Protection system

Abstract

The invention relates to a protection system (1) for a military vehicle, comprising at least one ballistic protection element (2) and at least one fastening system (10), which has a threaded boss (4) that can be arranged on the military vehicle and extends at least partially into a recess (3) of the ballistic protection element (2), a threaded bolt (5) screwed into the threaded boss (4) and a fastening element (6) clamped against the ballistic protection element (2) via the threaded bolt (5), wherein the threaded bolt (5) and the fastening element (6) bear against each other via curved clamping surfaces (5.1, 6.1).

Description

[0001] The present invention relates to a protection system for a military vehicle, comprising at least one ballistic protection element and at least one fastening system, which includes a threaded boss that can be arranged on the military vehicle and extends at least partially into a recess of the ballistic protection element, a threaded bolt screwed into the threaded boss, and a fastening element clamped against the ballistic protection element via the threaded bolt. A further aspect of the invention is a military vehicle with at least one such protection system.

[0002] Protective systems come in a wide variety of forms and are used particularly in the military, police, and other security-relevant sectors. Their primary purpose is to protect the object being protected from various violent threats, such as firearms, mines, or other explosive devices. Military land vehicles, such as wheeled or tracked combat vehicles, typically have one or more protective systems. Functionally, these systems are designed to ensure the operational capability of the protected vehicle under hostile threat, which is why they primarily protect drive systems and components. Furthermore, the protective systems can safeguard the crew and equipment or cargo mounted on or inside the vehicle. Such protective systems can be used not only on land vehicles but also on military watercraft and aircraft.

[0003] Such protection systems often incorporate at least one ballistic protection element. This element is frequently designed to withstand ballistic impacts for a certain period of time. This protects the areas behind the ballistic protection element from ballistic impacts. Ballistic protection elements are available in a wide variety of designs and materials and are selected in practice, particularly considering the actual threat level expected, to suit the area of ​​the military vehicle requiring protection. For example, ballistic protection elements with a higher protection level are typically used to protect manned areas of a military vehicle or to protect drive components.

[0004] The ballistic protection elements, often plate- or panel-like, are typically attached to the military vehicle via a mounting system. This system usually allows for the precise positioning of the ballistic protection elements in their designated locations on the vehicle and ensures their reliable stability under the often harsh and adverse operating conditions. Frequently, the mounting system is also designed for the ballistic protection elements to be detachable, for example, to allow for easy replacement.

[0005] The mounting system is often multi-part and typically includes a threaded stud that can be attached to the military vehicle. The threaded stud is usually secured to the vehicle via a connecting element and often comprises a raised section of material with a thread, usually an internal thread.

[0006] Traditionally, a threaded bolt is screwed into the thread of the threaded boss. A separate fastening element can often be clamped or secured against the ballistic protection element via this threaded bolt. By screwing the threaded bolt, which is often designed as a fastening screw, into the threaded boss, a clamping force can be applied to the ballistic protection element via the fastening element.

[0007] Such protection systems are generally known in various forms from the prior art, cf. for example DE 10 2010 018 486 A1 or EP 3 012 571 A1, in which an additional protection module for protection against mine explosions is arranged on the hull of a military vehicle via a corresponding fastening system.

[0008] However, in practice, it has proven disadvantageous that such protective systems can fail prematurely under particularly unfavorable threat situations. The mounting system, in particular, can prove to be a weak point in the protective structure, for example, because it represents a direct connection to the vehicle and can thus allow unwanted force to be transmitted into the vehicle under fire. Especially, fire from different weapons or multiple hits in quick succession (so-called "multi-hit") can often destroy the mounting system. The failure of the mounting system usually leads to the ballistic protection element detaching from or falling off the military vehicle, which can render the entire protective system ineffective.

[0009] Against this background, the invention presents itself as Aufgabe , to specify a protection system in which the risk of failure of the fastening system, especially under polyvalent ballistic and / or explosive impact, is reduced.

[0010] This task is accomplished in a protection system of the type mentioned above by the features of claim 1. gelöst . Advantageous further training opportunities are listed in the dependent sub-claims.

[0011] The threaded bolt and the fastening element rest against each other via curved clamping surfaces, thus enabling improved force transmission. Force transmission via these curved clamping surfaces allows for a more favorable distribution and / or dissipation of the forces exerted during gunfire and / or explosions, thereby reducing stress on both the ballistic protection element and the military vehicle. This ensures that the ballistic protection element remains in place and fulfills its protective function even after repeated impacts.

[0012] An advantageous embodiment of the invention provides that the clamping surfaces adhering to each other are formed by spherical surfaces. These spherical surfaces enable a further improved and more uniform force transmission between the threaded bolt and the fastening element. In addition, the spherical surfaces can compensate for tolerances between the ballistic protection element and the surrounding components.

[0013] In this context, it is proposed that the spherical surfaces be designed as annular spherical surfaces arranged on the threaded bolt and the fastening element. Advantageous force transmission can be achieved over the entire circumference of the threaded bolt and the fastening element via these annular spherical surfaces. The annular spherical surfaces can, in particular, be arranged circumferentially on the threaded bolt and the fastening element. Alternatively, instead of fully circumferential annular spherical surfaces, they can also be designed with one or more interrupted sections. Preferably, the spherical surfaces on the threaded bolt and the fastening element are designed to correspond, especially with regard to their geometry.

[0014] Furthermore, it has proven advantageous to integrally integrate the spherical surfaces onto the threaded bolt and / or the fastener. This results in a captive design that is also easy to assemble. Due to the integral integration of the spherical surfaces onto the threaded bolt and the fastener, they are automatically aligned correctly during assembly. This integral integration also eliminates ballistic weak points that might exist between the spherical surfaces and the threaded bolt or fastener in a multi-part assembly. Additionally, an integral integration of the spherical surfaces onto the threaded bolt and the fastener can also prove advantageous from a manufacturing perspective.

[0015] Furthermore, it is proposed that the spherical surface arranged on the threaded bolt be convexly curved and / or that the spherical surface arranged on the fastener be concavely curved. This results in an advantageous force transmission that extends essentially away from the threaded bolt. Alternatively, the spherical surface arranged on the threaded bolt can also be concave and / or the spherical surface arranged on the fastener can be convexly curved. It is advantageous if the interacting concave and convex spherical surfaces have corresponding curvatures so that the spherical surfaces of the threaded bolt and the fastener can lie flush against each other.

