FR3075946A1 - DEVICE FOR GENERATING FLANKS - Google Patents

Abstract

The invention relates to a chip generating device (1) comprising a housing in which an explosive charge (3) is located, the housing comprising a first end to which is located an initiator (4) of the explosive charge (3). and a second end opposite the first end, a projectile (5) being located in the housing between the explosive charge (3) and the second end, characterized in that the projectile (5) comprises a plurality of elementary projectiles (51) interconnected by connection elements (52) which each define a zone of reduced thickness of the projectile (5), the whole projectile (5) being monolithic.

Description

Invention background

The present invention relates to the general field of burst generators for tests on burst projection mapping systems for ammunition tests.

In order to test a munition, and in particular to determine the spatial distribution, the mass, the speed and the shape of the fragments of the ammunition when said ammunition is used, said ammunition is fired in a system of mapping of projections of fragments ammunition.

However, tests must be carried out on such a mapping system, in particular for the development and design of said mapping system, in order to control said mapping system. Such tests are carried out with a test ammunition, also called a chip generation device, which offers the advantage of being less expensive and more easily handled than a real ammunition.

One problem with current chip generation devices is that they are relatively expensive to use. Indeed, the known chip generation devices generate many chips with a large spatial dispersion, thus making it particularly necessary to use many targets to perform the test.

Subject and summary of the invention

The main object of the present invention therefore is to overcome such drawbacks by proposing a device for generating splinters having a reduced cost of use.

Thus, the invention provides a device for generating splinters comprising a housing in which an explosive charge is located, the housing comprising a first end at which is located an initiator of the explosive charge and a second end opposite the first end, a projectile being located in the housing between the explosive charge and the second end, characterized in that the projectile comprises a plurality of elementary projectiles connected together by connection elements which each define an area of reduced thickness of the projectile, the whole projectile being monolithic.

Such a chip generation device makes it possible to limit the spatial dispersion of the chips. Indeed, the fact that the projectile comprises elementary projectiles linked together by connection elements, and that said projectile is monolithic makes it possible to delay the moment when the elementary projectiles will disperse, thus reducing the spatial dispersion of the elementary projectiles, and so shards.

The splinter generation device can also include the following characteristics, taken alone or in combination depending on the technical possibilities: - the projectile is made of a first material having a first density, and in which a layer of a second material is located between the projectile and the second end of the housing, the second material having a second density less than the first density; - the second material consists of an organic material; - The second material is polymeric, for example silicone, or a grease, for example paraffin; - the connection elements are rods; - The housing is a cylinder having a main axis of elongation, and in which the elementary projectiles are all located in the same plane which is transverse, for example perpendicular, to the main axis of elongation of said housing; - The housing is formed by a body, an explosive support being located inside the housing, the explosive charge being located inside said explosive support; - the body is polymeric; - the body is metallic; - The body protrudes from the explosive support at the second end of the housing, so as to form a cavity in which the projectile is located.

BRIEF DESCRIPTION OF THE DRAWINGS Other characteristics and advantages of the present invention will emerge from the description given below, with reference to the accompanying drawings which illustrate examples of embodiment which are devoid of any limiting character. In the figures: - Figure la illustrates a sectional view of a device for generating splinters according to an embodiment of the invention, in which the layer of the second material is not shown; - Figure lb illustrates the sectional view of Figure 1, on which the layer of the second material is shown; - Figure 2 shows a front view of the chip generating device of Figure 1, in which the layer of the second material is not shown; - Figure 3 shows a sectional view of a chip generation device according to another embodiment of the invention.

Detailed description of the invention

As illustrated in FIGS. 1a, 1b and 2, a device for generating splinters 1 comprises a housing 2 defined by a body 21 inside which an explosive charge 3 is disposed. The body 21 can be one of cylindrical shape according to a main axis of elongation Θ, the housing 2 also forming a cylinder of axis Θ, typically a cylinder of revolution or a parallelepiped.

The chip generation device 1 comprises an initiator 4 of the explosive charge 3 at a first end 2a of the housing 2 in order to ignite said explosive charge 3 and thus use the chip generation device 1. As illustrated in the Figure 1, the initiator 4 of the explosive charge 3 passes through a wall obstructing the first end 2a of the housing 2 so that the initiator 4 is connected on the one hand to the explosive charge 3 and on the other hand to a control system the ignition of the chip generation device 1.

