DE102010011494A1 - Front or rear bumper supporting structure for use in motor vehicle, has blank flange inserted between longitudinal and transverse beams and fastened to longitudinal beams, where flange stays in laminar contact with side of one of brackets - Google Patents

Abstract

The structure has a bumper transverse beam (1) comprising upper and lower brackets (2, 3) and arranged at front ends of longitudinal beams. A blank flange (6) is inserted between the longitudinal and transverse beams and fastened to the longitudinal beams and end sections (4, 5) of the brackets. The blank flange stays in laminar contact with a plane rear side (15) of one of the brackets. The brackets are designed as square end-profiles, and sides of the brackets are fastened to each other, where the front ends of the longitudinal beams are designed as crash-boxes.

Description

The present invention relates to a bumper support structure that supports a front or rear bumper in the event of a collision inside a motor vehicle body.

In most modern motor vehicles, the bumper is a shell-like, usually molded plastic element, which surrounds the lower bow or tail area of the vehicle body and is designed to initially afford little resistance to deformation in a collision and thus possibly a pedestrian gently to be able to catch. In order to adequately protect the occupants of the vehicle in a collision with another motor vehicle or other hard obstacle, such a bumper is generally supported by a bumper cross member via an intermediate upset zone, the bumper cross member having a high deformation resistance and being able to to at least partially dissipate the energies released in a collision with a hard, heavy obstacle.

In order to be able to effectively initiate the forces occurring in such a collision in other loadable parts of the vehicle body, such a bumper cross member is generally mounted on the front ends of body longitudinal beams and extends horizontally at the level of these front ends.

There are bumper support structures are known in which in addition to a extending at the level of the front ends of body longitudinal beams main bumper cross member, an auxiliary cross member is provided which is disposed below the main bumper cross member and protrudes relative to this forward. The purpose of this auxiliary cross member is to detect in a collision with a pedestrian this first, by means of a supported by the auxiliary cross member area of the bumper, at the level of his lower leg and thereby let him fall as possible on the hood. The strength of such auxiliary cross member is considerably lower than that of the main cross member, firstly, because a low compared to the main crossbar load capacity of the auxiliary cross member, so that this can fulfill its intended task, on the other hand, because of considerable vertical misalignment between the auxiliary cross member and the longitudinal body of the body makes it difficult to introduce large forces, which may become relevant for occupant protection in a collision, via the auxiliary cross member into the body longitudinal members.

The height at which a bumper cross member extends in a motor vehicle body is largely determined by the requirement that this height should be substantially the same for all vehicles, such that in a collision between two vehicles, the bumper cross member of one does not submerge under that of the other and thereby both lose their effect. This height corresponds to many vehicles, the installation height of a radiator, with the result that the bumper cross member or supported by him parts of a bumper obstruct the fresh air flow to the radiator.

Out DE 41 19 638 C1 a bumper support structure for a motor vehicle is known in which a bumper cross member is divided into an upper and a lower bracket. The stirrups of substantially semi-cylindrical cross section are received in semicircular recesses at a front end of a body longitudinal beam and welded at their flat front sides to a plate which overlies the open front end of the body longitudinal beam and is bolted to flanges angled from the front end. If in a collision one of the stirrups is loaded centrally, a bending moment occurs due to the vertical offset between the middle region and the ends of the stirrup on the plate. Since the plate is secured at its upper and lower edges to the flanges of the longitudinal member, it can only yield to the bending moment by a middle portion of the plate bulges forward. Thus, the brackets can rotate in a collision without deforming and without evading energy by the deformation of the collision. It is therefore lost for the occupant protection required crumple zone.

Object of the present invention is to provide a bumper support structure, which allows an effective supply of fresh air to a radiator behind him while ensuring effective occupant protection.

The object is achieved by a respective end flange inserted between the two side members and the bumper cross member in a bumper support structure with a bumper cross member comprising an upper and a lower bracket, as well as two side rails, at the front ends of the bumper cross member, and on the side member and is secured to end portions of the stirrups, and the end flange is in surface contact with at least one flat back of at least one of the stirrups. A rotation of a bracket about an axis extending in the vehicle transverse direction without simultaneous bending of the bracket is only possible if the back of the bracket separates from the end flange, but would have to tear the attachment of the bracket on the end flange, which requires a considerable effort in appropriate design of the attachment.

In order to dissipate collision energy introduced via the bumper cross member in a front region of the vehicle body without affecting the passenger compartment, the front ends of the longitudinal members are expediently designed as crash boxes.

