Front bumper arrangement for motor vehicle

Abstract

The invention relates to a front bumper arrangement (1) for a motor vehicle, the bumper arrangement (1) comprising two front side members (11), a front bumper cross member (12) extending between the two front side members (11), the front bumper cross member (12) being connected to the front end of each front side member (11) via a shock-absorbing system (13), two front supports (14) located at the front end of the front side members (11), shock-absorbing panels (15) located in an intermediate position between each front support (14) and the front bumper cross member (12), said shock-absorbing panels (15) extending close to the shock-absorbing system in order to be able to provide a bearing surface for the cross member (12) in the event of a frontal impact and total crushing of the shock-absorbing systems (13). Figure to be published with the abstract: Fig. 1

Description

Title of the invention: Front bumper arrangement for a motor vehicle

[0001] The technical context of the present invention is that of safety systems for motor vehicles, and in particular those used during low-speed front impacts. More particularly, the invention relates to a front bumper arrangement for a motor vehicle.

[0002] A motor vehicle comprises a powertrain housed in an engine compartment generally located in front of a passenger compartment of the motor vehicle, relative to a longitudinal axis. The powertrain makes it possible to generate engine torque on a running gear of the motor vehicle, in order to allow its forward propulsion in particular. The powertrain is generally supported by two front stretchers which are configured to, in addition to supporting said powertrain, protect occupants of the passenger compartment by preventing the intrusion of the powertrain into said passenger compartment following an accident.

[0003] The known front stretchers thus take the form of metal beams which extend mainly along the longitudinal axis of the motor vehicle, on either side of the powertrain.

[0004] In order to limit the damage caused by low-speed frontal impacts, the implementation, in front of the front side members, of a bumper arrangement comprising a cross member connected to the front side members via a shock-absorbing system is known. Such a shock-absorbing system is configured to be able to compress under the effect of a frontal impact, thus dissipating the energy of the frontal impact and preventing the front side members, the engine compartment or the passenger compartment from suffering too much damage. However, a known disadvantage of these front bumper arrangements lies in the fact that, in the event of a slightly higher frontal impact, the shock-absorbing system moves back and crashes against the front end of the front side member. This situation is not desired because the recoil of the shock-absorbing system against the front side member leads to damage to a front support located precisely at the level of the front end of the front side member.

[0005] The object of the present invention is to propose a new front bumper arrangement for a motor vehicle in order to address at least a large part of the preceding problems and to further lead to other advantages.

[0006] Another aim of the invention is to limit the deformations of the facade support in order to reduce repair costs and, consequently, the insurance class of the motor vehicle.

[0007] According to a first aspect of the invention, at least one of the aforementioned objectives is achieved with a front bumper arrangement for a motor vehicle, the bumper arrangement comprising:

[0008] - two front stretchers of main elongation along a longitudinal axis of the vehicle automobile, each front stretcher extending on either side of the longitudinal axis;

[0009] - a front bumper cross member extending between the two front side members along of a transverse axis of the motor vehicle, the front bumper crossmember being connected to the front end of each front stretcher by means of a shock absorption system;

[0010] - two facade supports extending mainly along a vertical axis of the vehicle at car, each front facade support being located at the level of the front end of the front stretchers.

[0011] According to the invention, the bumper arrangement according to the first aspect of the invention comprises shock absorbing panels located in an intermediate position between each front support and the front bumper crossmember.

[0012] In the context of the present invention, a longitudinal axis, a lateral axis and a vertical axis are defined relative to the motor vehicle on which the bumper arrangement according to the first aspect of the invention is intended to be mounted. More particularly, the transverse axis is understood as a direction taken between a lateral side of the motor vehicle and an opposite lateral side of said motor vehicle. In other words, the transverse axis is understood as a direction which extends from a passenger side of the motor vehicle to a driver's side of said motor vehicle, or vice versa. The adjectives lateral, inboard and outboard refer to such a transverse axis. Furthermore, the longitudinal axis extends as being taken along a direction which extends from front to rear or from back to front of the motor vehicle. The longitudinal axis is perpendicular to the transverse axis.The adjectives frontal, front and rear refer to this longitudinal axis. Finally, the vertical axis is understood to be taken along an axis that extends from the wheels of the motor vehicle and towards the roof of said motor vehicle, or vice versa, the vertical axis being simultaneously perpendicular to the transverse axis and to the longitudinal axis. The adjectives above and below, or lower and upper refer to this vertical axis.

