Crash box for motor vehicle

Abstract

The invention relates to a crash box (2) for a motor vehicle (1) having a vehicle longitudinal beam extending in the vehicle longitudinal direction (X) and a cross beam (3) extending in the vehicle width direction, the rear end (21) of which can be fastened to the side of the vehicle longitudinal beam facing away from the passenger compartment of the motor vehicle, the front end (22) of the crash box can be fastened to the side of the cross member facing the passenger compartment of the motor vehicle, and wherein the crash box has a cable (5) which extends in the longitudinal direction of the vehicle from the front end to the rear end of the crash box and is connected to the front and rear ends of the crash box in each case.

Description

Technical Field

[0001] The invention relates to a crash box for a motor vehicle and a motor vehicle having the crash box. Background Art

[0002] EP 1 742 818 B1 describes a crash box of this type for a motor vehicle, which has at least one crash box component that can be deformed in the event of a collision and absorbs energy by deforming in the event of a collision. The crash box includes at least one weakening tool that weakens the overall structure of the at least one crash box component in order to adjust the energy absorption capacity of the crash box component, thereby reducing the rigidity of the crash box component.

[0003] As described in DE 10 2011 083 372 A1, it is generally known in motor vehicle construction to fix a crash box to the front end of the engine longitudinal beam. A front bumper is mounted at the front end of the crash box. In order to fix the crash box to such a vehicle longitudinal beam, it is known to weld an end plate at the end end of the vehicle longitudinal beam, which end plate protrudes from the vehicle longitudinal beam in a flange-like manner in the vehicle height direction and the vehicle transverse direction. The crash box can be screwed to this end plate.

[0004] Bumper systems must meet a wide range of scenario requirements (e.g. speed, obstacles, impact locations, etc.). The so-called small overlap test results in locally high loads in the front structure of the motor vehicle. In order to introduce forces over a larger area under such load conditions, strips are conventionally installed along the cross member, i.e. strips extending along the cross member in the transverse direction of the vehicle. This mounting position has proven to be ineffective. The reasons for this are that the strips have large length tolerances and that they are difficult to fix in this mounting position under load, i.e. they may slip under load. Summary of the invention

[0005] Against the background of the above-mentioned prior art, the object of the present invention is to provide a device which is suitable for enriching the prior art.

[0006] This object is achieved by the features of the independent claim. The dependent claims contain preferred developments of the invention.

[0007] The object is therefore achieved by a crash box for a motor vehicle, the motor vehicle comprising a vehicle longitudinal beam extending in the longitudinal direction of the vehicle and a cross beam extending in the width direction of the vehicle, the rear end of the crash box being fixable on a side of the vehicle longitudinal beam facing away from a passenger compartment of the motor vehicle, and the front end of the crash box being fixable on a side of the cross beam facing the passenger compartment of the motor vehicle.

[0008] The crash box has a cable which extends in the longitudinal direction of the vehicle from a front end to a rear end of the crash box, is connected to the rear end of the crash box and can be connected to the cross member.

[0009] In other words, a crash box or deformation box (Defobox for short) of this type for a motor vehicle is provided. The motor vehicle can be a passenger car (especially a car) and / or a commercial vehicle (especially a truck). The motor vehicle can have a so-called crash management system in the front structure of the vehicle, which has a crossbeam, one or more crash boxes and, if necessary, other mounting parts. For so-called low-speed collisions, the crash management system has sufficient flexibility, because compared to conventional crash boxes, the crash box proposed by the present invention is not reinforced due to the cable being arranged as a component that only absorbs tensile forces. However, high strength can be achieved under the load conditions of so-called high-speed collisions, because the disconnection of the crash box from the crossbeam can be avoided due to the connection of the crash box to the crossbeam via the cable. Therefore, these two requirements, which are actually in conflict with each other, can be achieved by the solution proposed by the present invention, because by simply installing additional screws for directly screwing the crash box on the crossbeam, it is possible to avoid strengthening the connection structure between the crossbeam and the deformation box, which may endanger the realization of the load conditions of low-speed collisions. Furthermore, the connection or fastening by means of cables proposed by the invention can prevent the cross member from becoming disconnected from the crash box in a so-called small overlap collision, which usually occurs locally on the side of the motor vehicle facing away from the load. This makes it possible to prevent possible damage to the fuel line installed at this location due to disconnection.

