Projectile and method for ejecting sub-projectiles of a projectile
Patent Information
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- RWM SCHWEIZ
- Filing Date
- 2025-11-13
- Publication Date
- 2026-07-30
Smart Images
Figure EP2025082948_30072026_PF_FP_ABST
Abstract
Description
[0001] Projectile and method for ejecting subprojectiles from a projectile
[0002] The invention relates to a projectile with the features of the preamble of claim 1 and a method for ejecting subprojectiles from a projectile. The present invention relates in particular to projectiles designed as medium-caliber projectiles.
[0003] These projectiles consist of a casing, a firing mechanism, an explosive charge, and several subprojectiles. The subprojectiles are arranged in a cavity formed by the casing. The subprojectiles can be ejected to engage the target by detonating the explosive charge via the firing mechanism.
[0004] In recent years, it has become clear that the active defense of close-range airspace with guns and the associated medium-caliber ammunition is a key element in securing vital air superiority. Effectively engaging a flying target requires high precision in the medium-caliber projectiles and efficient delivery of smaller payloads, in this case consisting of heavy metal sub-projectiles. These sub-projectiles are the aforementioned sub-projectiles. The sub-projectiles are carried as payload within the casing of the medium-caliber projectile and are ejected by controlled rupture of the casing—namely, by detonating the explosive charge—ideally at an optimal effective range from the target aircraft. This allows them to form a cloud of sub-projectiles after ejection, increasing the likelihood of hitting the target.
[0005] From EP 0 698 774 A1 a projectile is known whose projectile casing has a wave-shaped inner wall with wave crests and wave troughs adjacent to the cavity.
[0006] A known disadvantage of ejecting subprojectiles from projectile casings, e.g., from projectile casings with a wavy inner wall, is that the rupture of the projectile casings is not always exactly reproducible, and thus the subprojectile cloud can have arbitrary geometries, which accordingly leads to a reduced probability of a hit.
[0007] To meet these challenges, various systems have been developed that, for example, allow for influencing the ejection from the projectile casing through the specific arrangement of sub-bodies. Other systems have indentations in the projectile casing that allow the casing to rupture and open simultaneously at the same point everywhere. In this way, the sub-bodies are released ubiquitously and at once.
[0008] Document US 9,423,226 B2 discloses a projectile with a casing containing a payload of subprojectiles that can be released upon detonation. The projectile has a front warhead and a rear base containing a fuse with a detonator and a detonation relay. The inner casing has a hexagonal profile that stabilizes the subprojectiles in their cylindrical columns and allows them to rotate with the projectile. A hexagonal piston separates the detonation relay from the payload, stabilizing the rotation and preventing gyroscopic instabilities. Upon activation, the detonator ignites the relay, generating a shock wave that drives the piston forward, advancing the payload and severing a predetermined breaking point in the warhead, thus releasing the subprojectiles.This mechanism utilizes a simple detonation shock wave and requires no additional seals, thus increasing the projectile's stability and reliability. It features a hexagonal inner payload chamber within the projectile casing. The six rounded corners of the hexagon provide a notch effect, which ultimately aids the opening action. Additionally, grooves extending across the entire cylindrical area further enhance the opening process.
[0009] The disadvantage of the projectile disclosed in US 9,423,226 B2 is that the internal geometry shown here is designed to achieve a maximum number of subbodies rather than an optimal point of failure. Each subbody fits precisely into a longitudinal groove in the projectile casing. Furthermore, additional machining operations are required to mill the grooves and the hexagon into the projectile casing, thus increasing the labor involved in manufacturing the projectile.
