which formed the path without being destroyed.
Those skilled in the art will appreciate that in its basic form the module has a first power tenninal that is floe-tinge If only one module were to be connected to the power supply then there would not be a path from one power terminal to the other via a device connected to the device terminals of the module. Ivory, the modules are not used on their own but in a series, with the input steering terminal of each module in the series, except for a first nodule in the series, being connected to the output steering terminal o-f the preceding module and with their power terminals being interconnected. Further, the input steering terminal of the first module in the series is connected directly to its first power terminal or via a switch. Thus, in use, current will -flow through the input steering terminal of the first nodule to its first device terminal, through the device to the second device terminal of the first module, and through the first element of the first module in the series. This will have the effect of changing this first element into its second state, so that the voltage across the device increases, thereby active-tying it. As there is now a conducting path between the second pillager terminal and the output steering terminal of the first Jo :' ..., Jo - 6 _ ~23~
module, there Jill then be a path through the next module if it is connected in an "inverted" manner, i.e. with its first power terminal connected to the second power terminal of the first module and its second power terminal connected to the first power terminal of the first module. Thus the modules are connected with opposite polarity and are successively operated by pulses of opposite polarity.
Accordingly the invention further provides an electric gaily operable sequential activation system, which includes a plurality of modules in accordance with the invention arranged in a series with the input steering terminal of each module other than the first module being connected to the output steering terminal of the preceding module, and the first and second power terminals of the modules being interconnected.
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As indicated above the modules may alternate, with the first and second power terminals of each module being connected to the second and first power terminals, respectively of an adjacent module.
In order to ensure that only one element is changed at a time, that only one device is activated at a time and that there is not a path which will have a decreasing resistance as the number of modules in the series increases, each module may include a signal blocking means which is connected between the second device terminal and the output steering tenninal, and/or between the input steering terminal and the first device term-I,, j _ 7 _ ~23~2(3S
net, and/or between the second device terminal and the second terminal of the -first element.
The signal blocking means may be a resistor, diode or any suitable component. It may also have the same characters-tics as the first element, and may thus also be a bipolar transistor, the collector and emitter thereof being used.
If the signal blocking means is a diode, it may have its anode connected to the second device termirlal and its cathode connected -to the output steering terminal. Alternatively, the anode may be connected to the input steering terminal and the cathode may be connected to the first device terminal. Further, if the signal blacken diode is connected between the second device terminal and the first element then its anode is connected to the second device terminal and its cathode is connected to the second terminal of the first element.
If the first element is an NUN bipolar transistor, then its emitter may be connected to the second device terminal and its collector may be connected to the second power terminal.
Alternatively, it may have its collector connected to the second device terminal and its emitter to the second power terminal.
The system may have different kinds of modules. Thus the systenlnlay have two groups of modules, with modules of one group alternating with those of the other group.
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The module may include a second convertible element which has two ten~linals and in its normal First state has a high resistance in at least one direction prom its first terminal to its second terminal and which changes to a second state in which it has a low resistance in both directions when a second signal having a predetermined characteristic is applied across the eye-mint, the element thereafter having the low resistance value in both directions when the second signal is removed, the first terminal of the second element being connected to the first power tenninal and the second terminal of the second element being connected to the output steering terminal or the second device terminal, with the first element further being such that it changes into a third state when it is in its low resistance second state and a third signal having a predetermined character fistic is applied across the first element, in which third state it has a high resistance in both directions.
The second element may be substantially the same as the first element. Thus, the second elennent may also be a semiconductor, and may also have ore or two junctions. Thus, it may also be a zoner diode or a bipolar transistor. It it is an NUN transistor then it may have its collector connected to the first power terminal and its emitter connected to the output steering terminal or the second device terminal.
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Tulsa skilled in the art will appreciate that when a transistor is converted into its conducting state as described above and a current of sufficient magnitude is passed there-through for long enough, it will be damaged to such an extent that it forms an open circuit.
With modules having first and second elements it is possible to form a system without "inverting" any modules. Thus all the first power terminals are connected together and all the second power terminals are connected together. Then, the modules are supplied with a series of pulses, there being a positive pulse which changes the first element of the first module into its second state and activates the -first device, a subsequent pulse of negative polarity which changes the second element of the first module into its second state and then increases in magnitude to change the first element of the first module into its third non-conducting state, with the sequence repeating.
