FR3141432A1 - One-piece cross member for automobile vehicle dashboard - Google Patents

Abstract

The invention proposes a one-piece crosspiece (33) for a motor vehicle dashboard which has a structure delimiting a passenger compartment. The one-piece cross member passes through the passenger compartment of the motor vehicle and maintains an external skin forming an internal trim. The one-piece crossmember includes: a front face; a back side; two opposite transverse ends (42); a transverse portion connecting the transverse ends; a steering column fixing plate (50) linked to the transverse portion; each transverse end comprises a fixing block (60) with a front portion (62) and a rear portion (64), the front portion comprising a lower extension (66) with an abutment surface (68) abutting against the structure of the motor vehicle. The one-piece crosspiece is made by additive manufacturing. The invention also proposes a motor vehicle with a one-piece crossmember. Figure to be published with the abstract: Figure 3

Description

One-piece cross member for automobile vehicle dashboard

The invention relates to the low transverse overlap front collision of a motor vehicle. The invention relates more specifically to a reinforced dashboard crossmember of a motor vehicle. The invention also relates to a motor vehicle.

A motor vehicle includes a dashboard in front of the passenger compartment. A dashboard forms an interior trim piece passing through the vehicle. In doing so, the dashboard covers and surrounds different organs. For example, air vents or screens forming human-machine interfaces are embedded there. Airbag safety features are also housed underneath. The elasticity of its skin allows it to absorb slight shocks.

Due to the elongated nature and flexibility of the skin which forms an internal trim, the dashboard has a metal beam arranged transversely. This beam supports the skin and receives the steering column. In order to fulfill all these functions, the dashboard assembly makes the motor vehicle heavier and impacts the consumption of driving energy.

Due to evolving safety standards, motor vehicles must meet drastic criteria. In the context of forward collisions, a motor vehicle must have minimum absorption in the event of total coverage. In the event of 50% partial coverage, the motor vehicle complies with certain requirements thanks to reinforcements and dedicated shock absorbers. However, these same reinforcements and absorbers show limited effectiveness when the coverage drops to 25%, and the impact speed is 64 km/h against a fixed obstacle. Such a collision is referred to as a small overlap collision.

Document FR2975963A1 presents a motor vehicle with a dashboard in front of the passenger compartment, and at the base of the windshield. The dashboard is supported by a lower reinforcement piece. It is intended to be secured at the rear face of said dashboard and is made at least partly of textile composite. The reinforcing part comprises a main support element to which a series of longitudinal ribs and a series of transverse ribs are fixed. The crossmember incorporates two mounting tabs to the dashboard arranged at each of the opposite ends of the crossmember as well as two mounting elements for the crossmember on the body of the vehicle also arranged at each of the opposite ends of the crossmember. Such a crossmember is satisfactory in terms of resistance to the vibration frequency of the steering column and resistance to frontal and lateral impacts of the vehicle. However, there is a need to further improve safety in the event of a small overlap collision.

The invention aims to respond to at least one of the problems or disadvantages encountered in the prior art. In particular, the invention aims to improve the safety of a motor vehicle in the event of a small overlap collision. The invention also aims to optimize the assembly costs, the mass and the safety of a motor vehicle in the event of a low-overlap collision.

According to a first aspect, the invention proposes a one-piece dashboard cross member of a motor vehicle which has a structure; the one-piece crosspiece being intended to support an exterior dashboard skin; the one-piece crosspiece comprising: two opposite transverse ends; a transverse portion connecting the transverse ends; a steering column fixing plate linked to the transverse portion; remarkable in that at least one or each transverse end comprises a fixing block with a front portion and a rear portion, the front portion comprising a lower extension with an abutment surface intended to abut against the structure of the motor vehicle.

Preferably, at least one or each lower extension comprises a horizontal branch extending forward, the abutment surface being at the front end of said horizontal branch.

Preferably, at least one or each fixing block comprises two plates spaced transversely and connected by internal ribs.

Preferably, at least one or each front portion of the fixing block comprises a lower column extending forward; the lower extension extending longitudinally from said lower column.