[0016] From a design point of view, it is further preferred if the spherical surface arranged on the threaded bolt is formed in a screw-in direction between a bolt head and a bolt shank.

[0017] In this context, it has also proven advantageous if the bolt head has a drive profile, in particular an external hexagon. The drive profile allows the threaded bolt to be screwed into the threaded boss in a user-friendly manner. The clamping force required to secure the fastener against the ballistic protection element can be reliably applied via the drive profile.

[0018] An advantageous embodiment of the invention provides that the bolt shank has an external thread, without a thread relief between the spherical surface and the bolt shank. This design avoids the mechanical weakening often associated with a thread relief.

[0019] Regarding a structurally advantageous design of the threaded boss, it is proposed that it have a base section for attachment to the military vehicle and a threaded section for screwing in the threaded bolt, opposite to the screw-in direction. With such a design, the threaded boss can be secured to the military vehicle via the base section, and simultaneously the threaded bolt can be screwed into the threaded boss via the threaded section.

[0020] In this context, it is preferable if the threaded boss has a continuous bore with an internal thread extending over both the threaded section and the base section. This ensures sufficient axial thread length so that the threaded bolt can be securely screwed into the threaded boss with the required torque. A continuous bore can also offer manufacturing advantages over a non-continuous bore.

[0021] In this context, it has proven advantageous for the bore on the shaft section to have a chamfer to simplify the insertion of the threaded bolt. The chamfer can enable operators to install the threaded bolt more quickly.

[0022] It is further proposed that the outer diameter of the threaded shank be larger in the base section than in the threaded section. This results in a stepped design of the threaded shank, which can improve ease of assembly. The mechanical strength of the threaded shank can be influenced by the design of the outer diameter in the base section and / or the threaded section, and can also be adjusted to the expected loads. Furthermore, the mass of the threaded shank can also be adjusted by the design of the outer diameters in the base section and the threaded section. The larger the outer diameter of the threaded shank in the base section, the longer its circumference in this section.A larger circumference in the base section can be advantageous, for example with regard to a durable, material-bonded connection with the military vehicle, because with a larger outer diameter in the base section, a larger contact area is potentially available for creating the connection between the threaded stud and the military vehicle.

[0023] In this context, it has proven structurally advantageous if the threaded section along the screw-in axis is longer than the base section. Alternatively, the threaded section and the base section can also be essentially the same length, or the base section can be longer than the threaded section along the screw-in axis.

[0024] Furthermore, it has proven advantageous if the threaded stud can be attached to the military vehicle via a weld formed between the base section and the vehicle. A weld is generally characterized by high strength and load-bearing capacity. Preferably, the weld is a single- or multi-layer weld that can extend at least partially along the circumference of the base section. The weld can, in particular, provide a metallurgical bond between an outer surface of the military vehicle and the base section of the threaded stud. Preferably, the weld is adapted to the expected loads, especially with regard to the welding material and weld seam profile.

[0025] An advantageous embodiment of the invention provides that the recess of the ballistic protection element has a base receiving area corresponding to the base section of the threaded stud and a thread receiving area corresponding to the threaded section. With this embodiment, the ballistic protection element can be mounted in a user-friendly manner by simply placing it over the threaded stud with the recess. The stepped design of the recess of the ballistic protection element, which corresponds to the threaded stud, allows for easy positioning of the ballistic protection element relative to the threaded stud and can help to avoid positioning or mounting errors. The thread receiving area of ​​the recess, which faces outwards towards the vehicle when the ballistic protection element is mounted, has a smaller diameter than the base receiving area.On the outside, the ballistic protection element has a lesser vulnerability due to the recess than on the inside.

[0026] A preferred embodiment of the invention provides that the base section of the threaded stud has a square cross-section. A square, and in particular a rectangular, cross-section of the threaded stud can provide defined contact or bearing surfaces for the ballistic protection element. Furthermore, the weld seams of the welded joint can, in this case, run straight, at least in sections. In particular, the base section of the threaded stud can have a rectangular cross-section transverse to the screw-in axis of the threaded bolt.

[0027] In this context, it is further proposed that the base receiving area of ​​the recess for the ballistic protection element have a square cross-section corresponding to the base section of the threaded boss. This enables a positionally secure, and in particular rotationally secure, mounting of the ballistic protection element on the military vehicle.

[0028] It is further preferred if the base receiving area of ​​the recess for the ballistic protection element has a contact surface for the base section of the threaded stud. The ballistic protection element can be supported in a defined manner against the base section of the threaded stud via this contact surface. With such a design, the weight forces of the ballistic protection element can be absorbed simply and reliably by the threaded stud via the correspondingly shaped surfaces.

[0029] In a further advantageous embodiment of the invention, it is proposed that the weld joint be designed as a single-layer weld, in particular a fillet weld, which surrounds the threaded stud in its base section in a U-shape on three sides. This results in a strong, load-bearing weld joint between the threaded stud and the military vehicle. Preferably, the U-shaped weld is designed and arranged such that the flat contact of the ballistic protection element in the base section of the threaded stud is not impaired.

[0030] In this context, it is further advantageous if the ballistic protection element has a U-shaped groove in its base mounting area to accommodate the weld. The U-shaped groove can be designed to correspond to the U-shaped weld, so that the weld is received by the U-shaped groove when the ballistic protection element is mounted. Thanks to the U-shaped groove, the inner surface of the ballistic protection element can lie flush against the outer surface of the military vehicle. Furthermore, the ballistic protection element can protect the weld located in the U-shaped groove from ballistic impacts.

[0031] In this context, a particularly assembly-friendly embodiment provides that the groove ends of the U-shaped groove project beyond the threaded boss transversely to the screw-in direction. This design ensures that the contact surfaces of the recess for the ballistic protection element and the threaded boss lie flat against each other.

[0032] In an alternative embodiment of the threaded shank, it is proposed that the base section of the threaded shank have a circular cross-section. This can enable particularly simple manufacturing of the threaded shank. Furthermore, such a threaded shank can be attached to the military vehicle with particular ease of assembly via the base section with its circular cross-section, since its orientation is irrelevant due to the circular cross-section.

[0033] In this context, it is preferred if the base receiving area of ​​the recess for the ballistic protection element has a circular cross-section corresponding to the base section of the threaded stud. This results in a design that is easy to assemble. Furthermore, the corresponding cross-sectional shape of the recess and threaded stud in the base section or base receiving area prevents any undesirable weakening of the ballistic protection element.