[0010] Document US 11 725918 B2 describes a cylindrical payload container for a projectile / bullet, containing at least two subprojectiles designed to create a horizontal scatter pattern. The subprojectiles are arranged in one or more parallel lines and may be stacked in layers. The number of subprojectiles varies depending on the intended use and target, from 2 to 1000. The stacked arrangement allows multiple payload containers to be shifted relative to each other to create a horizontal scatter cone. By creating an angle between the payload containers, a controlled scatter pattern can be achieved, as the rotation of the projectile during release aligns the subprojectiles in a desired direction. The subprojectiles are made of various materials, such as hard or heavy metals, and can have different shapes (e.g., rods, spheres, hexagons).The (overall) projectile is rotationally stabilized and includes an elongated cavity for the payload. A sensor can trigger a detonator, subsequently ejecting the subprojectiles. The layer arrangement and the angle between the payload containers determine the horizontal dispersion, which is suitable for targets located on a horizontal plane, such as ground or surface targets. The payload container can be formed by a disc-shaped support. This ensures that the subprojectiles are ejected uniformly and in a defined deployment pattern.
[0011] A clear disadvantage of the US 11 725 918 B2 is the use of an additional mounting bracket. This design inherently reduces the payload capacity, meaning fewer subprojectiles can be carried.
[0012] The invention is therefore based on the objective of designing and / or further developing the projectile and the method for ejecting subprojectiles from a projectile in such a way that the disadvantages of the prior art are avoided, or at least reduced, in particular where the precision of the projectile and / or the precision of the ejection of the subprojectiles from the projectile is improved.
[0013] This problem underlying the invention is now initially solved by a projectile with the features of claim 1.
[0014] One aspect of the invention is essentially that the projectile casing comprises a light metal, in particular aluminium or magnesium, and / or a composite material, preferably consisting of a plastic and a light metal, and / or is made of a light metal, in particular aluminium or magnesium, or of a composite material, preferably consisting of a plastic and a light metal.
[0015] Thus, the projectile has a low weight in its radially outer region. Due to the lightweight metal casing, the weight distribution drops off sharply from the projectile axis in the radial direction towards the outer circumference of the casing. This results in improved flight stability and therefore higher projectile accuracy, especially when it is a spin-stabilized projectile. Preferably, the casing is thin-walled to improve the ratio of payload, namely the mass of the subprojectiles, to the total mass of the projectile. This also increases the projectile's operational value. The area of the casing's cavity with the corrugated inner wall is simultaneously the payload area of the projectile, in which the subprojectiles are stacked and / or poured. The corrugated inner wall ensures that the subprojectiles are packed tightly.The subprojectiles are arranged within the cavity / payload area of the projectile, minimizing the gaps between them and the inner wall. This specific design of the inner wall creates an anti-rotation mechanism between the individual subprojectiles and the projectile shell. Due to the corrugated inner wall, the material thickness of the shell varies, creating predetermined breaking points in the areas of the shell with the thinnest walls. The combination of lightweight metal, anti-rotation mechanism, predetermined breaking points, and / or dense packing results in improved ejection of the subprojectiles with enhanced precision.
[0016] Advantageously, the projectile casing has a high-strength and / or impact-resistant aluminum alloy and / or is made of a high-strength and / or impact-resistant aluminum alloy.
[0017] High-strength aluminum is susceptible to brittle fracture, especially more so than pure aluminum or steel. This apparent disadvantage is used here as an advantage, since even the relatively rounded wave shapes of the crests and troughs of the inner wall of the projectile casing provide sufficient notch effect to ensure that the projectile casing can be optimally and reproducibly ruptured after detonation of the explosive charge by the firing mechanism.
[0018] It may be advantageous if the projectile casing has an aluminum alloy with a mass fraction of aluminum of 86% to 98%, in particular of 87.17% to 97.10%, and / or is made of an aluminum alloy with a mass fraction of aluminum of 86% to 98%, in particular of 87.17% to 97.10%.
[0019] Such aluminum alloys are readily available on the market at favorable prices. Furthermore, they can be easily engineered to possess the desired properties, particularly the desired susceptibility to brittle fracture.
[0020] It can be advantageous if the projectile casing is made of an aluminum alloy of type 7075, 7050, 7020 and / or 6082 and / or is manufactured from an aluminum alloy of type 7075, 7050, 7020 and / or 6082. It can be advantageous if the projectile casing is made of an aluminum alloy of type 7075 T6R, 7075 T6, 7075 T8, 7075 T651Y, 7075 T7351Y, 6082 T4 and / or 6082 T6 and / or is manufactured from an aluminum alloy of type 7075 T6R, 7075 T6, 7075 T8, 7075 T651Y, 7075 T7351Y, 6082 T4 and / or 6082 T6.
