DE102011121397A1 - Bumper for motor vehicle e.g. passenger car, has deformable barrier element having wall portions with outside edges that are vertically movable during transition from non-deformed state to deformed state - Google Patents

Abstract

The bumper has a deformable barrier element (20) that is contacted with an outer surface of the bumper main structure. An outer side of the bumper main structure is inclined towards an inner side diagonally. The wall portions (23,24) of deformable barrier element are transitioned from non-deformed state to deformed state during collision. The outside edges (33,34) of wall portions are vertically movable during transition from non-deformed state to deformed state. An independent claim is included for a motor vehicle.

Description

The invention relates to a bumper for a motor vehicle, in particular a passenger car, with an element deformable in contact with an obstacle impinging on an outside of the bumper. the.

A bumper whose deformable element comprises a first wall section which slopes or descends obliquely from the outside to an inside of the bumper and swivels into a steeper orientation during the transition from the undeformed state to the inside of the bumper is known from US Pat U.S. Patent 6,513,843 B1 known. The bumper described there comprises a cross member, which is preceded by a deformable by the impingement of an obstacle foam core. In addition, an obliquely outwardly sloping wall is attached to the cross member, which carries at its lower edge a panel. When the bumper touches a pedestrian and becomes deformed, the sloping wall deviates downward so that the trim originally at ankle height drops to foot level. By the bumper grasps the pedestrian's lower leg over its entire length, it can be ensured that it is not pulled under the vehicle and instead the pedestrian tilts on the front hood. However, since the panel must first abut the lower leg of the pedestrian before it dodges down in contact with this, there is a risk that this evasive movement itself leads to injury.

The object of the invention is to provide a bumper for a motor vehicle or a motor vehicle, which minimize the risk of injury when in contact with a pedestrian.

The object is achieved on the one hand, in a bumper for a motor vehicle, in particular for a passenger car, with a first in contact with an impinging on an outer side of the bumper obstacle deformable element, the one from the outside to an inner side of the bumper obliquely - or descending, in the transition from undeformierten in the deformed state in a steeper orientation pivoting first wall portion comprises, a side facing away from the outside edge of the first wall portion through the transition from undeformierten in the deformed vertically movable. Since in the conventional bumper described above, this opposite edge attached to the cross member and therefore vertically immovable, the wall portion can only give in to the impact of an obstacle by its outer edge escapes down. By according to the invention, the inside edge of the wall portion is vertically movable, a vertical movement of the outside edge can be minimized and preferably completely avoided.

Preferably, the first deformable element comprises a second wall portion which tapers towards the outside on the first wall portion. By pivoting these two wall sections in a steeper position in contact with an obstacle, the surface on which the obstacle is supported, can be widened upwards and downwards, so that the forces occurring spread over a large area and the burden of the obstacle is minimized.

Third and fourth wall portions of the deformable member converging toward each other from the outside allow the vertical movement of the edges facing away from the outside of the first and second wall portions by pivoting in a collision opposite to the first and second wall portions.

If the third and fourth wall sections are wider than the first and second wall sections and edges of the third and fourth wall sections facing away from the outside are immovable relative to one another, an intermediate stage results during the deformation of the deformable element, in which the first and second wall sections substantially lie in one plane and form a triangle with the third and fourth wall sections. Thereby, the deformation resistance of the deformable member can be increased in the course of its deformation, and the risk of the obstacle breaking through to non-deformable parts of the vehicle can be reduced.

A non-deformable part may, in particular, be a first carrier on which a region of the deformable element remote from the outside, in particular the edges of the third and fourth wall sections facing away from the outside, can be fastened.

The deformable element can be designed simply and inexpensively as a hollow profile. In particular, the hollow profile is preferably formed from a flat material blank, wherein two edges of the flat material blank are then expediently fastened to the first carrier. The hollow profile may in particular have a diamond-shaped or □-shaped cross section, wherein preferably the two outer legs of the □ are fastened to the first carrier.

The first deformable element may expediently be arranged behind an outer skin of the bumper.

A second deformable element may be provided over the first deformable element to distribute the forces occurring in a collision over a large area. The second deformable element may extend in front of a second carrier.

In order to minimize the stress on the knee joints of a pedestrian in contact with a motor vehicle, it has proven to be expedient if the second deformable element is more difficult to deform than the first deformable element.