[0034] Furthermore, it is proposed that the threaded receiving area of ​​the recess for the ballistic protection element has a contact surface for the threaded section of the threaded stud. This contact surface allows for reliable support of the ballistic protection element against the threaded stud, particularly in the vertical direction. This enables the threaded stud to absorb, for example, the weight of the ballistic protection element.

[0035] A further advantageous embodiment of the invention provides that the weld joint is designed as a multi-layer weld seam, in particular a fillet weld, completely enclosing the base section of the threaded stud. This results in a particularly stable connection between the base section of the threaded stud and the military vehicle. Furthermore, a fully circumferential, multi-layer weld seam can be produced relatively easily. The risk of manufacturing defects can also be reduced due to the multi-layer weld seam structure. Preferably, the weld joint is adapted to the expected loads, particularly with regard to the welding material and weld seam geometry.

[0036] It has proven advantageous to have the welded joint integrated into the base mounting area of ​​the ballistic protection element. This allows the ballistic protection element to be mounted flush with the military vehicle. Furthermore, in this configuration, the welded joint can be protected from ballistic impacts by the ballistic protection element. Alternatively, a circumferential groove can be provided in the base mounting area of ​​the ballistic protection element to accommodate the welded joint.

[0037] In this context, a structurally preferred embodiment provides that the threaded shank in the base section tapers towards the threaded section. Such a design can also prove to be mechanically advantageous. Furthermore, the taper allows for a preferred arrangement of the weld layers in the weld seam.

[0038] Furthermore, it can be advantageous if the fastening element is clamped against the ballistic protection element from the outside. This results in a user-friendly design, in which the fastening element can be clamped against the ballistic protection element simply and quickly by screwing the threaded bolt into the threaded boss.

[0039] In this context, it is proposed that the fastening element be disc-shaped and / or have a ballistically optimized, particularly trapezoidal, cross-section. A disc-shaped fastening element can be easily clamped against the ballistic protection element using the threaded bolt. Furthermore, the compact design of a disc-shaped fastening element proves advantageous. A ballistically optimized cross-section can serve to dissipate forces resulting from gunfire or other ballistic impacts. A preferred embodiment provides that the fastening element has a larger bearing surface on the side facing the ballistic protection element than on the opposite side, facing away from the ballistic protection element.Furthermore, a separate fastening element, independent of the threaded bolt, can prove to be flexible in its application, as different screw-in lengths of the threaded bolt can be easily achieved in this way and / or threaded bolts with different thread lengths can be used.

[0040] Another preferred embodiment provides that the fastening element is designed and arranged such that it at least partially covers the weld joint transversely to the screw-in direction of the threaded bolt. In this way, the weld joint, which generally represents a certain weak point in the protective assembly, can be protected against ballistic and / or explosive threats by means of the fastening element. Preferably, the outer diameter of the fastening element can be larger than the outer diameter of the weld joint.

[0041] A design that facilitates assembly involves the clamping surface on the fastener being shorter along the screw-in axis than the clamping surface on the threaded bolt. This ensures, for example, that the clamping surface on the fastener is in full contact with the clamping surface on the threaded bolt. Positioning or alignment errors during the installation of the ballistic protection element are largely avoided with this design.

[0042] In this context, it is further proposed that the fastening element have a cylindrical recess adjacent to the clamping surface. This recess can compensate for tolerances when attaching the ballistic protection element to the military vehicle, thus facilitating assembly. Preferably, the recess can be dimensioned such that the spherical surface of the threaded bolt does not protrude axially beyond the fastening element in the assembled state. However, the bolt head with the drive profile should preferably protrude beyond the fastening element to allow the use of a suitable tool for disassembly.

[0043] Furthermore, it is preferred if the material of the fastener has a greater toughness than the material of the threaded bolt. With such a material selection, the forces and displacements transmitted from the threaded bolt to the fastener can be compensated for by the comparatively tough material of the fastener. The energy resulting from bombardment or spattering can be at least partially absorbed by a tough material of the fastener.

[0044] Specifically, in this context, with regard to favorable energy absorption capacity, it is proposed that the material of the fastening element has an elongation at break of at least 12%, determined in a tensile test with a specimen length that is five times the specimen diameter.

[0045] Furthermore, from a materials engineering point of view, it has proven advantageous with regard to good protective effect if the material of the fastening element has an impact energy of at least 45 joules, determined in the Charpy impact bending test with V-shaped notched specimens.

[0046] Furthermore, in this context, it is proposed that, with regard to good protective effect, the material of the fastening element should have a tensile strength of at least 1,000 N / mm² and / or a 0.2% yield strength of at least 850 N / mm².

[0047] Another materially advantageous embodiment provides that the material of the threaded bolt has an elongation at break of at least 9%, determined in a tensile test with a specimen length that is five times the specimen diameter.

[0048] Furthermore, with regard to the properties of the threaded bolt, it can be advantageous if the material of the threaded bolt has an impact energy of at least 27 joules, determined in the Charpy impact bending test with V-shaped notched specimens.

[0049] Furthermore, it is proposed that the material of the threaded bolt has a tensile strength of at least 1,040 N / mm² and / or a 0.2% yield strength of at least 940 N / mm².

[0050] With regard to the effective protective effect of the ballistic protection element, it has proven preferable for the ballistic protection element to be plate-like and / or made of a composite material. Plate-like ballistic protection elements can also prove to be advantageous in terms of manufacturing and ease of handling. The shape of the ballistic protection element can be adapted to the shape of the area of ​​the military vehicle it is intended to protect. A modular design consisting of several ballistic protection elements that can be flexibly combined can also be advantageous. The choice of material can be made, in particular, with regard to the expected ballistic and / or explosive threats.

[0051] To Lösung For the aforementioned task, a military vehicle with at least one protection system is proposed, wherein the protection system is designed according to one or more of the aforementioned features. The advantages and characteristics explained in connection with the protection system result from this.

[0052] Further details of a protection system and a military vehicle according to the invention are explained below with reference to the accompanying drawings of exemplary embodiments. These drawings show, in part, a sectional view of: Fig. 1a: a perspective, partially cut-out, partial side view of a protective system; Fig. 1b: another perspective, partially cut-out, partial side view of the protective system according to Fig. 1b Fig. 2a: another perspective, partially cut-out, partial side view of another protective system; Fig. 2b: another perspective, partially cut-out, partial side view of the protective system according to Fig. 2b ; Fig. 3: a further, partial side view of two adjacent protective systems, and Fig. 4a and b: two further, partially cut, partial side views of two protective systems.

