Handlebar or wishbone and method for producing such a handlebar or wishbone

Abstract

The invention relates to a suspension support element (10) for a motor vehicle, such as a suspension arm or triangle, comprising a body (100) adapted to secure a wheel to a chassis of the motor vehicle, and at least one air deflector (200, 300) which forms a single monobloc piece with said body.

Description

TECHNICAL FIELD OF THE INVENTION

[0001] The present invention relates generally to the field of automobiles.

[0002] It relates more specifically to a suspension support element for a motor vehicle, such as a suspension arm or triangle, comprising a body adapted to secure a wheel to a chassis of the motor vehicle.

[0003] It also relates to a manufacturing process for such a suspension support element. STATE OF THE ART

[0004] In a motor vehicle's running gear, there are two wheels, each equipped with a hub, a hub carrier (or "stub axle") which allows the hub to rotate, and at least one suspension support element which connects the hub carrier to the vehicle's chassis and on which a shock absorber is attached.

[0005] This suspension support element can typically take the form of a suspension arm or triangle.

[0006] It is a part that is mounted on the side of the chassis, so that it can pivot around a longitudinal axis of the vehicle when the vehicle's suspension compresses or extends, and which supports the hub carrier at its end.

[0007] This part is therefore under considerable stress and plays a fundamental role in the vehicle's road handling.

[0008] It is generally produced during a foundry operation, in metallic material, for example in aluminum alloy.

[0009] Alongside this suspension arm or triangle, it is known to install a scoop which allows a portion of the airflow circulating under the car to be diverted towards the brake disc of the corresponding wheel, in order to accelerate its cooling when the vehicle is moving.

[0010] This scoop is usually made by molding a plastic material. It is then screwed onto one of the corresponding components of the vehicle's suspension. PRESENTATION OF THE INVENTION

[0011] The present invention aims to simplify the architecture of a motor vehicle's running gear and to reduce its weight.

[0012] More in particular, the invention proposes a suspension support element as defined in the introduction, in which there is provided at least one aerodynamic appendage which is adapted to modify the airflow around said body when the motor vehicle moves forward and which forms a single monobloc piece with said body.

[0013] A single-piece component is defined as one formed from a single piece, meaning they are produced through a single manufacturing process. Therefore, they have no means of fastening to each other. They are inseparable (unless broken). This eliminates the need to assemble these two components, reducing the weight of the vehicle's running gear and simplifying assembly.

[0014] Furthermore, thanks to the invention, the suspension arm or triangle can simultaneously perform several functions, including a mechanical function which consists of connecting the wheel to the chassis and an aerodynamic function which consists, for example, of deflecting air towards the vehicle's braking system.

[0015] Finally, the aerodynamic appendage, which fulfills the second of these functions, helps to contribute to the rigidity of the body, so that it is possible to lighten the latter accordingly.

[0016] Other advantageous and non-limiting features of the suspension support element according to the invention, taken individually or in all technically possible combinations, are as follows: said at least one aerodynamic appendage is formed by a plate less than 3 millimeters thick; said body and each aerodynamic appendage are formed by additive manufacturing; said body and each aerodynamic appendage are formed in the same material; said at least one aerodynamic appendage includes an air deflector; said at least one aerodynamic appendage includes a cooling scoop for a braking system of the motor vehicle; said at least one aerodynamic appendage includes at least one substantially flat wall (within the curvatures necessitated by the non-planar shape of the body to which it relates) and located in a plane substantially parallel to the average plane of the body (for example within 10 degrees); said at least one wall has at least one opening.

[0017] The invention also relates to a method for manufacturing such an element, which comprises a simultaneous forming operation of said body and each aerodynamic appendage. Other advantageous and non-limiting features of the manufacturing method according to the invention, taken individually or in all technically possible combinations, are as follows: said body and each aerodynamic appendage are formed by additive manufacturing; said body extending in a mean plane, during the forming operation, the mean plane of said body is inclined to the vertical at an angle of less than 30 degrees, preferably less than 10 degrees; during the forming operation, supports which support said body are formed simultaneously with said body and after the forming operation, a finishing operation is provided during which the supports are cut from said body.

