Optimized bumper frame for improved pedestrian impact.

Abstract

The invention relates to a bumper support frame (1) for the front panel, designed to support, when fixed to the front panel, a bumper reinforcement. The frame (1) comprises a transverse portion (4) designed to extend in a transverse direction. The frame (1) comprises at least one foot (6) extending from the transverse portion (4) to an end (7), adapted to provide a fusible attachment of the reinforcement to the frame (1). The frame (1) comprises at least one energy-absorbing element (10) projecting from said transverse portion (4). Each energy-absorbing element (10) is designed to absorb, when the frame (1) is mounted on the front panel, a portion of the energy of a frontal impact experienced by the front panel by deforming in order to limit the recoil of at least a portion of the reinforcement fixed to the frame (1) in the front panel under the effect of the frontal impact. (Figure 1)

Description

Title of the invention: Bumper frame optimized for improved pedestrian impact.

[0001] The technical field relates to bumper frames designed to fix a bumper on a front face of a motor vehicle, front faces having such a frame to support the bumper as well as vehicles having such a front face.

[0002] In the area of ​​road safety, car manufacturers must consider numerous concerns and regulations when developing new vehicles. Thus, car manufacturers must ensure the safety of vehicle occupants in the event of a collision, but also protect other vulnerable road users such as pedestrians. Finally, it is necessary to control the repair costs of vehicles subjected to urban impacts, known as repairability impacts, which occur at low speeds of around 15 to 20 kilometers per hour. The behavior of motor vehicles in these three situations is regulated and tested using standardized testing procedures. The requirements for the results of these tests are constantly increasing and becoming more difficult to meet, forcing car manufacturers to innovate continuously.Furthermore, standardized tests are regularly updated. For example, a new test protocol, called the enhanced pedestrian impact test, involves projecting a vehicle into a special pole divided into three overlapping zones, simulating a pedestrian's leg. The ideal behavior expected of the vehicle projected against such a pole must differ depending on the zone considered and offer different rigidity depending on the height. It is necessary to meet the requirements of a repairability test, in particular by preserving the motor-fan assembly in the upper part of the front end, but also to limit the potential injuries to a pedestrian's leg in the event of an impact.

[0003] Vehicles equipped with bumper reinforcements are already known in the prior art and ensure adequate behavior in the event of a repairable collision as well as in the event of a pedestrian impact. However, such front ends can still be improved, particularly with regard to their behavior in the event of an improved pedestrian impact.

[0004] In this technical context, an object of the present invention is to provide a bumper support frame that improves behavior in the event of an enhanced pedestrian impact by allowing differentiation of rigidity according to the height of impact on the front face.

[0005] To this end, the present invention relates to a bumper support frame for the front of a motor vehicle, designed to support, when fixed to the front, a bumper reinforcement, the frame comprising a transverse part designed to extend in a transverse direction from the front, the frame comprising at least one foot extending from the transverse part towards one end, suitable for ensuring a fusible attachment of the bumper reinforcement to the frame, the frame being characterized in that it comprises at least one absorber element projecting from said transverse part, each absorber element being designed to absorb, when the frame is mounted on the front, a part of the energy of a front impact suffered by the front by deforming in order to limit the recoil in the front, under the effect of the front impact, of at least a part of the bumper reinforcement fixed to the frame.

[0006] The invention also relates to a front face of a vehicle comprising a frame according to the invention.

[0007] The invention also relates to a vehicle comprising at least one front face according to the invention.

[0008] Thus, a frame according to the invention makes it possible to assemble a front end of a vehicle according to the invention that offers the advantages known for vehicles with a conventional frame. Thus, in the event of a pedestrian impact, the failure of the foot allows the bumper reinforcement to retract within the front end, thereby ensuring adequate pedestrian impact behavior. The presence of at least one energy-absorbing element allows for the absorption, in the upper part of the front end, of a greater amount of energy released during a frontal impact compared to a conventional frame, and limits the retraction of the bumper reinforcement within the front end, towards the motor-fan assembly. Indeed, the retraction of the reinforcement towards the motor-fan assembly requires prior deformation of each energy-absorbing element. The behavior of the front end during an improved pedestrian impact is therefore enhanced since the rigidity of the front end varies according to the height of the impact.Furthermore, the increased rigidity in the upper part of the front face, at the transverse level, improves the rigidity perceived by a vehicle user.

