Air deflector for motor vehicle

Abstract

The invention relates to an aerodynamic deflector (1) for a motor vehicle, the aerodynamic deflector (1) being intended to be fixed rigidly to a lower cross member located behind the front bumper, the aerodynamic deflector (1) comprising: - a main body (11) which extends under the bumper of the motor vehicle; - a member (12) for absorbing mechanical energy resulting from a front impact against the aerodynamic deflector (1), the absorbing member (12) extending in projection from a front edge (111) of the main body (11) of the aerodynamic deflector (1), relative to a longitudinal axis (X); - a plurality of energy absorption cells (121), spaced apart along a transverse axis (Y), so that the absorption element (12) of the aerodynamic deflector (1) has a comb-shaped geometry, each cell (121) forming a hollow box that can be compressed and / or deformed in the event of a frontal collision with a pedestrian.The dimensions and / or thickness of each cell (121), as well as the material used, are designed to allow deformation upon impact with a pedestrian. The stiffness of each cell (121) is therefore determined for such operating conditions. Figure to be published with the abbreviation: Fig. 1.

Description

Title of the invention: Air deflector for a motor vehicle

[0001] The technical context of the present invention is that of structural elements for motor vehicles, and in particular those located under their chassis. More particularly, the invention relates to an air deflector for a motor vehicle.

[0002] In the state of the art, motor vehicle chassis are known to which front or rear bumpers are fixed. Such bumpers are mounted on the chassis by means of a bumper support which makes it possible to position and provide a mounting interface between such bumpers and the corresponding bumper support. For this purpose, the bumper support comprises fixing lugs which are used to securely fix the bumper. To complete such an underbody assembly, and to optimize air flow under the motor vehicle, the use of an air deflector placed in the extension of a part of the bumper located under the chassis, beyond the aforementioned fixing lugs is known.

[0003] Such an air deflector thus generally forms a plate of variable shape which extends laterally between the wheels of the motor vehicle, and in the direction of the bumper. Such an air deflector extends longitudinally under the motor vehicle, in the direction of a passenger compartment of the motor vehicle. The air deflector is fixed integrally to the bumper support and / or to the bumper directly.

[0004] In the context of tests aimed at determining the most dangerous points for pedestrians' legs during a frontal impact with a motor vehicle, in particular at a speed of 40 km / h, it is known that the bumper is the component which most often comes into contact first with the pedestrian in the event of an impact, and mainly with the latter's legs.

[0005] We thus know the use of a lower deflector, located below a front bumper, resting on a lower beam of the bumper, and making it possible to deflect the lower leg of a pedestrian, in the event of impact with the latter. To facilitate the passage of air above the lower beam and to comply with the ground clearance constraints of the motor vehicle, a section of the lower deflector is very often trapezoidal, the smaller side of the lower deflector being located towards the front of the motor vehicle.

[0006] A disadvantage of known deflectors lies in their geometry: they have a uniform and continuous geometry from one side edge of the motor vehicle to the other. This geometry is not very effective in dissipating the mechanical energy resulting from the impact. In other words, all the mechanical energy not dissipated by the lower deflector is returned to the leg of the impacted pedestrian, leading to potentially significant damage to the pedestrian.

[0007] The object of the present invention is to propose a new air deflector in order to respond at least to a large extent to the preceding problems and to further lead to other advantages.

[0008] Another object of the invention is to reduce the damage caused to the leg of a pedestrian impacted during a frontal collision.

[0009] Another aim of the invention is to allow better dissipation of the mechanical energy resulting from the shock at the level of the air deflector.

[0010] According to a first aspect of the invention, at least one of the aforementioned objectives is achieved with an air deflector for a motor vehicle, the air deflector being intended to be fixed securely to a lower cross member located behind the front bumper, the air deflector comprising:

[0011] - a main body which extends under the bumper of the motor vehicle;

[0012] - a member for absorbing mechanical energy resulting from a front impact against the air deflector, the absorption member extending projecting from a front edge of the main body of the air deflector, relative to a longitudinal axis.

[0013] According to the invention, the absorption member comprises a plurality of energy absorption cells, spaced apart from each other along a transverse axis, so that the absorption member of the air deflector has a comb-shaped geometry.

[0014] 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 air deflector 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, interior and exterior 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 rear 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 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.