[0053] The depictions in the Fig. 1a bis 4b Figure 1 shows several embodiments of the protection systems 1 according to the invention in different views. The protection systems 1 are each arranged on a military vehicle, which can be, in particular, a military combat vehicle, such as a main battle tank or infantry fighting vehicle. Alternatively, the military vehicle can also be a watercraft or aircraft, or the protection systems 1 can be arranged on stationary military installations.

[0054] The respective protection system 1 serves to protect the military vehicle from ballistic threats, in particular from multi-faceted ballistic threats caused by various types of ammunition, projectiles, fragments, explosions, or other ballistic threats. For example, the protection system 1 can be located in the running gear area of ​​a tracked military vehicle. The protection system 1 has a modular design and comprises one or more ballistic protection elements 2, which can be configured as protection modules. Figuren 1a bis 2b Only one ballistic protection element 2 is shown in each illustration. The ballistic protection element 2 is attached to the outside of the military vehicle. The ballistic protection element 2 is essentially plate-like, but can also have a different shape. In particular, the ballistic protection element 2 can be adapted to the shape of the area of ​​the military vehicle it is intended to protect. The ballistic protection element 2 is made of an armor material, in particular, it can be made of a composite material. Suitable metallic, ceramic, or plastic materials, for example, can be used as components of the composite.

[0055] The individual ballistic protection elements 2 are attached to the military vehicle via one or more fastening systems 10. For this purpose, the ballistic protection elements 2 each have at least one continuous recess 3 which interacts with the components of the respective fastening system 10. The following section describes, with reference to the illustration in Fig. 1a First, the basic structure of the fastening system 10 is explained, before two different design variants of the fastening system 10 for single or multiple attachment of ballistic protective elements 2 are discussed.

[0056] The fastening system 10 includes a threaded stud 4, see below. Fig. 1a The threaded stud 4 is attached to an outer surface of the military vehicle by a weld 7. The threaded stud 4 is a one-piece, essentially cuboid or cylindrical accumulation of material with a continuous bore 4.1. The threaded stud 4 has a rotationally symmetrical structure with respect to the insertion axis E. The bore 4.1 is provided with a continuous internal thread into which a threaded bolt 5 can be screwed along the insertion axis E in the screw-in direction R. The threaded stud 4 is welded to the military vehicle such that the bore 4.1 extends essentially perpendicularly or obliquely outwards from the military vehicle.

[0057] The threaded boss 4 has a base section A 1 and a threaded section A 2 adjoining it, contrary to the screwing direction R, cf. Fig. 1a and 2aIn the base section A1, the threaded boss 4 is attached to the military vehicle via the weld 7. The threaded section A2 serves for screwing in the threaded bolt 5 and carries the corresponding internal thread. However, the continuous internal thread of the boss bore 4.1 extends not only over the threaded section A2, but also over the base section A1. As can be seen in the illustrations in Fig. 1a and 2a As can be seen, the threaded section A2 is axially longer along an insertion axis E than the base section A1. The outer diameter of the threaded shank 4 is larger in the base section A1 than in the threaded section A2. Therefore, the threaded shank 4 has a substantially T-shaped cross-sectional contour transverse to the insertion axis E, which is well illustrated in the figures. Fig. 1a bis 2b is recognizable.

[0058] Furthermore, the fastening system 10 includes a threaded bolt 5, see also Fig. 1a The threaded bolt 5 is designed in the manner of a screw and comprises a bolt head 5.2 and a bolt shank 5.3. The bolt head 5.2 has a larger diameter than the bolt shank 5.3. The essentially cylindrical bolt shank 5.3 is provided with an external thread which corresponds to the internal thread of the threaded stud 4. The threads of the threaded stud 4 and the threaded bolt 5 can therefore, in particular, have the same diameter and the same thread pitch. The bolt head 5.2 has a drive profile, which, according to the illustration in Fig. 1a und b The drive profile is designed as an external hexagon. The threaded bolt 5 can be screwed into the threaded boss 4 using a suitable tool.

[0059] To simplify screwing in, both the bolt shaft 5.3 and the shank bore 4.1 have circumferential chamfers 8 at their ends, which serve as insertion ramps when inserting the threaded bolt 5 into the shank bore 4.1 of the threaded shank 4.

[0060] Furthermore, the fastening system 10 includes a fastening element 6. The fastening element 6 is designed as a separate fastening disc and is arranged such that it can be clamped against the ballistic protection element 2 via the threaded bolt 5 screwed into the threaded boss 4, cf. for example Fig. 1a and b. In the assembled, tensioned state, the fastening element 6 is located on the outside of the ballistic protection element 2. It is situated between the bolt head 5.2 of the threaded bolt 5 and the outer surface of the ballistic protection element 2. When the threaded bolt 5 is screwed into the threaded socket 4, a clamping force is transferred from the bolt head 5.2 to the fastening element 6 and, via this, to the ballistic protection element 2. The transferable clamping force ensures that the ballistic protection element 2 is flush with the outer wall of the military vehicle and securely positioned relative to it. The separate fastening element 6 allows it to be used independently of the screw-in length of the threaded bolt 5. Thus, ballistic protection elements 2 with different wall thicknesses and correspondingly different threaded sockets 4 and threaded bolts 5 can be used with one and the same fastening element 6.

[0061] The threaded bolt 5 and the fastening element 6 abut each other via curved clamping surfaces 5.1, 6.1. This is illustrated below in the diagrams in Fig. 1a und 1b As explained, this design allows for an advantageous flow of forces and a favorable dissipation of forces acting on the protection system 1 from the outside, such as those that can arise when the military vehicle is shot at.

