Cost-effective crossbeam arrangement for a crash management system

Abstract

Crossbeam arrangement (14) for a crash management system of a motor vehicle, with a crossbeam (16) to absorb impact forces introduced in the X direction, wherein the crossbeam (16) has hollow chambers (26) open in the Z direction, and at least one impact cup (18) projecting in the X direction from the cross member (16) and supported on a longitudinal member (12) for absorbing at least part of the impact forces by plastic deformation, wherein the impact pot (18) has gaps (30) formed between deformable folding walls (28) and open in the Z direction for receiving the plastically deformed folding walls (28), wherein the impact pot (18) is formed integrally with the cross member (16), wherein the cross member (16) has a rear side (20) pointing in the X direction for limiting the hollow chambers (26), wherein the rear side (20) of the cross member (16) is open in the area of ​​at least one impact pot (18), wherein the folding walls (28) of the impact pot (18) are attached to at least one side surface of a hollow chamber wall (24) positioned within the crossbeam (16) and / or the folding walls (28) of the impact pot (18) are attached to at least one end face of a hollow chamber wall (24) positioned within the crossbeam (16) in extension of the hollow chamber wall (24). characterized by the fact that the folding walls (28) of the impact pot (18) are composed of partial walls designed as a flat plate and connected at an acute angle to form a fir tree profile.

Description

[0001] The invention relates to a crossbeam arrangement for a crash management system, which can be used to dissipate impact forces in a crash in a cost-effective manner.

[0002] From DE 10 2004 008 741 A1 an extruded crossbeam with hollow chambers open in the Z direction is known, in which an opening for inserting a crash box is provided on the inside facing a longitudinal beam, wherein the crash box can also be integrally formed with the crossbeam and can have a multi-chamber profile.

[0003] From DE 10 2008 029 634 A1 a bumper for a motor vehicle is known with a cross member having hollow chambers extending in the Y direction, wherein a central hollow chamber is designed to be open over its entire length towards the center of the vehicle, so that a hollow chamber extending and projecting in the X direction of an impact pot can be inserted into the open hollow chamber in order to weld the impact pot to the cross member both outside and inside the hollow chamber of the cross member.

[0004] From DE 10 2004 008 740 A1 a crossbeam arrangement with the features of the preamble of claim 1 is known.

[0005] There is a constant need to be able to dissipate impact forces introduced during a crash through cost-effective measures.

[0006] The purpose of the invention is to demonstrate measures that enable cost-effective dissipation of impact forces.

[0007] The problem is solved according to the invention by a crossbeam arrangement with the features of claim 1. Preferred embodiments of the invention are specified in the dependent claims and the following description, each of which, individually or in combination, can represent an aspect of the invention. When a feature is presented in combination with another feature, this serves only to simplify the presentation of the invention and is in no way intended to imply that this feature cannot also be a further development of the invention without the other feature.

[0008] One embodiment relates to a crossbeam arrangement for a crash management system of a motor vehicle, comprising a crossbeam for absorbing impact forces introduced in the X-direction, wherein the crossbeam has hollow chambers open in the Z-direction, and at least one impact pot projecting in the X-direction from the crossbeam and supported on a longitudinal member for absorbing at least a part of the impact forces by plastic deformation, wherein the impact pot has spaces formed between deformable folding walls and open in the Z-direction for receiving the plastically deformed folding walls, wherein the impact pot is formed integrally with the crossbeam, wherein the crossbeam has a rear side facing in the X-direction for limiting the hollow chambers, wherein the rear side of the crossbeam is open in the area of ​​at least one impact pot.wherein the folding walls of the impact cup are attached to at least one side surface of a hollow chamber wall positioned within the crossbeam and / or the folding walls of the impact cup are attached to at least one end face of a hollow chamber wall positioned within the crossbeam in extension of the hollow chamber wall.

[0009] Since at least one impact cup is formed integrally with the crossbeam, a separate fastening system is unnecessary. This reduces the number of components and the assembly effort. Because both the hollow chambers of the crossbeam and the spaces within the impact cup are open in the Z-direction, a three-dimensional shape is achieved that allows for virtually arbitrarily complex geometries in the X- and Y-directions. This is particularly useful for utilizing the hollow chambers of the crossbeam for additional functions and / or ensuring a defined folding of the impact cup during the dissipation of impact forces by the deformation energy required for the plastic deformation of the folding walls. Simultaneously, the entire crossbeam assembly can be manufactured cost-effectively and, in particular, almost without tooling, using tools aligned in the designated Z-direction of the crossbeam assembly.This reduces manufacturing costs. The one-piece design of the impact cup with the crossbeam and the hollow chambers and spacers open in the Z-direction allows the entire crossbeam assembly to be manufactured cost-effectively by primary forming, thus enabling cost-effective dissipation of impact forces.