[0015] In the context of the present invention, the main body of the air deflector according to the first aspect extends mainly along the transverse axis, between the wheels of the motor vehicle, and along the longitudinal axis, from a front face of the motor vehicle and towards the passenger compartment. Thus the air deflector according to the invention mainly forms a plate - or a structure of lesser height, intended to be arranged under the front bumper.

[0016] In the context of the present invention, the absorption member is configured to absorb mechanical energy during a frontal impact, so as to prevent said mechanical energy from the impact from being transmitted to the impacted pedestrian or to the various elements of the motor vehicle located behind the bumper. The absorption member therefore forms a deformable member along the longitudinal axis in order to allow such absorption.

[0017] In the context of the present invention, the energy absorption cells form deformable boxes, independently of each other. The absorption cells are located at the front edge of the air deflector. The cells thus form three-dimensional modules which are configured to be able to deform under the effect of a frontal impact, typically by compression along the longitudinal axis, in order to absorb said frontal impact.

[0018] In the context of the present invention, the comb-shaped geometry of the absorption member results from the geometry and positioning of the different absorption cells. Each absorption cell has a front surface edge so as to increase the contact surface and facilitate the activation of a deformation mode of said cell. Thus, each cell extends from the front edge of the air deflector and along the longitudinal axis. Furthermore, each cell is distant from the adjacent cell, relative to the transverse axis. Consequently, the comb-shaped geometry of the air deflector according to the invention results from this advantageous configuration which forms recessions and protrusions, alternately distributed along the front edge of the air deflector.

[0019] Thus, the air deflector according to the first aspect of the invention makes it possible to reduce injuries inflicted on a pedestrian in the event of a frontal impact, because the absorption cells offer a better response during such an impact. They each make it possible to dissipate mechanical energy and reduce the energy returned to the impacted leg.

[0020] The air deflector 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:

[0021] - the cells are all equidistant from each other. In particular, a distance between two adjacent cells is between 40mm and 90mm, preferably equal to 65mm;

[0022] - the absorption organ has an odd number of cells. Complement tarily, the absorption member is symmetrical with respect to a median longitudinal axis of the air deflector. This advantageous configuration makes it possible to propose a geometry according to which, at a median longitudinal axis of the motor vehicle, there is no cell, so that if the leg of a pedestrian is impacted here, it will be opposite two adjacent cells, thus improving energy dissipation. In the context of the present invention, the median longitudinal axis of the air deflector is located between two adjacent cells;

[0023] - the cells all have identical dimensions and / or shapes. More gene Generally, at least some of the cells forming the absorption organ have identical dimensions and / or shapes. Generally, the cells form hollow boxes so as to make them more easily deformable and to provide a volume reserve for their compression and, ultimately, for the dissipation of mechanical energy;

[0024] - each cell has a protrusion which extends along the longitudinal axis from the front edge of the main body, the protrusion delimiting a non-zero interior volume. More generally, at least part of the cells forming the absorption organ comprises a protrusion delimiting a non-zero interior volume;

[0025] - according to a first variant embodiment, the protrusion forming at least one part of the cells has a parallelepiped shape. According to a second embodiment, the protrusion forming at least part of the cells has a pyramidal shape, a front part of the protrusion being of lesser thickness than a rear part of the protrusion, the thickness being taken along a vertical axis;

[0026] - the protrusion forming at least part of the cells has a width between 40 mm and 60 mm, preferably equal to 50 mm, the width being taken along the transverse axis;

[0027] - the protrusion forming at least part of the cells has a length between 90 mm and 130 mm, preferably equal to 110 mm, the length being taken along the longitudinal axis between the front edge of the main body and a free end of said protrusion;

[0028] - a direction of elongation of the protrusions forming the cells is identical for all cells. The direction of elongation of the protrusions forming the cells is parallel or approximately parallel to the longitudinal axis.

[0029] - each cell has a through opening provided on the protrusion. This advantageous configuration makes it easier to deform the cell in the event of frontal impact. More generally, at least part of the cells includes the through opening arranged on the protrusion. The through opening is oriented along the vertical axis. The through opening is formed on an upper face and on a lower face of the corresponding protrusion;

[0030] - more generally, at least part of the cells has a tra opening slope extending between an upper face and a lower face of the corresponding protrusion;

[0031] - the absorption member is made of material with the main body of the ae- deflector By material, we mean that the absorption member and the main body of the air deflector cannot be detached from each other without damaging the main body and / or the absorption member.

