FR3049056A1 - STARTING DEVICE FOR A PYROTECHNIC LOAD AND AMMUNITION INCORPORATING SUCH STARTING DEVICE - Google Patents

Abstract

The invention relates to a priming device (22) for a pyrotechnic charge (20) disposed in a pot (10) placed in the tube of a munition, which device comprises a pyrotechnic component (24) allowing igniting the pyrotechnic charge (20). This device is characterized in that the pyrotechnic component (24) is a percussion component which is intended to be disposed with its axis (25) perpendicular to that (19) of the pyrotechnic charge (20), a pyrotechnic component which is initiated by a striker (32) integral with a slide (31) which is intended to be held immobile by the tube (2) of the ammunition and which slides, driven by motor means, when the priming device is ejected with the pot (10) out of the ammo. The invention also relates to a munition incorporating at least one pot comprising such a priming device.

Description

The technical field of the invention is that of priming devices and in particular priming devices for a pyrotechnic charge, such as a dispersion charge of a fractionated material (for example masking or decoy) disposed in a pot put up in the tube of a munition.

It is known to provide close defense ammunition armored vehicles which comprise one or more pots of smoke masking compositions or inert which are dispersed out of a tube.

Patent EP0293273 describes such an ammunition which comprises two pots of fuming pyrotechnic composition and a pot of brass powder providing instantaneous infrared masking. A pyrotechnic ejection charge, such as a propellant, causes the ejection of all the pots out of the tube of the ammunition and, at the same time, ensures both the ignition of the fumigene pyrotechnic composition and that of a pyrotechnic delay allowing the ignition of a "rod of dispersion of the brass powder.

The dispersion rod of the brass powder can be initiated by the ejection charge by virtue of the presence of the axial channel passing through the pots of smoke composition.

It is now sought to produce ammunition that may include a stack of several pots of dispersible fractional material. It will thus be possible to combine pots of brass powder with pots of carbon fibers. Brass providing masking in the infrared range and carbon fiber masking in the millimeter range.

Each pot has its pyrotechnic dispersion load rod and it is no longer possible to initiate all these rods from the single ejection charge because there is no axial channel allowing the passage of flame through of the median pot. It is the object of the invention to provide a priming device for igniting a pyrotechnic charge of a pot ejected out of a tube without using the pyrotechnic ejection of the pot. The invention thus makes it possible to initiate the pyrotechnic charges of one or more pots without it being necessary to have an axial channel passing through the different pots. The invention also relates to an ammunition implementing such a device.

Thus, the subject of the invention is a priming device for a pyrotechnic charge, placed in a pot which is intended to be placed in the tube of a munition, a device comprising a pyrotechnic component enabling the ignition of the charge. pyrotechnic and which is intended to be positioned at an end face of the pot, characterized in that the pyrotechnic component is a percussion component which is intended to be disposed with its axis perpendicular to the axis of the load pyrotechnic pyrotechnic component which is initiated by a striker secured to a drawer which is intended to be held immobile by the tube of the ammunition and which slides, driven by motor means, when the priming device is ejected with the pot out of the ammunition tube.

According to a particular embodiment, the motor means may comprise at least one spring interposed between a bearing surface of the device and the drawer.

Advantageously, the priming device may comprise a firing security means comprising a latch solidarizing the drawer and a body of the device, which latch will be erased by the effect of the inertia due to firing.

The lock may comprise a tongue that can be disengaged from a housing of the drawer by the action of an inertial flyweight.

The inertial flyweight may be constituted by a ball. The invention also relates to an ammunition comprising at least one pot disposed in a tube and which can be ejected from this tube by an ejection charge, which container contains a pyrotechnic charge which is initiated by a priming device according to the invention.

The munition according to the invention may comprise at least one pot of a fractionated material disposed in the tube, the fractionated material being dispersible, after ejection of the pot, the pyrotechnic charge initiated by the priming device being a charge allowing the dispersion Fractional material.

The priming device may be attached to the pot at a face of the latter furthest from the ej ection charge.