[0018] Of course, the different features, variants and embodiments of the invention can be combined with each other in various ways as long as they are not incompatible or mutually exclusive. DETAILED DESCRIPTION OF THE INVENTION

[0019] The description that follows, with regard to the attached drawings, given by way of non-limiting examples, will make it clear what the invention consists of and how it can be carried out.

[0020] Regarding the attached drawings: [ Fig. 1 ] is a schematic view of part of a front running gear of a motor vehicle; [ Fig. 2 ] is a schematic view, from a first angle, of a suspension triangle according to the invention of the running gear of the figure 1 ; Fig. 3 ] is a schematic view, from a second angle, of the suspension triangle of the figure 2 ; And [ Fig. 4 ] is a schematic view, from a third angle, of the suspension triangle of the figure 2 .

[0021] In the following description, the motor vehicle will be considered to be situated on a horizontal road. The terms upper and lower will then be used in relation to this configuration. The terms front and rear will also be used in relation to the vehicle, with front referring to the side facing the front of the vehicle and rear referring to the opposite side.

[0022] On the figure 1 , we have represented, in perspective seen from the rear, a left part of a front axle 1 of a motor vehicle, here a car.

[0023] This left part of the front axle 1 includes a wheel and its hub, as well as a shock absorber, which elements are not shown for clarity in the figures.

[0024] It also features a braking system comprising a brake disc 6 fixed to the wheel and a brake caliper 5.

[0025] The brake caliper 5 is fixed to a hub carrier 4.

[0026] This hub carrier 4 therefore supports the brake caliper 5 but also the hub of the corresponding wheel so that the wheel can pivot relative to this hub carrier 4.

[0027] Hub carrier 4 is articulated on at least one suspension support element.

[0028] Here, it is articulated, at its lower part, on a lower suspension triangle 10 and, at its upper part, on an upper suspension triangle 2. This configuration of superimposed triangles is only an illustrative example in that a configuration using a single suspension triangle per wheel could also be used.

[0029] The hub carrier joints 4 on the two suspension triangles allow this hub carrier to pivot around a substantially vertical axis to steer the vehicle in the desired direction.

[0030] The upper suspension triangle 2 has a V-shape, with two ends hinged to the vehicle chassis so that the triangle can pivot relative to the chassis around a substantially horizontal axis, allowing the wheel to rise relative to the chassis when the suspension is compressed or to fall when the suspension is extended.

[0031] This upper suspension triangle 2 is also mounted, at the bottom of the V, on the hub carrier 4 using a ball joint.

[0032] The lower suspension triangle 10 is more precisely represented on the figures 2 à 4 This is the one that is more specifically the subject of the present invention described below. On the figure 1 , we observe an anti-roll bar 3 which is connected to this suspension triangle 10.

[0033] Here, the unshown shock absorber is also connected to this suspension triangle 10, at the same level as the anti-roll bar 3.

[0034] This suspension triangle 10 is designed to be installed approximately horizontally in the vehicle.

[0035] As shown by figure 2 , it first includes a body 100 which provides the function of linking the dead hub 4 to the chassis of the vehicle.

[0036] As the figure 4 The body 100 has an inclined T-shaped arm 110. More precisely, this arm 110 comprises a first part 111 (the base of the T) which extends in a substantially straight line, and a second part (the cap of the T) which also extends in a substantially straight line. These two parts 111 and 112 are inclined to each other at an angle of approximately 60 degrees. This shape of the arm 110 is, of course, only a non-limiting example.

[0037] Arm 110 could be solid. However, as the figures clearly show, it has several openings that allow it to be lightened without compromising its structural characteristics. Furthermore, it is hollow in that it contains internal cavities (not visible) which also contribute to its lightness.

[0038] The body 100 is designed to accommodate connections allowing it to be attached, on one side, to the chassis, and, on the other, to the hub carrier 4.

[0039] Here, it is planned that the body 100 can accommodate a ball joint type linkage (with three degrees of rotational freedom) for its attachment to the hub carrier 4, and exactly two ball joint type linkage means for its attachment to the chassis.

