FR2738626A1 - FIRE-FIGHTING CIRCUIT FOR MULTI-CARTRIDGE AMMUNITION - Google Patents

Abstract

In this circuit, each cartridge is equipped with a detonator (R1 to Rn) which via a switch (C1 to Cn, L1 to Ln) is capable of being selectively connected to the terminals (B1, B2) d a source of electrical energy for its firing according to a predetermined firing schedule. According to the invention, the detonators (R1 to Rn) are connected in a matrix (M; M1) comprising column conductors (c1 to cn) and row conductors (l1 to In) connected respectively by one of their ends at the terminals (B1, B2) of the source through the switches (C1 to Cn, L1 to Ln). In addition, at each intersection (IN) of a row conductor (l1 to In) and a column conductor (c1 to cn), these conductors are connected together by the series connection of a detonator (R1 to Rn) and a component (D1 to Dn) with unidirectional current conduction. Application in particular to decoy launchers.

Description

The present invention relates to a device for

  firing for multiple cartridge ammunition.

  One of the applications of multiple-cartridge ammunition can be found in aircraft self-protection techniques. These techniques use decoy launchers often equipped with a number of loaders including themselves ammunition composed of a large number of cartridges that can be fired in turn with the aid of an igniter or from a detonator to

online order.

  Such equipment makes it possible to drop the aircraft, for example radar jamming flakes or pyrotechnic elements which, by emitting infrared energy, disturb the tracking tracking devices.

by the IRs.

  A shooting device of this kind has been described in French Patent No. 2,611,883 in the name of the Applicant. We can refer to this document for more details on the construction and operation of these

equipment.

  Although the invention finds particular application in these equipment, it should be noted from the outset that it is in no way limited and that it can be implemented advantageously in all cases where it is necessary to selectively firing a large number of cartridges making up a system or ammunition, each cartridge being able to be ignited by means of an igniter or

  an electrically operated detonator.

  This being the case, FIG. 1 shows appended drawings of a known firing control circuit for a pyrotechnic equipment such as a decoy launching device comprising here two ammunition or magazines each composed of 24 cartridges that can be fired by individual detonators rated from R1 to R24. We see that the circuit is connected to a voltage source, 28 volts for example,

  via terminals B1 and B2.

  The positive terminal B1 is connected to a current generator GC which makes it possible to impose on the circuit a setpoint current i and to trigger the firing operations in

  taking into account the time parameters t required.

  Each charger or ammunition C1, C2 comprises a static general switch, II, I2, connected to the current generator GC and to a parallel connection of the 24 detonators R1 to R24, themselves connected in series with transistorized switches, resp. K1 to K24. The other terminal of this parallel connection is connected to terminal B2 of the voltage source. The switches K1 to K24 of each loader C1, C2 are controlled by electronics of

ED decoding.

  To control a detonator of a charger, one proceeds

as follows.

  The charger concerned is selected from the chargers

  C1, C2 by operating the switch Il, I2 corresponding.

  Then, using the decoding electronics of this charger, the detonator path to be tripped is selected and the switch K1 to K24 concerned is closed. Then, the generator GC is controlled by the application of the current instructions i and time t. For example, one can send a current of 6 A by a pulse of 10 ms duration. All detonators can thus be selectively switched on in

  according to a predetermined fire program.

  This known firing control circuit presents

  the disadvantage of requiring a switch by detonator.

  In addition, the detonators of a typical charger currently manufactured having 24 cartridges, must be connected in the circuit by means of a connector with 25 connection points each (24 for the positive terminal (here the connection to the switch It or I2 respectively) and a common point for the return to earth by the terminal B2 which represents

important wiring.

  Another disadvantage of this known circuit lies in the fact that a given detonator can be turned on unexpectedly if its corresponding single switch is closed by a circuit failure. On the other hand, if the 28 Volt supply voltage is improperly applied at any point in the circuit, it will result in an accidental firing of one or more

cartridges.

  The object of the invention is to provide a firing circuit for ammunition with multiple cartridges, in particular for a decoy looter used for an aircraft, by means of which the disadvantages of the prior art can be avoided. In addition, the circuit targeted by the invention makes it possible to simplify considerably the necessary wiring, to increase the reliability of the firing control and to further the miniaturization of a decoy launching device by a saving of

components constituting the circuit.