[0009] According to one embodiment of the invention, at least one absorber element has a fixing interface designed to allow the bumper reinforcement to be fixed to the absorber element.

[0010] According to one possibility, each absorbing element forms an absorption chamber.

[0011] Advantageously, each box has a truncated conical shape, in particular a truncated conical shape with a rectangular base.

[0012] According to one embodiment, each end of each foot has indexing means designed to index and fix the reinforcement relative to the frame.

[0013] Advantageously, the indexing means include a fastening strap.

[0014] Advantageously, each fastening strap is fusible so as to break under the effect of a front impact suffered by the front face in order to release the bumper reinforcement.

[0015] The invention will be better understood upon reading the following detailed description, given solely by way of non-limiting example and made with reference to the accompanying drawings in which:

[0016] [Fig-1] [Fig.1] represents a perspective view of a support frame for a... shocks according to the invention;

[0017] [Fig.2] Fig.2 represents a perspective view of a front face showing a bumper reinforcement mounted on the frame of the [Fig.l];

[0018] [Fig.3] [Fig.3] represents a detailed view of the armature indexing means of the [Fig.l].

[0019] In these figures, the same references are used to designate the same elements.

[0020] A bumper support frame 1 according to the invention, illustrated in [Fig. 1], is intended to be mounted on the front end 2 of a motor vehicle, illustrated in [Fig. 2]. In particular, the frame 1 is designed to be fixed to the metal structure of the front end 2. The frame 1 is designed to support, when fixed to the front end 2, a bumper reinforcement 3 and / or a bumper skin, not shown in the figures. The bumper reinforcement 3 strengthens the bumper skin, notably by stiffening certain areas of the latter. The frame 1 is, for example, made of molded plastic. The bumper reinforcement 3 is, for example, made of molded plastic.

[0021] The frame 1 comprises a transverse portion 4 designed to extend along a transverse direction T, illustrated in [Fig. 2], from the front face 2. The transverse portion 4 is curved along the transverse direction T, as illustrated in Figures 1 and 2. On the one hand, extending from the transverse portion 4, the frame 1 has a substantially flat upper portion 5, designed to contribute to the attachment of the frame 1 to the front face 2 and to cover at least part of a motor-fan assembly (not shown) of the front face 2. On the other hand, the frame 1 comprises at least one foot 6, in this case three feet 6, extending from the transverse portion 4 to an end 7, adapted to provide a fusible attachment of the bumper reinforcement 3 to the frame 1. By fusible attachment, it is understood that an attachment is designed to break in the event of a frontal impact to the front face 2, the intensity of which exceeds one predetermined threshold intensity.All the ends 7 of the feet 6 are connected together by a lower cross member 8. Each end 7 of each foot 6 has, for example, indexing means 9 allowing the reinforcement 3 to be indexed and fixed relative to the frame 1. In order to obtain the fusible fixing of the reinforcement 3, . Each foot 6 is shaped to break, in the event of a front impact suffered by the front face 2 with an intensity greater than a predetermined threshold, in order to detach the reinforcement 3 from the frame 1 and allow the movement of the reinforcement 3.

[0022] As illustrated in [Fig.1], the frame 1 comprises at least one absorber element 10 projecting from said transverse part 4. In this case, the frame 1, illustrated in the figures, has six absorber elements 10 distributed in two groups arranged symmetrically along the transverse part 4.

[0023] In the described embodiment, each absorber element 10 forms an absorption chamber 11. Advantageously, each chamber 11 has a frustoconical shape, in particular a frustoconical shape with a rectangular base.

[0024] Each absorber element 10 is designed to absorb, when the frame 1 is mounted on the front face 2, a part of the energy of a front impact suffered by the front face 2 by deforming in order to limit the recoil, in the front face 2 under the effect of the front impact, of at least a part of the bumper reinforcement 3 fixed on the frame 1.