[0021] Such aluminum alloys are characterized by a desired high strength and a desired low density. An aluminum alloy of type 7075 is particularly preferred. Here, grade T6 is of particular interest, i.e., an aluminum alloy of type 7075 T6.
[0022] According to an advantageous embodiment of the projectile, the wave crests are convex and the wave troughs are concave. Preferably, the cross-sections of the wave crests and / or the wave troughs have consistent shapes in a direction parallel to the projectile axis.
[0023] Preferably, the areas of the wave crests and / or wave troughs extend essentially parallel to the floor axis.
[0024] This further improves the support of the subprojectiles. Furthermore, aligning the axes of the subprojectiles parallel to the projectile axis during the filling of the projectile casing is facilitated.
[0025] Furthermore, the wave troughs are preferably formed by means of recesses that are eccentric in cross-section and circular sector-shaped.
[0026] Such wave troughs can be produced particularly easily and with little effort, e.g. using a drilling or milling process.
[0027] It can be advantageous to provide 3 to 21 wave troughs, for example 10 to 14 wave troughs, in particular 12 wave troughs.
[0028] With so many corrugations, a specific, desired variation in the wall thickness of the projectile casing is achieved. This variation is significantly less than, for example, in a cavity with a hexagonal cross-section or with considerably fewer corrugations. This specific variation in wall thickness results in a substantially constant stress within the projectile casing during rotational acceleration upon firing. Ultimately, this leads to greater precision and better material utilization.
[0029] Preferably, the moment of inertia of the projectile casing is between 10% and 65%, and in particular between 10% and 60%, of the moment of inertia of the entirety of the subprojectiles.
[0030] This is especially true when the projectile casing completely supports or encloses all the subprojectiles or the stack of subprojectiles. Therefore, the projectile can be accelerated particularly well upon firing without reducing the mass of the subprojectiles as a whole.
[0031] According to a preferred embodiment of the projectile, the subprojectiles are cylindrical in shape.
[0032] Thus, the subprojectiles are easy to manufacture. The subprojectiles preferably contain a heavy metal and / or are made of a heavy metal. The density of the subprojectiles is preferably between 14 g / cm³. 3 up to 19.3 g / cm³ 3 .
[0033] According to another embodiment of the projectile, the axes of the subprojectiles lie essentially parallel to a projectile axis.
[0034] Thus, good alignment towards the target to be combated is possible when ejecting the subprojectiles.
[0035] Advantageously, the ignition mechanism includes a delay fuse and / or is designed as a delay fuse. In one embodiment, the ignition mechanism includes a proximity fuse and / or is designed as a proximity fuse.
[0036] The design of the projectile with a delay fuse has the particular advantage that the deployment of subprojectiles before impact with the target can be initiated using simple means.
[0037] The problem underlying the invention is also solved by a method according to claim 14. One aspect of the invention then essentially lies in a method for ejecting subprojectiles of a previously described projectile, wherein the subprojectiles are ejected for target engagement by detonating the explosive charge by means of the ignition mechanism, wherein the projectile casing, comprising a light metal, in particular aluminium or magnesium, and / or a composite material, preferably consisting of a plastic and a light metal, opens during or for the ejection of the subprojectiles.
[0038] With such a method, the precision of the projectile and the precision of the ejection of the subprojectiles from the projectile are improved.
[0039] There are now numerous possibilities for advantageously designing and further developing the projectile according to the invention and the method according to the invention for ejecting subprojectiles of such a projectile. Reference may first be made to the claims subordinate to claim 1. In the following, preferred embodiments of the projectile according to the invention and the method according to the invention for ejecting subprojectiles of such a projectile will be explained and described in more detail with reference to the drawing and the accompanying description. The drawing shows:
[0040] Fig. 1 shows a schematic representation of an embodiment of the projectile in a side view, partly in section, and
[0041] Fig. 2 shows a schematic representation of the embodiment of the projectile from Fig. 1 in a sectional view along line AA.
