U.S. patent application number 10/495848 was filed with the patent office on 2005-01-27 for installation for programmable pyrotechnic shot firing.
Invention is credited to Bernard, Thierry.
Application Number | 20050016407 10/495848 |
Document ID | / |
Family ID | 8869519 |
Filed Date | 2005-01-27 |
United States Patent
Application |
20050016407 |
Kind Code |
A1 |
Bernard, Thierry |
January 27, 2005 |
Installation for programmable pyrotechnic shot firing
Abstract
Programmable pyrotechnical firing installation comprising a
programming and firing control unit (8), a programming and control
line comprising two conductor wires (6a, 6b) and a plurality of
electronic detonators (4) mounted in parallel on this two-wire
line, wherein the programming unit (8) comprises means (9, 10) for
establishing a continuous voltage between the two wires (6a, 6b),
means (9, 10) for producing pulses of this voltage so as to form
coded signals, and means (11, 9) for reading the current variations
existing on the two-wire line, wherein every detonator comprises an
electronic module (12) that has means (14, 17) suitable for
producing, in response to certain of the coded signals of the
programming unit (8), current pulses in the two-wire line (6a, 6b)
for forming coded signals.
Inventors: |
Bernard, Thierry; (Nice,
FR) |
Correspondence
Address: |
Ronald R Santucci
Frommer Lawrence & Haug
745 Fifth Avenue
New York
NY
10151
US
|
Family ID: |
8869519 |
Appl. No.: |
10/495848 |
Filed: |
August 27, 2004 |
PCT Filed: |
November 14, 2002 |
PCT NO: |
PCT/FR02/03891 |
Current U.S.
Class: |
102/200 ;
361/248 |
Current CPC
Class: |
F42D 1/05 20130101 |
Class at
Publication: |
102/200 ;
361/248 |
International
Class: |
F42C 001/00 |
Foreign Application Data
Date |
Code |
Application Number |
Nov 19, 2001 |
FR |
01/14916 |
Claims
1. A programmable pyrotechnical firing installation comprising a
programming and firing control unit (8), a programming and control
line comprising two conductor wires (6a, 6b) and a plurality of
electronic detonators (4) mounted in parallel on this two-wire
line, wherein the programming unit (8) comprises means (9, 10) for
establishing a continuous voltage between the two wires (6a, 6b),
means (9, 10) for producing pulses of this voltage so as to form
coded signals and means (11, 9) for reading the current variations
existing on the two-wire line and in that every detonator comprises
an electronic module (12) that has means (14, 17) suitable for
producing, in response to certain of the coded signals of the
programming unit (8), current pulses in the two-wire line (6a, 6b)
for forming coded signals.
2. A firing installation according to claim 1, wherein every
electronic detonator module (12) comprises a switch (18) of the
two-wire line (6a, 6b), which normally is open and is closed in
response to a signal emitted by the programming unit (8).
Description
[0001] In mines and quarries the breaking of rocks is typically
carried out by means of explosives.
[0002] A firing program consists of making a plurality of
drill-holes in the rock, which are filled with explosives with, for
every drill-hole, a detonator that permits the firing. Some of
these detonators are electronically controlled, which makes it
possible to program the setting off of the explosions according to
a predetermined firing plan.
[0003] The execution of a firing plan consists, therefore, after
having arranged all the detonators in the drill-holes that have
been made and connecting them to a control unit, of identifying
every detonator by a serial number and applying to it a delay time
which will determine the ignition of the charge in relation to a
general firing signal.
[0004] The present invention relates to such a programmable
pyrotechnical firing installation, in which all the detonators are
connected to the control unit by wires.
[0005] Conventionally, an electronic detonator comprises a
pyrotechnical percussion cap, an energy reserve, an electronic
pilot and two electrical conductors that connect the electronic
pilot to a firing line which runs over the ground from a central
programming and control unit. The electronic pilot comprises an
on-board microprocessor by means of which communication can be
established between the detonator and the central unit. The
microprocessor is programmed or programmable so as to be able to
receive requests issued in the firing line by the central unit and
to respond to these requests either in the direction of the central
unit or in the direction of the energy reserve, which it will
release with a specific time delay when the firing order has been
received from the central unit. The programming of the on-board
microprocessor in the electronic pilot of the detonator can be
carried out a priori before its positioning in the firing field or,
as is the case for the invention, a posteriori after it has been
put into position. The firing line on the ground also serves to
provide the electrical energy required for filling the energy
reserve, which takes place just before the firing in order to
comply with the safety requirements that demand that the detonators
must be inactive up to the last moment.
[0006] It must be borne in mind that a firing line may have a
length of about a kilometre. For this reason, with the current
installations it is relatively simple to transmit from the control
unit signals to the address of every detonator, however far this
may be removed from the control unit, since the required energy to
be provided for these signals so that they will reach their target
is controlled totally from the control unit. On the other hand, a
detonator has very little on-board energy and if one wants it to be
able to respond to the central unit, it will be noted that the
limited power of the signals which it emits suffers a strong
attenuation that may make them inaudible by the central unit if the
detonator-emitter is far away from same on the firing line.
[0007] The present invention provides a solution to this
bi-directional communication problem between a central unit and
each one of the detonators of a firing line, a simple and
economical solution.