[0013] In the context of the present invention, each front stretcher is a longitudinal structural part placed at the front of the motor vehicle and on which an engine unit of the motor vehicle is fixed. Each front stretcher extends from front to rear in the motor vehicle with which it is fitted, relative to the longitudinal axis. Each front stretcher is located under an engine compartment of the motor vehicle, at the front of the motor vehicle, behind a front bumper of the motor vehicle, and extends through the engine compartment and under a passenger compartment of the motor vehicle. Each front stretcher takes the form of a metal support fixedly attached to a chassis of the motor vehicle. In particular, at a front end of a passenger compartment of the motor vehicle, the front stretcher is fixedly attached to a base of the motor vehicle. In particular, the front stretcher is fixedly attached to a front bulkhead of the motor vehicle. At a rear end, the front stretcher is fixedly attached to a side member of the motor vehicle.

[0014] In the context of the present invention, the front bumper crossmember is a rectilinear or curved beam which extends mainly along the transverse axis. The crossmember is fixed integrally to the front ends of the front stretchers, by means of shock absorption systems. The crossmember thus forms an interface for transmitting forces, during a frontal impact towards the front stretchers and towards the chassis of the motor vehicle.

[0015] In the context of the present invention, each shock absorption system is interposed between the front bumper crossmember and the front ends of the front side members. The shock absorption system takes the form of longitudinal elongation bearing surfaces comprising a deformable section allowing, in the event of being subjected to a longitudinal axial force, to be crushed and compressed relative to the longitudinal axis, thus dissipating part of the energy of the frontal impact. At a front end, the shock absorption system is fixed integrally to the front bumper crossmember and, at a rear end, the shock absorption system is fixed integrally to the front end of the front side member located opposite.

[0016] In the context of the present invention, each front support forms a support and fixing surface for a grille or a front face of the motor vehicle. Each front support extends mainly along the vertical axis of the motor vehicle, so that the two front supports make it possible to define a fixing plane for the front face mainly oriented along the vertical axis and the transverse axis. Each front support is fixed integrally to a front end of the front stretcher with which it is associated. The front support extends above and / or below the front stretcher with which it is associated.

[0017] In the context of the present invention, the shock absorbing panel forms a dissipative element of the residual energy of the frontal impact, once the shock absorbing system is totally or almost totally compressed, in order to provide an additional safety margin for the associated front stretcher and front support. Relative to the longitudinal axis, each shock absorbing panel is located between the front stretcher and the front bumper crossmember, at the level of the front end of said front stretcher. The shock absorbing panel is configured to be crushed by the front bumper crossmember when the The shock absorption system is completely or almost completely compressed. In other words, in such a situation, the shock absorption panel is sandwiched between the front bumper crossmember and the front end of the front side member.

[0018] Thus, the front bumper arrangement according to the first aspect of the invention makes it possible to limit the deformations of the front support during a frontal impact, in the event of crushing of the shock absorption system. In other words, the shock absorption panel makes it possible to supplement the shock absorption system in order to replace it when the latter is completely compressed. Of course, the shock absorption panel is configured to absorb a certain amount of residual energy, persisting after the crushing of the shock absorption system. In the event of a very severe frontal impact, the front side rails and the front supports will be deformed or even damaged despite the shock absorption panel which will not have been able to absorb all the energy.On the other hand, for frontal impacts slightly greater than those that can be absorbed by the shock absorption system, then the shock absorption panel will take over effectively to protect both the front supports and the front stretcher. Consequently, the invention thus makes it possible to limit the occurrence of breakages or deterioration of the elements located at the front face, thus making it possible to reduce repair costs and the insurance class of the motor vehicle.

[0019] The front bumper arrangement according to the first aspect of the invention advantageously comprises at least one of the improvements below, the technical characteristics forming these improvements being able to be taken alone or in combination:

[0020] - the shock absorption panels comprise a first shock absorption panel impact associated with a first front support located on a first lateral side of the motor vehicle, and a second shock absorption panel associated with a second front support located on a second lateral side of the motor vehicle. Each shock absorption panel is associated with a front support and a front stretcher, in addition, each shock absorption panel is associated with a lateral end of the front bumper crossmember. This symmetrical configuration makes it possible to better distribute the forces between the two lateral sides of the front bumper on the one hand, and to allow optimal protection of each front stretcher and each front support in the event of a frontal impact offset to one lateral side or the other of the motor vehicle;