[0042] Figures 1 and 2 each show a projectile 1 with a projectile casing 2, a firing mechanism 3, an explosive charge 4, and several subprojectiles 6. The subprojectiles 6 are arranged in a cavity 5 formed by the projectile casing 2. The subprojectiles 6 can be ejected for target engagement by detonating the explosive charge 4 via the firing mechanism 3. Adjacent to the cavity 5, the projectile casing 2 has a corrugated inner wall 7 with crests 8 and troughs 9. This corrugated inner wall 7 predetermines the arrangement of the subprojectiles 6 to a certain extent, thus making it less random. The cavity 5 is also referred to as the payload chamber, in which case the subprojectiles 6 constitute a payload intended to impact a target. Specifically, this is a medium-caliber projectile with a caliber of 20 to 35 millimeters.The first projectile is primarily used for air defense, i.e., for combating flying objects such as drones, missiles or aircraft.
[0043] The projectile casing 2 comprises a light metal, in particular aluminum, and / or is made of a light metal, in particular aluminum. Specifically, the density of the projectile casing 2 is less than 5.0 g / cm³. 3 , which is particularly lower than the density of steel. Thus, the mass distribution of the projectile 1 decreases sharply radially outwards from its projectile axis L through the projectile casing 2. In other words, the mass of the projectile 1 is concentrated around its projectile axis L. This allows for high precision of the projectile 1, especially if it is a spin-stabilized projectile 1. The projectile 1 is preferably designed as a spin-stabilized projectile 1.
[0044] The projectile casing 2 comprises a high-strength and / or impact-resistant aluminum alloy and / or is made of a high-strength and / or impact-resistant aluminum alloy. The tensile strength of the aluminum alloy preferably has values greater than 530 N / mm². 2 on.
[0045] The projectile casing 2 has an aluminum alloy with a mass fraction of aluminum of 86% to 98%, in particular of 87.17% to 97.10%, and / or is made of an aluminum alloy with a mass fraction of aluminum of 86% to 98%, in particular of 87.17% to 97.10%.
[0046] The projectile casing 2 is made of an aluminum alloy of type 7075, 7050, 7020 and / or 6082 and / or is manufactured from an aluminum alloy of type 7075, 7050, 7020 and / or 6082. The aforementioned aluminum mass fractions are achieved in such aluminum alloys.
[0047] The projectile casing 2 is made of an aluminum alloy of type 7075 T6R, 7075 T6, 7075 T8, 7075 T651Y, 7075 T7351Y, 6082 T4 and / or 6082 T6 and / or is manufactured from an aluminum alloy of type 7075 T6R, 7075 T6, 7075 T8, 7075 T651Y, 7075 T7351Y, 6082 T4 and / or 6082 T6. These types represent special versions of the aforementioned alloys, e.g., special grades of these alloys, which are designated with the corresponding suffixes, e.g., T4 or T6. In principle, all age-hardenable aluminum alloys can be used. The use of other aluminum alloys is also conceivable, as long as the desired properties, especially regarding strength and / or impact toughness, are achieved.
[0048] The wave crests 8 are convex and the wave troughs 9 are concave. The wave crests 8 and the wave troughs 9 alternate. Two wave troughs 9 border each wave crest 8. Two wave crests 8 can border each wave trough 9. The surfaces of the wave crests 8 and / or wave troughs 9 extend substantially parallel to the projectile axis L. "Substantially" in this context means that deviations of up to 10° from these parallel arrangements are permissible. The curvature of at least a portion of the wave crests 8 and / or wave troughs 9 is less than the curvature of a circumferential surface of the subprojectiles 6. Wave crests 8 project into the cavity 5 of the projectile 1 formed by the projectile casing 2. Wave troughs 9 are formed as recesses in the projectile casing 2 that enlarge this cavity 5.