The brackets that form the bumper cross member are preferably formed as square profiles. Such profiles are on the one hand inexpensive available, on the other hand, the angular cross-sectional shape facilitates a stable torque load attachment of the bracket.

According to a first preferred embodiment, at least one of the brackets is open at the level of its end sections on a front side opposite the rear side. This allows easy access from the front to the back of the bracket to secure it - by screws, welding or other suitable means - to the end plate.

When two mutually contacting flanks of the stirrups are secured together, a torque acting on one of the stirrups can also be transmitted to the second, so that the attachment of the second stirrup to the end flange can contribute to the resistance of the first stirrup to rotation.

In order to increase the torque load capacity with little use of material, it is also expedient that a cover is attached to both brackets.

A cover spanning the front sides of the brackets may also be fastened to the end flange.

According to another embodiment, at least one groove is formed at the end flange into which one of the stirrups is inserted in a non-rotatable manner.

Preferably, such a groove is oriented horizontally in order to compensate for any dimensional tolerances by moving the groove and strap against each other when attaching the bracket to the end flange.

If the end flange has two grooves for both stirrups, one of the ends of the side member may engage in a space between the grooves. In this way, a lot of space for a compression of the longitudinal member, in particular of the front end of the longitudinal member forming crash box, can be provided.

Further features and advantages of the invention will become apparent from the following description of embodiments with reference to the accompanying figures. Show it:

1 a perspective view of a bumper support structure according to a first embodiment of the invention;

2 a section through the support structure along the level II-II 1 ;

3 a partial view of a bumper support structure according to a second embodiment of the invention;

4 one too 2 analog section through the bumper support structure of 3 ;

5 a partial view of a bumper support structure according to a third embodiment of the invention;

6 one too 2 analog section through the bumper support structure of 5 ;

7 a perspective view of a bumper support structure according to a fourth embodiment of the invention;

8th an enlarged detail of the structure of the 7 ;

9 one too 2 analog section through the bumper support structure of 7 ;

10 a horizontal section through the bumper support structure of 7 ;

11 a partial view from behind of a structure according to a variant of the fourth embodiment;

12 a perspective view of a bumper support structure according to a fifth embodiment of the invention; and

13 a section through the structure of 12 along the plane XIII-XIII.

1 shows a perspective view of a bumper support structure according to a first embodiment of the invention, and 2 shows a cross section through the bumper support structure of 1 along the level II-II 1 , A bumper cross member 1 is composed of an upper bracket 2 and a lower bracket 3 , the each formed of a square profile of steel or aluminum. end 4 . 5 the coat hanger 2 . 3 are about one in 1 concealed end flange 6 attached to a body longitudinal member, of which in the 1 just a crash box forming its front end 7 is shown. The end flange 6 is at an open front end of the crashbox 7 welded to close this. The bumper itself is not shown. It is not permanently connected to the bumper support structure and supported by the latter substantially only in the horizontal direction, in the event of a collision.

A middle section 9 of the lower bracket 3 is relative to the end sections 5 offset downwards and arched forward curved. A middle section 8th of the upper temple 2 is relative to its end sections 4 offset upwards so that both stirrups 2 . 3 together a passage 10 limit. The passage 10 forms together with an overlapping with him opening of the (not shown) bumper a fresh air duct, the center of a behind the bumper cross member 1 arranged cooler opens. Vertical struts 11 can between the sections 8th . 9 be attached to the entire bumper crossmember 1 to stiffen.

A front side 17 of the temple 2 jumps in its middle section 8th in comparison to the front 17 of the lower bracket 3 back slightly to that of the bumper crossmember 1 held bumper give a slightly fleeing profile, which in a collision with a pedestrian, this fall on the bonnet rather than on the road ahead of the vehicle.

The fronts 17 the coat hanger 2 . 3 are in the end sections 4 . 5 cut away, and upper and lower horizontal flanks 12 . 13 the coat hanger 2 . 3 are increasingly tapered towards their outer ends in order to adapt to a rounded in plan view outer shape of the bumper. The absence of the front pages 17 the coat hanger 2 . 3 at the end sections 4 . 5 facilitates access to screws 14 that like in 2 shown holes in the back 15 the coat hanger 2 . 3 and in the end flange 6 prevail over the hangers 2 . 3 on the end flange 6 to fix.

