FR3103759A1 - REINFORCED BUMPER BEAM AND VEHICLE EQUIPPED WITH SUCH BEAM - Google Patents

Abstract

TITLE BUMPER BEAM WITH REINFORCEMENT AND VEHICLE EQUIPPED WITH SUCH BEAM Vehicle bumper beam (2) comprising a bumper cross member (3) formed by a profile and comprising a rear face with two shock absorber box fixing zones, a front wall (31) intended to receive the energy of the impact and having a front face opposite the rear face, a lower wall (30) disposed along a longitudinal edge of the front wall (31), extending in a general direction substantially perpendicular to said front wall (31), remarkable in that said beam (2) comprises a reinforcement (4) fixed to the cross member (3) and formed by a section profile in the shape of an “L”, one of the branches of the L forming a support wall (40) in contact with the lower wall of the cross member (30), the other branch of the L forming an extension wall (41) extending in the opposite direction to said cross member (3), preferably substantially parallel to the front wall (31) of the said cross (3). Figure for the abstract: Fig. 2

Description

REINFORCED BUMPER BEAM AND VEHICLE EQUIPPED WITH SUCH A BUMPER

The invention relates to a vehicle bumper beam comprising a reinforcement and a vehicle comprising such a beam.

A motor vehicle conventionally comprises a front bumper and a rear bumper, said bumpers comprising, inter alia, a beam extending in the transverse direction of the vehicle. Bumpers are used to improve the protection of the vehicle and its passengers in the event of an accident, more particularly during front and rear impacts.

SUV type vehicles (acronym for "Sport Utility Vehicle") are raised vehicles. When the same vehicle structure platform is used for a sedan-type vehicle and an SUV-type vehicle, the bumper beam is at different heights depending on the type of vehicle. This is due to the fact that SUV type vehicles are raised, in particular because of the larger size of their wheels. The standard shock bumpers, which are supposed to represent the reality during shocks in everyday life, are used to simulate a shock against the vehicle, and their height makes it possible to impact the bumper beam of a vehicle of height sedan type. standard. On the other hand, they are offset vertically towards the bottom of the cross member of the SUV type vehicle, and can in some cases pass below the cross member, causing a lot of damage since the cross member does not stop it in this case.

Patent FR 3064229 proposes a particular design of a bumper beam formed by a crossbeam comprising a front wall, oriented towards the front of the vehicle, closing a hollow portion extending over the length of said crossbeam, said front wall being extending downward from the hollow portion. That is to say that the front wall has zones which descend downwards, beyond the hollow part, so as to stop the standard impact buffers and prevent them from passing under the beam when this type beam is installed on an SUV type vehicle. These extensions come directly from the crosspiece.

The disadvantage of this solution is that it requires redesigning a bumper beam specifically for an SUV-type vehicle, without being able to reuse a beam conventionally used for a sedan-type vehicle. Another disadvantage is that the rigidity of the extensions, resulting directly from the material of the crosspiece, limits the possible height which can be given to these extensions. Another drawback is that the production of such a beam with localized extensions is complicated to produce from a crosspiece obtained by extrusion because it is necessary to carry out cutting operations to obtain these extensions, cuts which generate more waste.

The object of the invention is to remedy these drawbacks. In particular, one of the aims of the invention is to propose a bumper beam comprising extensions making it possible to use a crossmember common to different types of vehicle. Another objective is to propose a solution allowing the height of the extensions to be easily modified according to the type of vehicle on which the beam is intended to be installed.

This object is achieved according to the invention, thanks to a vehicle bumper beam (2) comprising a bumper crosspiece (3) formed by a profile and comprising a rear face with two zones for fixing shock absorber boxes (5) , a front wall (31) intended to receive the energy of the impact and comprising a front face opposite the rear face, a lower wall (30) disposed along a longitudinal edge of the front wall (31), extending in a general direction substantially perpendicular to said front wall (31), characterized in that said beam (2) comprises a reinforcement (4) fixed to the crosspiece (3) and formed by a section profile in the shape of an "L" , one of the branches of the L forming a bearing wall (40) in contact with the lower wall of the crosspiece (30), the other branch of the L forming an extension wall (41) extending in the direction opposite said crosspiece (3), preferably substantially parallel to the front wall (31) of said crosspiece (3).