[0010] The X-direction refers to a coordinate direction along a longitudinal axis of a motor vehicle when the crossmember assembly is installed in the vehicle. The X-direction is essentially horizontal when the vehicle is parked on a level, horizontal surface. The Y-direction refers to a coordinate direction along a transverse axis of a motor vehicle when the crossmember assembly is installed in the vehicle. The Y-direction is essentially horizontal when the vehicle is parked on a level, horizontal surface. The Z-direction refers to a coordinate direction along a vertical axis of a motor vehicle when the crossmember assembly is installed in the vehicle. The Z-direction is essentially vertical when the vehicle is parked on a level, horizontal surface.The X-direction, the Y-direction, and the Z-direction are orthogonally aligned with each other.

[0011] A crash management system (CMS) of a motor vehicle is understood to be an environment within a vehicle designed to keep impact forces generated in an accident ("crash") as far away from the passenger compartment as possible, in order to prevent injury to the vehicle occupants. To achieve this, the crash management system may incorporate stiffening components that absorb and support the impact forces. However, it is also possible for the crash management system to dissipate the impact forces through controlled plastic deformation in response to the impact forces. This plastic deformation is ideally implemented in areas of the vehicle where it is unlikely to endanger the vehicle occupants.

[0012] The hollow chambers of the crossmember enable a material-saving lightweight construction, allowing high forces to be supported cost-effectively with minimal material usage. In particular, the hollow chambers are bounded by hollow chamber walls, which are preferably designed as flat plates. The side surfaces of the hollow chamber walls extend exclusively in the Z-direction. The crossmember can have a rear surface facing partially towards the vehicle center and a front surface facing partially away from the vehicle center in the X-direction, between which the hollow chambers are formed. The rear surface and / or the front surface have a substantially smooth, stepless surface, which is preferably slightly curved to better integrate into the vehicle's outer skin.

[0013] The folding walls of the impact cup are composed of flat plates joined at an acute angle to form a fir-tree profile. Preferably, several folding walls are arranged one behind the other in the Y-direction, spaced apart from each other. When impact forces are absorbed in the X-direction, the folding walls can fold together and deform plastically to dissipate the impact forces. This plastic deformation of the folding walls can reduce the X-direction of the impact cup.

[0014] In particular, the crossbeam and the one-piece impact cup are produced by extrusion along their designated Z-direction. A material intended for extruding the one-piece crossbeam assembly can be extruded through a die, resulting in the Z-direction-opening hollow chambers of the crossbeam and the Z-direction-opening spaces of the impact cup. The respective crossbeam assembly can be cut to a desired length in the Z-direction, which corresponds to the extrusion direction. The crossbeam assembly can be made of a plastic material. This allows the manufacturing costs for the crossbeam assembly to be kept particularly low.

[0015] Preferably, the impact cup has an end plate extending in the X-direction to cover an end of the longitudinal beam extending in the X-direction and at least one mounting projection extending from the end plate in the X-direction for attachment to the longitudinal beam by means of a fastener oriented in the Y-direction. The impact cup can thus, for example, have a U-shaped end contour facing the longitudinal beam. This allows the impact cup to, for example, grip the longitudinal beam in a U-shape, thereby enabling the end plate to be positioned in the X-direction and the at least one mounting projection, preferably two spaced-apart mounting projections, to be centered in the Y-direction relative to the longitudinal beam. Furthermore, the at least one mounting projection allows for easy attachment to the longitudinal beam, with the fastener being easily accessible during installation due to its Y-direction orientation. This simplifies the installation process.Furthermore, the end plate and the mounting attachment can also be easily produced as single-piece parts of the crossbeam assembly by extrusion with an extrusion direction corresponding to the designated Z-direction. This keeps manufacturing costs low.

[0016] Particularly preferably, the crossbeam has a rear face extending in the X-direction to define the hollow chambers, with the folding walls of at least one impact cup being attached to the rear face of the crossbeam. This allows the shaping of the folding walls of the impact cup and the shaping of the hollow chambers of the crossbeam to be independent of each other. This simplifies the functionalization of the hollow chambers of the crossbeam for additional uses, for example, as part of a media-carrying conduit, without having to compromise the shape design of the folding walls for the impact cup.

[0017] If, according to the invention, the folding walls of the impact cup are attached to at least one side surface of a hollow chamber wall positioned within the crossbeam, the functional length of the impact cup in the X-direction can be extended into the interior of the crossbeam, thereby providing further design freedom in the configuration of the folding mechanism of the impact cup during the dissipation of impact forces. In particular, if the hollow chamber into which the at least one folding wall of the impact cup projects is not functionalized for other purposes, this hollow chamber can contribute to at least supporting the dissipation of impact forces.