[0010] The following is a detailed description of possible improvements to the above-mentioned collision box.

[0011] The cable can be arranged (optionally completely) inside the crash box. In other words, the crash box can have a housing, by which the crash box can be fastened (optionally screwed) to the longitudinal beam and the cross beam. The cable can be arranged in the housing, wherein the cable can extend in the longitudinal direction of the vehicle from a front end to a rear end of the housing of the crash box and the cable can be connected to the rear end of the housing of the crash box.

[0012] Integration of the cable into the crash box enables reliable positioning and guidance of the cable during a crash. Furthermore, integration into the crash box does not require any additional installation space. This allows a space-saving or compact solution to be provided, so that the remaining small free space in the engine compartment of the front structure of the motor vehicle is not further restricted. Furthermore, since the crash box can be provided and assembled as a single component, this allows a relatively simple assembly of the component crash box.

[0013] The cable can be connected to the rear end of the crash box via at least one spring element.

[0014] The spring element is designed as a spring clip which is arranged at the rear end of the crash box.

[0015] The spring element can generate a preload of the cable, the value or magnitude of which can be adjusted or determined by selecting the spring constant. This makes it possible to compensate for component tolerances of the strip and avoid negative effects of cable slack.

[0016] The spring element can be arranged (optionally completely) inside the crash box. This further enhances the effects described above with regard to the integration of the cable into the crash box.

[0017] In other words, in addition to or as an alternative to the cable, a spring element, which is optionally designed as a spring clip, may be arranged in the above-mentioned housing of the crash box, wherein the spring element may be fastened to the rear end of the housing of the crash box.

[0018] The cable may be connectable to the cross member via a connecting element held at the front end of the crash box.

[0019] The connecting element can (optionally completely) be arranged inside the crash box.

[0020] In other words, in addition to or instead of the cable and / or the spring element, a connecting element can be arranged in the above-mentioned housing of the crash box, wherein the connecting element can be fixed at the front end of the housing of the crash box or can be held there. This further enhances the effects described above with regard to the integration of the cable into the crash box.

[0021] The connecting element can have an internal thread, so that the crash box can be fastened to the cross member by means of a screw connection.

[0022] The crash box can be designed to be deformed in the longitudinal direction of the vehicle by folding when a force of a predetermined magnitude acts on the crash box from the front in the longitudinal direction of the vehicle.

[0023] The cables may be steel cables and / or plastic cables, optionally polyester cables.

[0024] In addition, a motor vehicle is provided, which has the above-mentioned crash box, a vehicle longitudinal beam extending in the longitudinal direction of the vehicle, and a cross beam extending in the width direction of the vehicle, wherein the rear end of the crash box is fixed to the side of the vehicle longitudinal beam facing away from the passenger compartment of the motor vehicle, and the front end of the crash box is fixed to the side of the cross beam facing the passenger compartment of the motor vehicle. The crash box has a cable extending from the front end to the rear end of the crash box in the longitudinal direction of the vehicle, and the cable is connected to the rear end of the crash box and can be connected to the cross beam.

[0025] What has been described above with respect to the crash box also applies analogously to the motor vehicle, and vice versa. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Refer to below Figures 1 to 4 An implementation manner is described.

[0027] Figure 1 The interior or the inner structure of a crash box for a motor vehicle, which is mounted on a cross member, is shown schematically and in perspective.