The second deformable element can essentially be formed by a hard foam body.

The object is further achieved by a motor vehicle, in particular a passenger car with a bumper of the type described above.

To gently grasp the legs of a pedestrian, an edge of the first edge portion of the bumper facing the outside should preferably extend at or just below the knee height of an adult pedestrian.

The second deformable element, if present, is preferably located above knee height.

The invention is explained in the following description with reference to an embodiment shown in simplified form in the accompanying drawing.

Show it:

1 in a simplified schematic sectional view of a front vehicle bumper with a serving as a pedestrian protection deformable element in a non-collision situation with a leg impactor;

2 the bumper and the pedestrian protection element in a first state of deformation after a collision with the leg impactor,

3 the bumper and the pedestrian protection element in a second state of deformation,

4 the deformable element in a simplified spatial representation of the front and

5 the deformable element in sectional view from the side in undeformed and deformed state.

According to 1 are in simplified schematic sectional view of the side of a front 10 a passenger car, not shown, and a previously arranged leg impactor 30 shown. An only partially indicated cooler 11 of the front building 10 is a likewise only partially indicated bumper 12 upstream, at least on its front side and adjoining lateral sections with an example made of plastic injection molded outer skin 13 disguised, which is indicated by outlines. In the outer skin 13 slit-like openings are introduced in the present case, as air passage openings 14 for the wind to the radiator 11 serve.

At a distance behind the outer skin 13 owns the bumper 12 two, for his stiffening and for receiving deformation energy serving, superimposed cross member 15 . 17 , of which the higher arranged, second cross member 15 at its front with a hard foam part 16 is provided, on which an upper segment 19 the outer skin 13 is applied.

At a distance below the second cross member 15 owns the bumper 12 , as already indicated above, a first cross member 17 who at his front 18 a deformable element 20 carries, in the present case as a sheet metal bent part with a cavity 21 is trained. This in 4 shown in perspective view deformable element 20 extends in the present case, at least substantially over the width of the first cross member 17 ,

The bumper system described herein is to be understood as an example of an application of an energy absorber resulting from a collision with the leg impactor 30 deformed so that an impactor touching area of the bumper widened vertically during the deformation, so that the forces occurring spread over a large area and the risk of injury is minimized.

Of course, other cross member constellations and heights above the road are also suitable for application of the described principle.

The deformable element 20 has a support point 22 , in the present case at a lower segment 32 the outer skin 13 in the manner of a line touch 13 is applied and formed by the apex of a rhomboid-like in the present embodiment in cross-section profile. To the the support point 22 forming vertexes of the cross-sectionally similar profile executed close as in 5 shown in perspective view, in the undeformed state of the element 20 in about the same length first and second wall sections 23 and 24 on, with different lengths third and fourth wall sections 25 and 26 over edges 33 . 34 are connected and with these a blunt intermediate angle 27 lock in. The through the first wall section 23 and the shorter third wall section 25 formed upper shorter legs of the element 20 is in the present case at the front with the carrier 17 connected while the longer lower leg of the element 20 passing through the second wall section 24 and the longer fourth wall section 26 is formed, on the underside of the first cross member 17 , For example, by a welded joint, is attached.

2 shows the front building 10 and the leg impactor 30 at the beginning of a collision. All segments 19 . 31 . 32 the outer skin 13 are in contact with the impactor 30 pushed back, with the resistance of the middle, unsupported segment 31 is low compared to the segments 19 . 32 , The hard foam part 16 and the element 20 are visibly compressed, with the wall sections 23 . 24 are pivoted in a nearly vertical orientation. The segment 32 is therefore no longer only linear along the wall sections 23 . 24 connecting crest 22 supported, but lies completely on the wall sections 23 . 24 on. The impactor 30 touches the wall sections 23 . 24 even beyond the edges of the segment 32 In addition, at its entire height, so that the impact forces are distributed over a large area distributed between the bumper and impactor.

The wall sections 25 . 26 extend in this phase is still substantially straight between their upward or downward evaded front edges and their attachment points on the first cross member 17 so that the item 20 a cross-sectional shape similar to a triangle or a parallelogram with the impactor facing long baseline and the first cross member 17 anchored apex assumes.