Thus advantageously, the bumper beam can be made using a common cross member for different types of vehicles, and can be easily adapted to different types of vehicle by adding to said cross member the reinforcements specifically adapted to the vehicle on which the beam is intended to be fixed. . These reinforcements being parts added to the crosspiece, it is not necessary to redesign the crosspiece, but only to adapt the reinforcements, such as by choosing an appropriate shape and dimensions, such as by adapting the dimension of the extension wall, to obtain a specific beam for a type of vehicle, whose impact protection capacity is adapted to the type of vehicle. In addition, not being directly dependent on the manufacturing process of the crosspiece, the shape, dimensions, and possibly the material of the reinforcements can be defined with greater freedom and thus give them greater rigidity and larger dimensions. . Finally, the L-shape provides solid support on the support wall on the crosspiece, and therefore good resistance to the forces resulting from an impact.

In a preferred embodiment of the invention, the face of the extension wall (41) of the reinforcement (4) arranged opposite the bearing wall (40) is aligned with the front face of the crosspiece (3), so that the extension wall (41) extends the front wall (31).

By aligning, we mean that this face of the extension wall is in line with the front face of the crosspiece. Thus advantageously, during an impact against the vehicle, for example a front impact when the beam is arranged at the front of the vehicle, the extension wall can retain the object which collides with the vehicle at the same level as the front face of the crossbeam, when this object passes below the said crossbeam with the reinforcement arranged below the said crossbeam, the underside being in the direction of the ground on which the vehicle is placed by its wheels

In another embodiment of the invention, the reinforcement (4) comprises a stiffening element (42) between the bearing wall (40) and the extension wall (41).

Thus advantageously, in the event of impact against the extension wall, said extension wall can withstand more forces before bending towards the support wall thanks to the increased stiffness of the reinforcement given by this stiffening element.

In another embodiment of the invention, the stiffening element (42) comprises a stiffening wall (42) extending between the bearing wall (40) and the extension wall (41), substantially parallel to the direction of the junction between said support wall (40) and the extension wall (41), so as to form a hollow zone (43) delimited by the stiffening wall (42), the wall of support (40) and the extension wall (41).

Thus advantageously, all the walls being parallel to the same direction, the reinforcement with its stiffening wall can be obtained by extrusion in this direction of a material through a die having the section of said reinforcement. The manufacture of the reinforcement is thus simple and inexpensive. The reinforcement can be obtained for example by extruding an aluminum alloy.

In another embodiment of the invention, the stiffening wall (42) comprises a first flat part extending from the bearing wall (40) and perpendicular to this bearing wall (40), and a second flat part extending from the end of the first part opposite the support wall (40) to the extension wall (41), the angle between the second part and the extension wall (41 ) located opposite the bearing wall being acute, preferably less than 60 degrees.

Advantageously, this arrangement makes it possible to position the stiffening wall close to the extension wall, and thus to reduce the size of the reinforcement in a direction perpendicular to the extension wall, and therefore along the longitudinal axis of the vehicle when the beam is installed on a vehicle.

In another embodiment of the invention, the lower wall (30) comprises a border (32) at the level of its junction with the front wall (31), extending in the extension of the said front wall (31) and projecting relative to said lower wall (30) in the direction of the reinforcement (4), the support wall (40) comprising on its face located opposite the lower wall (30) a positioning means ( 44) cooperating with the border (310).

Thus advantageously, the reinforcement can be positioned in a simple manner on the lower wall and in a direction perpendicular to the front wall of the crosspiece without requiring the addition of parts or the use of particular positioning tools by causing the positioning means to cooperate directly with the border.

In another embodiment of the invention, the positioning means (44) is a positioning rib (44) projecting from the support wall (41) towards the lower wall (30), substantially parallel at the junction between the support wall (40) and the extension wall (41), resting against the edge (32).

Thus advantageously, this positioning rib can be obtained directly during manufacture by extrusion of the reinforcement, at the same time as the bearing walls, extension wall, and possibly the reinforcing wall.