Preferably, the one-piece crosspiece comprises at least one arm connecting the transverse portion to one of the two fixing blocks.

Preferably, the arm is inclined relative to the transverse portion and the associated fixing block.

Preferably, at least one or each lower extension comprises means for fixing to the structure of the motor vehicle, said fixing means passing through the abutment surface.

Preferably, the abutment surface is generally horizontal.

Preferably, the one-piece crosspiece comprises a metal profile, and a body of plastic material overmolded on the metal profile and forming at least one or each lower extension.

Preferably, the transverse portion is a rear transverse portion, the one-piece crosspiece further comprising a front transverse portion connecting the fixing blocks and arranged above the rear transverse portion, said front transverse portion having a front edge intended to hold the skin exterior.

Preferably, at least one or each rear portion of the fixing block comprises a rear leg longitudinally opposite the lower extension, said rear leg being intended to hold the exterior dashboard skin.

It will be clearly understood that the invention proposes a one-piece crosspiece with massive fixing ends, which have front stops in the lower part.

Thus, the invention provides robust fixing of the one-piece crosspiece, and ensures front support thanks to the stop against the structure. Thus, the invention limits the rotation of the one-piece crossmember while stiffening the motor vehicle at the front corners of the passenger compartment. Thus, the one-piece crossmember provides a dual function: skin support and passenger safety.

Preferably, the abutment surface is vertically and/or longitudinally abutting against the structure.

Preferably, the one-piece crosspiece has a front face and a rear face opposite the front face, the front part being on the front face.

Preferably, the one-piece crosspiece comprises a lower central leg.

Preferably, the one-piece crossmember comprises a steering column fixing plate.

Preferably, the one-piece crosspiece includes ventilation openings.

Preferably, the abutment surface is oriented downwards.

According to another aspect, the invention proposes a dashboard assembly for a motor vehicle, said assembly comprising a one-piece crosspiece and an outer skin carried by the one-piece crosspiece, remarkable in that the one-piece crosspiece conforms to the invention.

According to another aspect, the invention proposes a one-piece dashboard crossmember of a motor vehicle having a structure delimiting a passenger compartment; the one-piece crosspiece being intended to run transversely through the passenger compartment of the motor vehicle; and comprising: a front face; a rear face opposite the front face; two opposite side ends, each side end comprising a fixing plate with an upper portion and a lower portion; a transverse portion connecting the fixing plates; remarkable in that at least one or each lower portion of fixing plate comprises a front zone with an abutment surface intended to abut against the structure of the motor vehicle; said front zone comprising a front extension extending forward; optionally each fixing plate is integrated into one of the fixing blocks.

According to another aspect, the invention proposes a motor vehicle comprising a structure delimiting a passenger compartment, a one-piece dashboard crosspiece, remarkable in that the one-piece crosspiece conforms to the invention.

Preferably, the motor vehicle comprises front wheels, at least one or each lower extension extending towards one of said front wheels.

Preferably, the structure comprises a front apron delimiting the passenger compartment, at least one or each abutment surface abutting against the front apron; or the structure comprises a front pillar, one of the two abutment surfaces abutting against the front pillar.

Preferably, the structure comprises two opposite side walls facing each other; the fixing plates being fixed to said side walls.

According to another aspect, the invention proposes a motor vehicle comprising a dashboard assembly, remarkable in that the dashboard assembly conforms to the invention.

The invention will be well understood and other aspects and advantages will appear clearly on reading the description which follows given with reference to the figures appended and listed below.

There is a side view of a motor vehicle according to the invention.

There is a top view of a portion of a motor vehicle structure according to a first embodiment of the invention.

There is an isometric view of a one-piece crossmember of a motor vehicle according to a first embodiment of the invention.

There represents a fixing interface at a transverse end of the one-piece crossmember of a motor vehicle according to the first embodiment of the invention.

There is an isometric view of a one-piece crossmember of a motor vehicle according to a second embodiment of the invention.