[0008] To this end, the invention relates to a programmable
pyrotechnical firing installation comprising a programming and
control unit for the firing, a programming and control line
comprising two conductor wires and a plurality of electronic
detonators mounted in parallel on this two-wire line, wherein the
programming unit comprises means for establishing a continuous
voltage between the two wires, means for producing pulses of this
voltage so as to form coded signals and means for reading the
current variations existing on the two-wire line and wherein every
detonator comprises an electronic module that, in response to
certain of the coded signals of the programming unit corresponding
to requests from same, can produce current pulses in the two-wire
line for forming coded signals.
[0009] In other words, when a detonator, whatever its position on
the firing line, must respond to a request of the central unit, it
will produce in the filar firing line excess current peaks, for
example by closing the line on a calibrated resistor within a given
time and this in dependence on a pulses program corresponding to a
code generated by the on-board microprocessor, which excess current
peaks are immediately detectable by the central unit, which by
means of a resistor will convert them into a modulated voltage that
can be interpreted by its microprocessor, this forming the response
of the detonator in question to the request of this central
unit.
[0010] Other characteristics and advantages of the invention will
be noted from the description given below by way of non-limitative
example, of an exemplified embodiment.
[0011] Reference will be made to the attached drawings,
wherein:
[0012] FIG. 1 is a diagram illustrating a pyrotechnical firing
installation,
[0013] FIG. 2 illustrates diagrammatically a central programming
and control unit of the installation,
[0014] FIG. 3 is a functional diagram of that part of the
electronic pilot of every detonator involved in the dialogue with
the central programming and control unit.
[0015] To carry out a firing program, holes 1 are drilled in a rock
2 from, for example, the ground 3. In each of these drill-holes 1,
detonators 4 and explosive charges 5 are placed, every detonator 4
being connected to firing line 6 on the ground by conductors 7. A
central programming and control unit is shown at 8, connected to
the firing line 6.
[0016] This unit 8, see FIG. 2, comprises a microprocessor 9 which
acts on a device 10 for the supply of a continuous voltage between
the two wires 6a, 6b of the line 6 and which permits inserting into
this continuous voltage drop sequences so as to form slots
corresponding to any type of binary code of a signal. Furthermore,
the central unit 8 is provided with a device 11 for converting into
voltage the current circulating on the line 6a, 6b in order to
produce variations of this current that can be understood by the
microprocessor 9.
[0017] The electronic pilot 12 of the detonator illustrated
diagrammatically and partially in FIG. 3, comprises a voltage
regulator 13, the input of which is connected to the line 6a, and
the output to an on-board microprocessor 14, in order to form a
power supply of this microprocessor 14 increased by a capacitor 15
that permits smoothing the drops in voltage in the line 6. This
pilot 12 also comprises a circuit 16 for detecting codes carried by
the line 6, the input of which is also connected to the line 6a and
the outlput of which is directed towards the microprocessor 14.
Between the lines 6a and 6b the electronic pilot 12 has a
voltage-drawing circuit 17, for example a transistor and a
resistor, controlled by the microprocessor 14. Finally, the
microprocessor 14 controls a switch 18 of the line 6a, in a manner
as will be explained below.
[0018] Each one of the detonators 1 is connected to the two-wire
line 6a, 6b parallel to same at the point A, B (FIG. 3). In
reality, four wires 19, 20, 21, 22 come from this electronic pilot
12, which form the conductors 7 of FIG. 1. The wires 19 and 20
permit connecting the pilot to the wires 6a and 6b of the firing
line. The line 6a has a section 23 inside the pilot 12, which
comprises the switch 18 and which comes out of the pilot by way of
the line 21 which becomes 6a at the level of the ground. In the
same manner the line 6b has a section 24 inside the pilot, which by
way of the conductor 22 comes out of the drill-hole to form the
wire 6b of the firing line at the level of the ground. At the time
when the detonators are positioned in the drill-holes, the switch
18 is open. The electronic pilots are connected the one following
the other. Understood under this mounting method is that the first
detonator connected to the unit 8 is mounted in series on the line
6a, 6b when the switch 18 is open. When the switch 18 is closed,
this detonator is mounted in parallel with the next one on the line
6a, 6b.
[0019] When the firing line has been realised, the central unit 8
establishes a voltage of, for example, 24 or 48 volt at the
terminals of the conductors 6a, 6b. This voltage, regulated by the
device 13, constitutes the power supply of the processor 14 as well
as the charge of the capacitor 15. By cutting this voltage by means
of the device 10, the microprocessor 9 of the central unit 8
transmits to the pilot 12 a serial number recorded by the
microprocessor 14, and a certain delay time. The operating sequence
of the microprocessor 9 may then comprise a request (a binary
signal on the voltage of the line 6) to which the microprocessor 14
will respond by acting on the current-drawing circuit 17 to create
excess voltage peaks which, converted by the device 11, will be
assimilated as a response to the request by the microprocessor 9.
The last order transmitted by the microprocessor 9 to the onboard
microprocessor 14 will be to close the switch 18. At this moment,
the pilot of the next detonator is in the same state with regard to
the central unit 8 as the preceding pilot and the programming
sequence can recommence.
[0020] When all the detonators have been programmed in this manner,
the firing installation is ready to operate. The microprocessor 9
may comprise in its program other stages and other requests
concerning the detonators. It will then transmit a general order to
all the detonators to proceed with the charging of the energy
reserve, not illustrated in the figures, possibly followed by a
verification of the state of this reserve, and will finally
transmit to all the detonators a firing signal.
* * * * *