[0021] - each shock absorption panel is located opposite the bumper crossmember front. In other words, relative to the longitudinal axis of the motor vehicle, each impact absorption panel is located opposite a lateral end of the front bumper crossmember. In the nominal state, that is to say in the absence of a frontal impact, the impact absorption panel is located at a distance from the front bumper crossmember, relative to the longitudinal axis. Indeed, the objective here is that the panel shock absorption can serve as a support interface for the front bumper crossmember in the event of a frontal impact more violent than what the shock absorption system can absorb, so that in such circumstances, the front bumper crossmember moving back towards the front side member is pressed against the shock absorption panel rather than against the front support directly;

[0022] - each shock absorption panel is fixed securely to the facade support cor corresponding. This advantageous configuration makes it possible to maintain the shock absorption panel in position despite the use of the motor vehicle and the vibrations resulting from its rolling, for example. In particular, the front support comprises side edges and / or an upper edge and / or a lower edge making it possible to retain the shock absorption panel. Consequently, a general conformation of the shock absorption panel is similar to that of the front support taken between its edges, so that said shock absorption panel can be housed between them, preferably without play;

[0023] - as a non-limiting example, each shock absorption panel is glued on a face of the front support located opposite the front bumper crossmember, each shock absorption panel is associated with a front face of the corresponding front support, said front face being that which faces the front bumper crossmember, relative to the longitudinal axis, relative to the longitudinal axis;

[0024] - each shock absorbing panel extends in parallel with the absorption system corresponding impact. In other words, each impact absorption panel forms a device configured to absorb mechanical energy transmitted into the structure of the motor vehicle, from its front face and its front bumper, following a frontal impact, said impact absorption panel extending in parallel to the impact absorption system. These two devices are placed close to each other and so that they operate concomitantly, at least on the last degrees of compression of the impact absorption system, or that the impact absorption panel operates following the impact absorption system. By "operates", it is understood here that the impact absorption panel deforms and absorbs the energy of the frontal impact. This advantageous configuration thus makes it possible to better protect the corresponding front support;

[0025] - generally, each shock absorbing panel extends around the corresponding shock absorption system. More particularly, at the very least, each shock absorption panel extends on either side of the corresponding shock absorption system, relative to the transverse axis. Thus, according to an advantageous embodiment of the invention, each shock absorption panel has a general conformation in the shape of a “Y” or in the shape of a “U”. This advantageous configuration thus makes it possible to frame the shock absorption system shock between two side branches of the shock absorbing panel and forming its “Y” or “U” shape. In other words, a rear end of the shock absorbing system is located between the two side branches of the corresponding shock absorbing panel;

[0026] - each shock absorbing panel is formed of a material capable of deform for energies corresponding to those implemented during a frontal impact on the motor vehicle and for low speeds, for example less than 30 km / h. More particularly, the shock absorption panels are configured to deform and to absorb the mechanical energy induced by a frontal impact and for a speed of the motor vehicle between 15 km / h and 30 km / h. Each shock absorption panel comprises an expanded foam. By way of non-limiting example, each shock absorption panel is of the polypropylene foam type;

[0027] - a thickness of each shock absorption panel is greater than or equal to the thickness of the shock absorption system when it is fully compressed against the corresponding facade support, relative to the longitudinal axis. Typically, each shock absorption panel has a thickness of at least 15 mm.

[0028] According to a second aspect of the invention, there is provided a motor vehicle comprising a front bumper arrangement in accordance with the first aspect of the invention or according to any of its improvements.

[0029] Preferably, although not limiting of the present invention, the motor vehicle is of the type of an electrified motor vehicle. In the context of the present invention, an electrified motor vehicle may be of the type of an electric vehicle towed exclusively by an electric machine powered by an electric traction battery, or of the type of a hybrid motor vehicle comprising both the electric machine powered by the electric traction battery and associated with another propulsion system, such as a heat engine, to propel the motor vehicle.Among hybrid motor vehicles, a distinction is made between plug-in hybrid vehicles, for which the electric traction battery can be recharged by connecting it to an external energy source, and non-plug-in hybrid vehicles, i.e. vehicles which are not equipped for such recharging of the electric traction battery on an external electricity network.

[0030] Generally speaking, a powertrain of such an electrified motor vehicle is rotated by an electric machine, electrically powered by an electric traction battery, in order to generate a motor torque used to set the motor vehicle in motion. Additionally or alternatively, the electric machine is configured to recover mechanical energy from the powertrain and convert it into electrical energy, thus producing a braking torque. on said traction chain and allowing the electric traction battery to be recharged.