  The invention therefore relates to a firing circuit for ammunition with multiple cartridges, each cartridge being equipped with a detonator which, via a switch, is capable of being selectively connected to the terminals of a source of fuse. electrical energy for firing it according to a predetermined firing program, characterized in that said detonators are connected in a matrix comprising column conductors and line conductors respectively connected by one of their ends to said terminals through said switches and in that at each intersection of a line conductor and a column conductor, these conductors are connected to each other by series connection of a detonator and a conduction component

unidirectional current.

  Thanks to these characteristics, the firing circuit can be built with a simpler wiring, a reduced number of switches and a control circuit of these switches comprising a number of components also reduced. Other features and advantages of the invention

  will appear in the following description,

  given only by way of example and with reference to the accompanying drawings in which: - Figure 1 already described is an electrical diagram of a firing circuit according to the prior art; FIG. 2 is an electrical diagram of a firing circuit according to the invention; and - Figures 3 and 4 are diagrams of two variants

  embodiment of the firing circuit according to the invention.

  It should be noted that in the diagrams of the figures, the pyrotechnic safety which is carried out by specific external components has not been taken into account.

  not part of the present invention.

  In FIG. 2, it can be seen that, like the prior circuit of FIG. 1, the firing circuit according to the invention is powered by a voltage source at 28.

  volts for example, through terminals B1 and B2.

  The current generator GC is connected in the same way between the positive terminal B1 of this source and the circuit

well said.

  According to the invention, it comprises a matrix M of a plurality of line conductors 11 to 11 intersecting with a plurality of column conductors

cl to cn.

  The column conductors C1 to cn are respectively connected to the current generator GC, through column switches C1 to Cn preferably made to

  using switching transistors.

  The line conductors 11 to in are respectively connected to the negative terminal B2 of the current source, through switches L1 to Ln formed preferably

  also switching transistors.

  At each intersection IN of a line conductor and a column conductor is provided the series connection of a detonator, R1 to Rn respectively, and a component, D1 to Dn respectively, of electrical conduction

  unidirectional such as a non-return diode, for example.

  These components are intended to block the parasitic current paths that would be formed in their absence, by the selection of a detonator among the detonators of

  the matrix M for ignition.

  To control such a detonator, for example the detonator R5, it is first necessary to close the switch C2, then the switch L2 and then to control the current generator GC by applying the appropriate reference signals i and t. For example, the current can

  be 6 A and the duration of the pulse can be 10 ms.

  The main advantage of the invention arises directly from a careful comparison of FIGS. 1 and 2. Whereas, as already indicated above, in the assembly of FIG. 1, it is necessary to have, for a number of n detonators, of a connector of n + 1 connection points in order to be able to connect them in the circuit (that is to say n for their positive terminal and a common terminal for their connection to the ground. the invention, if n is the number of detonators, it suffices to provide only c + 1 connections, c being the number of detonators per column and 1 the number of detonators per line, for example if n = 25, connection points only are necessary, namely for the rows and for the columns, and it is immediately apparent that the number of switches previously required by one detonator switch can, thanks to the invention, be equal to the sum of the rows and columns of the matrix (in the example the number is equal to 10 only). Therefore, the assembly according to the invention has a simpler wiring, consumes less power for its control, is

  less bulky and has increased reliability.

  The saving in hardware (cabling and circuit components) is all the more important as the number of

  cartridges or detonators to ignite is more important.

  For example, if the charger includes 100 cartridges, there must be 101 connections in the prior art, whereas, because of the invention, it is sufficient to have only 20 connection points and 20 switches, that is, to say 10

per line and 10 per column.

  It should also be observed that if the control switches C1 to Cn and Li to Ln are transistors, their control signal must first be brought to the desired level by an amplifier. The drastic reduction in the number of switches required leads to an exactly identical reduction of these amplifiers. In the case of the invention, the integrated circuit necessary for the control therefore has a reduced size and the overall consumption of the

  firing circuit will be significantly lower.

  Another advantage of the circuit according to the invention lies in a better pyrotechnic safety. While in the prior art, the accidental closure, for example by a failure of a single switch can immediately cause the firing of the corresponding cartridge, in the invention requires a failure of two switches at a time to drive an untimely fire. In the same context, an accidental connection to the positive terminal of the power supply

  will not cause accidental firing.