[0032] According to a second aspect of the invention, there is provided a motor vehicle comprising a front bumper and an air deflector in accordance with the first aspect of the invention or according to any of its improvements, the air deflector being located under the front bumper and fixed integrally to a lower cross member located behind said front bumper.

[0033] Various embodiments of the invention are provided, integrating according to all of their possible combinations the different optional characteristics set out here.

[0034] 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 appended schematic drawings on the other hand, in which:

[0035] [Fig-1] illustrates a top view of an exemplary embodiment of an aerated deflector raulic conforming to the first aspect of the invention;

[0036] [Fig.2] illustrates a top view of the air deflector of [Fig.l] imparting a device representing a pedestrian's leg.

[0037] 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.

[0038] 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.

[0039] In the figures, the elements common to several figures retain the same reference.

[0040] In the FIGURES described below, a longitudinal axis X, a lateral axis and a vertical axis are defined relative to the motor vehicle on which the air deflector 1 according to the invention is intended to be mounted.

[0041] More particularly, the transverse axis Y 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 Y 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 Y.

[0042] Furthermore, the longitudinal axis X extends as taken along a direction that extends from front to rear or from back to front of the motor vehicle. The longitudinal axis X is perpendicular to the transverse axis Y. The adjectives frontal, front and rear refer to this longitudinal axis X.

[0043] Finally, the vertical axis is understood as being 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 Y and to the longitudinal axis X. The adjectives above and below, or lower and upper refer to this vertical axis.

[0044] [Fig.l] a top view of an exemplary embodiment of an air deflector 1 according to the invention, while [Fig.2] illustrates a top view of the air deflector 1 impacting a device representative of a leg 2 of a pedestrian.

[0045] With reference to FIGURES 1 and 2, the invention relates to an air deflector 1 for a motor vehicle, the air deflector 1 being intended to be fixed securely to a lower cross member located behind the front bumper, the air deflector 1 comprising:

[0046] - a main body 11 which extends under the bumper of the motor vehicle. The main body 11 thus forms a plate of generally rather flat conformation and which extends mainly along the transverse axis Y, between the wheels of the motor vehicle, and along the longitudinal axis X, from a front face of the motor vehicle and towards the passenger compartment;

[0047] - a member 12 for absorbing mechanical energy resulting from a front impact against the air deflector 1, the absorption member 12 extending in projection from a front edge 111 of the main body 11 of the air deflector 1, relative to a longitudinal axis X. The absorption member 12 is configured to absorb mechanical energy from a frontal impact, so as to reduce the quantity of mechanical energy transmitted to the impacted pedestrian and / or to the various elements of the motor vehicle located behind the bumper. The absorption member 12 therefore forms a de- formable along the longitudinal axis X in order to allow such absorption.

[0048] According to the invention, the absorption member 12 comprises a plurality of energy absorption cells 121, spaced apart from each other along a transverse axis Y, so that the absorption member 12 of the air deflector 1 has a comb-shaped geometry. The energy absorption cells 121 form deformable boxes, independently of each other. The absorption cells 121 are located at the front edge 111 of the air deflector 1. The cells 121 thus form three-dimensional modules which are configured to be able to deform under the effect of a frontal impact, typically by compression and / or torsion and / or shearing along the longitudinal axis X, in order to absorb said frontal impact.

[0049] The cells 121 together form a comb structure. Thus, the cells 121 are all equidistant from each other, relative to the transverse axis Y. In particular, a distance d between two adjacent cells 121 is between 40 mm and 90 mm, preferably equal to 65 mm.

[0050] According to a first embodiment, the cells 121 all have identical dimensions and / or shapes. However, in the embodiment illustrated in FIGURES 1 and 2, the cells 121 have variable dimensions depending on their position along the transverse axis Y. These dimensions - their length L2 and / or their width L1 - depend in particular on the geometry of the front face of the bumper. However, it is preferable that the comb formed by the different cells 121 has axial symmetry along the median longitudinal axis X.

[0051] In order to allow better absorption of the mechanical energy resulting from the frontal impact, the cells 121 forming the absorption member 12 form hollow boxes so as to make them more easily deformable and to provide a volume reserve allowing their compression and / or their crushing and / or their deformation, necessary for the dissipation of mechanical energy. For this purpose, each cell 121 comprises a protrusion which extends along the longitudinal axis X from the front edge 111 of the main body 11, the protrusion delimiting a non-zero interior volume. The protrusion advantageously delimits a hollow housing. For example, each cell 121 has a parallelepiped or cylindrical shape or, preferably, a pyramidal shape. In this case, a front part 123 of the protrusion is preferably of lesser thickness than a rear part 124 of the protrusion, the thickness being taken along a vertical axis.