[0028] Figure 2 Schematically shown in a top view Figure 1 The collision box in

[0029] Figure 3 Schematically shown in top view Figure 1 and Figure 2 A collision box in the embodiment of the present invention is mounted on the crossbeam,

[0030] Figure 4 Schematically and perspectively shown Figures 1 to 3 The rear end of the crash box in the first assembly state or the initial assembly state,

[0031] Figure 5 Schematically and perspectively shown Figures 1 to 4 The rear end of the crash box in the second assembled state, and

[0032] Figure 6 Schematically and perspectively shown Figures 1 to 5 The rear end of the crash box in the third or final assembly state. DETAILED DESCRIPTION

[0033] exist Figures 1 to 6 In the description, the same reference numerals are used for the same objects, and the following description refers to all Figures 1 to 6 conduct.

[0034] In all Figures 1 to 6 , respectively, a Cartesian coordinate system is shown. The coordinate system comprises an X-axis extending in the longitudinal direction X of the vehicle, a Y-axis extending in the width direction Y of the vehicle, and a Z-axis extending in the height direction Z of the vehicle. The X-axis here extends from the front to the rear of the motor vehicle 1 , i.e., opposite to the main driving direction of the motor vehicle 1 .

[0035] If especially by Figure 1 As can be seen, crash box 2 of motor vehicle 1 (not shown in further detail) can be connected to a vehicle longitudinal beam (not shown) extending in vehicle longitudinal direction X, to which rear end 21 can be fastened via two screws on the side of the vehicle longitudinal beam facing away from the passenger compartment of motor vehicle 1 .

[0036] If especially by Figure 1 As shown in FIG. 1 , the crash box 2 is connected to the cross member 3 extending in the vehicle width direction Y, and the front end portion 22 of the crash box 2 is also connected via two screws 4 (in Figure 1 The cross member (only one of which is shown or visible) is fastened to a side of the cross member that faces the passenger compartment of the motor vehicle 1 .

[0037] The crash box 2 has a cable 5 which is arranged completely inside the crash box 2 and extends from a front end 22 to a rear end 21 of the crash box 2 in the vehicle longitudinal direction X. In the present case, the cable 5 is designed as a plastic cable; a steel cable is also conceivable.

[0038] Despite the cables 5 , the crash box 2 is designed like a conventional crash box in order to deform by folding in the vehicle longitudinal direction X when subjected to a force of a predetermined magnitude acting on the crash box 2 from the front via the cross member in the vehicle longitudinal direction X.

[0039] If especially by Figure 2 and Figure 3 As can be seen, the cable 5 is connected to the rear end 21 of the crash box 2 and is held at the front end 22 of the crash box 2 via a stop 23 and a connecting element 7 connected to the cable 5 and also arranged inside the crash box 2. Furthermore, the cable 5 is connected to the cross member 3 at the front end 22 of the crash box 2 via a screw 6 or is fixed thereto, for which purpose the connecting element 7 has an internal thread into which the screw 6 engages.

[0040] In this case, the cable 5 is connected to the rear end 21 of the crash box 2 via at least one spring element 8 and is thus prestressed in the crash box 2 , wherein the spring element 8 (eg, in particular, a spring element 8) is Figure 6 81. By means of the spring clip 81, length tolerances in the longitudinal direction X of the vehicle can be compensated and tolerances (so-called joint gaps) when the crash box 2 is mounted on the cross member 3 can be ensured, as in particular due to Figure 3 As visible.

[0041] During the assembly of the crash box 2, first, the rear connecting element 9 connected to the rear end of the cable 5 is guided through the through hole 10 at the rear end 21 of the crash box 2 (see Figure 4 ). Subsequently, the clamp 82 is inserted laterally in order to hold the connecting element 9 and thus the cable 5 at the rear end 21 of the crash box 2 (see Figure 5 Then, in a final step, the spring clip 81 is also pushed laterally between the clamp 82 and the connecting element 9, thereby generating a preload (see Figure 6 ).

[0042] In summary, it is therefore proposed to integrate so-called small overlap strips (see above) into the crash box (in the longitudinal direction of the vehicle) in order to transfer the large tensile forces in the system in a high-speed collision and thus prevent the cross member from breaking off from the crash box. However, the small overlap strip does not transfer compressive forces and therefore has no influence on the behavior in a low-speed collision due to the described installation position.