  FIG. 3 represents a variant of the firing circuit according to the invention. This variant is intended to provide redundancy not only to avoid the neutralization of a line or an entire column in the case where, in the configuration of Figure 2, a switch was to be bypassed accidentally, but also to prevent a lack of power supply in case of

  failure of the GC current generator.

  This safety redundancy firing circuit thus comprises two current generators GC1 and GC2 connected in parallel to the positive terminal B1 of the energy source and furthermore connected in parallel to two redundancy switches 1C and 2C. These serve two 1AC and 2AC column feed lines. These lines are respectively connected via column switches 1C1 to 1Cn and 2C1 to 2cn to the columns C1 to Cn of the matrix M which is moreover

  identical to that described with reference to Figure 2.

  Similarly, the other terminal B2 of the power source (the ground) is connected to two redundancy switches 1L and 2L which connect this terminal B2 to two supply lines 1AL and 2AL. These are respectively connected to switches 1L1 to 1L1 and 2L1 to 2Ln also connected to the respective lines 11 to 11 of the matrix M. Therefore, it is understood that, if a short circuit occurs on one of the switches of a group

  switches (for example the group lC1 to lCn which up to

  there was switched on via the switch 1C), we can keep the operation of the firing circuit by opening the switch 1C and closing the redundancy switch 2C which will now involve the column switches 2C1 to 2Cn. The same process can naturally apply to switches

line.

  It should be noted that even in the case of Figure 3, we finally arrive to use a much smaller number of switches than in the previous circuit, especially

  if the matrix has a large number of detonators.

  For technological reasons that do not have to be exposed here, it is easier to make line switches than column switches. FIG. 4 thus shows an advantageous arrangement comprising an extended matrix M1 whose columns C1 to c9 are common to two ammunition or loaders, while the lines 11 to 18 and 19 to 116 are respectively divided into two individualized groups for these munitions. Of course, each intersection of this extended matrix M1, is provided with a detonator Rn and a diode Dn, as

  symbolically indicated in the circle A of FIG.

  In the example of FIG. 4, the number of connection points and switches is even smaller than in the case of FIG. 2. For example, with an extended matrix M 1 such as that of FIG. of 9 + 8 + 8 = 25 if no redundancy is envisaged and of (9 + 1) * 2 + {(8 + 1) * 2} * 2 = 56 with a redundancy of the type of FIG. the

  total number of detonators is 144.

Claims (4)

  1. Firing circuit for ammunition with multiple cartridges, each cartridge being equipped with a detonator (R1 to Rn) which through a switch (C1 to Cn, Li to Ln; lC1 to lCn, 2C1 to 2Cn, lLl to lLn, 2L1 to 2Ln) is selectively connectable to the terminals (B1, B2) of a source of electrical power for firing according to a predetermined firing program, characterized in that said detonators (R1 to Rn) are connected in a matrix (M; M1) having column conductors (C1 to Cn) and line conductors (11 to 11) respectively connected by one of their ends to said terminals (B1). , B2) through said switches (C1 to Cn, L1 to Ln; 1C1 to 1Cn, 2C1 to 2Cn, 11 to 11n, 2L1 to 2Ln) and that at each intersection (IN) of a line conductor ( 11 to 11) and a column conductor (cl to cn), these conductors are interconnected by the series connection of a detonator (R1 to Rn) and a omposant (D1 to Dn) to   unidirectional conduction of the current.   2. Firing circuit according to claim 1, characterized in that said conductive component   unidirectional current is a diode (D1 to Dn).   3. Firing circuit according to any one   Claims 1 and 2, characterized in that said   ends of said line conductors (11 to 11) and said column conductors (cl to cn) are connected to said terminals (B1, B2) of said power source through two groups of switches in parallel (C1 to Cn, L1 to Ln, respectively 1Cl to 1Cn, 2C1 to 2Cn, 1L1 to 1Ln, 2L1 to 2Ln) and redundancy switches (1L, 2L, 1C, 2C) in series allowing selection of one or the other group of switches in case of failure of a switch of a group.   4. Circuit according to any one of claims 1 to 3, characterized in that it serves   several ammunition each associated with a matrix (M, M1) and in that the column conductors (C1 to Cn) of these matrices 5 thus arranged are common.