Method for manufacturing a protective element for the armoring of a motor vehicle, as well as a protective element manufactured by the method and a motor vehicle with at least one such protective element

Abstract

Method for manufacturing a protective element (1) for armoring a motor vehicle, formed from several flat or curved individual profiles (2, 3, 4), in which at least two directly adjacent individual profiles (2, 3, 4) are arranged at an angle other than 180° to each other, characterized by the following method steps: a) Providing the individual profiles (2, 3, 4), b) Welding the individual profiles (2, 3, 4) together to form a basic shape of the protective element (1) by creating weld seams (5, 6), c) Inserting the basic shape of the protective element (1) into a forming tool, d) Final forming of the basic shape of the protective element (1) to the protective element (1).

Description

[0001] The invention relates to a method for manufacturing a protective element for the armoring of a motor vehicle according to the preamble of claim 1. Furthermore, the invention relates to a protective element manufactured according to this method according to claim 10 and to a motor vehicle with at least one such protective element according to claim 11.

[0002] Such protective elements for the armoring of motor vehicles are used in military vehicles as well as civilian armored vehicles to protect against ballistic and detonation impacts. These protective elements for motor vehicles are often manufactured from molded parts formed from flat sheets or plates. However, the forming process of these molded parts results in bending radii that can negatively impact the protective function of the vehicle. Bending reduces the protective surface area because projectiles are deflected at the bending radii and can unintentionally penetrate the vehicle interior. Furthermore, the smaller the bending radius, i.e., the larger the bend itself, the thinner the material becomes at the bending point of the workpiece.However, even with large bending radii, i.e., with slight bending, the workpiece's strength decreases. Therefore, the use of such molded parts for protective elements in motor vehicles is insufficient to ensure the protective function of the element, particularly in the bending area.

[0003] Alternatively, such protective elements can be manufactured from flat or curved blanks or individual profiles made of already hardened protective steel. These blanks or individual profiles are then welded together. However, due to the high hardness of such protective steels, the shaping possibilities are limited. Furthermore, a loss of hardness, and thus a reduction in the protective effect of the manufactured element, occurs in the weld seam or in the heat-affected zone between the individual blanks or profiles.

[0004] German patent DE 10 2010 001 117 A1 discloses a vehicle floor consisting of several individual sheets of armor steel welded together. These individual sheets are welded together. After welding, the sheets are tempered, and then the final vehicle floor is produced by forming. However, this method also suffers from the previously described problem of weakening the protective element in the area of ​​the bending radii resulting from the forming process.

[0005] Furthermore, DE 10 2015 105 865 A1 discloses a method for forming a vehicle body structure in which an insert blank and a base blank are arranged together in a surface-to-surface orientation to create an butt joint between the insert blank and the base blank, each being composed of an aluminum alloy; the insert blank is spot-welded to the base blank by forming a series of resistance weld points on the butt joint of the two blanks to form a pre-welded blank assembly; and the pre-welded blank assembly is deformed such that a section of the base blank and an adjacent overlapping section of the insert blank are deformed simultaneously.Although some of the process steps of the invention are applied in this method, this method is not suitable for manufacturing protective elements for the armoring of a motor vehicle.

[0006] DE 10 2008 012 720 A1 discloses armor plating for a vehicle, which is formed from two separate and at least partially identically configured plates of armor steel. The two plates are placed one behind the other in a congruent arrangement and then welded together.

[0007] DE 10 2005 014 298 A1 discloses a method for armoring a vehicle with a component made of hardened steel, whereby the process enables the production of high-strength armor elements with the highest precision. Due to the shape adapted to the vehicle's internal contours, it is possible to reduce weight and simultaneously significantly reduce the number of welds.

[0008] Further state of the art is known from DE 10 2011 053 698 C5, DE 10 2010 009 183 A1, DE 10 2011 055 687 A1, DE 10 2012 106 950 A1 and DE10 2008 044 693 B4.

[0009] It is therefore an object of the invention to provide a method for manufacturing a protective element for the armoring of a motor vehicle, wherein the protective element maintains the necessary protective effect over its entire extent without experiencing any weakening or reduction in protective capacity in specific areas during manufacturing. In particular, no bending radii that impair the protective effect of the protective element should occur. Furthermore, it is also an object of the invention to provide such a protective element and a motor vehicle with at least one protective element.