[0062] The curved clamping surface 5.1 on the threaded bolt 5 and the curved clamping surface 6.1 on the fastening element 6 are formed by spherical surfaces, cf. Fig. 1a This means that the surfaces of the corresponding areas of the threaded bolt 5 and the fastening element 6 are curved in the manner of a spherical surface. The corresponding areas can be designed as spherical segments, spherical caps, or parts thereof. The spherical surface arranged on the threaded bolt 5 is positioned in the screw-in direction R in the manner of an annular circumferential collar between the bolt head 5.2 and the bolt shank 5.3, cf. Fig. 1a The spherically curved clamping surface 5.1 on the threaded bolt 5, which has a convex curvature, can also be referred to as a spherical collar. The curved clamping surface 5.1 is an integral part of the threaded bolt 5 and is thus integrally attached to it. No thread relief is provided between the curved clamping surface 5.1 of the threaded bolt 5 and the bolt shank 5.3, which has the external thread, so that any associated weakening of the protective structure can be avoided.

[0063] The curved clamping surface 6.1 of the fastening element 6, which interacts with the curved clamping surface 5.1 of the threaded bolt 5, is designed correspondingly to the curved clamping surface 5.1, cf. Fig. 1a and b. This means that the curved clamping surface 6.1 has a concave curvature, the magnitude of which essentially corresponds to the curvature of the curved clamping surface 5.1. The spherically curved clamping surface 6.1 is integrally mounted on the fastening element 6.

[0064] The abutting curved clamping surfaces 5.1, 6.1 of the threaded bolt 5 and the fastening element 6 allow axially acting forces to be dissipated radially. For example, the forces resulting from gunfire on the bolt head 5.2 can be directed radially outwards via the curved clamping surfaces 5.1, 6.1. This relieves the bolt shank 5.3 and the threaded stud 4, delaying or preventing failure of the fastening system 10, which generally leads to failure of the protective system 1.

[0065] In addition to the geometric conditions in the contact area between the threaded bolt 5 and the fastening element 6, the material pairing of the two elements is another important factor with regard to the effective protective effect of the protection system 1 for military vehicles against ballistic threats. The material of the fastening element 6 exhibits greater toughness than the material of the threaded bolt 5. This allows the fastening element 6 to compensate for acting forces and movements of the ballistic protection element 2. Preferably, the material of the fastening element 6 has an elongation at break of at least 12%, determined in a tensile test with a specimen length five times the specimen diameter.Furthermore, with regard to good resistance of the fastening element 6 to sudden ballistic impacts, it is advantageous if the impact energy of the material of the fastening element 6 is at least 45 joules, determined in the Charpy impact test with V-shaped notched specimens. To simultaneously ensure sufficient strength of the fastening element 6, it is proposed that the material of the fastening element 6 has a tensile strength of at least 1,000 N / mm² and / or a 0.2% yield strength of at least 850 N / mm².

[0066] The threaded bolt 5, on the other hand, is made of a high-strength, particularly metallic, material to withstand the applied loads and to remain securely in its intended position even under the prevailing stresses, thus holding the ballistic protective element 2 in place. The tensile strength of the material of the threaded bolt 5 should be at least 1,060 N / mm² and / or the 0.2% yield strength of the material should be at least 940 N / mm². It is advantageous if the material of the threaded bolt 5 has an elongation at break of at least 9%, determined in a tensile test with a specimen length five times the specimen diameter. Furthermore, the material of the threaded bolt 5 should preferably have an impact energy of at least 27 joules, determined in a Charpy impact test with V-shaped notches.

[0067] The following section explains how the ballistic protection element 2 is attached to the military vehicle. The figures illustrate two different concepts, which will be explained in turn. Both concepts share the characteristic of requiring a minimal number of attachment systems 10 compared to the prior art.

[0068] The ballistic protection element 2 can be attached to the military vehicle via a single or multiple attachment point. With a single attachment point, the ballistic protection element 2 is attached to the military vehicle at only one attachment point using a single attachment system 10. With a multiple attachment point, the ballistic protection element 2 is attached to the military vehicle via two or more attachment points and, accordingly, two or more attachment systems 10. The requirements for a single attachment point differ from those for a multiple attachment point, which is why the attachment systems 10 for single and multiple attachment points are also designed differently. The following section will first describe this with reference to the illustrations in Fig. 1a und b The structure and function of a single connection are explained.

[0069] If a ballistic protection element 2 is attached to the military vehicle via only one fastening system 10 at a single attachment point, there is a risk that the ballistic protection element 2 will rotate undesirably under the prevailing conditions in the field, particularly about the screw-in axis E of the threaded bolt 5. To prevent this, the threaded boss 4 and the recess 3 of the ballistic protection element 2 have suitable cross-sectional geometries that can provide anti-rotation protection for the fastening system 10 and thus for the protection element 2. These can be triangular, quadrilateral, or other polygonal cross-sectional geometries.

[0070] As this is shown in the representation in Fig. 1a As can be seen, the base section A 1 of the threaded boss 4 has a substantially rectangular cross-section along the screw-in axis E. The base receiving area B 1 of the recess 3 is designed correspondingly to the base section A 1 and also has a substantially rectangular cross-section. The diameter of the base receiving area B 1 is slightly larger than the diameter of the base section A 1 so that the base receiving area B 1 can accommodate the base section A 1 and allow for easy placement of the ballistic protection element 2 onto the threaded boss 4.Since, in the assembled state, the rectangular base section A 1 is received by the rectangular base receiving area B 1, a rotation of the ballistic protection element 2 relative to the threaded stud 4 (and thus also to the military vehicle to which the threaded stud 4 is attached via the welded connection 7) can be effectively prevented.

[0071] In the vertical direction, the ballistic protective element 2 rests on the threaded boss 4 in its base receiving area B 1 and is thereby supported, cf. Fig. 1a and b. The base receiving area B 1 of the recess 3 of the ballistic protection element 2 has a substantially flat contact surface for the base section A 1 of the threaded boss 4. The upper surface of the threaded boss 4 lies flat against the ballistic protection element 2 in the base section A 1, cf. Fig. 1a and b.

[0072] The threaded stud 4 is attached to the military vehicle via a weld 7. The weld 7 is designed as a U-shaped weld seam enclosing the threaded stud 4 in its base section A 1 on three sides, cf. Fig. 1a The three sides are the underside, as well as the right and left sides of the threaded stud 4. The U-shaped weld allows the top of the threaded stud to be available for contact with the ballistic protection element 2 in the base section A 1. Compared to a round cross-section, the rectangular cross-section of the base section A 1 allows for greater weld lengths and thus a potentially more stable connection between the threaded stud 4 and the military vehicle. As shown in the Fig. 1a und b As shown, the weld can be designed as a single-pass fillet weld. Alternatively, other weld types and / or multi-pass welds can also be used.

