Motor vehicle shock absorption device

Abstract

Motor vehicle shock absorption device The shock absorption device (10) is intended to be attached in front of a transverse beam (8) of the vehicle (5). It comprises a first rigid cross member (14), intended to be arranged in contact with said transverse beam (8), and a second cross member (16) of lower rigidity than that of the first cross member (14), comprising a first part (16a) arranged in front of the first cross member (14), and a second part (16b) extending above the first cross member (14). Figure for abstract: Figure 1

Description

Title of the invention: Vehicle shock absorption device for automobiles

[0001] The present invention relates to a shock absorption device, intended to equip a motor vehicle.

[0002] A motor vehicle bumper usually comprises an external decorative casing, called a skin, and a device for absorbing the energy of an impact, intended to consume the energy of an impact by deforming in order to transmit as little as possible to the vehicle.

[0003] Different types of impacts are considered when developing a shock-absorbing device, namely high-speed impacts which correspond to a frontal impact of the vehicle against a rigid or deformable obstacle at a speed of 56 to 64 km / h, "insurance" impacts such as that known as "Danner", at 15 km / h against a fixed wall, and small impacts, or "parking" impacts at a speed of between 4 and 8 km / h. High-speed impacts are considered with the objective of protecting the vehicle occupants, while "insurance" and "parking" impacts, i.e. "small impacts", correspond rather to an objective of reducing repair costs. It is also necessary to consider pedestrian impacts, which respect the pedestrian's leg in order to limit serious and disabling injuries.

[0004] The present invention relates more particularly to a shock absorption device intended for the treatment of small impacts and pedestrian impacts.

[0005] The shock absorption device is conventionally intended to be attached in front of a transverse beam of the vehicle.

[0006] Such a motor vehicle also usually includes a grille, also in front of the transverse beam. More particularly, in the context of a grille comprising lighting parts, it is desirable that this grille does not come into contact with the transverse beam during a small impact (in particular a parking lot or pedestrian impact), in order to safeguard these lighting parts.

[0007] Thus, the invention aims in particular to propose a shock absorption device capable of protecting the grille in the event of a small impact.

[0008] To this end, the invention relates in particular to a shock absorption device for a motor vehicle, intended to be attached in front of a transverse beam of the vehicle, characterized in that it comprises:

[0009] - a first rigid crosspiece, intended to be arranged in contact with said beam transverse, and

[0010] - a second crosspiece of lower rigidity than that of the first crosspiece, comprising a first portion arranged in front of the first crossmember, and a second portion extending above the first crossmember.

[0011] The invention makes it possible to decouple the “pedestrian” and “small impacts” functions. The first rigid crossmember acts as a spacer and makes it possible to limit the intrusion of parking impact buffers (ECE42 type and equivalents). The sinking of the grille is thus limited, so that the grille does not come into contact with the front beam in the event of a small impact or pedestrian impact.

[0012] The second, flexible crosspiece allows the pedestrian leg impact function to be managed, and at the same time, it allows the repeatability of parking impact to be guaranteed.

[0013] An absorption device according to the invention may also have one or more of the following characteristics, taken alone or in any technically conceivable combination:

[0014] - The first crosspiece is made of injected polyethylene.

[0015] - The second crosspiece is made of expanded polypropylene.

[0016] - The second crosspiece is overmolded onto the first crosspiece.

[0017] - The second crosspiece is fixed to the first crosspiece, for example by snap-fastening.

[0018] - The second cross member comprises means for fixing to a bumper of the vehicle, for example, snap-on means.

[0019] - The absorption device comprises means for fixing the first crosspiece on the vehicle beam.

[0020] The invention also relates to a motor vehicle, comprising a front transverse beam, characterized in that it comprises an absorption device as defined previously, arranged in front of said transverse beam.

[0021] Preferably, the motor vehicle comprises a grille arranged in front of the beam, the first and second cross members being configured so that, when the first portion of the second cross member is compressed, the grille remains clear of the beam.

[0022] Various aspects and advantages of the invention will be highlighted in the following description, given solely by way of non-limiting example, and made with reference to the drawings in which:

[0023] [Fig.l] [Fig.l] is a schematic sectional view of an absorption device according to an exemplary embodiment of the invention;

[0024] [Fig.2] [Fig.2] is a view similar to [Fig.l] of the shock absorption device.