Each successive positive pulse causes the first element of the next module in the series to change into its second state and the device associated with that module to be activated.
The invention accordingly extends further to a power source for an electrically operable sequential activation system, which supplies a repeating group of pulses, a first pulse in each group being of a predete~ined polarity and a second pulse in each group being of the opposite polarity and which supplies second pulses that have an initial predetermined magnitude and thereafter have a greater magnitude.
:
i - 10~
The invention is now described by way ox examples with reference to the accompanying drawings, in which:-Figures 1 to 8 show different electrically operable sequent trial activation modules in accordance with the invention; and Figures 9 to 12 show sequential activation systems in accord dance with the invention; and Figure 13 shows a power source in accordance with the invent lion.
Referring to Figure 1, shown therein designated generally by reference numeral 10 is an electrically operable sequential activation module -For supplying an activation signal to a detonator (not shown in Figure 1) which has a low resistance prior -to being activated and a high resistance thereafter. As is discussed herein below, the module 10 is connected in a series with other similar modules to form an activation system.
Thus, as shown in Figure 1, the module 10 has a first power Tylenol 11, a second power terminal 12, an input steering temlinal 13, an output steering tenninal 14, a first device terminal 15 and a second device terminal 16. The input steering tenninal 13 and the first device temlinal 15 are directly electrically connected by means of a conducting link 17.
Similarly, the second device tenninal 16 and the output steering terminal 14 are directly connected by means o-F a link 18. The second device terlninal 16 is also connected to the second power . . I.
, 3~2~)~
terminal 12 by means of d diode 19. The anode of the diode 19 is connected to the second device terminal 16 and the cathode is connected to the second power tenninal 12. It will be noted, that as the second device terminal 16 and the output steering terminal 14 are directly connected, the diode 19 is also, in effect, connected between the output steering terminal 14 and the second power terminal 12. The diode 19 is such that in its nodal First state it has a high resistance in the direction from the second power terminal 12 to the second device terminal 16 or output steering terminal 14; and a low resistance in the opposite direction. However, the diode 19 is such that when a current of a predetermined magnitude (in the order of 1 amp) is passed through the diode in its forward direction, for a suitable period of time, a conducting path is formed across the junction of the diode 19 such that it also has a low resistance from the second power terminal to the second device terminal 16.
Referring to Figure 23 a module 20 is shown therein which is similar to the module 10 of Figure 1. Thus, the module also has the various terminals designated in Figure 1, which terminals are similarly referenced. The input steering terminal 13 and the first device terminal 15 are also directly connected by means of the link 17. However, there is a blocking diode 21 between the second device terminal 16 and the output steering terminal 14, with its anode being connected to the second device terminal 16 and its cathode to the output steering terminal 14.
Instead of the diode 19 being connected between the second device terminal 16 and the second power terminal 12 as in the module 10, .
the module 20 has an NO transistor 22 connected there between.
The emitter 22.1 of the transistor 22 is connected to the second device -terminal 16 and the collector 22.2 is connected to the second power terminal 12. The base of the transistor 22 is not ~tilised and is left floating. The transistor 22 is similar to the diode 19 of the module 10 in that it has a first normal state in which it has a high resistance in both directions and a second state in which it has a low resistance in both directions, and it changes from its first state to its second state when a current of about 1 A flows from its emitter to its collector.
Referring now to Figure 3, a further module 30 is shown therein. This module 30 has the same terminals as the previous two modules, which tenninals are similarly referenced. The module 30 is similar to the module sown in Figure 2 in that it also utilizes an NUN transistor 22 connected between the second device terminal 16 and the second power terminal 12. However, it has a blocking diode 23 connected between the input steering terminal 13 and the first device terminal 15 rather than between the second device terminal 16 and the output steering terminal 14. The anode of the blocking diode 23 is connected to the input steering tenninal 23 and its cathode to the first device terminal 15.
Referring now to Figure a Further module 40 is shown therein. This module 40 is similar to the module 30 of Figure 3 and is similarly referenced. However, the transistor 22 and the icky blocking diode 23 are reversed.
