Adaptable torsional axle structure

Abstract

The invention relates to a torsional axle structure (10) comprising: two suspension arms (12, 14) each having a front end adapted to be rotationally mounted on a chassis and an opposite rear end adapted to receive a wheel support; a cross member (15) having two transverse ends (28, 30) opposite each other with respect to a median zone (32), and two connecting members (16, 18) adapted to cooperate respectively with said transverse ends and said arms to connect together said two suspension arms (12, 14) parallel to each other. The two connecting members (16, 18) each have a notched end (58), and they are adapted to be connected respectively to the two transverse ends (28, 30) of the cross member, while the notched ends (58) of the two connecting members receive respectively the intermediate zones (25, 27) of the suspension arms.Figure to be published with the abbreviation: Fig. 1.

Description

Title of the invention: Adaptable torsional axle structure

[0001] The present invention relates to a torsional axle structure for a motor vehicle.

[0002] Known torsional axle structures include two suspension arms, a left arm and a right arm, each having a front end pivotally mounted under the chassis of the motor vehicle and an opposite rear end adapted to receive a wheel support. The two suspension arms are connected to each other by a cross member.

[0003] These torsional axle structures are relatively compact and lightweight, so they are usually implemented on entry-level vehicles.

[0004] On the other hand, the cross members are subjected to high stresses during vehicle movement and to large amplitude deformations in order to control oscillations in side slope as well as camber and steering movements induced by this side slope.

[0005] The cross members are usually open profiles whose two ends are notched to form seats suitable for receiving the suspension arms. In other words, the two notched ends conform to the contours of the arms. Furthermore, the ends of the cross member and the arms are welded together, and the connection is generally completed by a connecting element, or gusset, itself welded to both the end of the cross member and the arm.

[0006] Reference may be made to document WO2016 / 061078, which describes such a torsional axle structure.

[0007] However, when the axle is likely to support a significant mass, and the need for anti-roll stiffness is low, the axle stiffness at the junction of the cross member with the arms must be greater, and not necessarily as great in the middle area of ​​the cross member.

[0008] Also, a problem which arises and which the present invention aims to solve is to provide a torsional axle structure whose rigidity between the middle zone of the cross member and the arms can be adapted according to the type of vehicle.

[0009] In order to solve this problem, a torsional axle structure for a motor vehicle is proposed according to a first object, comprising: two suspension arms, each having a front end adapted to be rotationally mounted on a motor vehicle chassis and a rear end opposite said front end with respect to an intermediate zone and adapted to receive a wheel support; a cross member having two transverse ends opposite each other with respect to a median zone, and two connecting members adapted to cooperate respect tively with the said transverse ends of the said cross member and the intermediate areas of the said arms to connect together the said two suspension arms parallel to each other.

[0010] Also, said two connecting members each have a notched end, and said two connecting members are adapted to be connected respectively to said two transverse ends of said cross member, while the notched ends of said two connecting members receive respectively the intermediate zones of said suspension arms.

[0011] Thus, a feature of the invention lies in the use of connecting pieces, or gussets, which provide the essential connection to the arms, while the crossmember is essentially fixed to the connecting pieces. In this way, it is easy to adjust the axle's rigidity at the junction between the crossmember and the arms by choosing a connecting element with a wall of varying thickness and length. Furthermore, by choosing a longer connecting element, the rigidity of the crossmember's transverse end is locally increased.

[0012] Therefore, the cross member contributes essentially to the anti-roll stiffness and to the steering induced by roll, while the connecting parts provide the main connection with the arms.

[0013] According to the invention, said two connecting members and said cross member are advantageously U-shaped, and said transverse ends are respectively embedded inside said connecting members.

[0014] Thus, the cross member is an open, U-shaped cross member. It is therefore easy to produce it by stamping a metal strip. The two connecting members are also easily produced by stamping a metal plate. Furthermore, the two connecting members have a width significantly greater than that of the transverse ends of the cross member so that they can be perfectly fitted inside, as will be explained in more detail later in the description.

[0015] According to the invention, said cross member comprises a first bottom wall and two opposing first flanges, and said first bottom wall curves as one moves away from said median zone, while the height of said first two flanges decreases. Consequently, the quantity of material of the cross member decreases as one approaches its transverse ends.

[0016] Also, according to the invention, the first two wings have two free edges folded back on opposite sides. In this way, the edge of the wings is significantly stiffened. Moreover, the folded edges provide support for the connecting parts, as will be explained in more detail below.