The munition according to the invention may comprise at least one pot, disposed in the tube, of a fumigene pyrotechnic composition, the pyrotechnic charge initiated by the priming device being an ignition charge of the fumigene pyrotechnic composition. The invention will be better understood on reading the following description of a particular embodiment, description made with reference to the accompanying drawings and in which: - Figure 1 is a schematic longitudinal sectional view of a munition according to an embodiment of the invention; - Figure 2 is a longitudinal sectional view of a pot equipped with a device according to the invention; - Figure 3 is an enlarged view of the priming device according to Figure 2, this view is a longitudinal section taken along the plane whose trace BB is shown in Figure 4; - Figure 4 is a cross sectional view of the device, view taken along the plane whose trace AA is shown in Figure 3.

FIG. 1 shows a munition 1 according to one embodiment of the invention, a ammunition-type ammunition blank that is intended to be placed in a launcher tube that is not shown and that is integral with a fixed platform or a vehicle (such a launcher tube is for example described in patent FR2765869).

This ammunition 1 comprises a tube 2 at the rear part -which is a base 3, screwed on it, and which carries a radial lug 4 for fixing the ammunition by a bayonet mounting on a launcher not shown. The base 3 carries an axial contact 5 electrically isolated from the base by an insulating cylinder 6. The base 3 contains a pyrotechnic ejection charge 7 (a propellant powder for example) and an igniter 8 which is electrically connected, partly on the contact 5 and on the other hand with the metal body of the base 3. The tube 2 encloses a piston 9 which separates the pyrotechnic ejection charge from several active jars: a first jar containing a masking material fractionated and dispersible; a second pot 11 also containing a fractional and dispersible masking material; a pot 12, the closest to the piston 9, enclosing a fumigene pyrotechnic composition 13.

This fumigant composition 13 is initiated by an annular ignition tablet 14 which is placed between two blocks of the fumigant composition 13. The ignition tablet 14 is itself initiated by the gases of the pyrotechnic ejection charge 7 which makes it reach through a hole 15 through the piston 9.

The smoke composition 13 and the ignition tablet 14 comprise an axial channel 16 which facilitates the ignition of the composition 13 over its entire height. The flame resulting from the pyrotechnic ejection charge 7 also makes it possible to initiate an ignition component (not shown) which is integral with the second pot 11 which encloses a fractionated material, for example a brass powder allowing instant infrared masking, material associated with an explosive rod allowing its dispersion (not shown).

Such an architecture associating a pot of fuming pyrotechnic composition and a pot of brass powder-dispersible is described by patent EP0293273 to which reference may be made for more details.

The first pot 10 comprises a case 18 which contains a stack of slabs 17 of conductive fibers having a masking efficiency in the millimeter range (frequency 35 to 94 GHz).

The slabs 17 (here six slabs) are formed of carbon fibers or aluminized glass fibers. All the fibers are arranged parallel to each other and parallel to the axis 19 of the ammunition 1 and the pot 10.

Each slab 17 thus has for thickness the length of the fibers, ie 3mm to 6mm. A method for producing such patties is described in patent FR2797044.

As can be seen in FIG. 1, some slabs 17 are solid and other slabs 17 have an axial hole which allows the installation of a pyrotechnic dispersion charge 20 which is housed in a cane 21. therefore does not extend over the entire length of the case 18.

A priming device 22 is attached to the first pot 10.

This device 22 is not detailed in this figure 1 but it will be more visible in the other figures.

A stopper 23 finally closes the tube 2 of the ammunition. This plug 23 is connected to the tube 2 by at least one shearable pin (not shown).

Thus, when the ejection charge 7 is ignited by the igniter 8, the pressure of the gases will push the piston 9 which will push the stack of the pots 10, 11 and 12 which will cause the shearing of the pin fixing the cap 23 and the ejection of the three pots out of the tube 2.

At the same time, the ejection gases will initiate the ignition tablet 14 which will ignite the fumigated pyrotechnic composition 13 of the pot 12. The ejection gases coming from the ejection charge 7 follow the axial channel 16 and will also light up. the explosive composition associated with the second pot 11 (and which is also associated with a delay as described in patent EP0293273).

On the other hand, the ejection gases can not ignite the pyrotechnic dispersion charge 20 which is housed in the rod 21.

It is indeed not possible to provide a flame channel through the second pot 11.

According to the invention, the pyrotechnic dispersion charge 20 is thus initiated by the priming device 22 which is positioned at an end face 10a of the first pot 10.