[0073] The ballistic protection element 2 has a U-shaped groove 9 in its base mounting area B 1 for receiving the weld seam, cf. Fig. 1a The U-shaped groove 9 accommodates the U-shaped weld. The U-shaped groove 9 allows the ballistic protection element 2 to rest against the military vehicle with a flat surface and minimal gap. The cross-sectional geometry and dimensions of the U-shaped groove 9 are adapted to the weld geometry. In the exemplary embodiment according to Fig. 1a The U-shaped groove 9 has a triangular cross-section corresponding to the single-layer fillet weld. For more extensive weld shapes or multi-layer welds, the U-shaped groove 9 can also be designed to be correspondingly larger in order to accommodate the weld.

[0074] The two groove ends 9.1 of the U-shaped groove 9 project beyond the threaded boss 4 in a direction transverse to the screw-in axis E, cf. Fig. 1a Specifically, the two groove ends 9.1 extend beyond the contact surface between the threaded boss 4 and the ballistic protection element 2, cf. Fig. 1a This enables the ballistic protection element 2 to be fully supported on the entire upper surface of the base section A 1 of the threaded boss 4. This results in reliable support for the ballistic protection element 2. Furthermore, the projection of the groove 9.1 facilitates simplified and user-friendly installation.

[0075] Contrary to the screw-in direction E, the threaded section A 2 of the threaded boss 4 adjoins the base section A 1, cf. Fig. 1a Since the threaded section A2 has a smaller outer diameter than the base section A1, a step is formed along the screw-in axis E between the threaded section A2 and the base section A1, and the threaded boss 4 has a T-shaped cross-sectional contour. The stepped transition area between the base section A1 and the threaded section A2 serves as a stop and thus as a positioning aid during the assembly of the ballistic protection element 2. The recess 3 has a contact surface for the base section A1 of the threaded boss 4. The recess 3 of the ballistic protection element 2 has a corresponding shape to the threaded boss 4, with the diameter of the base receiving area B1 being smaller than the diameter of the thread receiving area B2.The transition between sections A1, A2 of the threaded boss 4 and the transition between areas B1, B2 of the recess each have chamfers or bevels, cf. . Fig. 1a This avoids design weaknesses that can occur, for example, due to notch effects at abrupt transitions between sections or areas.

[0076] As an alternative to a single connection, as used in Fig. 1a und b As shown, the ballistic protection element 2 can also be attached to the military vehicle via multiple attachment points. Depending on the number of attachment or mounting points, the ballistic protection element 2 has several recesses 3, and a corresponding number of mounting systems 10 are used. The illustrations according to Fig. 2a und b Figures 4a and 4a show an example of a fastening system 10 for multiple connections.

[0077] Since there is no risk of unwanted rotation of the ballistic protection element 2 in a multiple connection due to the at least two fastening points, the fastening system 10 does not need to have an anti-rotation function in this respect. Therefore, the geometry of the threaded boss 4 of the multiple connection is simpler, which also makes it easier to manufacture. In particular, the base section A 1 of the threaded boss 4 does not have a four- or rectangular cross-section, but rather a substantially circular cross-section transverse to the screw-in axis E, cf. Fig. 2a and b. Due to the circular cross-section, when welding to the military vehicle, it is not necessary to take into account the rotational position of the threaded stud 4, which increases the ease of assembly.

[0078] The base receiving area B 1 of the recess 3 is designed correspondingly to the base section A 1 and accordingly also has a substantially circular cross-section. The diameter of the base receiving area B 1 is slightly larger than the diameter of the base section A 1 so that the base receiving area B 1 can accommodate the base section A 1 and allow for easy placement of the ballistic protection element 2 onto the threaded boss 4.

[0079] In the vertical direction, the ballistic protective element 2 rests on the threaded boss 4 in its threaded receiving area B 1 and is thereby supported, cf. Fig. 2a and b. The thread receiving area B 2 of the recess 3 of the ballistic protection element 2 has a contact surface for the threaded section A 2 of the threaded boss 4. The upper side of the threaded boss 4 rests against the ballistic protection element 2 in the base section A 1 in a substantially linear fashion, cf. Fig. 2a and b.

[0080] The threaded stud 4 of the multiple connection is also attached to the military vehicle via a weld 7. The weld 7 is designed as a weld seam completely enclosing the threaded stud 4 in its base section A 1, cf. Fig. 2a As in the Fig. 2a und b As shown, the weld can be designed, in particular, as a fillet weld comprising two weld passes (7.1, 7.2). Alternatively, other weld shapes and / or multi-pass welds can be used. The weld can also be intermittent for certain applications, i.e., not continuous.

[0081] The double-layer weld seam is taken up by the base mounting area B 1 of the ballistic protection element 2, cf. Fig. 2a and b. For this purpose, the diameter of the recess 3 in the base receiving area B 1 is correspondingly enlarged so that not only the base section A 1, but also the weld seam thereof, is accommodated. This ensures that the ballistic protection element 2 can lie flush against the military vehicle. Furthermore, the weld joint is protected by the ballistic protection element 2 due to this design.

[0082] According to the representations Fig. 2a und b It can also be seen that the threaded shank 4 tapers in its base section A 1 towards the threaded section A 2. This allows for the reliable production of multi-layer welded joints, as a greater overlap of the individual weld layers 7.1, 7.2 can be achieved, cf. Fig. 2a .

[0083] Contrary to the screw-in direction E, the threaded section A 2 of the threaded shank 4 also connects to the base section A 1 for multiple connection, cf. Fig. 2a Since the threaded section A2 has a smaller outer diameter than the base section A1, a step is formed along the screw-in axis E between the threaded section A2 and the base section A1, and the threaded boss 4 has a substantially T-shaped cross-sectional contour. The stepped transition area between the base section A1 and the threaded section A2, which is less pronounced than in the case of a single connection, serves as a kind of stop and thus as a positioning aid during the assembly of the ballistic protection element 2. The recess 3 of the ballistic protection element 2 has a shape corresponding to the threaded boss 4, with the diameter of the base receiving area B1 being smaller than the diameter of the thread receiving area B2. The recess 3 thus provides a contact surface for the base section A1 of the threaded boss.The transition between sections A1, A2 of the threaded boss 4 and the transition between areas B1, B2 of the recess each have chamfers or bevels, cf. . Fig. 1a This avoids design weaknesses that can occur, for example, due to notch effects at abrupt transitions between sections A1, A2 or areas B1, B2.