[0040] These means of connection can take various forms. For example, they can be metal ball joints screwed or crimped into the body 100, or rubber bushings (more commonly referred to by the English term "bushings").

[0041] In practice, here, the body 100 has, at the free end of the first part 111 of the arm 110, a first socket 120 in the shape of an eyelet into which a rubber ring can be forced.

[0042] It also includes, at one end of the second part 112 of the arm 110, a second tube-shaped socket 130 into which another rubber ring can be force-fitted.

[0043] The two rubber rings allow the suspension triangle 10 to be connected to the vehicle chassis, so that the arm 110 can pivot around a longitudinal axis of the vehicle when the shock absorber compresses or extends.

[0044] The body 100 also includes, at the other end of the second part 112 of the arm 110, a third socket 140 in the shape of an eyelet into which a metal ball joint can be screwed (for its attachment to the hub carrier 4).

[0045] Finally, within the arm 110 and near this third socket 140, it includes a fourth tubular socket 150 on which one end of the shock absorber can be articulated.

[0046] Body 100 has an upper face and, opposite, a lower face intended to be turned towards the road.

[0047] As the figures 2 And 3, the suspension triangle 10 also includes at least one aerodynamic appendage 200, 300. Here, it includes several.

[0048] One of these aerodynamic appendages is a deflector. More specifically, it is a brake cooling scoop, hereafter referred to as scoop 200, which serves to improve cooling of the braking system when the vehicle is moving. The other of these aerodynamic appendages is an aerodynamic screen 300, which serves to reduce the drag generated by the suspension triangle when the vehicle is moving.

[0049] The scoop 200 takes the form of a wall facing the airflow passing under the vehicle as it moves forward.

[0050] It thus presents a face 201 oriented towards the front of the vehicle. This face has a surface that is preferably continuous. Here, it is substantially flat, except for its end facing the wheel, which is slightly curved towards the rear in order to guide the diverted airflow towards the desired area of ​​the braking system.

[0051] Here, and preferentially, the scoop 200 is presented in the form of a plate which has a thickness at every point less than 2 mm, here approximately equal to 1 mm.

[0052] This scoop 200 rises from the upper face of the second part 112 of the arm 110 of the body 100. It rises in a direction orthogonal to the mean plane of the arm 110. This scoop 200 runs along the front edge of the second part 112 of the arm 110 of the body 100, between the two sockets 130, 140. It has a height that increases from the second socket 130 to the third socket 140.

[0053] According to the invention, the scoop 200 is formed in one piece with the body 100.

[0054] It is made of the same material as the latter, namely aluminum alloy. The aerodynamic screen 300's function is to reduce the drag generated by the suspension triangle 10 when the vehicle is moving forward.

[0055] It could be in the form of a large plate located under the body 100. However, here it has two distinct walls 310, 320, located on either side of the arm 110 of the body 100.

[0056] These two walls 310, 320 are more precisely provided on either side of the first part 111 of the arm 110 (the foot of the T), and extend from the first socket 1120 to the ends of the second part 112 of the arm 110.

[0057] These are flat plates with thicknesses of less than 2 mm, here approximately equal to 1 mm. These two walls 310, 320 are substantially flat and extend parallel to the average plane of the body 100. They extend more precisely at the lower face of the arm 110.

[0058] They can be described as air deflectors in that they are perforated. They have one and two openings 311 and 321 respectively, whose asymmetrical shapes allow the air passing under the vehicle to be diverted in the desired direction, for example towards the braking system, or towards the left front wheel arch of the vehicle, or in a direction that provides better aerodynamic support to the motor vehicle.

[0059] The suspension triangle 10 is here made in two successive operations.

[0060] The first step is to manufacture this triangle by an additive process, using a device commonly called a 3D printer.

[0061] Here, the process used is powder bed fusion using a laser (typically, it may be the DMLS method from the English "Direct Metal Laser Sintering"), but other technologies could be used.

[0062] The triangle is therefore created layer by layer, by placing a new layer of powder on the last layer fused by laser.