[0018] If, according to the invention, the folding walls of the impact cup are attached to at least one end face of a hollow chamber wall positioned within the crossbeam, extending from the hollow chamber wall, a portion of the folding wall of the impact cup can continue into the associated hollow chamber wall. This also makes it possible to support the hollow chamber walls within the crossbeam for the dissipation of impact forces through a defined deformation. The impact cup can thus be integrated into the crossbeam to such an extent that a sharp functional demarcation between the impact cup and the crossbeam is hardly possible anymore. Parts of the crossbeam can also take over functions that were originally performed by the impact cup.

[0019] Preferably, at least one hollow chamber of the crossmember is connected to a fluid line, particularly for the exhaust air of a charge air cooler. At least one hollow chamber, preferably several adjacent hollow chambers, can limit the flow cross-section of a fluid-carrying line. This allows the fluid to be guided through the crossmember in the Z-direction in a very space-saving manner and, in particular, to be discharged at a suitable point or supplied to another vehicle component, for example, a radiator and / or an air conditioning system.

[0020] Another embodiment relates to a support frame for a motor vehicle crash management system, comprising a first longitudinal member oriented in the X-direction, a second longitudinal member oriented in the X-direction, and a cross member arrangement which can be designed and further developed as described above, wherein the cross member arrangement is connected to the first longitudinal member and to the second longitudinal member via an impact cup in each case. Due to the one-piece design of the impact cup with the cross member and the hollow chambers and spacers open in the Z-direction, the entire cross member arrangement can be manufactured cost-effectively by primary forming, thus enabling cost-effective dissipation of impact forces in the support frame.

[0021] In particular, the first longitudinal beam and / or the second longitudinal beam has a mounting opening, especially a slot-shaped one, open in the X-direction for inserting a mounting bracket for the impact absorber, with a fastening element oriented in the Y-direction connecting the mounting bracket to the associated longitudinal beam. The mounting brackets inserted into the respective associated longitudinal beams also allow for easy pre-setting of the relative position of the impact absorber and the entire crossbeam assembly in the Z-direction. Preferably, each mounting bracket has an opening that corresponds to an opening in the longitudinal beam, so that the fastening element can, for example, act as a locking bolt and securely connect the crossbeam assembly to the respective longitudinal beam.

[0022] The invention is explained below by way of example with reference to the accompanying drawings and preferred embodiments, wherein the features shown below can represent an aspect of the invention, either individually or in combination. The drawings show: Fig. 1 a schematic top view of a left half of a first embodiment of a support frame, Fig. 2 a schematic top view of a right half of a second embodiment of a support frame and Fig. 3 a schematic top view of a detail of a right half of a third embodiment of a support frame.

[0023] The in Fig. The partially depicted support frame 10 can be used for a motor vehicle's crash management system. The support frame 10 typically has two or more longitudinal members 12, which can be connected at the front and / or rear to a cross member assembly 14. The cross member assembly 14 includes a cross member 16, which can, in particular, be part of a bumper of the motor vehicle. The cross member 16 is supported at its end against the respective longitudinal member 12 by means of an impact absorber 18. In the event of a crash in the direction of travel of the motor vehicle, i.e., in the X-direction, the impact absorber 18 between the cross member 16 and the longitudinal member 12 can be compressed by plastic deformation, thereby dissipating the impact forces and protecting vehicle occupants from injury.

[0024] The crossbeam 16 has a rear face 20 facing the longitudinal beam 12 and a front face 22 facing away from the longitudinal beam 12, between which hollow chambers 26 are formed, bounded by hollow chamber walls 24. The hollow chambers 26 are open in the vertical direction, i.e., in the Z-direction. The crossbeam 16 does not have a top or bottom surface to close the hollow chambers 26. At least one hollow chamber 26 can therefore be configured as part of a fluid-carrying line.

[0025] The impact cup 18 has, in particular, zigzag-shaped folding walls 28 that can be plastically deformed and folded under load. The folding walls 28, which are roughly aligned in the X-direction, are spaced apart from one another by gaps 30. These gaps 30 provide a volume into which the plastically folded walls 28 can expand. The gaps 30 are open in the vertical direction, i.e., in the Z-direction. The impact cup 18 does not have a top or bottom surface to close the gaps 30. Furthermore, the impact cup 18 has an end plate 32 facing the longitudinal beam 12, from which mounting lugs 34 project in the X-direction.The mounting elements 34 can be connected to the longitudinal member 12 via fastening means 38 extending in the transverse direction of the motor vehicle, i.e. in the Y direction, whereby the cross member arrangement 14 can be connected to the longitudinal member 12 in a defined relative position and integrated into the support frame 10.