In another embodiment of the invention, the crosspiece (3) is a profile comprising a rear wall (33) substantially parallel to the front wall (31), the lower wall connecting the front wall (31) and the rear wall (33) along one of their lower longitudinal edge, an upper wall (34) connecting said front (31) and rear (33) walls along their respective upper longitudinal edge opposite their lower longitudinal edge, so that the crosspiece forms a section with a hollow body extending over the entire length of said crosspiece (3), the rear wall (33) comprising the rear face.

Thus advantageously, the crosspiece (3) is of high rigidity.

In another embodiment of the invention, the reinforcement (4) is fixed to the crosspiece (3) by weld beads between the bearing wall (40) and the crosspiece (3). Thus, advantageously, the attachment of the reinforcement to the crosspiece is particularly solid.

The invention also relates to a vehicle (1) comprising a bumper beam as described above.

Thus advantageously, the vehicle can be equipped with a beam adapted to its type of vehicle, at a lower cost, while having a beam offering good protection against impact.

The invention will be better understood on reading the following description, given solely by way of example and made with reference to the appended drawings, in which:

- is a view of the front of a vehicle comprising a bumper beam according to the invention.

- is a view of the bumper beam according to the invention in a side view of the vehicle.

- is a perspective view of the underside of the bumper beam, at the level of one of the reinforcements.

The drawings are schematic representations to facilitate understanding of the invention. Components may not be shown to scale. The same references correspond to the same components from one figure to another.

In the description, the vertical is taken with reference to the vertical axis of the vehicle. Top and bottom are taken in reference to the top and bottom of the vehicle.

FIG. 1 illustrates the front of a vehicle 1 comprising a bumper beam 2 according to the invention, fixed to the vehicle 1 by two shock absorber boxes 5. The beam 2 comprises a crosspiece 3 extending in the direction transverse to the vehicle 1, and which is slightly curved so as to follow the curvature of the front of the vehicle. Three reinforcements 4 are positioned under the crosspiece 3, a first reinforcement being located in the middle of the length of the crosspiece 3, the length of the beam being the dimension of the beam in the transverse direction of the vehicle 1, the other two on either side others of this first reinforcement 4, at the level of the attachment zone of the shock absorber boxes 5.

As illustrated in Figure 2, the crosspiece 3 is a profile comprising a front wall 31, on the side of the front of the vehicle 1, substantially vertical, a rear wall 33 remote from the front wall 31, behind the front wall 31, c that is to say further towards the rear of the vehicle 1, and a lower wall 30 and upper 34 connecting the front wall 31 to the rear wall 33. That is to say that the rear wall 33 is arranged between the front wall 31 and the structure of the vehicle. The upper wall 34 interconnects the upper longitudinal edges of the front wall 31 and the rear wall 33, that is to say in the upper part of the crosspiece 3, and the lower wall 30 interconnects the lower longitudinal edges of the front wall 31 and the rear wall 33, that is to say in the lower part of the crosspiece 3.

The crosspiece 3 comprises a hollow body extending over its entire length, delimited by the front wall 31, the rear wall 33, the lower wall 30 and the upper wall 34. The lower wall 31 closes the hollow body in the lower part of the crosses 3, and the upper wall 34 in the upper part. In the embodiment of Figure 2, an inner wall 35 extends between the front wall 31 and the rear wall 33, at a substantially equal distance from these two lower 31 and upper 33 walls, separating the hollow body inside of crosspiece 3 into two cells. This type of crosspiece 3 is made, for example, of aluminum alloy by extrusion and then bending in order to give it the desired curvature.

The shock absorber boxes 5 are fixed to a rear face of the crosspiece 3 facing the rear of the vehicle 1, this rear face being a face of the rear wall 33. The shock absorber boxes 5 are for example fixed to the wall rear 33 by weld beads, or by screw-nut systems.

The reinforcement 4 is a section whose section has an "L" shape, that is to say it comprises two non-parallel branches, for example substantially perpendicular to each other as in the embodiment illustrated in the figures , and connected at their end. One of the branches forms a support wall 40 and the other branch an extension wall 41. The support wall 40 is fixed to the crosspiece 3 so as to bear against the lower wall 30. The wall extension 41, perpendicular to the support wall 40, extends substantially vertically in the opposite direction to the crosspiece 3. In the embodiment illustrated in Figures 2 and 3, the extension wall 41 is aligned with the front wall 31 of the crosspiece 3, so as to create a downward extension of the vehicle 1 aligned with the front wall 31, the face of the extension wall 41 oriented towards the front of the vehicle 1 being aligned with the face of the front wall 31 facing the front of the vehicle 1.