Referring now to Figure 5, the module 50 shown therein is similar to the module 30 of Figure 3 except that it has a further NUN transistor 24 connected between the first power terminal 11, on the one hand, and the second device terminal 16 and the Output steering tenninal 14 on the other. Thus, the collector 24.2 of the transistor 24 is connected to the First power terminal 11 and the emitter 24.1 is connected to the second device terminal 16 and the output steering terminal 14. The transistor 24 is similar to the transistor 22 in that it also changes from a first normal state in which it has a high resistance to a second state in which it conducts in both direct lions, when a current of about 1.5 A is passed there through from it emitter to its collector. Further, the transistor 22 is designed so that when in its second conducting state and the current of 1.5 A is passed through it, from its collector to its emitter, it changes to a third state in which i-t presents an open-circuit.
It will be appreciated that the diode 23 and transistors 22 and 24 may be reversed, such that the diode 23 has its cathode connected to the input steering terminal 13, and the transistors 22 and 24 have their collectors connected to the output steering terminal 14.
A still further module 60 is shown in Figure 6 which is similar -to the previous modules and is similarly referenced.
Jo - 14 - ~L~3~0~
However, with this module 60 its transistor 22 is connected to the second device terminal 16 by means ox a blocking transistor 25. Thus, the emitter 22.1 of the transistor 22 is connected to the output steering terminal 14, the collector 25.2 of the transistor 25 is also connected to the output steering terminal 14 and the emitter 25.1 of the transistor 25 is connected to the second device terminal 16. The transistor 25 also changes -from its first normal state to its second conducting state together with its associated trallsistor 22.
Referring now to Figure 7, the module 70 shown therein is similar to the previous modules and is basically the module 60 together with the further transistor 24 of module 50. The transistor 24 is connected between the output steering terminal 14 and the first power terminal 11.
The module I shown in Figure 8 also has the transistors 22 and 24 with the transistor 22 connected between the second device terminal 16 and the second power terminal 12 and with the transistor 24 connected between the first power terminal 11 and the output steering terminal 14. A blocking transistor 26 is connected between the second device terminal 16 and the output steering terminal 14. The transistor 26 is also an NUN transistor with its emitter 26.1 connected to the second device terminal 16 and its collector 26.2 connected to the output steering terminal I The transistor 26 is also convertible from a normal first state to a second conducting state.
- 15 - Lo 3 2 I
Reference is now made to Figure 9. Shown therein designated generally by reference numeral 110 is a system For sequentially activating a number of detonators 27. Thus, the system 110 is phoned from a number of the modules 10 which are interconnected with one another and with a power supply 28. As shown, each module 10 has its device terminals 15, 16 connected to its detonator 27. The input steering terminal 13 of each module other than the first module 10.1 is connected to the output steering terminal 14 of the preceding module; and the modules alternate such that the first power terminals 11 of the first and the other odd numbered modules and the second power terminals 12 of the even numbered modules are connected to tenmi-net 28.1 of the power supply I whereas the second power terminal 12 of the first module 10.1 and the other odd numbered modules and the first power terminals 11 of the even numbered modules are connected to the other terminal 28.2 of the power supply I Further the first power tunnel 11 of the first module 10.1 is connected to its input steering terminal 13 via a , . switch 29.
'' In use the power supply 28 supplies pulses of alterna-tying polarity. Thus, when the switch 29 is closed and the first positive pulse is provided, this pulse flows through the first detonator 27.1 and the diode 19 of the first module 10.1. This I::: first diode 19 is caused to go into its second state in which it conducts in both directions and the detonator 27.1 is activated.
There is now a short circuit path between the first power , ' ~L~34L2~
terminal 11 of the second module 10.2 and its input steering Tylenol 13 Void the conducting diode 19 of the first module 10.1. Thus, the next pulse which is a negative pulse, is routed to the second module 10.2, bearing in mind that the first detonator 2~.1 has fused such that it presents an open circuit.