[0026] The impact cup 18 is formed in one piece with the crossbeam 16. Since both the hollow chambers 26 of the crossbeam 16 and the spaces 30 of the impact cup 18 are open in the Z-direction and the mounting projections 34 extending in the X-direction only extend in the Z-direction, it is possible to manufacture the entire crossbeam assembly 14 by extrusion or compression molding through a suitably shaped die, the extrusion direction corresponding to the designated Z-direction of the crossbeam 16.

[0027] At the in Fig. In the embodiment of the crossbeam arrangement 14 shown in Figure 1, the impact pot 18 with its folding walls 28 is attached directly to the rear 20 of the crossbeam 16.

[0028] As in Fig. As shown in Figure 2, the impact cup 18 with its folding walls 28 can project partially into the interior of the crossbeam 16 through an opening formed in the rear side 20. At least part of the folding walls 28 can traverse a hollow chamber 26 and, particularly in the center, extend to a side surface of the associated hollow chamber wall 24.

[0029] As in Fig. As shown in Figure 3, at least one folding wall 28 of the impact cup 18, which partially projects into the interior of the crossbeam 16, can transition into a hollow chamber wall 24, so that the hollow chamber wall 24 adjoining the folding wall 28 at its end face can form part of the folding wall 28.

Claims

[1] Cross member arrangement (14) for a crash management system of a motor vehicle, with a cross member (16) for absorbing impact forces introduced in the X-direction, wherein the cross member (16) has hollow chambers (26) open in the Z direction, and at least one impact absorber (18) projecting in the X-direction from the cross member (16) and supportable on a longitudinal member (12) for absorbing at least part of the impact forces by plastic deformation, wherein the impact pot (18) has intermediate spaces (30) formed between deformable folding walls (28) and open in the Z direction for receiving the plastically deformed folding walls (28), wherein the impact pot (18) is formed in one piece with the cross member (16), wherein the cross member (16) has a rear side (20) pointing in the X-direction for delimiting the hollow chambers (26), wherein the rear side (20) of the cross member (16) is open in the region of at least one impact pot (18), wherein the folding walls (28) of the impact pot (18) are attached to at least one side surface of a hollow chamber wall (24) positioned within the cross member (16) and / or the folding walls (28) of the impact pot (18) are attached to at least one end face of a hollow chamber wall (24) positioned within the cross member (16) in an extension of the hollow chamber wall (24) characterized by , that the folding walls (28) of the impact pot (18) are composed of partial walls designed as a flat plate which are connected to one another at an acute angle to form a fir tree profile. [2] Cross member arrangement (14) according to claim 1 characterized by that the cross member (16) and the one-piece impact pot (18) are produced by extrusion along their designated Z-direction. [3] Cross member arrangement (14) according to claim 1 or 2 characterized by that the impact pot (18) has an end plate (32) pointing in the X direction for covering an end of the longitudinal member (12) pointing in the X direction and at least one mounting projection (34) projecting in the X direction from the end plate (32) for fastening to the longitudinal member (12) by means of a fastening means (36) oriented in the Y direction. [4] Cross member arrangement (14) according to one of claims 1 to 3 characterized by that the cross member (16) has a rear side (20) pointing in the X direction for delimiting the hollow chambers (26), wherein the folding walls (28) of at least one impact pot (18) are attached to the rear side (20) of the cross member (16). [5] Cross member arrangement (14) according to one of claims 1 to 4 characterized bythat part of the folding walls (28) passes through the hollow chamber (26). [6] Cross member arrangement (14) according to one of claims 1 to 5 characterized by that several folding walls (28) are provided one behind the other in the Y direction, each spaced apart from one another by an intermediate space. [7] Cross member arrangement (14) according to one of claims 1 to 6 characterized by that at least one hollow chamber (26) of the cross member (16) is connected to a fluid line, in particular for exhaust air from a charge air cooler. [8] Supporting frame (10) for a crash management system of a motor vehicle, with a first longitudinal member (12) aligned in the X direction, a second longitudinal member (12) aligned in the X direction and a cross member arrangement (14) according to one of claims 1 to 7, wherein the cross member arrangement (14) is connected to the first longitudinal member (12) and to the second longitudinal member (12) via a respective impact pot (18). [9] Support frame (10) according to claim 8 characterized by in that the first longitudinal member (12) and / or the second longitudinal member (12) has a mounting opening open in the X direction, in particular a slot-shaped one, for inserting a mounting attachment (34) of the impact drop (18), wherein a fastening means (36) aligned in the Y direction connects the mounting attachment (34) to the associated longitudinal member (12).

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