[0010] The problem is solved methodically by a method for manufacturing a protective element for armoring a motor vehicle with all the features of claim 1. With regard to the protective element and the motor vehicle, the problem is solved by a protective element with all the features of claim 10 and by a motor vehicle with all the features of claim 11. Advantageous embodiments of the invention are found in the dependent claims.

[0011] The inventive method for manufacturing a protective element for armoring a motor vehicle, formed from several flat or curved individual profiles, in which at least two directly adjacent individual profiles are arranged at an angle other than 180° to each other, is characterized by the following process steps: a) Providing the individual profiles, b) Welding the individual profiles together to form a basic shape of the protective element by creating weld seams, c) Placing the basic shape of the protective element into a forming tool, d) Final forming of the basic shape of the protective element to the protective element.

[0012] A particularly advantageous feature of the inventive method for manufacturing a motor vehicle armor plating from several flat or curved individual profiles is that, in the final forming step, no bending is required to align the original individual profiles at the desired angle (other than 180°) relative to each other. In this basic form of the protective element to be manufactured, the individual profiles are already aligned at the desired angle (other than 180°) relative to each other and welded together. Thus, no bending radii are created in the area of ​​the welds during final forming, which would weaken the protective element and consequently its protective effect.Particularly in the area of ​​the welds between the individual profiles of the protective element, where the actual final forming takes place, especially sharp edges can be produced without the bending radii that arise during bending processes for arranging the individual profiles at an angle other than 180°. Such sharp edges offer a significantly higher level of protection for the protective elements according to the invention than conventional bending radii of known protective elements, since the area of ​​the bend in the weld region, and thus the probability of a projectile being deflected in the area of ​​the sharp edges, is significantly reduced.

[0013] The inventive method advantageously combines the benefits of tool tempering, particularly the complex shaping and homogeneous hardness distribution within the component, with the advantages of welded solutions, especially the sharp-edged design of structures. Even though this involves an additional manufacturing step, the advantages achieved through the synergistic effect outweigh the disadvantages with regard to the protective effect of the protective elements produced using the inventive method.

[0014] In the inventive method, the final forming of the basic shape of the protective element into the protective element can be carried out essentially without conventional bending. This avoids the small bending radii that occur in conventional bending, which would weaken the protective element and thus its protective effect, even though the protective element may still be subjected to bending processes in the forming tool. However, these bending processes no longer produce sharp edges, i.e., no small bending radii. Therefore, the advantages known from tool tempering, namely complex shaping and homogeneous hardness distribution throughout the entire protective element, are achieved while simultaneously forming the sharp-edged structures in the area of ​​the weld seams of two directly adjacent individual profiles of the protective element arranged at an angle other than 180° to each other.

[0015] In a particular embodiment of the invention, the basic shape of the protective element is reshaped only in the area of ​​the welds and, if applicable, in areas directly adjacent to the welds, forming sharp edges. Other areas of the basic shape are not reshaped during the final forming process.

[0016] According to the invention, it has proven particularly advantageous that the final forming of the basic shape of the protective element into the protective element is achieved essentially only by bending in the area of ​​the welds between two directly adjacent individual profiles arranged at an angle other than 180° to each other, or in the boundary regions of these individual profiles and the welds. This makes it possible to form the basic shape essentially only in the area of ​​these welds, thus avoiding any weakening of the material in this area. In particular, this significantly increases the protective effect in the area of ​​the welds compared to protective elements known from the prior art, without any significant weakening of the material in the area of ​​the welds.

[0017] According to a further aspect of the invention, it is provided that the individual profiles are supplied as individual profiles made of steels, in particular roll-hardened steels, especially preferably roll-hardened protective steels.

[0018] It is possible that the individual profiles are provided as individual profiles manufactured from a flat sheet of metal.

[0019] It is also possible that the individual profiles are provided as individual profiles made from already hardened steel, in particular hardened protective steel.

[0020] With all these possibilities for the starting materials of the individual profiles, it is ensured that the individual profiles are provided with protective properties sufficient for the protective effect and thus already have the required protective properties for use as a protective element in a motor vehicle, in particular in an armored military vehicle as well as in an armored civilian protection vehicle, without any further processing.

[0021] However, according to a further aspect of the invention, it is also possible to heat the basic shape of the protective element to austenitizing temperature before final forming. This causes a structural change within the steels or metals used for the individual profiles or the protective element, which can also be used for armor plating, such as magnesium alloys, aluminum alloys, and titanium alloys. In particular, a face-centered cubic modification of the crystal structure occurs.

