Reinforced shock absorption device in traction.

Abstract

The invention relates to a shock-absorbing device (1) for a front end of a motor vehicle, comprising a bumper beam (2), at least one fixing plate (3), designed to allow the device (1) to be fixed to the front end, and at least one shock absorber (6), designed to be crushed in the event of a front impact suffered by the front end equipped with the device (1), each absorber (6) extending between a first end (11), secured to a plate (3), and a second end (12), secured to the beam (2), the device (1) comprising at least one reinforcing element (13) secured to a plate (3) and to the beam (2), each reinforcing element (13) being shaped to transmit to the plate (3) a tensile force exerted on the beam (2) and to allow the beam (2) and the plate (3) to be brought together in the event of crushing of an absorber (6). (Figure 1)

Description

Title of the invention: Shock absorption device reinforced in traction.

[0001] The technical field concerns shock absorption devices, vehicle front ends equipped with such an absorption device, as well as motor vehicles.

[0002] In terms of road safety, automobile manufacturers must take into account multiple concerns and regulations when developing new vehicles. Thus, automobile manufacturers must ensure the safety of vehicle passengers in the event of a collision but also protect other more vulnerable road users such as pedestrians. Finally, it is necessary to seek to control the repair costs of vehicles when they undergo urban impacts, called reparability impacts, i.e. impacts suffered at low speeds of the order of 15 to 20 kilometers per hour. The behavior of motor vehicles in these three situations is regulated and tested by implementing standardized test procedures. The requirements in terms of results in these tests are increasingly numerous and more difficult to satisfy and force automobile manufacturers to constantly innovate.

[0003] To meet the requirements mentioned above, motor vehicle manufacturers have thus developed shock absorption systems, which, as a general rule, comprise a bumper beam connected to the chassis of the vehicle by means of absorption boxes arranged between the bumper beam and a side member and designed to deform during an impact, typically by undergoing compression so as to allow the bumper beam to move towards the side members. Usually, the bumper beam and the absorption boxes are made of steel or aluminum. Automobile manufacturers are very good at modeling the deformations of these metal shock absorption systems.

[0004] These shock absorption systems prove to be very effective in absorbing part of the energy released during a front impact suffered by the vehicle equipped with such a system. However, the beam is generally provided with means for fixing a towing socket to tow the vehicle if necessary. These means are used in particular to secure the vehicle for maritime transport. However, during such transport, the vehicle and the absorption system are subjected to numerous movements, linked for example to swell. These movements generate stress cycles, in particular in traction, which are likely to weaken the absorption system by causing fatigue cracks in the system. absorption. Such fatigue is obviously unacceptable. In order to strengthen the absorption system to avoid fatigue during docking, it is possible to increase the thickness of the various elements of the system and in particular the absorption boxes. However, such a solution, in addition to being costly to implement, is not suitable in a context where manufacturers are seeking to reduce the mass of their vehicles.

[0005] Thus, there is a need for a solution making it possible to reinforce a shock absorption system in a maritime lashing situation without degrading the behavior of the absorption system in the event of a front impact and without excessively increasing the mass.

[0006] The present invention aims to overcome the problems set out above. In this technical context, one aim of the present invention is to provide a shock absorption device having characteristics suitable for front impact, but reinforced in order to have increased resistance during traction cycles exerted on the beam and representative of maritime transport.

[0007] For this purpose, the present invention relates to a shock absorption device for a front end of a motor vehicle, comprising a bumper beam, at least one fixing plate, designed to allow the device to be fixed to the front end, and at least one shock absorber, designed to be crushed in the event of a front impact suffered by the front end equipped with the device, each absorber extending between a first end, secured to a fixing plate, and a second end, secured to the bumper beam, the device further comprising at least one reinforcing element secured, on the one hand, to a plate and, on the other hand, to the bumper beam, each reinforcing element being shaped to transmit to the plate a tensile force exerted on the beam and to allow the beam and the plate to be brought together in the event of an absorber being crushed under the effect of a front impact.

[0008] The invention also relates to a front face of a motor vehicle comprising an absorption device according to the invention, each plate being fixed to a structural element of the front face, in particular a side member.

[0009] The invention finally relates to a motor vehicle having a front face according to the invention.

[0010] Thus, the absorption device according to the invention has all the characteristics required to absorb a front impact suffered by the vehicle equipped with a front end according to the invention. In particular, each absorber is capable of undergoing crushing to absorb all or part of the energy released during the front impact. Each reinforcing element, connecting a plate to the beam, makes it possible to transfer at least part of the tensile forces, usually suffered by the beam during lashing, to the plate. This distribution of forces thus makes it possible to reduce in particular the risks of fatigue of the beam fixings with the absorbers. The conformation of the reinforcing element, by allowing the crushing of an absorber, does not modify or only slightly the behavior of the device in the event of a front impact. The solution provided by the device according to the invention and its reinforcing element has the advantage of not making the device heavier, unlike a solution involving increased thicknesses.

[0011] According to one embodiment of the invention, each reinforcing element extends opposite a face of an absorber and in a direction inclined relative to the face of the absorber. Thus, the deformation of a reinforcing element in the event of a front impact is facilitated.

[0012] According to one possibility, each reinforcing element is fixed at the right of the first and second ends of the same shock absorber.

[0013] In one embodiment of the absorption device, each reinforcing element forms a blade, in particular a metal blade made of steel.

[0014] Advantageously, the blade has a rectangular cross-section.

[0015] According to one possibility, each reinforcing element is fixed to the beam at a fixing hole, provided in the beam and allowing the fixing of a towing socket to the beam.

[0016] According to one embodiment of the absorption device, each reinforcing element is welded to the plate and / or to the beam.