Another deformation of the element 20 is now only possible if the third and fourth wall sections 25 . 26 begin to bend, especially on the wall section 26 in 3 to recognize. Thus, even at a relatively high collision speed, a puncture of the impactor on the here essentially as not deformable assumed, yielding only in a collision with a heavier obstacle such as an oncoming vehicle cross member 17 be avoided.

5 illustrates the deformation process of the element 20 on the basis of a synopsis. The undeformed cross section of the element 20 is drawn as a dotted line, a strongly deformed state as a solid line. In this strongly deformed state, the wall sections extend 23 . 24 in a plane, ie the vertex 22 is expanded to 180 ° and substantially while maintaining its height against the carrier 17 retreated. The edges 33 . 34 are dodged up or down, leaving the item 20 in the vertical reaches an extent that, if the element 20 she would have in undeformed condition, would impede the cooling air flow to the engine. Because the rear wall sections 25 . 26 Visible are longer than the front, is after widening the vertex 22 at 180 ° another compression of the element 20 only possible if the wall sections 25 . 26 to bend in oneself. Such a bend has on the wall section 26 used visibly.

It is understood that the deformable element, esp. If this is rhombic in the cross-section similar or parallellogrammähnlich or Ω-like formed by simple changes in its dimensions for different bumper assemblies, such as. B. in small cars, middle-class cars, upscale mid-range cars or even in off-road vehicles application, can be optimized.

LIST OF REFERENCE NUMBERS

10

front end

11

cooler

12

bumper

13

shell

14

Air passage opening

15

crossbeam

16

Hard foam part

17

crossbeam

18

front

19

segment

20

deformable element

21

cavity

22

support point

23

first wall section

24

first wall section

25

second wall section

26

second wall section

27

intermediate angle

28

first distance

29

second distance

30

Leg impactor

31

segment

32

segment

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

• US 6513843 B1 [0002]

Claims (15)

Bumpers for a motor vehicle, in particular a passenger car, with a first element deformable in contact with an obstacle striking an outside of the bumper ( 20 ), the one from the outside to an inside of the bumper obliquely on or descending, the first deformed in the deformed state in the transition from the undeformed to the first orientation pivoting ( 23 . 24 ), characterized in that a side facing away from the outside edge ( 33 . 34 ) of the first wall section ( 23 . 24 ) is vertically movable by the transition from the undeformed to the deformed state. Bumper according to claim 1, characterized in that an edge facing the outside ( 22 ) of the first wall section ( 23 . 24 ) maintains its height at the transition to the deformed state. Bumper according to claim 1 or 2, characterized in that the first ( 23 ) and a second wall section ( 24 ) of the first deformable element ( 20 ) run towards each other towards the outside. Bumper according to one of the preceding claims, characterized in that the first deformable element ( 20 ) Further, third and fourth wall sections ( 25 . 26 ) which converge towards each other from the outside. Bumper according to claim 4, characterized in that the third and fourth wall sections ( 25 . 26 ) wider than the first and second wall sections ( 23 . 24 ) are and edges of the third and fourth wall portions facing away from the outside ( 25 . 26 ) are immovable against each other. Bumper according to one of the preceding claims, characterized in that an area facing away from the outside ( 25 . 26 ) of the deformable element ( 20 ) on a first support ( 17 ) is attached. Bumper according to one of the preceding claims, characterized in that the deformable element ( 20 ) is a hollow profile. Bumper according to claim 7, characterized in that the hollow profile is formed from a flat material blank and two edges of the flat material blank on a first carrier ( 17 ) are attached. Bumper according to one of the preceding claims, characterized in that the first deformable element ( 20 ) behind an outer skin ( 13 ) of the bumper is arranged. Bumper according to one of the preceding claims, characterized in that the deformable element ( 20 ) is formed at least substantially in one piece, preferably one-material and over the width of the bumper ( 12 ) runs. Bumper according to one of the preceding claims, characterized by an over the first deformable element ( 20 ) second deformable element ( 16 ). Bumper according to claim 11, characterized in that the second deformable element ( 16 ) is more difficult to deform than the first deformable element ( 20 ). Bumper according to claim 11 or 12, characterized in that the second deformable element ( 16 ) comprises a hard foam body. Motor vehicle, in particular passenger cars, with a bumper, in particular a front bumper ( 12 ) according to any one of the preceding claims. Motor vehicle according to claim 14, characterized in that an edge facing the outside ( 22 ) of the first wall section ( 23 ) of the bumper extends at or below the knee height of an adult.

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