[0031] Various embodiments of the invention are provided, integrating, according to all of their possible combinations, the various optional characteristics set out here.

[0032] Other characteristics and advantages of the invention will become apparent from the following description on the one hand, and from several exemplary embodiments given for informational and non-limiting purposes with reference to the attached schematic drawings on the other hand, in which:

[0033] [Fig-1] illustrates a three-dimensional front view of an exemplary embodiment of the arrangement according to the first aspect of the invention, in its normal state of use;

[0034] [Fig.2] illustrates a side view of the arrangement illustrated in [Fig.l] and consequent tively to a frontal collision;

[0035] [Fig.3] illustrates a three-dimensional view of a front face of a motor vehicle in incorporating such an arrangement, shown in its state following a head-on collision.

[0036] Of course, the features, variants and different embodiments of the invention may be combined with each other, in various combinations, provided that they are not incompatible or mutually exclusive. In particular, variants of the invention may be imagined comprising only a selection of features described below in isolation from the other features described, if this selection of features is sufficient to confer a technical advantage or to differentiate the invention from the prior art.

[0037] In particular, all the variants and all the embodiments described can be combined with each other if nothing prevents this combination from a technical point of view.

[0038] In the figures, the elements common to several figures retain the same reference.

[0039] In the FIGURES described below, a longitudinal axis, a lateral axis and a vertical axis are defined relative to the motor vehicle on which the bumper arrangement 1 is intended to be mounted.

[0040] More particularly, the transverse axis is understood as a direction taken between a lateral side of the motor vehicle and an opposite lateral side of said motor vehicle. In other words, the transverse axis is understood in a direction which extends from a passenger side of the motor vehicle to a driver's side of said motor vehicle, or vice versa. The adjectives lateral, interior and exterior refer to such a transverse axis.

[0041] Further, the longitudinal axis extends as taken along a direction that extends from front to rear or from back to front of the motor vehicle. The longitudinal axis gitudinal is perpendicular to the transverse axis. The adjectives frontal, front, and rear refer to this longitudinal axis.

[0042] Finally, the vertical axis is understood to be taken along an axis which extends from the wheels of the motor vehicle and towards the roof of said motor vehicle, or vice versa, the vertical axis being simultaneously perpendicular to the transverse axis and to the longitudinal axis. The adjectives above and below, or lower and upper refer to this vertical axis.

[0043] With reference to FIGURES 1 to 3, the invention relates to a front bumper arrangement 1 for a motor vehicle, the bumper arrangement 1 comprising:

[0044] - two front stretchers 11 of main elongation along the longitudinal axis, each front stretcher 11 extending on either side of the longitudinal axis;

[0045] - a cross member 12 of the front bumper extending between the two front side members 11 along the transverse axis, the front bumper cross member 12 being connected to the front end of each front stretcher 11 by means of a shock absorption system 13;

[0046] - two facade supports 14 extending mainly along the vertical axis, each support front 14 being located at the level of the front end of the front stretchers 11;

[0047] - shock absorbing panels 15 located in an intermediate position between each facade support 14 and the front bumper cross member 12.

[0048] Of course, FIGURES 1 and 3 only describe a lateral part of the motor vehicle and the arrangement 1 associated with it. Also, in FIGURES 1 to 3, only one of the two front stretchers 11 is visible, associated with its front support 14 and its shock absorption panel 15. The arrangement 1 according to the invention is advantageously symmetrical with respect to a sagittal median plane of the motor vehicle.

[0049] As visible in the FIGURES, the invention aims to insert the shock absorption panels 15 in an intermediate and intermediate position between the cross member 12 of the front bumper and the front supports 14 installed at a front end of the front stretchers 11. Each shock absorption panel 15 is associated with one of the front stretchers 11. Each shock absorption panel 15 is associated with one of the shock absorption systems 13 connecting the cross member 12 of the front bumper to the front stretchers 11.

[0050] For this purpose, each shock absorption panel 15 takes the form of an insert mounted on a front face of the corresponding facade support 14. More particularly, each shock absorption panel 15 takes the form of a plate formed from an absorbent material - for the energies in question in the automotive field - such as for example an expanded polypropylene foam.

[0051] The shape and dimensions of each shock absorption panel 15 are adjusted to the dimensions of the facade support 14 against which said shock absorption panel 15 is backed. In particular, as visible in [Fig.l], each shock absorption panel 15 is housed between lateral edges 141, 142 141 of the facade support 14 and held vertically by a lower edge 142 of said facade support 14.