[0052] The cells 121 have a width L1 of between 40 mm and 60 mm, preferably equal to 50 mm, the width L1 being taken along the transverse axis Y.

[0053] The cells 121 have a length L2 of between 90 mm and 130 mm, preferably equal to 110 mm, the length L2 being taken along the longitudinal axis X between the front edge 111 of the main body 11 and a free end of cell 121.

[0054] All the cells 121 extend mainly along the longitudinal axis X.

[0055] The cells 121 further comprise a through opening 122 arranged on an upper face and on a lower face of the protrusion, in order to facilitate the deformation of the cell 121 in the event of a frontal impact.

[0056] In summary, the invention relates to an air deflector 1 for a motor vehicle, the air deflector 1 being intended to be fixed securely to a lower cross member located behind the front bumper, the air deflector 1 comprising:

[0057] - a main body 11 which extends under the bumper of the motor vehicle;

[0058] - a member 12 for absorbing mechanical energy resulting from a front impact against the air deflector 1, the absorption member 12 extending in projection from a front edge 111 of the main body 11 of the air deflector 1, relative to a longitudinal axis X;

[0059] - a plurality of energy absorption cells 121, spaced apart from each other along a transverse axis Y, so that the absorption member 12 of the air deflector 1 has a comb-shaped geometry, each cell 121 forming a hollow box that can be compressed and / or deformed in the event of a frontal impact with a pedestrian. The dimensions and / or thickness of each cell 121, as well as the material used, are sized to allow deformation for a pedestrian impact. The rigidity of each cell 121 is therefore determined for such circumstances of use.

[0060] 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. Aeraulic deflector (1) for a motor vehicle, the aeraulic deflector (1) being intended to be fixed integrally to a lower cross member located behind the front bumper, the aeraulic deflector (1) comprising: - a main body (11) which extends under the bumper of the motor vehicle; - a member (12) for absorbing mechanical energy resulting from a front impact against the aeraulic deflector (1), the absorption member (12) extending projecting from a front edge (111) of the main body (11) of the aeraulic deflector (1), relative to a longitudinal axis (X); characterized in that the absorption member (12) comprises a plurality of energy absorption cells (121), spaced apart from each other along a transverse axis (Y), so that the absorption member (12) of the air deflector (1) has a comb-shaped geometry.

2. Air deflector (1) according to the preceding claim, in which a distance (d) between two adjacent cells (121) is between 40 mm and 90 mm, preferably equal to 65 mm.

3. Air deflector (1) according to any one of the preceding claims, in which the cells (121) all have identical dimensions and / or shapes.

4. Air deflector (1) according to any one of the preceding claims, in which each cell (121) comprises a protrusion which extends along the longitudinal axis (X) from the front edge (111) of the main body (11), the protrusion delimiting a non-zero interior volume.

5. Air deflector (1) according to the preceding claim, in which the protrusion forming at least part of the cells (121) has a pyramidal shape, a front part (123) of the protrusion being of lesser thickness than a rear part (124) of the protrusion, the thickness being taken along a vertical axis.

6. Air deflector (1) according to any one of claims 4 or 5, in which the protrusion forming at least part of the cells (121) has a width (L1) of between 40 mm and 60 mm, preferably equal to 50 mm, the width (L1) being taken along the transverse axis (Y).

7. Air deflector (1) according to any one of claims 4 to 6, in which the protrusion forming at least part of the cells (121) has a length (L2) of between 90 mm and 130 mm, preferably equal to 110 mm, the length (L2) being taken along the longitudinal axis (X) between the front edge (111) of the main body (11) and a free end of said protrusion.

8. Air deflector (1) according to any one of claims 4 to 7, in which a direction of elongation of the protrusions forming the cells (121) is identical for all the cells (121).

9. Air deflector (1) according to any one of claims 4 to 8, in which at least a portion of the cells (121) comprises a through opening (122) extending between an upper face and a lower face of the corresponding protrusion.

10. Motor vehicle comprising a front bumper and an air deflector (1) according to any one of the preceding claims, the air deflector (1) being located under the front bumper and fixedly attached to a lower cross member located behind said front bumper.

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