This second negative pulse activates the detonator 27.2 of module 10.2 and also changes the diode 19 of the second module 10.2 into its second conducting state. The process is repeated, with the next pulse, which is the third pulse, being supplied to the third module 10.3. In this manner, pulses are successively steered to successive modules, the time period between successive active-lions being dete~nined by the power supply 28.
The system 120 shown in Figure 10 is similar to that shown in Figure 9 except that modules 20 are used instead of modules 10. As with the system 110, the transistors 22 are converted into their second state in which -they conduct in both directions when the appropriate pulse supplied by the power supply 28 flows there through. It will be appreciated that the blocking diodes 21 minimize current drain through the path pro-voided by the detonators connected to the second and third modules, the transistor 22 of the third module and the further paths in parallel with the transistor 22 of the third module.
Otherwise, the operation of the system 120 is the same as that of the system 110.
j, Jo :~3~20S
Referring now to Figure 11 and the system 135 shown therein, this system 135 is comprised of modules 30 and modules 40. The modules 40 alternate with the modules 30 as shown.
Thus, the odd numbered modules are modules 30 whereas the even numbered modules are modules 40. However, the modules 40 are "inverted" with regard to the modules 30, in that the first power terminals 11 of the modules 30 are connected to a terminal 31.1 of a power supply 31 whereas the second power terminals 12 of the modules 40 are connected to this terminal 31.1. Similarly, the second power terminals 12 of the modules 30 are connected to the other terminal 31.2 of the power supply 31 as are the first power temlinals 11 of the modules 40. With this system 135, the power supply 31 supplies only positive pulses. As with the system 110 Andy 120, the first pulse is routed to the first module via the switch 29 and causes the transistor 22 to go into its second state. The next positive pulse is routed through the second module, which is a module 40 causing its detonator 27 to be activated and causing its transistor 22 to go into its second state. The third pulse is then routed via the second module to the third module, causing its detonator to be activated and causing its transistor 22 to go into its second state.
refrying now to Figure 12, a further system 150 is shown. This system 150 is somewhat different from the other systems 110, 120 and 135, in that the modules 50 are all connect ted the same way and none are inverted. Thus, the first power terminals 11 of all the modules are connected to a terminal 32.1 ;
. .: i, ' ;
:
~23~2~)~
o-f a power supply 32 and the second power terminals 12 ox all the modules 50 are connected Jo the other terminal 32.2 of the power supply 32. With this system 150 the power supply supplies post-live activating pulses and negative, two-stage arming pulses.
Thus when the first activating pulse is supplied it is routed to the first module 50.1 via the closed switch 29. This pulse activates the detonator 27 and causes the transistor 22 of the -first module 50.1 to go into its second conducting state. The following arming pulse then passes through the transistor 22 and its associated transistor 24. The arming pulse initially has a suitable magnitude to cause the transistor 24 to go into its second conducting state and thereafter supplies a higher current which causes the transistor 22 to go into its third open circuit state. Thus, the following activating pulse that is supplied is routed to the second module 32.2 via the transistor 24 of the first module 50.1 which is in its conducting state. This second activating pulse then activates the second detonator 27 and causes the transistor 22 of the second module 50.2 to go into its second conducting state. The process is thus repeated with the detonators 27 being successively activated.
Referring now to Figure 13, the power supply 32 is shown therein. The power supply 32 comprises a frequency shift key oscillator 34 which supplies a series of pulses to a two-bit counter 36. The oscillator 34 supplies two pulses, their dune-lion and their inter-pulse duration being determined by two variable resistors 38. The counter 36 supplies pulses to a pulse shaping and boosting module 38 which splits the pulses and supplies one pulse to a first optic coupler 40 and the other pulse to a further optic coupler 42. These optic couplers 40 and 42 drive constant current sources 44 and 46 which utilize Field effect transistors.
Although the specific examples described above utilize NUN transistors, those skilled in the art will appreciate that PUP transistors may be used solely or in combination with NUN
transistors, suitable changes being made to the blocking components.
It will be understood by those skilled in the art that the invention provides a means whereby pyrotechnic elements may be activated in a controlled sequential manner utilizing modules that are cheap to manufacture and are also robust.