[0063] The suspension triangle is therefore produced along an extrusion direction orthogonal to the layers. This direction is preferably substantially orthogonal to the average plane of the suspension triangle. As a result, the triangle can be produced quickly, avoiding any deformation that would be due to an overhanging position of the part being manufactured.

[0064] This also allows the two lower suspension triangles of the front axle of a vehicle to be produced simultaneously, side-by-side, with a 3D printer of small dimensions.

[0065] During this step, the body 100 is formed at the same time as the deflectors 200, 300. It is further formed jointly with a support.

[0066] This support provides a stable base for the body 100 on the 3D printer's build plate. The support is therefore formed as a single piece with the suspension triangle 10 itself. Once the triangle has been manufactured, the support must be removed from the triangle.

[0067] For this purpose, a finishing operation is planned here in which the support is cut from the body 100 using an industrial saw, and then in which the raw cut piece is graveled to give the suspension triangle 10 an adequate surface finish.

[0068] The bushings can then be bored to allow for a proper fit of the connecting means, particularly the ball joints.

[0069] Naturally, the front right axle of the vehicle will preferably be equipped with a suspension triangle of the same type as that described above.

[0070] It could also be expected that the rear suspension triangles of the vehicle are also of the same type, and that they thus include at least one aerodynamic appendage formed with the body of this triangle.

[0071] The present invention is in no way limited to the embodiment described and represented, but a person skilled in the art will be able to make any variation in accordance with the invention.

[0072] Thus, it could be predicted that the upper suspension triangle 2 is equipped with an aerodynamic appendage and that these two elements are formed by an additive process.

[0073] In another variant of the invention, it could be provided that the walls forming the aerodynamic screen are not perforated in order to minimize the drag induced by the suspension triangles.

[0074] The invention also applies to a suspension arm which, unlike a suspension triangle, has only one point of attachment to the vehicle chassis.

Claims

1. Suspension support element (10) for a motor vehicle, such as a suspension arm or triangle, comprising a body (100) adapted to secure a wheel to a chassis of the motor vehicle, characterized in that it further comprises at least one aerodynamic appendage (200, 300) which is adapted to modify the airflow around said body (100) when the motor vehicle moves forward and which forms a single monobloc piece with said body (100).

2. Suspension support element (10) according to the preceding claim, wherein said at least one aerodynamic appendage (200, 300) is formed by a plate of thickness less than 3 millimeters.

3. Suspension support element (10) according to any one of the preceding claims, wherein said body (100) and each aerodynamic appendage (200, 300) are formed by additive manufacturing, preferably in the same material.

4. Suspension support element (10) according to any one of the preceding claims, wherein said at least one aerodynamic appendage (200, 300) comprises an air deflector, for example a cooling scoop (200) of a braking system of the motor vehicle.

5. Suspension support element (10) according to any one of the preceding claims, wherein said at least one aerodynamic appendage (200, 300) comprises at least one wall (310, 320) substantially flat and situated in a plane substantially parallel to the mean plane of the body (100).

6. Suspension support element (10) according to the preceding claim, in which said at least one wall (310, 320) has at least one opening (311, 321).

7. A method for manufacturing a suspension support element (10) for a motor vehicle, such as a suspension arm or triangle, comprising a body (100) adapted to secure a wheel to a chassis of the motor vehicle and at least one aerodynamic appendage (200, 300), said method being characterized in that it includes a simultaneous formation operation of said body (100) and of each aerodynamic appendage (200, 300).

8. Manufacturing method according to the preceding claim, wherein said body (100) and each aerodynamic appendage (200, 300) are formed by additive manufacturing.

9. Manufacturing method according to the preceding claim, wherein said body (100) extending in a mean plane, during the forming operation, the mean plane of said body (100) is inclined with respect to the vertical at an angle of less than 30 degrees.

10. A manufacturing method according to one of the two preceding claims, wherein, during the forming operation, supports which support said body (100) are simultaneously formed with said body (100) and wherein, after the forming operation, a finishing operation is provided during which the supports are cut from said body (100).