The backsides 15 the coat hanger 2 . 3 are through the screws 14 in surface contact with the end flange 6 held. Horizontal flanks 12 . 13 the coat hanger 2 . 3 touch each other and are at theirs from the termination flange 6 facing away from the front edges by a continuous weld 16 connected. If in a collision, only one of the two brackets 2 . 3 is loaded, for example, the lower bracket 3 by a force F, as in 2 shown, then it is easy to understand that the attachment of the temple 3 on the end flange 6 it's the temple 3 impossible to avoid the force by a rotational movement. A continuous welding of the end flange 6 with the front edge of the crash box 7 Prevents yielding by bending the end flange 6 , Every yielding of the temple 3 under the force F is only in the context of a deformation of the bracket 3 possible even at the front edges of the horizontal flanks 12 . 13 of the temple 3 dodge down. The connection through the weld 16 It brings with it that the top bracket 2 with being deformed and that too the screws 14 holding the upper temple 2 at the end flange 6 fix, be claimed on train. This is how the upper bracket bears 2 to the load capacity of the lower bracket 3 at, and vice versa, the lower stabilizes the upper bracket 2 if it alone is subjected to a deforming force.

3 shows in a partial perspective view of a half of a bumper support structure according to a second embodiment of the invention, and 4 shows a section along the plane IV-IV in 3 , The shape of the temples 2 . 3 is substantially the same as in the first embodiment; One difference is that the fronts 17 the two stirrups 2 . 3 extending here over the entire width of the structure. To access the screws 14 to allow are only single with the screws 14 aligned openings 18 in the front pages 17 cut. As based on 4 to recognize the one to 2 analogue section through the construction of the 3 shows that runs the hanger 2 . 3 connecting weld 16 here directly in the plane of the front pages 17 ,

The 6 and 7 show a third embodiment of the bumper support structure, based on the embodiment of 1 and 2 based. Like there are the fronts 17 the coat hanger 2 . 3 at the level of the end sections 4 . 5 removed, and the horizontal flanks 12 . 13 rejuvenate to the sides. A lid 19 in the form of a substantially flat plate 20 with up and down angled edge bars 21 covers the open front sides of the stirrups 2 . 3 , The plate 20 is with openings 18 to access the screws 14 Mistake.

Like the cross section of the 6 shows, the lid forms 19 a clamp that holds each hanger 2 or 3 forces one to at least partially follow one another's deformation. To jump off the lid 19 To prevent stress, the edge bars 21 on the flanks facing away from each other 12 . 13 the two stirrups 2 . 3 through welds 22 attached. A weld 16 that like in 2 represented the touching flanks 12 . 13 the coat hanger 2 . 3 attached to each other, is in 6 Although not shown, but may also be provided.

A not-drawn, simplified modification, according to the edge webs of the lid 19 omitted, and instead are the top and bottom edges of the plate 20 at the front edges of the mutually remote horizontal flanks 12 . 13 the two straps 2 . 3 welded.

7 shows a perspective view of a bumper support structure according to a third embodiment of the invention. In addition to the bumper cross member already considered in the foregoing embodiments 1 with an upper and lower bracket 2 respectively. 3 is in 7 additionally an auxiliary crossbeam 23 shown below the lower bracket 3 extends and a little further than this projecting forward to capture, as described above, in a collision with a pedestrian whose lower leg and let him tilt on the hood. Such in any suitable manner connected to the side member auxiliary cross member 23 can also be used in the embodiments considered above.

A second special feature of the design of the 7 is that the two stirrups 2 . 3 in their middle sections 8th . 9 not, or, as can be seen from the enlarged detail of the 8th results, only slightly against the end sections 4 . 5 are vertically offset. The end sections 4 . 5 are in horizontal grooves of a carrier plate 24 taken, with side walls facing each other 25 the grooves a bag open to the vehicle interior 26 limit, in which, in particular from the sectional representation of 9 becomes clear from behind the crash box 7 intervenes.

The temples 2 . 3 are in the grooves of the carrier plate 24 displaceable in the vehicle transverse direction, as long as they are not through welds 27 attached to it. This creates the possibility of compensating for tolerances in the dimensions of its components and the spacing of the longitudinal members from one another during assembly of the support structure.

The construction of the connection between the temples 2 . 3 and the crashbox 7 becomes clearer from the horizontal section of the 10 , Horizontal walls 28 the crashbox 7 grab in the bag 26 and lie at the bottom, ie at one of the side walls 25 connecting portion of the support plate 24 , at. side walls 29 The crashbox can be placed in one over the leading edges of the horizontal walls 28 projecting forward portion be bent sideways to flanges 30 to form, at which the carrier plate 24 by screws 14 is attached, as in 10 the example of the right side wall 29 shown. Alternatively, the flanges 30 also through to the side walls 29 welded, riveted or fastened in any other suitable manner angle elements may be formed, as in the example of the left side wall 29 shown. This is how the carrier plate represents 24 at the same time a termination flange for the crash box 7 dar. The installation locations of the screws 14 that the backing plate 24 with the flanges 30 connect, are easy to access from the front. The flanges 30 are oriented parallel to each other in the vehicle transverse direction, but offset in the vehicle longitudinal direction against each other to account for the curvature of the bumper cross member.

