WO2020007585A1

WO2020007585A1 - Projectile hull and production method

Info

Publication number: WO2020007585A1
Application number: PCT/EP2019/065480
Authority: WO
Inventors: Markus Bähr; Felicitas MARX; Michael Biedermann
Original assignee: Diehl Defence Gmbh & Co. Kg
Priority date: 2018-07-06
Filing date: 2019-06-13
Publication date: 2020-01-09
Also published as: DE102018005371B4; DE102018005371A1; EP3818325A1

Abstract

The invention relates to a projectile hull (2) comprising a hull body (4) enclosing an inner space (6), with at least one predetermined breaking point (10) for weakening and breakdown into fragments (12), said projectile hull being produced by 3D printing and the predetermined breaking point (10) being formed such that the reactant (16) is not compacted or is only slightly compacted, and/or only a little or no reactant (16) is provided, wherein the hull body (4) has a continuous inner wall (20) and/or outer wall (22) on the predetermined breaking point (10). According to a method for producing the projectile hull (2), the reactant (16) is provided and the hull body (4) is produced by means of 3D printing, wherein the predetermined breaking point (10) is formed as described, and a continuous inner wall (20) and/or outer wall (22) is produced on the predetermined breaking point (10).

Description

Bullet casing and manufacturing process

The invention relates to a projectile shell with an enveloping body surrounding an interior, which has at least one predetermined breaking point for mechanical weakening and targeted disassembly of the enveloping body into at least two fragments. For example, a warhead shell is known from DE 195 24 726 B4, which is in the range of

Cutting charges has predetermined breaking points, which are introduced in the form of depressions in the outer wall.

The object of the present invention is to propose a projectile shell which is improved in relation to predetermined breaking points.

The object is achieved by a projectile casing according to patent claim 1.

Preferred or advantageous embodiments of the invention and others

Invention categories result from the further claims, the following description and the attached figures.

The projectile envelope contains an envelope body which delimits an interior space. The interior is used to hold other structural elements of a projectile (explosives, active elements, detonators, etc.). The enveloping body forms in particular the casing, wall, support structure of the projectile or at least part of it. The enveloping body has at least one predetermined breaking point. The predetermined breaking point serves to mechanically weaken the enveloping body. At a later detonation The shell of the projectile breaks at the predetermined breaking point (s) and is deliberately broken down into at least two or a plurality of fragments.

The projectile casing can have further additional elements, for example a cover and an end piece.

The envelope body, in particular the entire projectile envelope, is produced by means of a 3D printing process. The enveloping body is in particular in one piece. In this process, the envelope is made from a raw material. The raw material is solidified into the actual envelope. "Solidification" is to be understood in particular to mean any form of sintering, hardening, melting, gluing, etc., the processes being able to take place physically and / or chemically, etc. The 3D printing process creates a material of a certain hardness or

Strength or stability. As materials here in particular metals, but also ceramics come into question, specifically e.g. B. steel, aluminum or nickel.

The predetermined breaking point is formed by the fact that at the location of the predetermined breaking point

Starting material is not solidified into a solid, solid part of the enveloping body or the correspondingly created part of the enveloping body is mechanically less firm than the remaining part (not formed by the predetermined breaking points) of the enveloping body.

Alternatively or additionally, less or none at the predetermined breaking point

Starting material can be used as in the solid, solid parts of the envelope. This results in either an empty space on or in the envelope or also a structurally weaker section.

In other words, the envelope body itself is uniformly produced with the 3D printing process with the corresponding same material properties (strength, hardness, resilience, ...) that usually result from the given 3D printing process. At the predetermined breaking points, however, either no material is deliberately built up in or on the enveloping body or the material of the enveloping body is there compared to that by the 3D printing process

Usually achievable strength, quality, resilience, etc. in the other parts of the envelope deliberately weakened. This is particularly due to the

Contribution of little or no (or at least partial removal von) Starting material as usual or achieved by a reduced or not carried out solidification of the starting material.