[0025] As illustrated in [Fig. 1], at least one absorber element 10, in this case the absorber elements 10 located on the edges of the transverse part 4, each have a fastening interface 12 designed to allow the bumper reinforcement 3 to be attached to the absorber element 10. The fastening interface 12 has, for example, fastening holes 13 allowing the bumper reinforcement 3 to be screwed or clipped onto the fastening interface 12.

[0026] Thus, during a frontal impact exceeding a predetermined threshold, particularly an impact against a pole of the enhanced pedestrian impact type, each foot 6 of the reinforcement 1 is shaped to break and release the lower part of the bumper reinforcement 3, while the recoil of the upper part of the reinforcement 3 is limited by the shock-absorbing elements 10. This makes it possible, for example, to limit injuries to a pedestrian's shins while limiting the recoil of the upper part of the reinforcement 3, which thus remains away from the motor-fan assembly. This improves the repairability of the vehicle according to the invention.

[0027] To facilitate the positioning and assembly of the reinforcement 3 on the frame 1, as illustrated in [Fig.3], each foot 6 has a U-shaped profile, the indexing means 9 having a fixing strap 14 at the end 7 of each foot 6. The indexing of the bumper reinforcement 3 on the frame 1 is achieved by complementary shape, allowing the bumper reinforcement 3 to fit into the U-shaped profile of the foot 6, and the indexing means 9 have bearing surfaces 15 provided on each foot 6, designed to form stops when the reinforcement 3 is assembled on the frame 1.

[0028] Advantageously, each fastening strap 14 is fusible so as to break under the effect of a frontal impact sustained by the front face 2 in order to release the reinforcement 3 of the bumper. shocks. Such a result is obtained, for example, by at least one thinning of material 16, visible on the [Fig.3], on each fastening strap 14.

[0029] Thus, the frame 1 according to the invention makes it possible to create a front face 2 according to the invention whose rigidity varies according to the height of the impact. In its lower part, the front face 2 allows for significant retraction of the bumper reinforcement 3 through the rupture of each foot 6, while in its upper part, each shock-absorbing element 10 limits the retraction of the reinforcement 3 towards the motor-fan assembly. The behavior of a vehicle according to the invention is therefore optimized for improved pedestrian impact protection.

[0030] The invention is not limited to the embodiment of the frame described above, only by way of example, but other embodiments can be designed by a person skilled in the art without departing from the scope and extent of the present invention.

Claims

Demands

1. Bumper support frame (1) for the front face (2) of a motor vehicle, designed to support, when fixed to the front face (2), a bumper reinforcement (3), the frame (1) having a transverse portion (4) designed to extend in a transverse direction (T) from the front face (2), the frame (1) having at least one foot (6) extending from the transverse portion (4) to an end (7) adapted to provide a fusible attachment of the bumper reinforcement (3) to the frame (1), the frame (1) having at least one energy-absorbing element (10) projecting from said transverse portion (4), each energy-absorbing element (10) being designed to absorb, when the frame (1) is mounted on the front face (2), a portion of the energy of a frontal impact experienced by the front face (2) by deforming in order to limit recoil in the front face (2), under the effect of the frontal impact, of at least part of the bumper reinforcement (3) fixed to the frame (1),characterized in that at least one absorber element (10) has a fastening interface (12) designed to allow the attachment of the bumper reinforcement (3) to the absorber element (10), each end (7) of each foot (6) has indexing means (9) designed to index and fix the reinforcement (3) relative to the frame (1), the indexing means (9) comprise a fastening strap (14), each fastening strap (14) is fusible so as to break under the effect of a frontal impact sustained by the front face (2) to release the bumper reinforcement (3).

2. Frame (1) according to claim 1, characterized in that each absorber element (10) forms an absorption box (11).

3. Frame (1) according to claim 2, characterized in that each box (11) has a frustoconical shape, in particular a frustoconical shape with a rectangular base.

4. Front face (2) of vehicle comprising a frame (1) according to any one of claims 1 to 3.

5. Vehicle comprising at least one front face (2) according to claim 4.

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