[0049] The wave troughs 9 are formed by means of sector-shaped, eccentric recesses in cross-section. Six wave troughs 9 and three wave crests 8 are provided. The cavity 5 is preferably first produced by means of a drill or milling cutter rotating parallel to the projectile axis L, wherein the wave troughs 9 are subsequently produced by means of a smaller diameter drill or milling cutter rotating parallel to the projectile axis L, in particular by moving it perpendicular to the projectile axis L. The reduced wall thickness of the projectile casing 2 adjacent to the wave troughs 9 forms a predetermined breaking point for opening the projectile casing 2 upon detonation of the explosive charge 4.
[0050] In this embodiment, a total of subprojectiles 6 are accommodated in the payload chamber 16. The subprojectiles 6 each touch three, four, five, or six adjacent subprojectiles 6 and are arranged such that the threefold rotational symmetry of the arrangement of the subprojectiles 6 is maintained unchanged.
[0051] In this embodiment, the payload chamber is adapted to the arrangement of the subprojectiles 6 such that its inner wall 7 abuts the twelve outer subprojectiles 6. Its base, by way of example, essentially has the shape of an equilateral triangle, with the vertices bent radially inwards towards the longitudinal axis and abutting three of the outer subprojectiles. Two troughs 9 and one crest 8 are formed at each vertex of the triangle. The moment of inertia of the projectile casing 2 is between 10% and 65%, particularly between 10% and 60%, of the moment of inertia of all the subprojectiles 6. Such moment of inertia values are made possible, in particular, by the fact that the projectile casing 2 comprises a light metal, especially aluminum, and / or is made of a light metal, especially aluminum.The proportion of the payload, namely the mass of the entirety of the subprojectiles 6, is thus increased compared to the total mass of the projectile 1.
[0052] The subprojectiles 6 are cylindrical. Alternatively, subprojectiles of other shapes, e.g., angular or round, could also be provided. Preferably, all subprojectiles 6 have the same shape. The axes of the subprojectiles 6 are essentially parallel to a projectile axis L, particularly if the subprojectiles 6 are cylindrical. "Essentially" in this context means that deviations of up to 10° from these parallel arrangements are permissible. It would also be conceivable to arrange the subprojectiles chaotically, i.e., as loose material within the projectile casing, in which case different angles would be formed between the axis of each subprojectile and the projectile axis. The subprojectiles 6 are preferably arranged in several rows, with the axes of the subprojectiles 6 in each row forming essentially a straight line parallel to the projectile axis L.Furthermore, the end faces of adjacent subprojectiles 6 lie perpendicular to the projectile axis L, preferably in planes oriented perpendicular to the projectile axis L.
[0053] The ignition mechanism 3 has a delay fuze and / or is designed as a delay fuze. The delay fuze allows the explosive charge 4 to be detonated after a specific travel time of the projectile 1 following its launch from a gun barrel. It is also conceivable that the ignition mechanism 3 has a distance fuze and / or is designed as a distance fuze, so that the explosive charge 4 can be detonated at a specific distance from the target. Even when using the delay fuze, the aim is to eject the subprojectiles 6 before they reach the target.
[0054] In a method for ejecting subprojectiles 6 of the projectile 1, the subprojectiles 6 are ejected for target engagement by detonating the explosive charge 4 via the ignition mechanism 3, whereby the projectile casing 2, which comprises a light metal, in particular an aluminum alloy, opens during or for the ejection of the subprojectiles 6. This opening occurs uniformly and is easily reproducible even with different projectiles 1 of the same type, so that specific patterns of subprojectile cloud formations 6 are generated after their ejection. These clouds represent the totality of the trajectories of the subprojectiles 6.