The enveloping body has a continuous inner wall and / or outer wall, in particular inner wall and outer wall, at the predetermined breaking point. "Wall" is to be understood here in terms of a surface. In particular, the predetermined breaking point is therefore not an opening in the enveloping body between its inner wall and outer wall. "At the predetermined breaking point" means: in its immediate vicinity, in particular in the area of the radial projection space of the predetermined breaking point. The radial direction is related to a central longitudinal axis of the projectile shell, which corresponds in particular to the central longitudinal axis or the flight or firing direction of the projectile in the later mounted state of the projectile. In other words, the outer wall and / or inner wall at the predetermined breaking point are formed in the usual way by the starting material solidified to form the enveloping body.

The invention is based on the knowledge that competing design criteria "high active mass vs. low total mass vs. high proportion of energy

Material "for bullet casings.

The invention is based on the consideration that, in order to absorb the launch loads, supporting structures made of solid steel or copper for the

Bullet casing could be used. These could then be used either for detonation-guiding inserts or with mechanically inserted notches for targeted disassembly. Another solution would be to insert structural fragments into the supporting structure. However, for all of these solutions it is necessary to accept performance-reducing influences.

The invention is based on the idea of introducing predetermined breaking points in the wall (envelope body) of the warhead shell (projectile shell) by means of 3D printing, in particular metal printing.

According to the invention, the entire warhead mass (at least the mass of the enveloping body) can be deliberately disassembled and used as acting fragments. A more targeted effect reduces the risk of collateral damage and the overall use a higher active power. This results in a functionalization of the load-bearing shell (envelope body) for targeted disassembly through the use of 3D printing. The entire mass of the projectile casing (at least of the casing body) can serve as fragments, because the shot load by the

pre-fragmented shell is included. Furthermore, the size of the fragments can be adjusted in the direction of disassembly and shape. In particular, a splinter warhead can be realized according to the invention.

According to the invention, there is no longer any need for performance-reducing functions or components in order to disassemble the projectile casing (casing body) in fragments.

According to the invention, all parts of the projectile casing (casing body) can be used as the active mass.

In a preferred embodiment of the invention, therefore, at least one of the fragments is an active element of the projectile. The envelope thus fulfills one

Double function as a load-bearing element of the projectile and active element. The

Active elements are, in particular, construction fragments.

In a preferred variant of this embodiment, the entire envelope can be broken down into fragments and all fragments are respective active elements of the

Projectile shell or the projectile. This creates a particularly effective floor, as has already been explained above.

In a preferred embodiment, the predetermined breaking point is located as an inclusion between the inner wall and the outer wall of the enveloping body. The predetermined breaking point is thus completely inside or the volume of the enveloping body or the wall of the projectile envelope formed by the enveloping body. In other words, there is between the inclusion and the inner wall on the one hand and between the inclusion and the outer wall on the other hand in each case in the usual way completely solidified starting material in the form of the enveloping body. The inclusion is therefore bounded radially inwards and outwards by a casing section or wall section of the casing body. In other words, the envelope body continues in one piece as a respective envelope section both radially inward and radially outward past the inclusion. Such an inclusion is in particular from the outside (i.e. from the inner wall or the outer wall) not recognizable. The predetermined breaking point is thus a (with

Starting material filled or partially filled or empty) cavity inside or as part of the envelope. If starting material is present in the cavity, it is less or not solidified there to form the actually mechanically stable envelope.

In particular, a particularly stable, continuous outer wall and inner wall can be realized next to the cavity (seen in the radial direction).

In particular, the inner wall and / or outer wall can be in the area of the

Predetermined breaking point straight, smooth, flat, etc. can be realized.

The fact that the outer wall and the inner wall are continued in one piece and without interruption in the area of the predetermined breaking point also results in particularly good mechanical stability in the longitudinal direction of the projectile. So this can also withstand the acceleration of the launch particularly well. The envelope body can thus be made with less material and thus more easily than at a predetermined breaking point due to external notches etc. Overall, the envelope sections result in a type of bilateral support or bridge structure that surrounds the predetermined breaking point.

In a preferred embodiment of the invention, the starting material is a loose starting material, in particular a powder. Thus, even if the predetermined breaking point is completely filled with unconsolidated starting material, the starting material has no mechanical stability, or the mechanical stability is comparatively low, so that the enveloping body is weakened particularly effectively there. Nevertheless, the production is simplified since the raw material does not have to be removed at the predetermined breaking point during the 3D printing of the projectile shell. This is particularly advantageous in connection with the above-mentioned inclusion or cavity.