[0017] The invention will be better understood on reading the detailed description which follows, given solely by way of non-limiting example and made with reference to the appended drawing in which:

[0018] [Fig-1] [Fig.l] represents a partial perspective view of a device shock absorption according to the invention.

[0019] A shock absorption device 1 according to the invention, illustrated in [Fig.l], is intended to equip a front face of a motor vehicle according to the invention, not illustrated.

[0020] The device 1 comprises a bumper beam 2 designed to extend across the front face. Conventionally, the beam 2 forms a metal profile. The device 1 is fixed to the front face using at least one fixing plate 3. Each plate 3 forms a plate 4 provided with fixing holes 5 to allow the device 1 to be fixed to a structural element, not shown, such as for example a side member.

[0021] The device 1 further comprises at least one shock absorber 6, in this case two shock absorbers 6 each arranged on either side of the beam 2. Each absorber 6 is designed to crush under the effect of a front impact suffered by the front face equipped with the device 1. For this purpose, each absorber 6 has a parallel body 7 piped formed for example from a sheet metal 8. The body 7 has at least one compression incipient 9, each designed to facilitate the crushing of the absorber 6, produced, for example, in the form of a cutout in an edge 10 of the body 7. Each absorber 6 extends between a first end 11, secured to a fixing plate 3, and a second end 12, secured to the bumper beam 2.

[0022] As illustrated in the figure, the device 1 according to the invention further comprises at least one reinforcing element 13 secured, on the one hand, to a plate 3 and, on the other hand, to the bumper beam 2. Each reinforcing element 13 is shaped to transmit to the plate 3 a tensile force exerted on the beam 2 and to allow the beam 2 and the plate 3 to be brought together in the event of crushing of an absorber 6 under the effect of a front impact. In the example illustrated in the figure, each reinforcing element 13 extends opposite a face 14 of an absorber 6 and in a direction inclined relative to the face 14 of the absorber 6. As illustrated in the figure, each reinforcing element 13 is fixed at right angles to the first 11 and second 12 ends of the same shock absorber 6. In the example illustrated in the figure, each reinforcing element 13 forms a blade 15, in particular a metal blade made of steel.The blade 15 advantageously has a rectangular cross-section. In the device 1 described, the blade 15 is arranged so that its thickness extends in a plane substantially perpendicular to the face 14 of the absorber 6, opposite which the blade 15 extends. The dimensions of the blade 15, in particular its thickness, are chosen so as to resist a tensile force exerted on the beam 2 but allowing the blade 15 to bend in the event of crushing of an absorber 6. For example, the thickness of the blade 15 is 2.5 mm for a blade 15 made of steel.

[0023] Advantageously, each reinforcing element 13 is fixed to the beam 2 at right angles to a fixing orifice 16, provided in the beam 2 and allowing the fixing of a towing socket, not illustrated, to the beam 2.

[0024] For example, the fixing of each reinforcing element 13 is obtained by welding to the plate 3 and / or the beam 2.

[0025] Thus, the absorption device 1 according to the invention has all the characteristics required to absorb a front impact suffered by the vehicle equipped with a front end according to the invention. In particular, each absorber 6 is capable of undergoing crushing to absorb all or part of the energy released during the front impact. Each reinforcing element 13, connecting a plate 3 to the beam 2, makes it possible to transfer at least part of the tensile forces, usually suffered by the beam 2 during lashing, to the plate 3. This distribution of forces thus makes it possible to reduce in particular the risks of fatigue of the fixings of the beam 2 on the absorbers 6. The conformation of the reinforcing element 13, by allowing the crushing of a absorber 6, does not modify or only slightly modifies the behavior of device 1 in the event of a front impact.

[0026] The invention is not limited to the embodiment of the shock absorption device described above, only by way of example, but other embodiments can be designed by those skilled in the art without departing from the scope and scope of the present invention.

Claims

Claims

1. Shock absorbing device (1) for a front end of a motor vehicle, comprising a bumper beam (2), at least one fixing plate (3), designed to allow the device (1) to be fixed to the front end, and at least one shock absorber (6), designed to crush in the event of a front impact suffered by the front end equipped with the device (1), each absorber (6) extending between a first end (11), secured to a fixing plate (3), and a second end (12), secured to the bumper beam (2), the device (1) further comprising at least one reinforcing element (13) secured, on the one hand, to a plate (3) and, on the other hand, to the bumper beam (2),each reinforcing element (13) being shaped to transmit to the plate (3) a tensile force exerted on the beam (2) and to allow the beam (2) and the plate (3) to come together in the event of crushing of an absorber (6) under the effect of a front impact.,

2. Absorption device (1) according to claim 1, characterized in that each reinforcing element (13) extends opposite a face (14) of an absorber (6) and in a direction inclined relative to the face (14) of the absorber (6).

3. Absorption device (1) according to claim 1 or 2, characterized in that each reinforcing element (13) is fixed at the right of the first (11) and second (12) ends of the same shock absorber (6).

4. Absorption device (1) according to one of claims 1 to 3, characterized in that each reinforcing element (13) forms a blade (15), in particular a metal blade (15) made of steel.

5. Absorption device (1) according to claim 4, characterized in that the blade (15) has a rectangular cross-section.

6. Absorption device (1) according to one of claims 1 to 5, characterized in that each reinforcing element (13) is fixed to the beam (2) at right angles to a fixing orifice (16), provided in the beam (2) and allowing the fixing of a towing socket to the beam (2).

7. Absorption device (1) according to one of claims 1 to 6, characterized in that each reinforcing element (13) is welded to the plate (3) and / or to the beam (2).

8. Front end of a motor vehicle comprising a device (1)

9. absorption according to one of claims 1 to 7, each plate (3) being fixed to a structural element of the front face, in particular a side member. Motor vehicle having a front end according to claim 8.

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