[0084] In both the single-connection and multi-connection protection systems 1, the geometric relationship between the threaded stud 4 and the recess 3 ensures that the weld joint 7 is protected against ballistic threats by the ballistic protection element 2. The stepped design of the threaded stud 4 and the recess 3 allows at least a certain material thickness of the ballistic protection element 2 to cover the weld joint 7 transversely to the screw-in direction R. Furthermore, the fastening element 6 provides additional ballistic protection for the weld joint 7. The diameter of the fastening element 6 is selected such that the weld joint 7 is at least partially covered by the fastening element 6 transversely to the screw-in direction R (see figure). Fig. 1a bis 2b .

[0085] As further shown in the representations in Fig. 1a bis 2b As can be seen from the diagram, the design of the fastening element 6 allows for the compensation of weak points in the protective structure. The cross-section of the disc-shaped fastening element 6 is ballistically optimized. Specifically, a substantially trapezoidal cross-sectional shape is provided, cf. Fig. 1a The annular surface of the underside of the fastening element 6, which is in contact with the ballistic protection element 2 and thus serves to transmit the clamping force to the ballistic protection element 2, is larger than the annular surface of the opposite upper side of the fastening element 6. The outer diameter of the fastening element 6 is also larger on its underside facing the ballistic protection element 2 than on its opposite upper side. The fastening element 6 thus covers the gap between the ballistic protection element 2 and the threaded boss 4 transversely to the screw-in direction R. Any further ballistic vulnerabilities that may exist can also be closed by a suitable design of the fastening element 6.

[0086] The spherical clamping surface 6.1 of the fastening element 6 is formed on its inner diameter, cf. Fig. 1a Along the screw-in axis E, the clamping surface 6.1 is axially shorter than the corresponding clamping surface 5.1 of the threaded bolt 5.1. Due to the different axial lengths of the clamping surfaces 5.1 and 6.1, tolerance compensation during assembly is possible. Minor geometric deviations of the elements of the fastening system 10, such as diameter variations of the fastening element 6 and / or the threaded bolt 5, can thus be compensated for. Furthermore, positional compensation under fire is also possible in this way.

[0087] A cylindrical recess is provided axially adjacent to the clamping surface 6.1 opposite the screw-in direction R in the fastening element 6, see also Fig. 1a The cylinder countersink also serves to compensate for tolerances when screwing the threaded bolt 5 into the threaded boss 5. This ensures that the bolt head 5.2, when screwed in, always has essentially the same protrusion relative to the fastening element 6.

[0088] The representations according to Fig. 3 Figures 4a and 4b show different schematic and partially cutaway frontal views of the plane of the ballistic protection element 2.

[0089] In Fig. 3 Rear views of two ballistic protection elements 2, which are mounted on the exterior of the military vehicle, are shown. In the left part of the Fig. 3 is a fastening point of a single connection and in the right part of the Fig. 3 A fastening point for a multiple connection is shown. In the left part of the image... Fig. 3 It can be seen that the base section A 1 of the threaded boss 4 has a substantially rectangular, slightly trapezoidal cross-sectional shape, thereby providing a locking mechanism against unwanted rotation of the ballistic protective element 2 about the area shown in the illustration. Fig. 3 The screw-in axis E, extending transversely to the plane of representation, can be avoided. Furthermore, the essentially U-shaped groove 9 of the ballistic protection element 2 is visible, which surrounds the base section A 1 of the threaded bolt 4 on three sides and serves to receive the also U-shaped weld seam of the welded joint 7, so that the ballistic protection element 2 can lie flush against the outside of the military vehicle. In the exemplary embodiment, the groove ends 9.1 project beyond the Fig. 3 the threaded boss 4 on the sides arranged to the left and right of the screw-in axis E. It can also be seen that the ballistic protection element 2 rests flat on the top of the threaded boss 4 and is thus supported by the fastening system 10.

[0090] In the representation according to Fig. 4a On the one hand, the external hexagon drive profile of the bolt head 5.2 of the threaded bolt 5 is recognizable. On the other hand, an embodiment is recognizable in which the groove ends 9.1 of the groove 9 do not project beyond the threaded boss 4 in this case.

[0091] In the right part of the image of Fig. 3 as in Fig. 4b The circular cross-sectional shape of the base section A 1 of a threaded stud 4 of a multiple connection is visible. As the schematic representation illustrates, the weld joint 7 in this type of fastening system 10 is formed around the circular base section A 1 of the threaded stud 4. Since at least two such fastening points, spaced apart from each other, are always provided in the multiple connection, this ensures that the connection is secured against rotation.

[0092] It is also in the right part of the image. Fig. 3 It can be seen that a circular groove 9 is provided in the area of ​​the recess 3 of the ballistic protection element 2, which receives the weld joint 7. It can also be seen that the ballistic protection element 2 does not rest on the threaded boss 4 in the case of multiple connections. As previously shown with reference to the illustrations in Fig. 2a und b As explained, the contact surfaces between the ballistic protection element 2 and the threaded stud 4 are located in the threaded section A 2 or the threaded receiving area B 2 in this case. Alternatively or additionally, the required holding force for holding the ballistic protection element 2 can be applied via the clamping force, which can be transmitted via the threaded bolt 5 and the fastening element 6.

[0093] In the representation according to Fig. 4b The external hexagon drive profile of the bolt head 5.2 of the threaded bolt 5 is again recognizable. The threaded bolt 5 and also the fastening element 6 can be identical regardless of whether it is a single or multiple connection, and are therefore usable for both variants.

[0094] The following describes a method for attaching a protection system 1 comprising at least one ballistic protection module 2 and at least one fastening system 10 to a military vehicle.

[0095] First, a decision must be made as to whether the respective ballistic protection element 2 should be attached to the military vehicle via a single or multiple attachment point. In addition to the mass and dimensions of the ballistic protection element 2, the accessibility of potential attachment points also plays a role in this decision. Subsequently, the respective threaded studs 4 are welded to the military vehicle according to the selection.

[0096] In the case of a single connection, a threaded stud 4 is used, which, due to its cross-sectional geometry, can provide anti-rotation protection, for example a threaded stud 4 with a rectangular or trapezoidal base section A 1, as shown in the Figuren 1a and b is shown. The threaded stud 4 for the individual connection is attached to the military vehicle by means of a, preferably single-layer, U-shaped weld, whereby the properties of the weld joint 7, for example with regard to weld guidance and / or welding material, can be adapted to the respective welding task.