[0022] This makes it possible, according to a further advantageous aspect of the inventive method, to temper the basic shape of the protective element after heating it to austenitizing temperature, with this tempering preferably taking place in the forming tool after or during the final forming. The tempering represents a combined heat treatment consisting of hardening and subsequent tempering.

[0023] While this type of tempering generally refers to the material steel, it is also common with non-ferrous metals such as magnesium, aluminum, and titanium alloys, resulting in thermal microstructure formation and modification. For hardening, the basic shape of the protective element must first be heated above the austenitizing temperature. This is followed by quenching, i.e., the rapid cooling of the now fully formed protective element. The resulting microstructure is influenced by the quenching rate and can be adjusted accordingly by a skilled person. An immediate tempering step after quenching is advantageous. In this step, the brittle tetragonal martensite formed during the hardening of the steel is transformed into the cubic martensite microstructure through the precipitation of fine carbides.This material has a smaller volume and relaxes the crystal's grain structure, eliminating the so-called glassy hardness of the material. Therefore, this process step allows for the production of particularly effective protective elements with correspondingly good protective properties for motor vehicles.

[0024] According to a further particularly advantageous aspect of the invention, it has proven useful to employ a wide variety of welding processes for welding the individual profiles. These include, in particular, laser welding, plasma welding, or gas metal arc welding with filler wire, wherein the filler wire has an essentially analogous alloy composition to that of the individual profiles.

[0025] When using laser or plasma welding, this is generally done as butt welding. In this case, the resulting weld seam essentially has the same alloy composition as the individual profiles themselves. However, even when using gas metal arc welding with filler wire, where this filler wire has an essentially similar alloy composition to the individual profiles, a substantially homogeneous weld seam is produced, whose composition essentially corresponds to the alloy composition of the individual profiles. In particular, it is important to ensure that any filler materials used in the welding processes, such as electrodes or wires in the protective element being manufactured, are ferritic so that a microstructural transformation can occur.

[0026] The tempering process following the welding creates a virtually homogeneous transition between the individual profiles, so that the entire protective element has a substantially homogeneous alloy composition, even in the weld seams. During final forming, the weld seams are then shaped into the appropriately sharp edges without the need for bending processes that would negatively impact the protective function of the element.

[0027] Furthermore, it has proven particularly effective to manufacture a protective element such as an A-, B- or C-pillar, a front wall, a sill, a hatch, a wheel arch, a vehicle floor or the like.

[0028] According to the invention, a protective element for a motor vehicle, manufactured according to a previously described method according to the invention, is also to be independently protected. A motor vehicle with at least one such protective element is also to have independent protection according to the invention.

[0029] Further objectives, advantages, features, and applications of the present invention will become apparent from the following description of an exemplary embodiment with reference to the drawings. All features described and / or illustrated, individually or in any meaningful combination, constitute the subject matter of the present invention, even independently of their compilation in the claims or their cross-references.

[0030] They show: Fig. 1: An embodiment of a protective element according to the invention in the form of a B-pillar in a top view and Fig. 2: a sectional view of the B-pillar of the Fig. 1 along the cutting plane AA.

[0031] In the Fig. Figure 1 shows an embodiment of a protective element 1 according to the invention in the form of a B-pillar in a top view. The protective element 1 consists of three correspondingly pre-formed original individual profiles 2, 3 and 4. The individual profiles 2, 3 and 4 are already cut and bent before the protective element 1 is manufactured in such a way that they can be joined together to form a basic shape of the protective element 1 without the need for further forming of the individual profiles 2, 3 and 4.

[0032] To ensure the basic shape of the protective element 1 is dimensionally stable, the individual profiles 2 and 3 are joined together by a weld 6, and the individual profiles 2 and 4 are joined together by a weld 5. Suitable welding processes include laser welding, plasma welding, or gas metal arc welding with filler wire, whereby the filler wire in gas metal arc welding has an essentially analogous alloy composition to that of the individual profiles 2, 3, and 4.

[0033] In the present case of the protective element 1 designed as a B-pillar, the individual profiles 2, 3, and 4 are made of a suitable steel. After the three individual profiles 2, 3, and 4 have been welded together to form the basic shape of the protective element 1, which already has the finished shape of the B-pillar, the basic shape of the protective element 1 is then placed in a forming tool designed as a press and formed into the finished protective element as a B-pillar by heat treatment followed by final forming. During the forming of the basic shape of the protective element 1 in the forming tool designed as a press, the sharp edges 7 and 8 are created in the area of ​​the welds 5 and 6 between the individual profiles 2 and 4 and 2 and 3, respectively.This forming process in the press essentially corresponds to bending only in the area of ​​the welds 5 and 6 and the adjacent areas of the individual profiles 2, 3 and 4, forming the sharp edges 7 and 8.