Jo '' ., :
Claims (32)
1. An electrically operable sequential activation module for supplying an activation signal to a device which has a low resis-tance prior to being activated and a high resistance thereafter, the module being connectable in a series with other similar modules to sequentially activate a number of the devices, the module including a first convertible element which has two terminals and in its normal first state has a high resistance in at least one direction from its first terminal to its second terminal and which changes to a second state in which it has a low resistance in both directions when a first signal having a predetermined characteristic is applied across the element, the element thereafter having the low resistance value in both directions when the first signal is removed;
a first and a second power terminal by means of which the module is connectable to an electrical power source For supplying the first signal and an activating signal;
a first and a second device terminal by means of which the device is connectable to the module;
an input steering terminal, and;
an output steering terminal which is connectable to the input steering terminal of a preceding module in a series thereof;
with the first device terminal connected to the input stee-ring terminal;
the second device terminal connected to the output steering terminal;
the second device terminal also being connected to the second terminal of the first element; and the first terminal of the first element being connected to the second power terminal.
a first and a second power terminal by means of which the module is connectable to an electrical power source For supplying the first signal and an activating signal;
a first and a second device terminal by means of which the device is connectable to the module;
an input steering terminal, and;
an output steering terminal which is connectable to the input steering terminal of a preceding module in a series thereof;
with the first device terminal connected to the input stee-ring terminal;
the second device terminal connected to the output steering terminal;
the second device terminal also being connected to the second terminal of the first element; and the first terminal of the first element being connected to the second power terminal.
2. The module as claimed in Claim 1, which includes a signal blocking leans which is connected between the second device terminal and the output steering terminal.
3. The module as claimed in Claim 1, which includes a signal blocking means which is connected between the input steering terminal and the first device terminal.
4. The module as claimed in Claim 1, in which the first element is of a semiconductor material.
5. The module as claimed in Claim 4, in which the first element has a single junction.
6. The module as claimed in Claim 4, in which the first element has two junctions.
7. The module as claimed in claim 6, in which the first element is a bi-polar transistor its collector and emitter comprising its terminals.
8. The module as claimed in Claim 7, in which the emitter of the transistor is connected to the second device terminal and the collector of the transistor is connected to the second power terminal.
9. The module as claimed in claim 2, in which the signal blocking means is a diode, which has its anode connected to the second device terminal and its cathode connected to the output steering terminal
10. The module as claimed in Claim 3, in which the signal blocking means is a diode, which has its anode connected to the input steering terminal and its cathode connected to the first device terminal.
11. The module as claimed in claim 1, in which the first element is a bi-polar transistor that has its emitter connected to the second power terminal and its collector connected to the second device terminal.
12. The module as claimed in claim 1, which includes a second convertible element which has two terminals and in its normal first state has a high resistance in at least one direction from its first terminal to its second terminal and which changes to a second state in which it has a low resistance in both directions, when a second signal having a predetermined characteristic is applied across the element, the element thereafter having the low resistance value in both directions when the second signal is removed, the first terminal of the second element being connected to the first power terminal and the second terminal of the second element being connected to the output steering terminal, with the first element further being such that it changes into a third state when it is in its low resistance second state and a third signal having a predetermined characteristic is applied across the first element, in which third state it has a high resistance in both directions.
13. The module as claimed in Claim 1, which includes a second convertible element which has two terminals and in its normal first state has a high resistance in at least one direction from its first terminal to its second terminal and which changes to a second state in which it has a low resistance in both directions when a second signal having a predetermined characteristic is applied across the element, the element thereafter having the low resistance value in both directions when the second signal is removed, the first terminal of the second element being connected to the first power terminal and the second terminal of the second element being connected to the second device terminal, with the first element further being such that it changes into a third state when it is in its low resistance second state and a third signal having a predetermined characteristic is applied across the first element, in which third state it has a high resistance in both directions.
14. The module as claimed in Claim 12, in which the first ele-ment is a bi-polar transistor, the emitter and collector of which comprise its terminals.
15. The module as claimed in Claim 14, in which the emitter of the first element is connected to the second device terminal and the collector thereof is connected to the second power terminal.
16. The module as claimed in claim 14, in which the second element is also a bi-polar transistor, the collector of which is connected to the first power terminal and the emitter of which is connected to the second device terminal or the output steering terminal.