[0017] Thus, the folded edges extend substantially along straight lines. Consequently, the first bottom wall curves as one moves away from the area median of the crossbar and as one approaches the transverse ends, converge towards the folded edges.

[0018] Also, according to the invention, said first base wall has two opposing free ends adapted to join respectively the two intermediate zones of said two suspension arms. The first base wall has an outer face and, opposite it, an inner face, which meet at the opposing free ends. As will be explained below, the outer face of the base wall rests against the intermediate zones of the arms precisely in the vicinity of the free ends.

[0019] Furthermore, according to the invention, said two connecting members each comprise a second bottom wall and two opposing second wings, each having a notch to form said notched end. The notches are parallel to the ends of the two second wings. They are preferably semicircular in shape and extend along the entire height of the second wings to the second bottom. The second bottom then defines a free projecting transverse edge. This free projecting transverse edge is adapted to bear against the arm in the intermediate zone and in a portion diametrically opposite to that in which the outer face of the first bottom wall bears. In this way, the arms are perfectly fixed to the cross member.

[0020] Advantageously, according to the invention, said two connecting members are respectively joined to said two transverse ends, and the notched ends to said suspension arms, by welding. Furthermore, the welding of the connecting members is done from the outside. And there is no need to weld the cross member from the inside, where access to the joint with a welding torch is difficult.

[0021] In accordance with the invention, and according to a first particularly advantageous embodiment, the axle structure further comprises two first shock absorber cups connecting said two suspension arms and said two connecting members respectively. The two shock absorber cups are welded between the portion of the arm extending to the wheel support and the crossmember. In this way, the crossmember is also squared with the arms.

[0022] According to a second embodiment of the invention, the axle structure further comprises two second shock absorber cups connecting said two suspension arms and said two opposite transverse ends, respectively. Squareness is thus achieved between the connecting pieces and the arms.

[0023] According to a second object, a motor vehicle is proposed comprising an axle structure as described above.

[0024] Other features and advantages of the invention will become apparent from the following description of particular embodiments of the invention, given as indicative but not exhaustive, with reference to the attached drawings on which:

[0025] [Fig.1] is a schematic three-quarter rear left perspective view of a torsional axle structure according to the invention;

[0026] [Fig.2] is a schematic view from below of the torsional axle structure such that represented on [Fig.1];

[0027] [Fig.3] is a partial schematic cross-sectional view of the object of [Fig.1] according to the Plan III - III and in accordance with a first method of implementation; and,

[0028] [Fig.4] is a partial schematic cross-sectional view of the object of [Fig.1] according to the plan III - III and in accordance with a second method of implementation.

[0029] Fig. 1 shows a rear torsion axle structure 10, adapted to be installed under the chassis of a motor vehicle. It is shown here in a motor vehicle seen from the left rear three-quarters view, and it is inscribed in an orthogonal coordinate system X, Y, Z, in which the X axis extends along a front-to-rear longitudinal direction of the motor vehicle, oriented towards the rear; the Y axis extends along a transverse direction of the vehicle, oriented from left to right when in motion; and the Z axis extends along a vertical direction, oriented away from the ground.

[0030] Thus, the torsional axle structure 10 comprises a left rear arm 12 and a right rear arm 14 opposed to each other and held together along a longitudinal component X by a cross member 15 and, respectively, by a left connecting member 16 and a right connecting member 18.

[0031] Also, the torsional axle structure 10 has a left part 20 symmetrical to a right part 22 with respect to a median plane Pm.

[0032] The arms 12, 14 each have a front end equipped with a socket 24 so that they can be pivotally mounted under the chassis of the motor vehicle by means of, for example, a "silent block".

[0033] And on the opposite side, the rear end of the arms 12, 14 is equipped with a wheel support 26. Between their two ends, the arms 12, 14 respectively have an intermediate left zone 25 which is joined, on its inner side, by the left connecting member 16, and an intermediate right zone 27 which is also joined on its inner side by the right connecting member 18. Also, the arms 12, 14 are hollow, and they have a substantially circular cross-section at the intermediate zones 25, 27.

[0034] As regards the cross member 15, it has two opposite transverse ends, a left transverse end 28 and a right transverse end 30. These two transverse ends 28, 30 are symmetrical to each other with respect to a median zone 32 which is cut by the average plane Pm.