Referring to FIG. 2 which shows the first pot 10 (without the fiber pancakes 17), it can be seen that the priming device 22 comprises a pyrotechnic ignition component 24. This component is a percussion component which is arranged with its axis 25 perpendicular to the axis 19 of the pyrotechic dispersion charge 20 disposed in the rod 21.

As seen more particularly in Figures 3 and 4, the priming device 22 comprises a body 26 formed of two parts 26a and 26b. These two parts are connected to each other by an axial screw 27 which cooperates with a tapping of a head 28 of the rod 21.

The ignition component 24 is pinched between the two parts 26a and 26b of the body 26 which delimit a radial bore 29 which can receive the component 24.

The two parts 26a and 26b also delimit a housing 30 inside which can slide a slide 31 which extends transversely over the entire diameter of the device 22.

As can be seen more particularly in FIG. 4, the housing 30 is delimited by two parallel flat surfaces 30a and 30b which are symmetrical with respect to the diametrical plane BB of the device 22 which passes through the axis 25 of the pyrotechnic component 24.

The drawer 31 carries a striker 32 which is crimped in a housing 33.

As seen in Figure 4, the device 22 comprises two compression springs 34 which are each disposed between a bearing surface 35, carried by the body 26 of the device, and the drawer 31. In the safety position shown in FIG. 4, the springs 34 are compressed and they radially push the slide 31 in the direction indicated by the arrow Z.

The drawer 31 is held stationary in this safety position by the tube 2 of the ammunition which has been partially shown in FIGS. 3 and 4.

As seen in FIGS. 3 and 4, the axial screw 27 comprises a housing which encloses a pyrotechnic charge 41 which combines a layer of a relay composition which makes it possible to ignite the pyrotechnic dispersion charge 20 and a layer of light. a pyrotechnic delay composition for delaying the initiation of the dispersion charge by a few tenths of seconds after ejection of the first pot 10 out of the tube 2.

The pyrotechnic charge 41 is initiated radially at its rear end by the component 24. To enable this initiation, the screw 27 comprises four radial bores of which at least one, marked 42 in the figures, is opposite the component 24.

The priming device 22 also comprises a firing safety means which comprises a lock 36 for securing the drawer 31 and the body 26 of the device.

The lock 36 is constituted by a sheet metal tongue having two wings 36a and 36b. A first wing 36a is housed in a slot in the upper part 26a of the body 26.

A second wing 36b is housed in a slot 37 carried by an edge 38 of the drawer 31 (Figure 3). A metal ball 39 is disposed between the tongue 36 and the body 26. A clearance 40 is disposed between the tongue 36 and the lower portion 26b of the body 26. The ball 39 constitutes an inertial flyweight. During the ejection of the pot 10 out of the tube 2, the shooting inertia causes the ball 39 towards the clearance 40. The ball then causes the deformation of the tongue 36 and the extraction of the second wing 36b out of the slot 37 of the drawer 31.

The latch formed by the tongue 36 is thus erased by the effect of the inertia due to the shot.

The drawer 31 is held by the wall of the tube 2. When the first pot 10 is ejected from the tube 2, as soon as the device 22 is no longer facing the tube 2, the drawer 31 is no longer held in position. safety position and slides, driven by the motor means formed by the springs 34.

The striker 32 then initiates the pyrotechnic component 24 which initiates the charge 41 which will ensure the initiation of the dispersion charge 20.

It can be seen that, with the invention, the initiation of a pyrotechnic charge for dispersing a pot can be easily ensured without it being necessary to drive towards this charge a portion of the gases of the pyrotechnic ejection charge 7 , through an axial chimney. The invention thus greatly simplifies the design of the ammunition masking or decoy. Indeed, each dispersion pot can thus carry its own priming device whose initiation will simply be provided by the ejection of the pot out of the tube of the ammunition.

It would thus be possible to provide a device according to the invention for initiating the pyrotechnic charge for dispersing the second pot 11.

As can be seen in FIGS. 3 and 4, the drawer 31 has a hole 43 which is coaxial with holes 44a and 44b "carried by the parts 26a and 26b of the body 26. These holes can receive a locking rod (not shown ) which will maintain the drawer 31 in the safety position during the assembly phase (or disassembly) of the device.