17. The module as claimed in Claim 12, which includes a signal blocking means which is connected between the second device terminal and the output steering terminal.
18. The module as claimed in Claim 12, which includes a signal blocking means which is connected between the input steering terminal and the first device terminal.
19. The module as claimed in Claim 1, in which the first element is connected to the second device terminal via a signal blocking means.
20. An electrically operable sequential activation system, which includes a plurality of modules as claimed in Claim 1 arranged in a series with the input steering terminal of each module other than the first module being connected to the output steering terminal of the preceding module, and the first and second power terminals of the modules being interconnected.
21. An electrically operable sequential activation system, which includes a plurality of modules as claimed in Claim 1, arranged in a series with the input steering terminal of each module other than the first module being connected to the output steering terminal of the preceding module, and the modules alternating with the first and second power terminals of each module being connected to the second and first power terminals, respectively of an adjacent module.
22. An electrically operable sequential activation system, which includes a first group of modules as claimed in Claim 1, and a second group of modules as claimed in Claim 11 arranged in a series, with the input steering terminal of each module other than the first module being connected to the output steering terminal of the preceding module, and the modules of the first group alternating with the modules of the second group, with the first and second power terminals of each module of the first group being connected to the second and first power terminals, respectively, of an adjacent module of the second group.
23. An electrically operable sequential activation system, which includes a plurality of modules as claimed in Claim 12 arranged in a series with the input steering terminal of each module other than the first module being connected to the output steering terminal of the preceding module, and the first and second power terminals of each module being connected to the first and second power terminals, respectively of an adjacent module.
24. An electrically operable sequential activation system, which includes a plurality of modules as claimed in Claim 13, arranged in a series with the input steering terminal of each module other than the first module being connected to the output steering terminal of the preceding module, and the first and second power terminals of each module being connected to the first and second power terminals, respectively of an adjacent module.
25. An electrically operable sequential activation system, which includes a first group of modules as claimed in Claim 18 and a second group of modules as claimed in Claim 1 arranged in a series, with the input steering terminal of each module other than the first module being connected to the output steering terminal of the preceding module, and the modules of the first group alternating with the modules of the second group, with the first and second power terminals of each module of the first group being connected to the second and first power terminals, respectively, of an adjacent module of the second group.
26. The system as claimed in Claim 21, with includes a plurality of devices, there being a device connected to the first and second device terminals of each module.
27. The system as claimed in Claim 21, which includes an electrical power source connected to the first and second power terminals of a last module in the series, the power source being such that it supplies a series of first signals and activating signals that are pulses of alternating polarity.
28. The system as claimed in Claim 22, which includes an electrical power source connected to the first and second power terminals of a last module in the series, the power source being such that it supplies a series of first signals and activating signals that are pulses of the same polarity.
29. The system as claimed in Claim 22, which includes an electrical power source connected to the first and second power terminals of a last module in the series, the power source being such that it supplies a series of first signals and activating signals that are of a constant DC value.
30. The system as claimed in Claim 24, which includes an electrical power source connected to the first and second power terminals of a last module in the series, the power source being such that it repeatedly supplies a first signal, an activating signal, a second signal, and a third signal, the first and acti-vating signals being pulses of a predetermined polarity and the second and third signals being pulses of the opposite polarity.
31. The system as claimed in Claim 30, in which the power source supplies second signals that have a magnitude that is less than the magnitude of the third signals.
32. The system as claimed in claim 26, in which the devices are detonators.
Applications Claiming Priority (4)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| ZA841459 | 1984-02-28 | ||
| ZA84/1459 | 1984-02-28 | ||
| ZA846195A ZA846195B (en) | 1983-10-05 | 1984-08-09 | Electrical sequential firing system |
| ZA84/6195 | 1984-08-09 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1234205A true CA1234205A (en) | 1988-03-15 |
Family
ID=27135280
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000469085A Expired CA1234205A (en) | 1984-02-28 | 1984-11-30 | Electrical sequential firing system |
Country Status (1)
| Country | Link |
|---|---|
| CA (1) | CA1234205A (en) |
-
1984
- 1984-11-30 CA CA000469085A patent/CA1234205A/en not_active Expired
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