In a preferred embodiment, at the predetermined breaking point, at least in the longitudinal direction of the enveloping body (for example in or against the firing direction), its wall thickness has a non-decreasing or non-increasing course between the solidified edges surrounding the predetermined breaking point. In other words, the inner and / or outer wall runs in the longitudinal direction at the predetermined breaking point without dents, notches, indentations, grooves, grooves. This affects at least the immediate one

Environment of the predetermined breaking point, namely its edges. In particular, they are corresponding properties in other directions, in particular

Circumferential direction / transverse direction, in particular in all directions, d. H. given the predetermined breaking point all around. This leads to a geometrically simple, in particular smooth, shell case.

In a preferred variant of this embodiment, the wall thickness has a constant course between the solidified edges in the longitudinal direction, in particular the other directions mentioned. The inner / outer wall at the predetermined breaking point thus runs in particular smooth, in particular even, cylindrical, conical, spherical, etc. The advantages mentioned above apply accordingly.

In a preferred variant of this embodiment, the wall thickness has a non-decreasing or non-increasing or constant profile in the longitudinal direction of the entire envelope body. The properties described above - in particular of the inner and outer walls - then extend over the entire length of the projectile casing or the casing body. The above advantages apply accordingly.

In a preferred embodiment, the wall thickness in the circumferential direction of the enveloping body is constant at at least one longitudinal position of the enveloping body. This leads accordingly to the advantages mentioned above, but in relation to the

Circumferential direction of the shell.

In a preferred variant of this embodiment, the wall thickness is constant at all longitudinal positions of the enveloping body. The advantages mentioned above therefore apply to the entire length of the envelope.

The object of the invention is also achieved by a method according to

Claim 1 1 for the production of the invention. In the process, the starting material is provided. The envelope is produced by means of a 3D printing process by solidifying the starting material to form the envelope. In this case, the at least one predetermined breaking point is formed in the enveloping body in that the starting material is not solidified there or less or less or no there

Starting material is introduced into the enveloping body as in solidified areas. The Envelope is made at the predetermined breaking point with a continuous inner wall and / or outer wall.

The method and at least some of its embodiments and the respective advantages have already been explained in connection with the projectile casing according to the invention.

Further features, effects and advantages of the invention result from the following description of a preferred exemplary embodiment of the invention and the attached figures. Show, each in a schematic

Schematic diagram:

1 shows a projectile casing according to the invention in longitudinal section,

Figure 2 shows the shell of Fig. 1 in cross section.

Figures 1 and 2 show a projectile shell 2 with an envelope body 4, which an interior 6 of a to be created, not shown and explained

Floor bounded. The cutting lines are drawn in the figures by the lines I-1 for Fig. 1 and II-II for Fig. 2. The interior 6 is also delimited by a cover 5 molded onto the envelope body 4. Envelope body 4 and cover 5 are made in one piece, the boundary between the two is only symbolically indicated by dashed lines. Compared to the cover 5, the projectile casing 2 also has an end piece 7, which is also made in one piece with the casing body 4. Here, too, the border is indicated by dashed lines. The shell 2 has one

Central longitudinal axis 8 and is constructed rotationally symmetrical with respect to its basic shape or external shape.

The enveloping body 4 has a number of predetermined breaking points 10. The enveloping body is mechanically weakened at each predetermined breaking point 10. In the event of a later detonation of the projectile in the event of use, the projectile shell 2 or the shell body 4 breaks at the predetermined breaking points 10. This creates isolated fragments 12 of the shell body as active elements 14, here construction splinters, which are thereby released individually. The fragments are indicated by dashed lines. The enveloping body 4 and here the entire projectile envelope 2 is or is produced in one piece by means of a 3D printing method which is not explained in more detail. Here, a starting material 16, in the example a powder, here steel, becomes a massive,

solidified material of the enveloping body 4 solidified. This is only indicated symbolically in the figure.