[0035] The cross member 15 is U-shaped and comprises, on the one hand, a first bottom wall 34 having an outer face 35 and bottom openings 36, and on the other hand, two first opposing wings 38, 40. These have wing openings 42. These openings 36, 42 make it possible to significantly lighten the crossbeam, without weakening it.

[0036] Also, it will be observed that the first bottom wall 34 curves as one moves away from the median zone 32 and as one approaches the two transverse ends 28, 30. In addition, as one moves away from the median zone 32, symmetrically, the height of the first two wings 38, 40 decreases.

[0037] Reference will now be made to [Fig. 2] showing the torsional axle structure 10 viewed from below. We thus find the cross member 15, with its first bottom wall 34, which has an inner face, and its first two opposing flanges 38, 40. We also find its two transverse ends, left 28 and right 30. Thus, the bottom wall 34 extends into the left transverse end 28 and terminates with a free left end 44, while in the right transverse end 30, it terminates with a free right end 46.

[0038] The free ends 44, 46, on the side of the outer face of the first bottom wall 34, are thus supported respectively under the left arms 12 and right arms 14 in the intermediate zones, left 25 and right 27.

[0039] It will also be observed that the two opposing wings 38, 40 have respectively a front edge 48 and a rear edge 50, which are folded back in opposite directions. Such folded edges 48, 50 serve, in particular, to stiffen the two opposing wings 38, 40.

[0040] We will refer again to [Fig.1] and then to [Fig.3], in order to describe in detail the connecting members 16, 18 and their mode of cooperation with respectively, the arms 12, 14 and the cross member 15.

[0041] Thus, as shown in [Fig.1], the left connecting member 16 is U-shaped and has a second bottom 52 and two opposing second wings 54, 56. In addition, it has a notched end 58 opposed to a straight end 60. The two second wings 54, 56 each have, at the notched end 58, a notch 62 of circular symmetry.

[0042] Also, it will be observed that the two second opposing wings 54, 56 of the connecting member 16 are separated from each other by a distance substantially greater than the distance separating the first two opposing wings 38, 40 so as to be able to cover the left transverse end 28 of the cross member 15. In other words, the transverse end 28 fits perfectly inside the connecting member 16.

[0043] Furthermore, the notches 62 formed in the two opposing second wings 54, 56, along their entire height, expose at the end of the second bottom 52, a free transverse edge 64 projecting outwards. Thus, the connecting member 16 not only engages with the left transverse end 28, but also, the intermediate zone 25 rests continuously in the notches 62, while the inner face of the second bottom 52 comes to rest at the level of the free transverse edge 64 on the top of the arm in the intermediate zone 25, opposite the free left end 44 of the first bottom wall 34.

[0044] We thus find on [Fig.3], in section, the connecting member 16 capping the left transverse end 28 of the cross member 15, and the intermediate zone 25 of the left arm 12 supported in the notch 62 of the second one 56.

[0045] Also, the free transverse border 64 is found resting on the top of the arm 12 at the level of the intermediate zone 25 and in a diametrically opposite position, the free left end 44 of the bottom wall 34, resting against the arm 12.

[0046] Thus, as illustrated in [Fig.1], the connecting member 16 is connected to the left transverse end 28 and to the left arm 12 by applying a weld bead to the external joint of the parts in contact.

[0047] Furthermore, the right connecting member 18 is identical to the left connecting member 16 and they are thus completely superimposable. In other words, the right connecting member 18 is connected to the right transverse end 30 of the cross member 15, which are themselves connected symmetrically in the right intermediate zone 27 of the right arm 14.

[0048] Furthermore, it will be observed that the torsional axle structure 10 comprises two shock absorber cups, a left shock absorber cup 66 and a right shock absorber cup 68. These shock absorber cups 66, 68 respectively have two front edges 70, 72 and two lateral edges 74, 76. They are respectively welded in the two opposite angles formed by the connecting pieces 16, 18 and the arms 12, 14.

[0049] Thus, on the left side, the front edge 70 of the cup 66 is welded against the second wing 54 of the left connecting member 16, while the lateral edge 74 is welded along the left arm 12.

[0050] On the opposite side, on the right side, the front edge 71 of the cup 68 is welded against the second wing of the right connecting member 18, while the lateral edge 74 is welded along the right arm 14.