[0043] Therefore, it is proposed to integrate the restriction band (Fangband) in an optimized structural space to meet the small overlap requirement in collision. Reference numerals list

[0044] 1Motor Vehicle

[0045] 2 collision boxes

[0046] 21 Rear end of the crash box

[0047] 22 Front end of the collision box

[0048] 23 A stopper for holding the cable at the front end of the crash box

[0049] 3 beams

[0050] 4 screws for connecting the crash box to the crossbeam

[0051] 5 Cable

[0052] 6 screws for fixing the cables to the crossbeam

[0053] 7Front connecting element for fixing the cable to the crossbeam

[0054] 8 Spring element

[0055] 81 elastic clip

[0056] 82 Clamp

[0057] 9 Rear connecting element for fixing the cable at the rear end of the crash box

[0058] 10Through hole at the rear end of the crash box

[0059] X vehicle longitudinal direction

[0060] Y vehicle width direction

[0061] Z vehicle height direction

Claims

1. A crash box (2) for a motor vehicle (1), the motor vehicle having a vehicle longitudinal beam extending in a vehicle longitudinal direction (X) and a cross beam (3) extending in a vehicle width direction (Y), the rear end (21) of the crash box (2) being fixable on a side of the vehicle longitudinal beam facing away from a passenger compartment of the motor vehicle (1), and the front end (22) of the crash box (2) being fixable on a side of the cross beam facing toward a passenger compartment of the motor vehicle (1), wherein: - the crash box (2) has a cable (5) extending from a front end to a rear end (21, 22) of the crash box (2) along the longitudinal direction (X) of the vehicle, the cable being connected to the rear end (21) of the crash box (2) and being connectable to the cross member (3), It is characterized in that The cable (5) is connected to the rear end (21) of the crash box (2) via at least one spring element (8).

2. The crash box (2) according to claim 1, characterized in that: The cable (5) is arranged inside the crash box (2).

3. The crash box (2) according to claim 1 or 2, characterized in that: The spring element is embodied as a spring clip (8) which is arranged at a rear end (21) of the crash box (2).

4. The crash box (2) according to any one of claims 1 to 3, characterized in that: The cable can be connected to the crossbeam (3) via a connecting element (7) held at a front end (22) of the crash box (2).

5. The crash box (2) according to claim 4, characterized in that: The connecting element (7) is arranged inside the crash box (2).

6. The crash box (2) according to claim 4 or 5, characterized in that The connecting element (7) has an internal thread, so that the crash box (2) can be fixed on the crossbeam (3) by means of a threaded connection.

7. The crash box (2) according to any one of claims 1 to 6, characterized in that The crash box (2) is designed to be deformed by folding in the longitudinal direction (X) of the vehicle when a force of a predetermined magnitude acts on the crash box (2) from the front in the longitudinal direction (X) of the vehicle.

8. The crash box (2) according to any one of claims 1 to 7, characterized in that: The cable (5) is a steel cable and / or a plastic cable.

9. A motor vehicle (1), comprising a crash box (2) according to any one of claims 1 to 9, a vehicle longitudinal beam extending in the longitudinal direction (X) of the vehicle, and a cross beam (3) extending in the width direction (Y) of the vehicle, wherein the rear end (21) of the crash box (2) is fixed to a side of the vehicle longitudinal beam facing away from a passenger compartment of the motor vehicle (1), and the front end (22) of the crash box (2) is fixed to a side of the cross beam facing toward the passenger compartment of the motor vehicle (1), - the crash box (2) has a cable (5) extending from a front end to a rear end (21, 22) of the crash box (2) along the longitudinal direction (X) of the vehicle, the cable being connected to the rear end (21) of the crash box (2) and being connectable to the cross member (3), It is characterized in that The cable (5) is connected to the rear end (21) of the crash box (2) via at least one spring element (8).

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