DE102011116114A1 - Deformation structure for motor car, has deformation elements arranged such that total load level on elements is dispersed, where elements are temporarily decoupled from each other with respect to introduction of force acting upon crash - Google Patents

Abstract

The structure (1) has deformation elements that are deformable with crash on an obstruction under creation of certain deformation loading levels. The deformation elements are arranged and formed such that total load level on the deformation elements is dispersed and the deformation elements are temporarily mechanically decoupled from each other with respect to introduction of force acting upon the crash by a light spacing located between the deformation elements, where the deformation elements have different large force working regions.

Description

The invention relates to a deformation structure of a motor vehicle, comprising a first deformation element and at least one second deformation element, wherein the deformation elements are deformable in an impact on an obstacle to produce certain deformation load levels.

Such a deformation structure is for example in the DE 10 2006 036 902 A1 described.

In this case, the deformation structure has deformation elements which are set up and adapted to switch between different deformation load levels in response to the reaching of at least one threshold value of a control parameter. Specifically, it is possible to switch between a plurality of different stiffnesses of the deformation elements for a deformation.

Control parameters and associated threshold can be, for example, the deformation path of a deformation element and a predetermined length on the deformation path, as a function of which the load level is changed accordingly.

Other control parameters mentioned may be the pressure threshold value of a liquid in a chamber of a deformation element or else external parameters which are supplied by a vehicle sensor system.

Overall, this should make it possible to differentiate the impact reaction of a vehicle depending on the impact type and speed or to increase the adaptability of the deformation structure to different load cases.

However, the deformation structures described in the cited document are constructed comparatively complex. Sometimes pyrotechnic elements are used to enable existing load paths in the deformation structures to change the load level.

The present invention is based on the object to provide a deformation structure of the type mentioned, which is relatively simple and also has an increased adaptability to possible different load cases.

This object is achieved by the features of claim 1. Advantageous embodiments or developments of the invention are the respective claims withdrawn.

The invention is based on a deformation structure of a motor vehicle, comprising a first deformation element and at least one second deformation element, wherein the deformation elements are deformable in the event of an impact on an obstacle while generating certain deformation load levels.

According to the invention, at least two deformation elements are arranged and configured relative to one another in such a way that the total load level can be distributed to the at least two deformation elements in an impact and the deformation elements mechanically decoupled from each other at least temporarily with regard to the introduction of a load acting on them in the event of an impact are.

In this way, an increased adaptability of the deformation structure with respect to different load cases can be achieved.

Thus, it is particularly possible that upon impact of the deformation structure on a soft obstacle only a portion of the deformation elements is deformed due to the force introduced into this with a comparatively low deformation load level, while another part of the deformation elements for each introduced into this Force is already too stiff and not deformed.

The deformation of only a portion of the deformation elements, even at a low deformation load level, can nevertheless already be used to generate signals and detected by suitable sensors, in particular structure-borne sound sensors, and further by means of appropriate evaluation and control devices (possibly together with other sensor signals) can be processed. For example, depending on the detected signals existing systems of vehicle safety from the motor vehicle can be activated early.

If, however, the impact of the deformation structure on a hard obstacle, so there is a deformation of all deformation elements, since the stiffness of the individual deformation elements themselves no longer withstand the forces distributed to these and the deformation elements to produce a "total deformation load levels" reduce the impact energy together ,

In this case, a mechanical decoupling of the at least two deformation elements in a very simple manner by at least one clearance between them is possible.

Thus, a load caused by an impact can be easily separated into partial loads, which are then introduced into the deformation elements. A deformation of the deformation elements can be independent of each other.

It is very possible to distribute the total load level as desired to the deformation elements and thus make necessary adjustments to specific vehicle types, especially if the at least two deformation elements have different sized force-attack surfaces.

Although it is quite conceivable to provide the deformation structure according to the invention in any impact areas of a motor vehicle, for example in the side area or in the rear area, it has proved particularly expedient that the deformation elements are part of a front structure of the motor vehicle and connected to a side member via at least one connecting element wherein at least one of the deformation elements is connected to a bumper cross member and at least one other of the deformation elements of the bumper cross member is mechanically decoupled. This leads in particular to an increased adaptability of the motor vehicle to different load cases in the region of its front structure.