The predetermined breaking points 10 are formed in that the starting material 16 is not solidified there. The predetermined breaking points 10 are inclusions 18 or cavities that do not form the rest of the material of the enveloping body 4, i. H. correspond to the solidified starting material 16. Rather, the starting material 16 is still contained in the inclusions 18 as an unconsolidated powder. Alternatively, the starting material 16 is less solidified in the inclusion 18 than in the other enveloping body 4

Predetermined breaking points 10 of the enveloping body 4 are mechanically weakened compared to areas without predetermined breaking points 10. The cavities lie completely in the interior of the enveloping body 4 and are therefore surrounded on all sides by solidified material of the enveloping body 4. The inclusions 18 are thus located completely between an inner wall 20 and an outer wall 22 of the enveloping body. Thus, between the inner wall 20 and the outer wall 22 and the inclusion 18 there is in each case a shell section 24 made of fully solidified starting material 16, which continues the remaining shell body 4 in one piece.

Alternatively, the predetermined breaking points 10 are created in that the starting material 16 is partially or completely removed at their location and the enveloping body 4 is otherwise constructed around the predetermined breaking point 10 or the inclusion 18. The

Enclosure 18 is then an actual cavity that has little or no

Contains starting material 16 as the remaining enveloping body 4 and additionally or exclusively for example air.

The wall thickness d has a constant course both between the respective solidified edges 26 of the predetermined breaking points 10 in the longitudinal direction 30 of the entire enveloping body 4 (along the central longitudinal axis 8, indicated by a double arrow) and in the circumferential direction 28 (indicated by a double arrow). Bezuaszeichenliste

projectile casing

enveloping body

5 lids

6 interior

7 end piece

8 central longitudinal axis

10 predetermined breaking point

12 fragment

14 active element

16 starting material

18 inclusion

20 inner wall

22 outer wall

24 casing section

26 edge

28 circumferential direction

30 longitudinal direction d wall thickness

Claims

claims

1. bullet casing (2) with a casing body (4) which delimits an interior space (6) and which has at least one predetermined breaking point (10) for mechanical weakening for the targeted disassembly of the casing body (4) into at least two fragments (12),

characterized,

that the enveloping body (4) is produced by means of a 3D printing process by solidifying a starting material (16) to form the enveloping body (4) and the

The predetermined breaking point (10) is formed in that the starting material (16) is not or less solidified and / or less or no starting material (16) is present than in solidified areas of the enveloping body (4), the enveloping body

(4) has a continuous inner wall (20) and / or outer wall (22) at the predetermined breaking point (10).

2. projectile casing (2) according to claim 1,

characterized,

that at least one of the fragments (12) is an active element (14) of the

Bullet is.

3. projectile casing (2) according to claim 2,

characterized,

that the entire envelope (4) can be dismantled into fragments (12) and all fragments (12) are respective active elements (14) of the projectile shell (2).

4. projectile casing (2) according to one of the preceding claims,

characterized,

that the predetermined breaking point (10) is located as an inclusion (18) between the inner wall (20) and the outer wall (22) of the enveloping body (4).

5. projectile casing (2) according to one of the preceding claims,

characterized,

that the starting material (16) is a loose starting material (16).

6. projectile casing (2) according to one of the preceding claims,

characterized,

that at the predetermined breaking point (10), at least in the longitudinal direction (30) of the enveloping body (4), its wall thickness (d) has a non-decreasing or non-increasing course between the solidified edges (26) surrounding the predetermined breaking point (10).

7. projectile casing (2) according to claim 6,

characterized,

that the wall thickness (d) has a constant course between the solidified edges (26).

8. projectile casing (2) according to one of claims 6 to 7,

characterized,

that the wall thickness (d) in the longitudinal direction (30) of the entire enveloping body (4) has a non-decreasing or not increasing or constant course.

9. projectile casing (2) according to one of the preceding claims,

characterized,

that the wall thickness (d) in the circumferential direction (28) of the enveloping body (4) is constant at at least one longitudinal position of the enveloping body (4).

10. projectile casing (2) according to claim 9,

characterized,

that the wall thickness (d) is constant at all longitudinal positions of the enveloping body (4).

11. A method for producing a projectile casing (2) according to one of the

previous claims, in which - the starting material (16) is provided,

- The enveloping body (4) is produced by means of a 3D printing process by solidifying the starting material (16) to form the enveloping body (4),

- The at least one predetermined breaking point (10) is formed in the enveloping body (4) by there the starting material (16) is not solidified or less or less or no starting material (16) is introduced into the enveloping body (4) than in solidified areas The envelope body (4) is produced at the predetermined breaking point (10) with a continuous inner wall (20) and / or outer wall (22).