In the following description, the term “include” is synonymous with “include” and is not restrictive in that it authorizes the presence of other elements in the motor vehicle or the one-piece crossmember to which it relates. It is understood that the term “understand” includes the terms “consist of”. The terms “external” and “internal” will respectively designate what is oriented towards the exterior of the vehicle and towards the interior of the vehicle.

In this description, the term “longitudinal”, the term “longitudinal”, the term “transverse”, and the term “transversely” are used according to the reference of the vehicle, in the assembly configuration. The term “longitudinal” corresponds to the main direction of movement of the vehicle. The term “transverse” corresponds to a direction perpendicular to the main direction of movement of the vehicle. The term “front” refers to the main direction of movement of the vehicle. The term “rear” refers to the opposite of the front of the vehicle.

The X axis represents the longitudinal direction, the Y axis represents the transverse direction, and the Z axis represents the vertical direction. These three axes define a trihedron whose orientation is preserved throughout the figures.

In this description, the value ranges include the limits which delimit them.

Through the description, the different figures use the same reference signs to designate identical or similar entities.

There represents a motor vehicle 10 according to the invention. The motor vehicle 10 comprises energy storage means and at least one motor (not shown) adapted to drive said motor vehicle 10.

The motor vehicle 10 comprises a structure 12. The structure 12 is adapted to support various components of the vehicle including the engine or side openings. Structure 12 forms a box. It can be made by assembling stamped and welded sheets together. Structure 12 delimits different compartments including the rear trunk, the front engine compartment, and the passenger compartment 14 which is between the latter two. The passenger compartment 14 is intended to accommodate the occupants of the motor vehicle 10, for example at least four occupants.

The structure 12 has at least one front pillar 16, preferably two front pillars 16. The front pillars 16 border the windshield 18, and support the roof. According to one option, the front pillars 16 extend under the windshield 18. They can extend to the level of the front engine compartment of the motor vehicle 10.

The structure 12 also includes a front apron 20. The front apron 20 delimits the front of the passenger compartment 14, in the lower part; and separates it from the front compartment. The front apron 20 can be made of sheet metal, it extends from the floor of the passenger compartment 14. The front apron 20 is arranged under the windshield 18.

The motor vehicle 10 has two side walls 22. The side walls 22 are transversely opposed. They are facing each other. They may include portions of the structure 12 and side openings.

The motor vehicle 10 also includes a dashboard assembly 24. The dashboard assembly 24 extends transversely over the entire width of the passenger compartment 14. The dashboard assembly 24 extends from a side wall 22 to the other. The dashboard assembly 24 is arranged at the base of the windshield 18; and overlooks the front apron 20.

The dashboard assembly 24 advantageously comprises a crosspiece and a skin (not shown). The skin covers the crosspiece. The skin may be a rear covering, covering the rear and top of the dashboard assembly 24. The skin may be an external trim. The crosspiece may be a one-piece crosspiece. The one-piece appearance makes it more rigid.

The motor vehicle 10 comprises a front axle with front wheels 26, and a rear axle with rear wheels 28. According to one option, the dashboard assembly 24 extends vertically at the level of the front wheels 26. Thus, in in the event of an impact with a 25% overlap, in particular at a speed of at least 64 km/h, the impacted front wheel 26 is likely to move backwards relative to the structure 12 and to encounter the dashboard assembly 24 ; or at least its lower portion.

There presents an aerial view of a portion of structure 12 of a motor vehicle. The motor vehicle may correspond to that presented in relation to the . Seats and trim are not shown for clarity.

This portion comprises a part of the passenger compartment 14 and a part of the structure 12 of which we observe the floor 30 and two central spars 32 delimiting the floor 30. The central spars 32 are lateral spars. The central longitudinal members 32 are arranged between the front axle and the rear axle. The passenger compartment 14 has a transverse width L. The transverse width L extends substantially over the entire width of the motor vehicle.

The dashboard assembly 24 has a one-piece crosspiece 33 for holding the exterior skin (not shown), also called the trim skin. The outer skin partially hides the front apron 20. The one-piece appearance of the one-piece crossmember 33 allows it to have better resistance in the event of a collision; which increases security. The one-piece crosspiece 33 extends over the transverse width L of the passenger compartment 14. Their widths are substantially equal.