[0051] In this way, the shock absorber cups 66, 68, in addition to their function of receiving the suspension springs in support, allow the connecting parts 16, 18 to be kept square with respect to the arms 12, 14 respectively.

[0052] According to another embodiment of the invention, not shown, the front edges 70, 72 of the shock absorber cup 66, 68 are welded onto the first wings of the cross member 15.

[0053] Thus, the two connecting pieces 16, 18 provide the essential connection with the arms 12, 14. Accordingly, the sheet metal thicknesses of the connecting pieces 16, 18 are chosen according to the rigidity required for the axle structure. This rigidity must be adapted primarily according to the stresses experienced by the axle structure, taking into account the masses involved and the wheel diameters.

[0054] In addition, and as illustrated in [Fig.4], shorter connecting pieces can also be chosen.

[0055] Elements analogous to those described above and playing the same role will bear on this [Fig.4] the same references affected by a prime sign: « ' ».

[0056] Thus, we find the connecting member 16' coming to cap the left transverse end 28' of the cross member 15', and the intermediate zone 25' of the left arm 12' supported in the notch 62' of the second wing 56'.

[0057] Also, we find the free transverse border 64' resting on the top of the arm 12' at the right of the intermediate zone 25' and in a diametrically opposite position, with respect to the free left end 44' of the bottom wall 34', resting against the arm 12'.

[0058] Thus, compared to the object in [Fig. 3], it is clear that the connecting member 16' is shorter. Consequently, the connection between the left transverse end 28' of the cross member 15', the left arm 12', and the connecting member 16' is less rigid. The right end of the axle structure obviously exhibits the same characteristics symmetrically.

[0059] Thus, with the same crossmember and suspension arms, the strength of the axle structure can be adapted according to the required use, for example a utility vehicle or a passenger vehicle.

Claims

Demands

1. Torsifiable axle structure (10) of a motor vehicle comprising: - two suspension arms (12, 14) each having a front end adapted to be rotationally mounted on a motor vehicle chassis and a rear end opposite said front end with respect to an intermediate zone (25, 27) and adapted to receive a wheel support; - a cross member (15) having two transverse ends (28, 30) opposite each other with respect to a median zone (32), and two connecting members (16, 18) adapted to cooperate respectively with said transverse ends of said cross member and the intermediate zones (25, 27) of said arms to connect together said two suspension arms (12, 14) parallel to each other;characterized in that said two connecting members (16, 18) each have a notched end (58), and in that said two connecting members (16, 18) are adapted to be connected respectively to said two transverse ends (28, 30) of said cross member, while the notched ends (58) of said two connecting members respectively receive the intermediate zones (25, 27) of said suspension arms.;

2. Torsible axle structure according to claim 1, characterized in that said two connecting members (16, 18) and said cross member (15) are U-shaped, and in that said transverse ends (28, 30) are respectively embedded inside said connecting members.

3. Torsible axle structure according to claim 2, characterized in that said cross member (15) comprises a first bottom wall (34) and two first opposing opposite wings (38, 40), and in that said first bottom wall (34) curves as one moves away from said median zone (32), while the height of said first two wings (38, 40) decreases.

4. Torsible axle structure according to claim 3, characterized in that said first two wings (38, 40) have two free edges (48, 50) folded back opposite each other

5. Torsible axle structure according to claim 3 or 4, characterized in that said first bottom wall (34) has two first opposing free ends (44) adapted to join respectively the two intermediate zones (25, 27) of said two suspension arms (12, 14).

6. Torsible axle structure according to any one of claims 2 to 5, characterized in that said two connecting members (16, 18) each comprise a second bottom wall (52) and two second opposite wings (54, 56) each having a notch (62) to form said notched end.

7. Torsible axle structure according to any one of claims 1 to 6, characterized in that said two connecting members (16, 18) are connected respectively to said two transverse ends (28, 30), and the notched ends (58) with said suspension arms (12, 14), by welding.

8. Torsible axle structure according to any one of claims 1 to 7, characterized in that it further comprises two first shock absorber cups (66, 68) respectively connecting said two suspension arms (12, 14) and said two connecting members (16, 18).

9. Torsible axle structure according to any one of claims 1 to 7, characterized in that it further comprises two second shock absorber cups connecting respectively said two suspension arms and said two opposite transverse ends.

10. Motor vehicle comprising an axle structure according to any one of claims 1 to 9.

Images