It can be provided in particular that the at least two deformation elements are tube-shaped or sleeve-like, wherein a deformation element surrounds the other with a circumferential, clearance and the outer deformation element is connected to the bumper cross member and the internal deformation element is positioned such that In the case of a deformation, only the outer deformation element can pass through an opening in the bumper cross member.

So it is possible in a structurally simple manner, even at relatively low load levels, which are generated, for example. In a collision on a soft obstacle, a deformation to reduce impact energy without deformation of the deformation elements downstream structure elements, such as of the longitudinal member takes place.

In this case, the impact-side force application surfaces of the deformation elements are preferably located in a force introduction plane, so that in a collision, the force is applied to this approximately at the same time. In this way, upon impact with a heavy obstacle, the entire deformation load level of the deformation structure can be made available from the beginning to reduce the impact energy.

Alternatively, it is also conceivable that the at least two deformation elements are tube-shaped or sleeve-like, wherein a deformation element surrounds the other with a circumferential, clear distance and the outer deformation element is connected to the bumper cross member and the internal deformation element at a distance from the bumper Crossbar is positioned such that it at least temporarily receives no load in the event of deformation of only the outer deformation element. In this case (assuming the exceeding of a certain impact force), the outer deformation element will first deform and, after a certain time offset (in the millisecond range) or after a certain deformation path, also the inner deformation element, wherein the deformation load levels of the deformation elements will jump to a total deformation Add load level.

According to a further alternative it can also be provided that the at least two deformation elements are arranged side by side (ie not surrounded), the deformation elements are separated by a clearance and one of the deformation elements is connected to the bumper cross member and the other deformation element such is positioned so that it can pass in the case of deformation of only connected to the bumper cross member deformation element on the bumper cross member over.

Here too, the impact surfaces facing the force application surfaces of the deformation elements are preferably approximately at a force introduction level. It can be achieved a similar high adaptability of the deformation structure to different load cases as in the other described alternatives.

However, the invention also relates to a motor vehicle with at least one deformation structure according to the invention. If the deformation structure is part of a front structure of the motor vehicle, it is preferable to provide at least two deformation structures according to the invention for the left and right sides.

The increased adaptability to different load cases due to the deformation structures according to the invention has an advantageous effect on the crash severity detection by means of downstream sensor systems. Detecting soft and hard crashes is made easier.

In summary, the at least two deformation elements of the deformation structure according to the invention are thus arranged and designed so that in an impact below a certain level of force, the deformation of only a smaller number, in particular only one of the deformation occurs and in an impact above this level of force additionally the deformation of at least one further, in particular of the second deformation element takes place, such that the deformation load levels generated of the deformed deformation elements add at least temporarily.

Preferred embodiments of the invention are illustrated in the drawings and will be explained in more detail in the following description. The same reference numerals refer to the same, comparable or functionally identical components.

It show, each schematically

1 a motor vehicle from above with dashed lines, according to the invention deformation structures,

2 a view according to II 1 , where only the deformation structures are shown,

3 a longitudinal section according to section line III 2 .

4 a deformation structure according to the invention comparable to a view according to 3 in a second embodiment,

5 a view, also comparable to the 3 in a further embodiment and

6 a perspective view of a deformation structure according to the invention according to a fourth embodiment.

First, on the 1 to 3 Referenced.

In the figures, a motor vehicle K can be seen, which in its front structure two deformation structures according to the invention 1 having. As part of the front structure are only longitudinal beams 6 and a bumper cross member mechanically connected thereto 4 indicated by dashed lines.

Every deformation structure 1 essentially comprises a first tubular or sleeve-like deformation element 2 and this one with a clear distance 8th surrounding second, tubular or sleeve-like deformation element 3 , In particular, the deformation elements 2 . 3 formed rotationally symmetrical in cross section. However, other than rotationally symmetric deformation elements are conceivable.

The deformation elements 2 and 3 are each on a so-called bulkhead 5 attached and over this with a side member 6 connected.

The second, external deformation element 3 is impact side with the bumper cross member 4 connected.

It can also be seen that the bumper cross member 4 a roughly circular opening 7 which is at a clear distance 9 approximately concentric to the first deformation element 2 is aligned.

Optionally, in the clearance 9 annular spacers, for example. Made of plastic, be provided (not shown).