The one-piece crosspiece 33 comprises at least one transverse portion 34. The transverse portion 34 passes horizontally through the passenger compartment 14, from one side wall 22 to the other. The transverse portion 34 is generally horizontal. It generally forms a beam. It may be a rear transverse portion 36, also called first transverse portion. The dashboard assembly 24 further comprises a second transverse portion, also called front transverse portion 38. The front transverse portion 38 is in front of the rear transverse portion 36. The front transverse portion 38 comprises a front edge 40. The front edge 40 is intended to fit the windshield. The front edge 40 is convex. It is intended to hold the outer skin along the windshield.

The one-piece crosspiece 33 comprises two opposite transverse ends 42; including a left end and a right end which are each in contact with the side walls 22 for their attachment. The transverse ends 42 are opposite in the transverse direction. Each transverse end 42 can be a lateral end. Furthermore, the one-piece crosspiece 33 has a front face 44; and a rear face 46 towards the passenger compartment 14. On the rear side 46, and therefore towards the passenger compartment 14, the one-piece cross member 33 has a steering column fixing plate 50, ventilation openings 52. The upper branches 54 helps maintain the outer skin. The front transverse portion 38 and the rear transverse portion 36 each connect the transverse ends 42.

According to an alternative of the invention, the front transverse portion is an attached element.

There presents an isometric view of the one-piece crossmember 33 of a motor vehicle. The motor vehicle may correspond to that presented in relation to one of Figures 1 to 2.

The present view shows the steering column fixing plate 50, the ventilation openings 52 as well as several upper branches 54 make it possible to position and support the outer skin (not shown). The one-piece crosspiece 33 also has a lower central leg 56. The lower central leg 56 is intended to rest on the structure. Thus, it prevents the one-piece crosspiece 33 from bending, and limits its pivoting around the Y axis.

The steering column fixing plate 50 is in the lower part of the one-piece crossmember 33. Thus, the steering column (not shown) pivots under, and goes around from below, the one-piece crossmember 33. The steering column fixing plate 50 may include a plate, possibly slotted for the passage of the steering column. The steering column fixing plate 50 also has fixing holes for fixing a rotating connection of the steering column, and maintaining the orientation of the axis of rotation of the steering column. Furthermore, the steering column fixing plate 50 is eccentric laterally in order to be on the driver's side.

The steering column mounting plate 50, the upper branches 54 and the lower central leg 56 extend from the rear transverse portion 36. At least one or each of these entities can be used to distinguish the front from the rear of the one-piece crosspiece 33; but also the front face 44 of the rear face 46. Openings 58 are provided between the rear transverse portion 36 and the front transverse portion 38. The openings 58 pass vertically through the one-piece crosspiece 33.

In the remainder of the description and for the sake of brevity, the one-piece crosspiece 33 will be detailed in relation to one of its transverse ends 42, for example the left. However, this description applies to each transverse end 42 of the one-piece crosspiece 33.

The transverse end 42 comprises a fixing block 60. The fixing block 60 is intended to fit the structure of the motor vehicle. The fixing block 60 includes means for fixing to the structure. The fixing block 60 comprises two plates spaced transversely apart and connected by internal ribs. The internal ribs can define a reinforcing mesh between the plates. This achievement improves rigidity, while maintaining stiffness in the event of a collision. Furthermore, the fixing block 60 has a solid appearance, which improves its anchoring to the transverse portion. This limits the pivoting of the fixing block 60 around the Y axis relative to the transverse portion. Rigidity and therefore safety are reinforced.

The fixing block 60 has a front portion 62 and a rear portion 64. The front portion 62 comprises a lower extension 66 with an abutment surface 68 intended to abut against the structure of the motor vehicle. The abutment surface 68 is vertically and/or longitudinally abutting against and/or in contact with the structure. The abutment surface 68 is generally horizontal so as to ensure rotational locking around the axis Y of the one-piece crosspiece 33. In addition, this orientation improves the retention of the one-piece crosspiece 33 on the structure.