Alternatively, there is also the in 11 shown possibility on the open front end of the crash box 7 a plate 31 To weld, from the laterally projecting portions as flanges 30 act, leaving this plate 31 and the carrier plate 24 together form a termination flange.

As in particular on the basis of the detailed representation of 8th to recognize, are the hangers 2 . 3 in the grooves of the carrier plate 24 rotatably received, so that the hanger 2 . 3 a collision force acting from the front could at most then escape by a rotation about a horizontal axis, if at the same time the grooves of the carrier plate 24 be bent up.

A bending of these grooves can be prevented in different ways, or at least made more difficult, for example by welding the bracket 2 . 3 on the walls 25 the groove through welds 27 , or, by, as in 12 shown the end sections 4 . 5 the coat hanger 2 . 3 a lid 32 slipped over, like the lid 19 of the 5 and 6 a central plate 20 and angled edge bars 21 includes. Two open-edged cutouts on the right and left edges of the central plate leave the screws 14 free and give the central plate 20 the shape of a horizontal H. In particular, a welding of these edge bars 21 at the edges of the carrier plate 24 as by welds 33 in 13 As illustrated, the bumper beam structure imparts a high degree of rigidity in the event of an uneven fit on the stirrups 2 . 3 distributed burden.

LIST OF REFERENCE NUMBERS

1

Bumper crossmember

2

upper temple

3

lower temple

4

end

5

end

6

Abschnittsflansch

7

crash box

8th

middle section

9

middle section

10

passage

11

strut

12

horizontal flank

13

horizontal flank

14

screw

15

back

16

Weld

17

front

18

opening

19

cover

20

plate

21

edge web

22

Weld

23

Auxiliary crossbeam

24

support plate

25

Side wall

26

bag

27

28

horizontal wall

29

Side wall

30

flange

32

cover

33

WeldingSpot

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 4119638 C1 [0006]

Claims (10)

Bumper support structure with a bumper crossmember ( 1 ), which has an upper and a lower bracket ( 2 . 3 ), and with two longitudinal members, at the front ends of the bumper cross member ( 1 ), characterized in that between the two longitudinal members and the bumper cross member ( 1 ) one end flange each ( 6 ; 24 ; 24 . 31 ) and at the longitudinal beam and at end portions ( 4 . 5 ) the coat hanger ( 2 . 3 ) and that the end flange ( 6 ; 24 ; 24 . 31 ) in surface contact with at least one flat rear side ( 15 ) at least one of the brackets ( 2 . 3 ) stands. Bumper support structure according to claim 1, characterized in that the front ends of the longitudinal members as crash boxes ( 7 ) are formed. Bumper support structure according to claim 1 or 2, characterized in that the brackets ( 2 . 3 ) are designed as square profiles. Bumper support structure according to one of the preceding claims, characterized in that at least one of the brackets ( 2 . 3 ) at the level of its end sections ( 4 . 5 ) on one of the back ( 15 ) opposite front side ( 17 ) is open. Bumper support structure according to one of the preceding claims, characterized in that two mutually contacting flanks ( 12 . 13 ) the coat hanger ( 2 . 3 ) attached to each other ( 16 ) are. Bumper support structure according to one of the preceding claims, characterized in that a cover ( 19 ) Front sides ( 17 ) of both arms ( 2 . 3 ) overlapping the temples ( 2 . 3 ) is attached. Bumper support structure according to claims 1 to 5, characterized in that one of the front sides of the bracket ( 2 . 3 ) spanning lid ( 32 ) at the end flange ( 24 . 31 ) is attached. Bumper support structure according to one of the preceding claims, characterized in that at the end flange ( 24 ) is formed at least one groove into which one of the bracket ( 2 . 3 ) is inserted non-rotatably. Bumper support structure according to claim 8, characterized in that the groove is oriented horizontally. Bumper support structure according to claim 8 or 9, characterized in that one of the ends ( 7 ) of the longitudinal member in a space ( 26 ) between two grooves of the end flange ( 24 ) intervenes.

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