In the illustrated embodiment are (effective) force introduction surfaces A1 and A2 of the deformation elements 3 and 2 approximately at a common force introduction level 10 ,

Furthermore, dashed lines is a bumper 11 indicated in the space further means for increasing the pedestrian protection can be provided (not shown in detail).

If the motor vehicle K now impinges on an impact obstacle H, this is due to the deformation structure according to the invention 1 an overall impact force F caused by the impact on the first deformation element 2 (F2) and on the second deformation element 3 (F1) distributed.

By the mechanical coupling of the second deformation element 3 with the bumper cross member 4 and the effective thereby large force introduction surface A1, the second deformation element 3 take a comparatively large force F1, while the on the first deformation element 2 introduced force F2, due to the much smaller force introduction area A2, is significantly lower.

If the total impact force F, for example, due to the impact on a soft obstacle, falls below a certain value, then only the second, outer deformation element will become 3 deformed.

By the between the deformation elements 2 and 3 located clear distance 8th and between the first deformation element 2 and the opening 7 located clear distance 9 are the deformation elements 2 and 3 with regard to the Initially, the load F acting on it in an impact substantially mechanically decoupled from each other. The second deformation element 3 can thus be independent of the first deformation element 2 deform.

In 4 is a similar deformation structure 1' shown.

In contrast to the deformation structure 1 , indicates the deformation structure 1' a bumper cross member 4 ' which is not with one of the opening 7 provided comparable opening.

Accordingly, there is also an altered internal deformation element 2 ' provided, which compared to the deformation element 3 something is shortened, so that is between the bumper cross member 4 ' and an impact side end face of the deformation element 2 ' a clear distance 12 formed.

Also in this embodiment takes place through the clearances 8th respectively. 12 in terms of initiation of an impact on the deformation structure 1' acting load at least temporarily mechanical decoupling of the deformation elements 2 ' and 3 ,

This is the case when the deformation structure hits 1' on the impact obstacle H, the resulting total impact force F only after overcoming the clearance by the clearance 12 predetermined deformation path on the deformation elements 2 ' (F2) and 3 (F1) and thus, if necessary, increases the deformation load level by leaps and bounds.

5 shows a further deformation structure according to the invention 1'' in which, in contrast to the preceding embodiments, the deformation elements are not arranged in each other, but next to each other.

This is a rod-like deformation element 3 again with a bumper cross member 4 ' connected and another rod-like deformation element 2 '' at a clear distance 8th below the deformation element 3 arranged.

As a result, in a collision in turn can easily the total load level F on the deformation elements 3 (F1) and 2 '' (F2) are distributed.

By the coupling of the deformation element 3 to the bumper cross member 4 ' has the deformation element 3 again a much larger force-attack surface than the deformation element 2 '' on.

In a soft impact, therefore, only the upper deformation element 3 deform, with the underlying deformation element 2 '' can be seen positioned so that it is below the bumper cross member 4 ' unhindered to get past this.

In 6 Finally, a fourth embodiment of a deformation structure according to the invention will be briefly described.

This is a deformation structure 1''' which, unlike those in the 1 to 4 apparent deformation structures tubular or sleeve-like deformation elements 2 ''' and 3 ' has, which are rectangular in cross-section.

Otherwise, everything has a comparable structure. So both are deformation elements 2 ''' and 3 ' on a bulkhead plate 5 attached and over this with a side member 6 connected. The deformation element 3 ' encloses the internal deformation element 2 ''' one-sided with a clearance 8th , wherein the deformation element 3 ''' with a bumper cross member 4 '' connected, for example, is welded.

In addition, the bumper cross member 4 '' with a rectangular, in particular square opening 7 ' provided, in which the inner deformation element 2 ''' in the case of a sole deformation of the deformation element 3 ' while maintaining an all-round, clear distance 9 can get in or out.

Although only two deformation elements are shown per deformation structure in the illustrated embodiments, it is quite conceivable to provide even more deformation elements with a correspondingly possible distribution of a total impact force, without departing from the inventive idea of the present invention.