The rear portion 64 of the fixing block comprises a rear leg 65 longitudinally opposite the lower extension 66, said rear leg 65 makes it possible to maintain the outer skin (not shown). The positioning of the rear leg 65 at the transverse end 42 allows the skin to be maintained from one end to the other.

The lower extension 66 comprises a horizontal branch 70 extending towards the front, the abutment surface 68 being at the front end of said horizontal branch 70. The abutment surface 68 being at the front end of the horizontal branch 70. The branch horizontal 70 allows the abutment surface 68 to be offset and to seek support against the structure. The rotational locking of the one-piece crosspiece 33 is made easier.

The front portion 62 of fixing block 60 comprises a lower column 72 extending forward and downward. The lower column 72 extends vertically along the rear leg 65. The lower extension 66 extends longitudinally from said lower column 72.

The lower extension 66 includes means of attachment to the structure of the motor vehicle. These fixing means may include a fixing orifice intended to receive a screw cooperating with the structure. Alternatively, they may comprise latching means intended to cooperate with a complementary orifice in the structure of the motor vehicle. The fixing means passing through the abutment surface 68. They are at the front end of the lower extension 66, and of the optional horizontal branch 70.

There has a transverse end 42 of the one-piece crosspiece 33 (partially shown), in this case the right side. The motor vehicle may correspond to that presented in relation to one of Figures 1 to 3. The description which follows is in relation to one of the two transverse ends 42, however it applies to both. A portion of the structure 12 of the motor vehicle is shown. A lower section of the front pillar 16 is visible.

The one-piece crosspiece 33 is fixed laterally to the structure 12. In particular, the fixing block 60 is connected to the side wall 22. The latter may have mounting holes to hold the one-piece crosspiece 33 there with fixing pins.

The fixing block 60 rests against the structure 12. In particular, it rests against the front apron 20. At this location, it is likely to limit the intrusion of the right front wheel in the event of a collision with a covering of around 25%. The abutment surface (not visible) of the fixing block 60 cooperates with the rear surface 74 of the front apron 20. The rear surface 74 faces the passenger compartment. The fixing block 60 comprises two plates spaced transversely apart and connected by internal ribs.

The front transverse portion 38 is optionally in elevation relative to the rear transverse portion 36 (partially shown). The rear leg 65 vertically overlaps the fixing block 60.

The one-piece crosspiece 33 comprises at least one arm 76 connecting the fixing block 60 to one of the transverse portions; in this case the rear transverse portion 36. The arm 76 is inclined relative to the transverse portion and the fixing block 60. The arm 76 forms a connecting arc connecting the transverse portion and the fixing block 60. The one-piece crosspiece 33 has a passage 78 surrounded by the arm 76, the transverse portion and the fixing block 60. The passage 78 extends longitudinally and crosses the one-piece crosspiece 33.

The arm 76 forms a buttress between the fixing block 60 and the rear transverse portion 36. It prevents the fixing block 60 from tilting around the axis 76 contributes to limiting the pivoting around the Y axis of the fixing block 60 relative to the rear transverse portion 36. The presence of the front transverse portion 38 further limits this risk of pivoting around the Y axis, in addition to limit the pivoting around the axis X. Thus, the one-piece crosspiece 33 stiffens the structure 12 as a whole.

So the invention generates a double reinforcement. The pivoting along the X axis and the Y axis is limited by the configuration of the one-piece crosspiece 33.

According to one embodiment, the one-piece crosspiece 33 is made from material. It may comprise a plastic material, such as polyamide (PA) or polyurethane (PU). The one-piece crosspiece 33 may comprise a composite material. It can be made by molding.

According to yet another alternative, it can be produced by three-dimensional printing; also called additive manufacturing. Additive manufacturing makes it possible to produce the one-piece sleeper in a succession of superimposed layers.