The splinter generation device 1 also comprises a projectile 5 which is made of a first material, for example metallic, and which is intended to be propelled by the explosion of the explosive charge 3. This propulsion of the projectile 5 by explosion of the explosive charge 3 makes it possible to generate fragments, from said projectile 5, in order to test a system of mapping of projection of fragments. To do this, the projectile 5 is located in the housing 2, between the explosive charge 3 and a second end 2b of said housing 2 which is open towards the outside, so that said projectile 5 can be expelled towards the outside of said device. 1).

In order to reduce the spatial dispersion of the fragments and concentrate said dispersion of the fragments around the axis Θ, the projectile 5 comprises a plurality of elementary projectiles 51 connected together by connection elements 52, the whole of the projectile 5 being monolithic. The connection elements 52 each define an area of reduced thickness of the projectile 5. Thus, as illustrated in FIG. La, the elementary projectiles 51 have a first thickness el, preferably the same thickness for all the elementary projectiles 51, and the connection elements 52 have a second thickness e2 which is less than the first thickness el. The second thickness e2 is for example less than or equal to half of the first thickness el (e2 <0.5 x el), for example less than or equal to a quarter of the first thickness el (e2 <0.25 x el).

The plurality of elementary projectiles 51 makes it possible to generate a plurality of fragments of sufficient size similar to those generated by the body of an ammunition. An elementary projectile 51 can form a single or a plurality of fragments depending on whether said elementary projectile 51 remains whole or else said elementary projectile 51 is fragmented following the explosion of the explosive charge 3, in particular because of the flaking caused by the crossing between the trigger waves following the initial shock and the trigger waves of the first reflection of the initial shock on the rear face of the elementary projectile 51.

Such a projectile 5 makes it possible to reduce the dispersion of the splinters because the connection elements 52 which connect the elementary projectiles 51 make it possible to delay the dispersion of said elementary projections 51. Indeed, the connection elements 52 hold together all the elementary projectiles 51 around the axis Θ at the start of the projection of the projectile 5 out of the splinter generation device 1. The connection elements 52 will then break, and cause the dispersion of the elementary projectiles 51. The rupture of the connection elements 52 is caused by the fact that said connection elements 52 are zones of weakness of the projectile 5 with their smallest thickness. The fact that the entire projectile 5 is monolithic, that is to say that the elementary projectiles 51 and the connection elements 52 are in one and the same piece, makes it possible to reduce the dispersion of the elementary projectiles 51, and therefore to limit the dispersion of the fragments. Indeed, the fact that the projectile 5 is monolithic makes it possible to delay the rupture of the connection elements 52, in particular with respect to a solution where the connection elements 52 are rods attached to the elementary projectiles 51, as referred to or glued to said said elementary projectiles 51.

In order to monolithically manufacture the elementary projectiles 51 and the connection elements 52, the projectile 5 can be manufactured by machining, the connection elements 52 then being formed by shrinking material, or by three-dimensional printing.

In the example illustrated in the figures, the elementary projectiles 51 are cubes and the connection elements 52 are rods which connect said cubes. However, other forms may be possible. For example, the elementary projectiles 51 can be spheres.

Furthermore, as visible in FIGS. 1a and 2, the projectile 5 comprises five elementary projectiles 51, but other numbers of elementary projectiles 51 are possible. The elementary projectiles 51 are advantageously all arranged in the same plane which is transverse, for example perpendicular, to the axis Θ, so as to further limit the spatial dispersion of the fragments and to focus it more on the axis Θ. Preferably, the elementary projectiles 51 are all identical, and / or the connection elements 52 are all identical. However, according to other possible variants, the elementary projectiles 51 may be identical and the connection elements 52 are different, for example the connection elements 52 have different lengths, or else the connection elements 52 are all identical and the projectiles elementary 51 are different.

The projectile 5 preferably has a symmetrical shape with respect to a center of symmetry, in order to limit the spatial dispersion of the fragments. However, the projectile 5 can have an asymmetrical shape.