LIST OF REFERENCE NUMBERS

1, 1 ', 1' ', 1' ''

deformation structure

2, 2 ', 2' ', 2' ''

first deformation element

3, 3 '

second deformation element

4, 4 ', 4' '

Bumper crossmember

5

Schott plate

6

longitudinal beams

7, 7 '

Opening in the bumper cross member

8th

clear distance between the deformation elements

9

clear distance between the first deformation element and the opening

10

Force introduction level of the bumper cross member

11

Bumpers incl. Means for pedestrian protection

12

clear distance of the first deformation element from the bumper cross member

A1, A2

effective force transmission surfaces

F

Total impact force

F1

Impact force distributed on the first deformation element

F2

Impact force distributed to the second deformation element

H

Crash barrier

K

motor vehicle

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 102006036902 A1 [0002]

Claims (8)

Deformation structure ( 1 ) of a motor vehicle (K), comprising a first deformation element ( 2 .) And at least one second deformation element ( 3 ), wherein the deformation elements ( 2 . 3 ) are deformable in the event of an impact on an obstacle (H) while generating certain deformation load levels (F1, F2), characterized in that the at least two deformation elements ( 2 . 3 ) are arranged and configured in such a way that, in the event of an impact, the total load level (F) on the at least two deformation elements ( 2 . 3 ) and the deformation elements ( 2 . 3 ) with regard to the initiation of an impact on 2 . 3 ) acting load (F1, F2) are at least temporarily mechanically decoupled from each other. Deformation structure ( 1 . 1' . 1'' . 1''' ) according to claim 1, characterized in that the at least two deformation elements ( 2 . 2 ' . 2 '' . 2 ''' . 3 . 3 ' ) by at least one clearance between them ( 8th . 9 . 12 ) are mechanically decoupled from each other. Deformation structure ( 1 ) according to claim 1 or 2, characterized in that the at least two deformation elements ( 2 . 3 ) have different sized force-attack surfaces (A1, A2). Deformation structure ( 1 . 1' . 1'' . 1''' ) according to one of claims 1 to 3, characterized in that the deformation elements ( 2 . 2 ' . 2 '' . 2 ''' . 3 . 3 ' ) Are part of a front structure of the motor vehicle (K) and via at least one connecting element ( 5 ) with a side member ( 6 ), at least one ( 3 . 3 ' ) of the deformation elements ( 2 . 2 ' . 2 '' . 2 ''' . 3 . 3 ' ) with a bumper cross member ( 4 . 4 ' . 4 '' ) and at least one other ( 2 . 2 ' . 2 '' . 2 ''' ) of the deformation elements ( 2 . 2 ' . 2 '' . 2 ''' . 3 . 3 ' ) of the bumper cross member ( 4 . 4 ' . 4 '' ) is mechanically decoupled. Deformation structure ( 1 . 1''' ) according to claim 4, characterized in that the at least two deformation elements ( 2 . 2 ''' . 3 . 3 ' ) are constructed tube-like or sleeve-like, wherein a deformation element ( 3 . 3 ' ) the other ( 2 . 2 ''' ) with a circumferential, clear distance ( 8th ) and the outer deformation element ( 3 . 3 ' ) with the bumper cross member ( 4 . 4 '' ) and the internal deformation element ( 2 . 2 ''' ) is positioned in such a way that, in the event of deformation, only the outer deformation element ( 3 . 3 ' ) through an opening ( 7 . 7 ' ) of the bumper cross member ( 4 . 4 '' ) can get. Deformation structure ( 1' ) according to claim 4, characterized in that the at least two deformation elements ( 2 ' . 3 ) are constructed tube-like or sleeve-like, wherein a deformation element ( 3 ) the other ( 2 ' ) with a circumferential, clear distance ( 8th ) and the outer deformation element ( 3 ) with the bumper cross member ( 4 ' ) and the internal deformation element ( 2 ' ) at a distance ( 12 ) to the bumper cross member ( 4 ' ) is positioned such that in the event of deformation of only the outer deformation element ( 3 ) at least temporarily no load. Deformation structure ( 1'' ) according to claim 4, characterized in that the at least two deformation elements ( 2 '' . 3 ) are arranged side by side, wherein the deformation elements ( 2 '' . 3 ) by a clearance ( 8th ) are separated from each other and one of the deformation elements ( 3 ) with the bumper cross member ( 4 ' ) and the other deformation element ( 2 '' ) is positioned so that in case of deformation only the one with the bumper cross member ( 4 ' ) associated deformation element ( 3 ) on the bumper cross member ( 4 ' ) can get over. Motor vehicle (K) with at least one deformation structure ( 1 . 1' . 1'' . 1''' ) according to one of claims 1 to 7.

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