[0097] In the case of multiple connections, several, preferably two or more, threaded studs 4 with a circular cross-section can be used. These can be welded to the military vehicle via the base section A 1 with welds surrounding it all around, in particular multi-layer welds, whereby suitable weld parameters are selected analogously to single connections.

[0098] In both cases, the ballistic protection element 2, which has been previously provided with recesses 3 that fit the corresponding threaded studs 4 in terms of their positioning and cross-sectional geometry, is then placed onto the threaded studs 4. The ballistic protection element 2 is supported on the threaded stud 4 via the respective contact surface. In the case of a single connection, there is generally surface contact between the base section A 1 of the threaded stud 4 and the base receiving area B 1 of the recess 3, whereas in the case of multiple connections, the contact surface is typically located in the area of ​​the threaded section A 2 or the thread receiving area B 2. The stepped recess 3 of the ballistic protection element 2 has contact surfaces that serve to ensure correct positioning relative to the threaded stud 4.Furthermore, the weld connection 7 is received by the groove 9 in the case of a single connection and by the threaded receiving area B 2 in the case of a multiple connection.

[0099] The threaded bolt 5 and the fastening element 6 are then mounted. The fastening element 6 is first slipped over the bolt shank 5.3 so that the curved clamping surfaces 5.1 and 6.1 are in contact with each other. The threaded bolt 5 is then screwed into the threaded socket 4, for which a tool that interacts with the drive profile of the bolt head 5.2 can be used. The chamfers 8 on the threaded bolt 5 and the threaded socket 4 facilitate the screwing process. After being screwed in with a certain torque, the fastening element 6 is clamped against the ballistic protection element 2, and the curved clamping surfaces 5.1 and 6.1 are in contact with each other, allowing force to be transmitted.

[0100] The material selection, particularly for the threaded bolt 5 and the fastening element 6, should be such that force dissipation and compensation for movements of the ballistic protective elements 2 are possible through the use of a tough material in the fastening element 6. At the same time, the threaded bolt 5 should exhibit the highest possible strength to reliably withstand the prevailing stresses from ballistic threats.

[0101] The protection system 1 described above and the military vehicle with such a protection system 1 are characterized by a favorable distribution and / or diversion of the forces acting on the protection system 1 during firing and / or splashing via the curved clamping surfaces 5.1, 6.1. Bezugszeichen:

[0102] 1 Protective system 2 Protective element 3 Recess 4 Threaded boss 4.1 Boss bore 5 Threaded bolt 5.1 Clamping surface 5.2 Bolt head 5.3 Bolt shank 6 Fastening element 6.1 Clamping surface 6.2 Cylinder countersink 7 Welded joint 7.1 Weld layer 8 Chamfer 9 Groove 9.1 Groove end 10 Fastening system A1 Base section A2 Thread section E Screw-in axis B1 Base receiving area B2 Thread receiving area R Screw-in direction

Claims

1. Protection system (1) for a military vehicle, comprising at least one ballistic protection element (2) and at least one fastening system (10), which has a threaded boss (4) that can be arranged on the military vehicle and extends at least partially into a recess (3) of the ballistic protection element (2), a threaded bolt (5) screwed into the threaded boss (4) and a fastening element (6) clamped against the ballistic protection element (2) via the threaded bolt (5), characterized by that the threaded bolt (5) and the fastening element (6) abut each other via curved clamping surfaces (5.1, 6.1).

2. Protection system according to claim 1, characterized by the fact that the adjacent clamping surfaces (5.1, 6.1) are formed by spherical surfaces.

3. Protection system according to claim 2, characterized by the fact that the spherical surfaces are designed as annular spherical surfaces arranged on the threaded bolt (5) and the fastening element (6).

4. Protection system according to one of claims 2 or 3, characterized by the fact that the spherical surfaces are integrally arranged on the threaded bolt (5) and / or the fastening element (6).

5. Protection system according to one of the preceding claims, characterized by the fact that the threaded boss (4) has a base section (A1) for attachment to the military vehicle and a threaded section (A2) for screwing in the threaded bolt (5) in the opposite direction of screwing in (R).

6. Protection system according to claim 5, characterized by the fact that the outer diameter of the threaded shank (4) in the base section (A1) is larger than in the threaded section (A2).

7. Protection system according to one of claims 5 or 6, characterized by the fact that the threaded stud (4) can be attached to the military vehicle via a welded connection (7) formed between the base section (A1) and the military vehicle.

8. Protection system according to one of claims 5 to 7, characterized by the fact thatthe base section (A1) of the threaded shank (4) has a square cross-section.

9. Protection system according to one of the preceding claims, characterized by the fact that the fastening element (6) is disc-shaped and / or has a ballistically optimized, in particular trapezoidal, cross-section.

10. Protection system according to claim 9, characterized by the fact that the fastening element (6) is designed and arranged such that it at least partially covers the weld joint (7) transversely to the screwing direction (R) of the threaded bolt (5).

11. Protection system according to one of the preceding claims, characterized by the fact that the material of the fastening element (6) has a greater toughness than the material of the threaded bolt (5).

12. Protection system according to claim 11, characterized by the fact thatthe material of the fastening element (6) has an elongation at break of at least 12%, determined in a tensile test with a specimen length which is five times the specimen diameter and / or that the material of the fastening element (6) has a tensile strength of at least 1,000 N / mm² 2 and / or a 0.2% yield strength of at least 850 N / mm² 2 exhibits.

13. Protection system according to one of claims 11 or 12, characterized by the fact that the material of the threaded bolt (5) has an elongation at break of at least 9%, determined in a tensile test with a specimen length which corresponds to five times the specimen diameter and / or that the material of the threaded bolt (5) has a tensile strength of at least 1,040 N / mm² 2 and / or a 0.2% yield strength of at least 940 N / mm² 2 exhibits.

14. Protection system according to one of claims 11 to 13, characterized by the fact thatthe material of the fastening element (6) has an impact energy of at least 45 joules and / or the material of the threaded bolt (5) has an impact energy of at least 27 joules, determined in the Charpy impact bending test with V-shaped notched specimens.

15. Military vehicle with at least one protection system (10), characterized by the fact that the protection system (10) is designed according to one of the preceding claims.

Images