In a variant not shown, the extension wall 41 of the reinforcement 4 can be offset along the longitudinal axis of the vehicle 1 relative to the front wall 31, for example towards the rear of the vehicle 1.

In FIG. 2, the lower wall 30 is curved towards the inside of the crosspiece 3. The bearing wall 41 of the reinforcement 3 bears on this lower wall 30, at the level of the junctions of this lower wall 30 with the wall front 31 and with the rear wall 33. The part of the lower wall 30 between these two junctions is not in contact with the support wall 40.

The reinforcement 4 comprises a stiffening element 42 between the bearing wall 40 and the extension wall 41. In the embodiment of FIGS. 2 and 3, the stiffening element 42 is a stiffening wall 42 which comprises a first flat part 421 extending from the bearing wall 40, perpendicular to this bearing wall 40 and substantially parallel to the extension wall 41 which is itself perpendicular to the bearing wall 40, followed by a second flat part 422 connecting the first part 421 to the extension wall 41. The angle between the second part 422 and the extension wall 41 oriented on the side of the support wall 40 is an acute angle, it is less than 90 degrees. To obtain good stiffening, this angle can be chosen for example less than or equal to 60 degrees. The first part 421 of the stiffening wall 42 being remote from the extension wall 41, said extension wall 41, the stiffening wall 42 and the bearing wall 40 define a hollow zone 43.

The first part 421 and second part 422 are in planes parallel to the direction given by the junction between the bearing wall 40 and the extension wall 41, so that the whole of the reinforcement 4 can be produced by extrusion according to this direction defined by this junction.

As a variant, the stiffening element 42 is a plane wall placed at an angle with respect to the support wall 40 and the extension wall 41, parallel to the junction between the support wall 40 and the extension wall. 41, so that the entire reinforcement 4 can be produced by extrusion in a direction parallel to the direction defined by this junction. The section of the hollow zone 43 in a plane perpendicular to the support wall 40 and the extension wall 41 is then triangular in shape. This shape of the stiffening element provides great rigidity to the reinforcement 4. By choosing the bearing 40 and extension 41 walls perpendicular to each other, the section of the hollow zone 43 forms a right-angled triangle.

The reinforcement 4 is fixed to the crosspiece 3 by weld beads 6. In FIG. 2, the bearing surface 40 extends over the entire width of the crosspiece 3, that is to say from the junction of the lower face 30 with the front face 31 as far as the junction of the lower face 30 with the rear face 33. The lower face 30 being curved towards the inside of the crosspiece 3, the support wall 40 of the reinforcement 4 is in contact with the crosspiece 3 only at the level of the junctions of this lower face 30 with the front face 31 and with the rear face 33. The weld beads 6 are arranged at the level of its junctions, overflowing on the front wall 31 and on the rear wall 33.

In a variant not shown, the bottom wall 30 may be flat and the bearing wall 40 in contact over its entire surface with this bottom wall 30. In this variant, the weld bead 6 may extend along this bottom wall 30.

The extension wall 31 is for example of a height greater than 50 mm, the height being the dimension of the extension wall 41 along the vertical direction of the vehicle 1 when the beam 2 is installed on the vehicle 1.

In the embodiment presented in FIG. 3, the lower wall 30 comprises a border 32 at the level of its junction with the front wall 31, extending downwards in the extension of said front wall 31. The reinforcement 4 comprises a means positioning 44 cooperating with the edge 32 allowing positioning in the longitudinal direction to the vehicle of said reinforcement on the underside 31. As illustrated in this figure 3, the positioning means 44 is a rib 44 projecting from the support wall 30 towards the crosspiece 3. The positioning of the reinforcement 4 is obtained by bringing this rib 44 into abutment against the border 32. In FIG. 3, the rib 44 is in abutment against the border 32, on the side of this border 32 oriented towards the wall rear 33. The rib 44 is parallel to the junction between the support wall 40 and the extension wall 41, so that the whole of the reinforcement 4 with this rib 44 can be produced by extrusion. Other abutting positions are possible.