According to another alternative, the one-piece crosspiece 33 comprises a metal profile and an overmolding of plastic material on the metal profile. The overmolding forms each fixing block, and in particular each lower extension.

There presents a one-piece crossmember 33 for a motor vehicle according to a second embodiment of the invention. The motor vehicle can generally correspond to that presented in relation to one of the preceding figures. The one-piece crosspiece 33 is similar to that of the first embodiment, but differs from it in that the front transverse portion 38 (represented by its ends) is an element attached and fixed to the one-piece crosspiece 33.

The fixing blocks 60 are connected by the rear transverse portion 36 so as to form a single-piece entity. The fixing blocks 60 include upper fixing wings 80 of the front transverse portion 38. The upper fixing wings 80 extend upwards. The front transverse portion 38 comprises fixing lugs 82 mounted on the upper fixing wings 80. The fixing lugs 82 are at the transverse ends 42. The fixing lugs 82 and the upper fixing wings 80 can be fixed by screws or clips .

Claims (10)

One-piece cross member (33) of a motor vehicle dashboard (10) which has a structure (12); the one-piece crosspiece (33) being intended to support an exterior dashboard skin; the one-piece crosspiece (33) comprising: two opposite transverse ends (42); a transverse portion (34) connecting the transverse ends (42); a steering column fixing plate (50) linked to the transverse portion (34); characterized in that at least one or each transverse end (42) comprises a fixing block (60) with a front portion (62) and a rear portion (64), the front portion (62) comprising a lower extension ( 66) with an abutment surface (68) intended to abut against the structure (12) of the motor vehicle (10). One-piece crosspiece (33) according to claim 1, characterized in that at least one or each lower extension (66) comprises a horizontal branch (70) extending towards the front, the abutment surface (68) being at the end front of said horizontal branch (70), preferably at least one or each fixing block comprises two plates spaced transversely and connected by internal ribs. One-piece crosspiece (33) according to one of claims 1 to 2, characterized in that at least one or each front portion (62) of fixing block (60) comprises a lower column (72) extending towards the Before ; the lower extension (66) extending longitudinally from said lower column (72). One-piece crosspiece (33) according to one of claims 1 to 3, characterized in that the one-piece crosspiece (33) comprises at least one arm (76) connecting the transverse portion (34) to one of the two fixing blocks ( 60), the arm (76) being preferentially inclined relative to the transverse portion (34) and the associated fixing block (60). One-piece cross member (33) according to one of claims 1 to 2, characterized in that at least one or each lower extension (66) comprises means for fixing to the structure (12) of the motor vehicle (10), said means fastener passing through the abutment surface (68); the abutment surface (68) being preferably generally horizontal. One-piece crosspiece (33) according to one of claims 1 to 5, characterized in that the one-piece crosspiece (33) comprises a metal profile, and a body of plastic material overmolded on the metal profile and forming at least one or each lower extension (66). One-piece cross member (33) according to one of claims 1 to 6, characterized in that the transverse portion (34) is a rear transverse portion (36), the one-piece cross member (33) further comprising a front transverse portion (38) connecting the fixing blocks (60) and arranged above the rear transverse portion (36), said front transverse portion (38) having a front edge (40) intended to hold the outer skin. One-piece crosspiece (33) according to one of claims 1 to 7, characterized in that at least one or each rear portion (64) of fixing block (60) comprises a rear leg (65) longitudinally opposite to the lower extension (66), said rear leg (65) being intended to hold the exterior dashboard skin. Motor vehicle (10) comprising a structure (12) delimiting a passenger compartment (14), a one-piece dashboard crossmember (33), characterized in that the one-piece crossmember (33) conforms to one of claims 1 to 8 ; preferably the motor vehicle (10) comprises front wheels (26), at least one or each lower extension (66) extending towards one of said front wheels (26). Motor vehicle (10) according to claim 9, characterized in that the structure (12) comprises a front apron (20) delimiting the passenger compartment (14), at least one or each abutment surface (68) abutting against the front apron (20); or the structure (12) comprises a front pillar (16), one of the two abutment surfaces (68) abutting against the front pillar (16).