Adaptable twist axle structure

Abstract

The invention relates to a twistable axle structure (10) comprising: two suspension arms (12, 14) each having a front end adapted to be rotatably 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 one another 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 one another. Said two connecting members (16, 18) each have a notched end (58), and they are adapted to be connected respectively to said two transverse ends (28, 30) of said crossmember, while the notched ends (58) of said two connecting members respectively receive the intermediate zones (25, 27) of said suspension arms.Figure to be published with the abstract: Fig. 1.

Description

Title of the invention: Adaptable twistable axle structure

[0001] The present invention relates to a twistable axle structure of a motor vehicle.

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

[0003] These twistable axle structures are relatively compact and lightweight such that they are usually implemented on entry-level vehicles.

[0004] On the other hand, the sleepers are subjected to high stresses when the vehicle is moving and to large amplitude deformations in order to be able to control the oscillations on slopes as well as the camber and steering movements induced by this slope.

[0005] The crossmembers are usually open profiles whose two ends are notched to form seats capable of receiving the suspension arms. In other words, the two notched ends follow the contours of the arms. In addition, the ends of the crossmember and the arms are welded together and the connection is generally completed by a connecting member, or gusset, itself welded to both the end of the crossmember and the arm.

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

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

[0008] Also, a problem which arises and which the present invention aims to solve is to provide a twistable 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, there is proposed, according to a first object, a twistable axle structure for a motor vehicle comprising: two suspension arms each having a front end adapted to be rotatably 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 one another with respect to a median zone, and two connecting members adapted to cooperate respec tively with said transverse ends of said crossmember and the intermediate zones of said arms to connect together 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 crossmember, while the notched ends of said two connecting members respectively receive the intermediate zones of said suspension arms.

[0011] Thus, a characteristic of the invention lies in the implementation of connecting pieces, or gussets, which provide the essential part of the connection with the arms, while the cross member is essentially integral with the connecting pieces. In this way, it is easy to adapt the rigidity of the axle at the junction between the cross member and the arms by choosing a connecting member whose wall is more or less thick and also, which is more or less long. Also, by choosing a longer connecting member, the rigidity of the transverse end of the cross member is locally increased.

[0012] The crossmember therefore contributes primarily to anti-roll stiffness and roll-induced steering, while the connecting pieces provide the main connection to the arms.

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

[0014] Thus, the crosspiece is an open crosspiece, U-shaped. It is then easy to produce it by stamping a metal strip. The two connecting members are also easily produced by stamping a metal plate. Also, the two connecting members have a width substantially greater than that of the transverse ends of the crosspiece so as to be able to fit them perfectly inside as will be explained in more detail in the rest of the description.

[0015] According to the invention, said crosspiece comprises a first bottom wall and two first opposite wings, and said first bottom wall curves as one moves away from said middle zone, while the height of said two first wings decreases. Consequently, the quantity of material of the crosspiece decreases as one approaches its transverse ends.

[0016] Also, according to the invention, said first two wings have two free edges folded back opposite one another. In this way, the edge of the wings is substantially stiffened. In addition, the folded edges allow the connecting pieces to be supported as will be explained in more detail below.

[0017] Thus, the folded edges extend substantially along rectilinear lines. Therefore, the first bottom wall which curves as one moves away from the zone median of the crosspiece and as we approach the transverse ends, converging towards the folded edges.

[0018] Also, and according to the invention, said first bottom wall has two first opposite free ends adapted to join respectively the two intermediate zones of said two suspension arms. The first bottom wall has an outer face and, on the opposite side, an inner face, which join in the first opposite free ends. As will be explained below, the outer face of the bottom wall comes to bear against the intermediate zones of the arms precisely in the vicinity of the free ends.

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

[0020] And advantageously, according to the invention, said two connecting members are connected respectively to said two transverse ends, and the notched ends with said suspension arms, by welding. Also, the welding of the connecting parts is done from the outside. And there is no need to come and weld the crosspiece from the inside, where access to the joint with a welding torch is difficult.

[0021] According to the invention, and according to a first particularly advantageous embodiment, the axle structure further comprises two first shock absorber cups respectively connecting said two suspension arms and said two connecting members. The two shock absorber cups are welded between the arm portion 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 respectively connecting said two suspension arms and said two opposite transverse ends. The squaring thus takes place between the connecting parts and the arms.