[0025] The figures show a front area of ​​a motor vehicle 5. In the present description, the term “front” is to be considered with respect to a conventional orientation of the motor vehicle 5, in a longitudinal direction X of the vehicle.

[0026] The motor vehicle 5 comprises a bumper 6, comprising a bumper skin conventional shock absorbers 7, a conventional front transverse beam 8, and an absorption device 10 according to an exemplary embodiment of the invention.

[0027] The motor vehicle 5 also carries a grille 12. The grille 12 is arranged in front of the transverse beam 8 in the longitudinal direction X. At least a portion of the grille 12 is located at the height of at least a portion of the beam 8 in a vertical direction Z.

[0028] The grille 12 is for example of the self-illuminated type, and therefore carries lighting parts.

[0029] The absorption device 10 comprises a first rigid crosspiece 14, intended to be arranged in contact with said transverse beam 8. Preferably, the absorption device 10 comprises means for fixing the first crosspiece 14 to the transverse beam 8.

[0030] The first crosspiece 14 has sufficient rigidity to remain non-deformable in the event of a small impact, i.e. an impact of less than 8 km / h. For example, the first crosspiece 14 has a Young's modulus greater than 2000 MPa.

[0031] The first crosspiece 14 is for example made of injected polyethylene. The polyethylene may be, in one variant, loaded with talc, or in another variant, devoid of talc.

[0032] The absorption device 10 comprises a second crosspiece 16 of lower rigidity than that of the first crosspiece 14 (therefore having a Young's modulus lower than that of the first crosspiece 14). For example, the second crosspiece 16 has a Young's modulus lower than 1000 MPa.

[0033] For example, the second crosspiece 16 is made of expanded polypropylene. Preferably, the weight of the second crosspiece 16 is between 30g / l and 60g / l.

[0034] The second crosspiece 16 comprises a first part 16a arranged in front of the first crosspiece 14 (i.e. aligned in the longitudinal direction X), and a second part 16b extending above the first crosspiece 14 (in the vertical direction Z).

[0035] According to a first variant embodiment, the second crosspiece 16 is overmolded onto the first crosspiece 14.

[0036] According to a second variant embodiment, the second crosspiece 16 is fixed to the first crosspiece 14, for example by snap-fastening.

[0037] Preferably, the second crosspiece 16 comprises means for fixing to the bumper 6 of the vehicle 5, for example snap-fastening means.

[0038] The first 14 and second 16 crosspieces are configured so that, when the first portion 16a of the second crosspiece 16 is compressed, the calender 12 remains clear of the beam 8, as shown in [Fig. 2]. For this purpose, the sum of the dimension, in the longitudinal direction X, of the first crosspiece 14 and the dimension, in the longitudinal direction X, of the first crushed part 16a, is greater than the dimension of the calender 12 in the longitudinal direction X.

Claims

Claims

1. Device (10) for absorbing shocks from a motor vehicle (5), intended to be attached in front of a transverse beam (8) of the vehicle (5), characterized in that it comprises: - a first rigid cross member (14), intended to be arranged in contact with said transverse beam (8), and - a second cross member (16) of lower rigidity than that of the first cross member (14), comprising a first part (16a) arranged in front of the first cross member (14), and a second part (16b) extending above the first cross member (14).

2. Absorption device (10) according to claim 1, in which the first crosspiece (14) is made of injected polyethylene.

3. An absorption device (10) according to claim 1 or 2, wherein the second crosspiece (16) is made of expanded polypropylene.

4. An absorption device (10) according to any one of claims 1 to 3, wherein the second crosspiece (16) is overmolded onto the first crosspiece (14).

5. An absorption device (10) according to any one of claims 1 to 3, wherein the second crosspiece (16) is attached to the first crosspiece (14), for example by snap-fastening.

6. Absorbing device (10) according to any one of the preceding claims, in which the second cross member (16) comprises means for fixing to a bumper (6) of the vehicle, for example snap-fastening means.

7. Absorption device (10) according to any one of the preceding claims, comprising means for fixing the first cross member (14) to the beam (8) of the vehicle.

8. Motor vehicle (5), comprising a front transverse beam (8), characterized in that it comprises an absorption device (10) according to any one of the preceding claims, arranged in front of said transverse beam (8).

9. A motor vehicle according to claim 8, comprising a grille (12) arranged in front of the beam (8), the first (14) and second (16) cross members being configured so that, when the first portion (16a) of the second cross member (16) is compressed, the grille (12) remains clear of the beam (8).

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