[0034] As in particular the sectional view of the Fig. 2 along the cutting plane AA of the Fig.As can be seen from Figure 1, the individual profiles 2 and 3, as well as the individual profiles 2 and 4, are arranged at approximately a right angle of 90° to each other. The manufacturing process allows protective elements 1 to be produced without bending and thus without material-weakening bending radii. These elements form sharp edges 7 and 8 in the connection area of ​​the welds 5 and 6. These sharp edges 7 and 8 are significantly better suited for use in such protective elements 1 than bending radii resulting from bending processes known from the prior art, and thus offer considerably more effective protection against ballistic impacts and detonations. Reference symbol list 1 protective element 2 single profiles 3 individual profiles 4 individual profiles 5 weld seam 6 weld seam 7-edge 8 edge AA section plane

Claims

[1] Method for manufacturing a protective element (1) for armoring a motor vehicle, formed from several flat or curved individual profiles (2, 3, 4), in which at least two directly adjacent individual profiles (2, 3, 4) are arranged at an angle other than 180° to each other, characterized by the following procedural steps: a) Providing the individual profiles (2, 3, 4), b) Welding the individual profiles (2, 3, 4) together to form a basic shape of the protective element (1) by creating weld seams (5, 6), c) Inserting the basic shape of the protective element (1) into a forming tool, d) Final forming of the basic shape of the protective element (1) to the protective element (1). [2] Method according to claim 1, characterized by , that the individual profiles (2, 3, 4) are provided as individual profiles (2, 3, 4) made from steels, in particular roll-hardened steels, especially preferably from roll-hardened protective steels. [3] Method according to claim 1 or 2, characterized by , that the individual profiles (2, 3, 4) are provided as individual profiles (2, 3, 4) produced from a flat sheet metal blank. [4] Method according to claim 1 or 2, characterized by , that the individual profiles (2, 3, 4) are provided as individual profiles (2, 3, 4) made from already hardened steel, in particular hardened protective steel. [5] Method according to any one of the preceding claims, characterized by , that during the final forming process, the basic shape of the protective element (1) is transformed only in the area of ​​the welds (5, 6) and, if applicable, in areas directly adjacent to the welds (5, 6), forming sharp edges (7, 8). [6] Method according to any one of the preceding claims, characterized by , that the basic shape of the protective element (1) is heated to austenitizing temperature before final forming. [7] Method according to claim 5, characterized by, that the basic shape of the protective element (1) is tempered after heating to austenitizing temperature, wherein this tempering preferably takes place in the forming tool after or during the final forming. [8] Method according to any one of the preceding claims, characterized by , that as a protective element (1) an A-, B- or C-pillar, a front wall, a sill, a hatch, a wheel arch, a vehicle floor or the like is manufactured. [9] Method according to any one of the preceding claims, characterized by , that during the final forming of the basic shape of the protective element (1) to the protective element (1) the weld seams (5, 6) are formed less than the directly adjacent areas of the individual profiles (2, 3, 4). [10] Protective element (1) for armoring a motor vehicle made from several flat or curved individual profiles (2, 3, 4), wherein at least two directly adjacent individual profiles (2, 3, 4) are arranged at an angle other than 180° to each other, the manufacture comprising the following process steps: a) Providing the individual profiles (2, 3, 4), b) Welding the individual profiles (2, 3, 4) together to form a basic shape of the protective element (1) by creating weld seams (5, 6), c) Inserting the basic shape of the protective element (1) into a forming tool, d) Final forming of the basic shape of the protective element (1) to the protective element (1). [11] Motor vehicle with at least one protective element (1) for armoring a motor vehicle made from several flat or curved individual profiles (2, 3, 4), wherein at least two directly adjacent individual profiles (2, 3, 4) are arranged at an angle other than 180° to each other, the manufacture comprising the following process steps: a) Providing the individual profiles (2, 3, 4), b) Welding the individual profiles (2, 3, 4) together to form a basic shape of the protective element (1) by creating weld seams (5, 6), c) Inserting the basic shape of the protective element (1) into a forming tool, d) Final forming of the basic shape of the protective element (1) to the protective element (1).

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