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

[0024] Other features and advantages of the invention will emerge from reading the description given below of particular embodiments of the invention, given as a guide. indicative but not limiting, with reference to the attached drawings in which:

[0025] [Fig.l] is a schematic perspective view of three-quarters from the rear left of a twistable axle structure according to the invention;

[0026] [Fig.2] is a schematic bottom view of the twistable axle structure such that shown in [Fig.l];

[0027] [Fig.3] is a partial schematic sectional view of the object of [Fig.l] according to the plan III - III and in accordance with a first mode of implementation; and,

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

[0029] [Fig.l] 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, and it is inscribed in an orthogonal reference frame X, Y, Z, in which the X axis extends in a front-rear longitudinal direction of the motor vehicle, oriented towards the rear; the Y axis extends in a transverse direction of the vehicle, oriented from left to right when in a rolling situation; and the Z axis extends in a vertical direction, oriented away from the ground.

[0030] Thus, the twistable axle structure 10 comprises a left rear arm 12 and a right rear arm 14 opposite 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 twistable 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, for example, of a “silent block”.

[0033] And on the other hand, the rear end of the arms 12, 14 is equipped with a wheel support 26. Between their two ends, the arms 12, 14 have respectively a left intermediate zone 25 which is joined, on its inner side, by the left connecting member 16, and a right intermediate 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 section in line with the intermediate zones 25, 27.

[0034] As regards the crosspiece 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 intersected by the mean plane Pm.

[0035] The crosspiece 15 is U-shaped and it 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 opposite wings 38, 40. These have wing openings 42. These openings 36, 42 make it possible to significantly lighten the crosspiece, 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. Furthermore, as one moves away from the median zone 32, symmetrically, the height of the two first wings 38, 40 decreases.

[0037] We will now refer to [Fig. 2] showing the twistable axle structure 10 seen from below. We thus find the cross member 15, with its first bottom wall 34, which has an inner face, and its two first opposite wings 38, 40. We also find its two left 28 and right 30 transverse ends. Thus, the bottom wall 34 extends, in the left transverse end 28 and ends with a left free end 44, while in the right transverse end 30, it ends with a right free 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 12 and right 14 arms in the intermediate zones, left 25 and right 27.

[0039] Also, it will be observed that the two opposite wings 38, 40 respectively have a front edge 48 and a rear edge 50, which are folded back opposite one another. Such folded edges 48, 50 make it possible in particular to stiffen the two opposite wings 38, 40.

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

[0041] Thus, as shown in [Fig.l], the left connecting member 16 is U-shaped and it has a second bottom 52 and two second opposite wings 54, 56. In addition, it has a notched end 58 opposite a right 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 opposite wings 54, 56 of the connecting member 16 are spaced apart from each other by a distance substantially greater than the distance separating the two first opposite wings 38, 40 so as to be able to cover the left transverse end 28 of the crosspiece 15. In other words, the transverse end 28 fits perfectly inside the connecting member 16.

[0043] Furthermore, the notches 62 formed in the two second opposite wings 54, 56, over their entire height, release at the end of the second bottom 52, a free transverse edge 64 projecting. Thus, the connecting member 16 not only engages on the left transverse end 28, but also, the intermediate zone 25 comes to bear 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 left free end 44 of the first bottom wall 34.

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

[0045] Also, we find the free transverse edge 64 resting on the top of the arm 12 to the right of the intermediate zone 25 and in a diametrically opposite position, the left free end 44 of the bottom wall 34, resting against the arm 12.

[0046] Thus, as illustrated in [Fig.l], 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 outer joint of the contacting parts.

[0047] Furthermore, the right connecting member 18 is identical to the left connecting member 16 and are thus completely superimposable. In other words, the right connecting member 18 is connected to the right transverse end 30 of the crosspiece 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 twistable 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, make it possible to keep the connecting pieces 16, 18 at right angles 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 to the first wings of the crosspiece 15.

[0053] Thus, the two connecting pieces 16, 18 provide the essential part of the connection with the arms 12, 14. Therefore, sheet thicknesses for the connecting pieces 16, 18 are chosen according to the rigidity required for the axle structure. This rigidity must be adapted essentially according to the forces undergone 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 similar to those described above and playing the same role will bear on this [Fig.4], the same references assigned a prime sign: “'”.

[0056] Thus, we find the connecting member 16' covering the left transverse end 28' of the crosspiece 15', and the intermediate zone 25' of the left arm 12' resting in the notch 62' of the second wing 56'.

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

[0058] Thus, compared to the object of [Fig.3], it is clearly seen that the connecting member 16' is shorter. In this way, 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 has the same characteristics in a symmetrical manner.

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

Claims

Claims

1. A twistable axle structure (10) for a motor vehicle comprising: - two suspension arms (12, 14) each having a front end adapted to be rotatably 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 one another 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 one another;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 crossmember, while the notched ends (58) of said two connecting members respectively receive the intermediate zones (25, 27) of said suspension arms.;

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

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

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

6. A twistable 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 facing wings (54, 56) each having a notch (62) to form said notched end.

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

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

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