Other positioning means known to those skilled in the art are applicable.

In the embodiment of the figures, the lower 30, upper 34 and inner 35 walls are curved so as to better control their deformation in the event of impact and to optimize the absorption of energy by their deformation.

Other shapes of crosspiece 3 comprising a front wall 31 and a bottom wall 30 can be used, with a reinforcement 4 fixed to the bottom wall 30. For example, the crosspiece 3 can be a section profile in the shape of an "L" , or even a "U" arranged horizontally so that the two branches of the "U" are horizontal to form the lower wall 30 and an upper wall 33 connected by a front wall 31.

Figures 1 through 3 illustrate a beam at the front of a vehicle. Such a beam 2 can also be applied to the rear of the vehicle 1, the front wall 31 being in this case oriented towards the rear of the vehicle 1 and the rear wall 33 towards the front of the vehicle.

Claims (10)

Vehicle bumper beam (2) comprising a bumper crossmember (3) formed by a profile and comprising a rear face with two zones for fixing shock absorber boxes (5), a front wall (31) intended to receive the impact energy and comprising a front face opposite the rear face, a bottom wall (30) disposed along a longitudinal edge of the front wall (31), extending in a general direction substantially perpendicular to said front wall ( 31), characterized in that said beam (2) comprises a reinforcement (4) fixed to the crosspiece (3) and formed by a section profile in the shape of an "L", one of the branches of the L forming a wall of support (40) in contact with the lower wall of the crosspiece (30), the other branch of the L forming an extension wall (41) extending in the opposite direction to the said crosspiece (3), preferably substantially parallel to the front wall (31) of said crosspiece (3). Bumper beam (2) according to the preceding claim, in which the face of the extension wall (41) of the reinforcement (4) arranged opposite the support wall (40) is aligned with the front face of the crossbar (3), so that the extension wall (41) extends the front wall (31). Bumper beam (2) according to one of the preceding claims, the reinforcement (4) of which comprises a stiffening element (42) between the support wall (40) and the extension wall (41). Bumper beam (2) according to Claim 3, the stiffening element (42) of which comprises a stiffening wall (42) extending between the support wall (40) and the extension wall (41), substantially parallel to the direction of the junction between said support wall (40) and the extension wall (41), so as to form a hollow zone (43) delimited by the stiffening wall (42), the wall of support (40) and the extension wall (41). Bumper beam (2) according to Claim 4, the stiffening wall (42) of which comprises a first flat part extending from the bearing wall (40) and perpendicular to this bearing wall (40), and a second planar part extending from the end of the first part opposite the support wall (40) to the extension wall (41), the angle between the second part and the extension wall ( 41) located opposite the bearing wall being sharp, preferably less than 60 degrees. Bumper beam (2) according to one of the preceding claims, the lower wall (30) of which comprises a border (32) at the level of its junction with the front wall (31), extending in the extension of the said front wall (31) and projecting relative to said lower wall (30) in the direction of the reinforcement (4), the bearing wall (40) comprising on its face located opposite the lower wall (30) a positioning means (44) cooperating with the edge (310). Bumper beam (2) according to the preceding claim, the positioning means (44) of which is a positioning rib (44) projecting from the support wall (41) towards the lower wall (30), substantially parallel to the junction between the support wall (40) and the extension wall (41), resting against the edge (32). Bumper beam (2) according to one of the preceding claims, the crosspiece (3) of which is a profile comprising a rear wall (33) substantially parallel to the front wall (31), the lower wall connecting the front wall (31) and the rear wall (33) along one of their lower longitudinal edge, a top wall (34) connecting said front (31) and rear (33) walls along their respective upper longitudinal edge opposite their longitudinal edge lower, so that the crosspiece forms a profile with a hollow body extending over the entire length of said crosspiece (3), the rear wall (33) comprising the rear face. Bumper beam (2) according to one of the preceding claims, the reinforcement (4) of which is fixed to the crossbeam (3) by weld beads between the support wall (40) and the crossbeam (3) . Vehicle (1) comprising a bumper beam according to one of the preceding claims.