The securing means of the device 22 and the pot 10 have not been described. This fastening can be achieved by screwing the body 26 on the case 18 or by gluing or by clipping, for example by providing lights on the body 26 receiving tabs of the case 18.

Various variants are possible without departing from the scope of the invention.

It is thus possible to fix the device 22 at the other side of the first pot 10, that is to say between the first pot 10 and the second pot 11. Of course, the dispersion rod 21 will still be attached to the device 22. However, it will be necessary to mount the device relative to the rod 21 in a symmetrical manner with respect to the plane AA with respect to the configuration shown in FIG. 3. This is so that the ball 39 plays. still its role of inertial flyweight to release the lock 36 during the ejection of the pot.

It is possible to define a munition comprising any number of pots filled with a fractionated material to be dispersed, each pot being equipped with a priming device according to the invention. A munition could thus comprise only one dispersion pot equipped with the device according to the invention.

Fractional material is not the subject of the present invention. This material may be formed by millimetric masking fibers, an infrared masking powder, decoy flakes ... The invention has been described in an ammunition application comprising at least one pot of a dispersible fractionated material. It is also possible to use the ignition device according to the invention to ensure the ignition of a pyrotechnic charge which is not a dispersion charge of a dispersible material but a pyrotechnic charge ensuring ignition of a fumigene pyrotechnic composition or the initiation of an explosive charge.

In particular it is possible, on the ammunition shown in Figure 1, to ensure the initiation of the smoke composition of the pot back 12 with the aid of a priming device according to the invention. In this case, an appropriate ignition load will be provided which will be housed in a rod positioned in a portion of the axial channel 16. This ignition charge will be initiated by a percussion component 24 of an ignition device according to the invention. .

Such an embodiment avoids using a borrowing of propellant gases to ensure the ignition of the smoke pot 12.

It is also possible to associate the priming device according to the invention with a pot of a smoke composition in which the ignition composition is disposed on a flat end surface of the smoke composition. Such a pot is known, for example patents US5522320 and GB2382640, and it may not include a central channel. The loading density in smoke composition can then be optimized.

Claims (9)

A priming device (22) for a pyrotechnic charge (20) arranged in a pot (10) which is intended to be placed in the tube (2) of a munition (1), a device comprising a component pyrotechnic device (24) for igniting the pyrotechnic charge (20) and which is intended to be positioned at an end face (10a) of the pot (10), characterized in that the pyrotechnic component (24) ) is a percussion component which is intended to be disposed with its axis (25) perpendicular to the axis (19) of the pyrotechnic charge (20), pyrotechnic component (24) which is initiated by a striker (32) integral with a drawer (31) which is intended to be held immobile by the tube (2) of the ammunition and which slides, driven by motor means (34), when the priming device (22) is ejected with the pot (10) out of the tube (2) of the ammunition. 2- priming device according to claim 1, characterized in that the motor means (34) comprise at least one spring interposed between a bearing surface (35) of the device and the drawer (31). 3- priming device according to one of claims 1 or 2, characterized in that it comprises a firing safety means comprising a latch (36) solidarisant the drawer (31) and a body (26) of the device (22). , which is erased by the effect of the inertia due to the shot. 4- Priming device according to claim 3, characterized in that the latch (36) comprises a tongue (36b) which can be disengaged from a housing (37) of the drawer (31) by the action of a feeder inertial (39). 5. Priming device according to claim 4, characterized in that the inertial flyweight (39) is constituted by a ball. Ammunition (1) comprising at least one pot (10) arranged in a tube (2) and which can be ejected from this tube by an ejection charge (7), pot (10) which contains a pyrotechnic charge ( 20) which is initiated by a priming device (22) according to one of the preceding claims. 7- A munition according to claim 6, comprising at least one pot (10) of a fractionated material disposed in the tube (2), the fractionated material being dispersible, after ejection of the pot (10), the pyrotechnic charge (20) initiated by the priming device (22) being a filler allowing the dispersion of the fractionated material. 8- A munition according to claim 7, characterized in that the priming device (22) is fixed to the pot (10) at a face (10a) of the latter furthest from the ejection charge (7). ). 9- Ammunition according to claim 6, comprising at least one pot, disposed in the tube, a pyrotechnic fumigant composition, the pyrotechnic charge initiated by the priming device being an ignition charge of the fumigene pyrotechnic composition.