[0055] The projectile 1 described herein and the method for ejecting subprojectiles 6 of such projectiles 1 enable, in particular, the successful active defense of close airspace with guns equipped with barrels and the securing of air superiority. Preferably, the projectiles 1 are fired from mobile and / or stationary air and / or tank guns, especially those with high elevation. Reference numerals list
[0056] 1 floor
[0057] 2-shell
[0058] 3 Ignition mechanism
[0059] 4 explosive charges
[0060] 5 Cavity
[0061] 6 subprojectiles
[0062] 7 Interior wall
[0063] 8 wave crests
[0064] 9 wave troughs
[0065] L floor axis
Claims
Patent claims 1. Projectile (1) comprising a projectile casing (2), an ignition mechanism (3), an explosive charge (4), and several subprojectiles (6), wherein the subprojectiles (6) are arranged in a cavity (5) formed by the projectile casing (2), wherein the subprojectiles (6) can be ejected for target engagement by detonating the explosive charge (4) by means of the ignition mechanism (3), wherein the projectile casing (2) has a corrugated inner wall (7) adjacent to the cavity (5) with wave crests (8) and wave troughs (9), characterized in that the projectile casing (2) comprises a light metal, in particular aluminium or magnesium, and / or a composite material, preferably consisting of a plastic and a light metal, and / or is made of a light metal, in particular aluminium or magnesium, or of a composite material, preferably consisting of a plastic and a light metal.
2. Projectile (1) according to claim 1, characterized in that the projectile casing (2) comprises a high-strength and / or impact-resistant aluminium alloy and / or is made of a high-strength and / or impact-resistant aluminium alloy.
3. Projectile (1) according to claim 1 or 2, characterized in that the projectile casing (2) comprises an aluminum alloy with a mass fraction of aluminum of 86% to 98%, in particular of 87.17% to 97.10%, and / or is made of an aluminum alloy with a mass fraction of aluminum of 86% to 98%, in particular of 87.17% to 97.10%.
4. Projectile (1) according to one of the preceding claims, characterized in that the projectile casing (2) comprises an aluminum alloy of type 7075, 7050, 7020 and / or 6082 and / or is made of an aluminum alloy of type 7075, 7050, 7020 and / or 6082.
5. Projectile (1) according to claim 4, characterized in that the projectile casing (2) comprises an aluminum alloy of type 7075 T6R, 7075 T6, 7075 T8, 7075 T651 Y, 7075 T7351 Y, 6082 T4 and / or 6082 T6 and / or is made of an aluminum alloy of type 7075 T6R, 7075 T6, 7075 T8, 7075 T651 Y, 7075 T7351 Y, 6082 T4 and / or 6082 T6.
6. Projectile (1) according to one of the preceding claims, characterized in that the wave crests (8) are convex and the wave troughs (9) are concave.
7. Projectile (1) according to one of the preceding claims, characterized in that the surfaces of the wave crests (8) and / or wave troughs (9) extend substantially parallel to the projectile axis (L).
8. Floor (1) according to one of the preceding claims, characterized in that the wave troughs (9) are formed by means of recesses in cross-section that are eccentric, circular sector-shaped.
9. Floor (1) according to one of the preceding claims, characterized in that 3 to 21 wave troughs (9), for example 10 to 14 wave troughs (9), in particular 12 wave troughs (9), are provided.
10. Projectile (1) according to one of the preceding claims, characterized in that a value of the moment of inertia of the projectile shell (2) is between 10% and 65%, in particular between 10% and 60%, of the value of the moment of inertia of the entirety of the subprojectiles (6).
11. Projectile (1) according to one of the preceding claims, characterized in that the subprojectiles (6) are cylindrical in shape.
12. Projectile (1) according to one of the preceding claims, characterized in that the axes of the subprojectiles (6) are substantially parallel to a projectile axis (L).
13. Projectile (1) according to one of the preceding claims, characterized in that the ignition mechanism (3) has a delay fuze and / or is designed as a delay fuze.
14. Method for ejecting subprojectiles (6) of a projectile (1) according to one of the preceding claims, wherein the subprojectiles (6) are ejected for target engagement by igniting the explosive charge (4) by means of the ignition mechanism (3), wherein the projectile casing (2) comprising a light metal, in particular aluminium or magnesium, and / or a composite material, preferably consisting of a plastic and a light metal, opens during or for the ejection of the subprojectiles (6).