[0052] During their assembly, the shock absorption panels 15 are slid vertically along the vertical axis along the facade support 14, from below and upwards, towards the shock absorption system 13. For this purpose, the lower edge 142 is cleverly mounted pivoting or removable.

[0053] Each shock absorption panel 15 has a general “U” or “Y” shape. Generally, each shock absorption panel 15 comprises two lateral branches 152 spaced apart from each other, relative to the transverse axis, so as to allow the insertion between them of the shock absorption systems 13. This clever configuration thus makes it possible to activate the shock absorption panel 15 when the shock absorption system 13 is completely crushed, as illustrated in [Fig.2] and [Fig.3].

[0054] For this purpose, a thickness of the shock absorption panels 15 is such that a front face of said shock absorption panels 15 is located in front of the shock absorption system 13 when the latter is completely crushed against the facade support 14. In this way, rather than deforming the facade support 14, the crosspiece 12 will then be placed in abutment against the shock absorption panel 15, thus protecting the facade support 14.

[0055] Each shock absorption panel 15 is preferably held against the corresponding front support 14 so that it does not fall during the rolling phases of the motor vehicle. By way of non-limiting example, the shock absorption panel 15 is glued to the corresponding front support 14.

[0056] The shock absorption panel 15 comprises a lower portion 151 which extends below the shock absorption system 13 and from which lower portion 151 the two lateral branches 152 project. This advantageous configuration makes it possible to guarantee good stability and robustness to the shock absorption panel 15.

[0057] In summary, the invention relates to a front bumper arrangement 1 for a motor vehicle, the bumper arrangement 1 comprising two front side members 11, a front bumper cross member 12 extending between the two front side members 11, the front bumper cross member 12 being connected to the front end of each front side member 11 via a shock absorption system 13, two front supports 14 located at the front end of the front side members 11, shock absorption panels 15 located in an intermediate position between each front support 14 and the front bumper cross member 12, said shock absorption panels 15 extending close to the shock absorption system in order to be able to offer a support surface for the cross member 12 in the event of a frontal impact and total crushing of the shock absorption systems 13.

[0058] Of course, the invention is not limited to the examples which have just been described and numerous adjustments can be made to these examples without departing from the scope of the invention. In particular, the different characteristics, forms, variants and embodiments of the invention can be associated with each other in various combinations insofar as they are not incompatible or mutually exclusive. In particular, all the variants and embodiments described above can be combined with each other.

Claims

Claims

1. Front bumper arrangement (1) for a motor vehicle, the bumper arrangement (1) comprising: - two front side members (11) of main elongation along a longitudinal axis of the motor vehicle, each front side member (11) extending on either side of the longitudinal axis; - a cross member (12) of the front bumper extending between the two front side members (11) along a transverse axis of the motor vehicle, the front bumper cross member (12) being connected to the front end of each front side member (11) via a shock absorption system (13); - two front supports (14) extending mainly along a vertical axis of the motor vehicle, each front front support (14) being located at the front end of the front side members (11);characterized in that the bumper arrangement (1) comprises shock absorbing panels (15) located in an intermediate position between each front support (14) and the front bumper crossmember (12).;

2. Front bumper arrangement (1) according to the preceding claim, wherein each shock absorbing panel (15) is located opposite the front bumper cross member (12).

3. Front bumper arrangement (1) according to any one of the preceding claims, wherein each shock absorbing panel (15) is fixed integrally to the corresponding front support (14).

4. A front bumper arrangement (1) according to any preceding claim, wherein each shock absorbing panel (15) extends in parallel with the corresponding shock absorbing system.

5. A front bumper arrangement (1) according to any preceding claim, wherein each shock absorbing panel (15) extends on either side of the corresponding shock absorbing system, relative to the transverse axis.

6. A front bumper arrangement (1) according to any preceding claim, wherein each shock absorbing panel (15) has a general "Y" or "U" shaped conformation.

7. Front bumper arrangement (1) according to any one of the claims- preceding indications, wherein each shock absorbing panel (15) comprises an expanded foam.

8. Front bumper arrangement (1) according to any one of the preceding claims, wherein a thickness of each shock absorbing panel (15) is greater than or equal to the thickness of the shock absorbing system when the latter is fully compressed against the corresponding front support (14), relative to the longitudinal axis.

9. A motor vehicle comprising a front bumper arrangement (1) according to any one of the preceding claims.

Images