In addition, according to an example of possible arrangement, an elementary projectile 51 is located on the axis Θ, and the other four elementary projectiles 51 are arranged symmetrically around the axis θ. It is advantageous that the projectile 5 is centered on the axis θ of the splinter generation device 1, and that said projectile 5 has a shape having central symmetry with a center of symmetry located on the axis Θ, in order to limit more the spatial dispersion of the fragments and to focus it more around the axis l'axe. According to a possible variant, the projectile 5 can have a symmetrical shape with respect to a point located on the axis θ without an elementary projectile 51 being located on said axis Θ.

Advantageously, as illustrated in FIG. 1b, a layer 6 of a second material is located between the projectile 5 and the second end of the housing 2, so that said projectile 5 is covered by said layer 6 of the second material, the second material being in contact with the projectile 5. The layer 6 of second material is in contact with the explosive charge 3 on zones situated between the elementary projectiles 51. The second material has a second density which is lower than the first density of the first material constituting the projectile 5. The second material is preferably made of an organic material, such as for example a polymeric material or a grease. The polymeric material may for example be silicone, and the grease may for example be paraffin. This has the advantage of being a simple solution to implement, and inexpensive. Such a layer 6 makes it possible to reduce the flaking that elementary projectiles can undergo 51, which reduces the number of fragments and the spatial dispersion of said fragments. Indeed, during a test, fragments are generated by a fragmentation of the elementary projectiles 51 caused by the flaking of said elementary projectiles, the generation of such flaking fragments increasing the spatial dispersion of the fragments of the projectile 5.

In the embodiment illustrated in the figures, an explosive support 22 is located inside the housing 2, the explosive charge 3 being located inside said explosive support 22. The explosive support 22 is located between the body 21 and the explosive charge 3, and is in contact with said body 21 on its outer contour, and is in contact with said explosive charge 3 on its internal contour. The explosive support 22 comprises a first end closed by a bottom through which the initiator 4 passes, and a second end opposite to said first end and which is situated on the side of the second end 2a of the housing 2. In the example illustrated in the figures, the first end of the body 21 is located between the first and the second end of the explosive support 22, and the second end of said body 21 projects beyond the second end of said explosive support 22, so as to form a cavity 7 in which the projectile 5 is located. The layer 6 of the second material 6 is also located in the cavity 7 defined by the body 21.

The body 21 can be made of metal or of polymer material. The metal offers the advantage of better resistance, and the polymer material offers the advantage of being lighter and less expensive. The material of the body 21 also makes it possible to influence the speed of projection of the elementary projectiles 51.

Furthermore, as illustrated in FIG. 3, several forms are possible for the explosive support 22. Thus, the explosive support 22 can comprise a fixing flange 22a at its first end.

Claims (10)

1. Device for generating splinters (1) comprising a housing (2) in which an explosive charge (3) is located, the housing (2) comprising a first end (2a) at which is located an initiator (4) of the explosive charge (3) and a second end (2b) opposite the first end, a projectile (5) being located in the housing between the explosive charge (3) and the second end (2b), characterized in that the projectile (5) comprises a plurality of elementary projectiles (51) connected together by connection elements (52) which each define an area of reduced thickness of the projectile (5), the whole of the projectile (5) being monolithic. 2. Device for generating splinters (1) according to claim 1, in which the projectile (5) is in a first material having a first density, and in which a layer (6) of a second material is located between the projectile (5) and the second end of the housing, the second material having a second density less than the first density. 3. Device for generating splinters (1) according to claim 2, in which the second material consists of an organic material. 4. Device for generating splinters (1) according to claim 3, wherein the second material is silicone or paraffin. 5. Device for generating splinters (1) according to any one of claims 1 to 4, in which the connection elements (52) are rods. 6. Device for generating splinters (1) according to any one of claims 1 to 5, in which the housing is a cylinder having a main axis of elongation (Θ), and in which the elementary projectiles (51) are all located in the same plane which is transverse to the main axis of elongation (Θ). 7. Device for generating splinters (1) according to any one of claims 1 to 6, in which the housing (2) is formed by a body (21), an explosive support (22) being located at the inside the housing (2), the explosive charge (3) being located inside said explosive support (22). 8. Device for generating splinters (1) according to claim 7, in which the body (21) is made of polymeric material. 9. A splinter generation device (1) according to claim 7, in which the body (21) is made of metal. 10. Device for generating fragments (1) according to any one of claims 7 to 9, in which the body (21) protrudes from the explosive support (22) at the second end of the housing (2), so as to form a cavity (7) in which the projectile (5) is located.