FR3083834A1 - STRUCTURE PIECE ASSEMBLY WITH BALL JOINT MECHANISM - Google Patents

Abstract

The invention relates to a structural part assembly (10) for a vehicle comprising a structural part (12) and a ball joint mechanism (14; 214), received in a housing (16) formed in the structural part ( 12). The ball joint mechanism (14) includes a ball head (20) and a ball seat (18) receiving the ball head (20). The ball joint seat (18) is received in the structural part (12). The structural part assembly (10) further comprises at least one skirt (36; 38) for protecting the interface (40) between the ball joint seat (18) and the structural part (12). The invention also relates to a suspension system for a vehicle comprising a suspension arm formed by such a set of structural parts.

Description

BALL JOINT STRUCTURE PIECE ASSEMBLY

Technical area

The present description relates to a set of structural parts for vehicles, comprising a structural part and at least one ball joint mechanism. The structural part may in particular be a connecting rod or a vehicle suspension arm.

Presentation of the prior art

In the automotive field, it is known to implement structural part assemblies comprising a structural part and at least one ball joint mechanism for articulating another part with respect to the structural part.

Such a set of structural parts is thus implemented, for example, as a suspension arm (or "link suspensions" or "control arm" in English) or a connecting rod provided with one or more ball joint mechanisms.

A suspension arm is associated with one or more ball joint mechanisms, each ball joint mechanism being received in a respective housing in the suspension arm. A ball joint mechanism allows, in known manner, a connection between the suspension arm and another part, retaining two degrees of freedom corresponding to two rotations along perpendicular axes, or even three degrees of freedom corresponding to three rotations along two perpendicular axes together.

A ball joint mechanism conventionally comprises a ball joint seat, integral with the suspension arm, and a ball joint head of generally spherical shape, intended to be secured to the other part. The ball head is received in a movable manner in the ball seat, along two or three perpendicular axes of rotation, two by two.

Conventionally, a suspension arm is metallic, most often made of steel or aluminum, while the ball joint mechanism and in particular the ball joint seat is made of steel.

However, to reduce the weight of motor vehicles, in particular in order to meet ever more stringent anti-pollution standards, it has been proposed to make the suspension arm in composite material loaded with carbon fibers, and the seat of the ball joint in aluminum. or aluminum alloy.

However, it was found that such a choice of materials did not ensure a satisfactory life of the ball joint mechanism.

Disclosure summary

The purpose of this description is in particular to present a vehicle structure part assembly having a longer service life compared to the existing one. Advantageously, the whole structural part is also of limited weight.

To this end, there is described a set of structural parts for a vehicle, in particular a set of connecting rods or vehicle suspension arms, comprising:

a structural part, in particular a connecting rod or a suspension arm, and a ball joint mechanism, received in a housing formed in the structural part, the ball joint mechanism comprising a ball joint head, a ball joint seat receiving the ball head ball joint, the ball joint seat being received in the structural part, the structural part assembly further comprising at least one skirt protecting the interface between the ball joint seat and the structural part.

Thus, the skirt prevents damage to the structural part in the vicinity of the ball joint seat. This also prevents deterioration of the ball joint seat, whether directly, due to possible projections of particles or stones on the ball joint seat, or indirectly, due to the deterioration of the structural part in the vicinity of the ball joint, which deterioration can lead, in some cases, to corrosion of the ball joint seat by oxidation.

In various particular embodiments, the whole structural part for a vehicle may in particular include one or more of the following characteristics, taken alone or in combination:

the ball joint seat is made of aluminum or aluminum alloy;

the structural part is made of composite material loaded with carbon fibers; the structural part assembly comprises at least one sealing bellows for sealing the interior of the ball joint seat where the ball head is received; each sealing bellows is fixed to the ball joint seat, in particular by means of a fixing ring tightening the sealing bellows against a crown formed on an end surface of the ball joint seat, or to the structural part;

the protective skirt is formed by the sealing bellows;

the sealing bellows and the protective skirt, if any, are made of polymer material, in particular chloroprene rubber;

the skirt is molded onto the assembly formed by the structural part and the ball joint mechanism;

the protective skirt is made of polymer material, in particular TPE, TP, TD;

the ball joint mechanism is of the ball joint type with threaded rod, the ball joint head being integral with a threaded rod;

the threaded rod is integral with a collar, the collar having a circumferential groove, the sealing bellows being tightened in the groove of the collar by a fixing ring;

the ball joint mechanism is of the hollow ball type, the ball head being formed by a hollow body defining a cylindrical through hole;

the hollow body has two cylindrical projections extending symmetrically from the ball head; and the structural part assembly comprising two sealing bellows, each projection has at its end opposite the ball head a circular groove, preferably made in a flange, a sealing bellows being tightened in each circular groove at by means of a fixing ring, each sealing bellows being moreover fixed on the ball joint seat.

Furthermore, a vehicle suspension system is described, intended to be interposed between the vehicle body and at least one vehicle wheel, the suspension system comprising:

- a rocket carrier intended to support a rocket carrying said at least one vehicle wheel;

- a suspension and damping device, functionally interposed between the vehicle body and the stub axle; and

- At least one suspension arm formed by a set of structural parts as described above in all its combinations, for directly or indirectly connecting the vehicle body to the stub axle.

Brief description of the drawings

Other characteristics and advantages of the structural part with a ball joint mechanism will appear on reading the following description of an exemplary embodiment, given by way of nonlimiting example, with reference to the attached drawings, in which:

- Figure 1 shows schematically in section, a first example of a structural part assembly with a ball joint mechanism for a motor vehicle;

- Figure 2 shows schematically in section, a second example of a structural part assembly with a ball joint mechanism for a motor vehicle;

- Figure 3 shows schematically in section, a third example of a structural part assembly with a ball joint mechanism for a motor vehicle; and

- Figure 4 schematically shows a suspension system for a motor vehicle comprising a suspension arm formed by a set of structural part with ball joint mechanism according to one of the examples of Figures 1 to 3.

Detailed description of exemplary embodiments

In the different figures, the same references designate identical or similar elements. For the sake of brevity in this description, only the differences between the embodiments are described in detail.

FIG. 1 represents a first example of a structural part assembly 10 for a motor vehicle.

The illustrated structural part assembly 10 essentially comprises a structural part 12 and a ball joint mechanism 14.

The structural part 12 has for example the shape of a connecting rod or a suspension arm.

By connecting rod, here is meant a structural part extending mainly along an axis, between two ends. A connecting rod can be substantially flat. A connecting rod has for example at each of its ends a housing 16 for receiving a ball joint mechanism 14.

Alternatively, the shape of the structural part 12, in particular a suspension arm for a vehicle, may be more complex than a connecting rod and / or may have a single housing for receiving a ball joint mechanism or more than two housing for receiving of a ball joint mechanism, in particular three housings for receiving a ball joint mechanism, in the case of a suspension triangle for example.

Advantageously, the structural part 12 is made of composite material loaded with carbon fibers. In particular, the composite material can be composed of a resin of polymeric material, electrically insulating, in which carbon fibers are embedded. A rigid structural part 12 is thus obtained which has a limited weight.

The ball joint mechanism 14, as illustrated, comprises - here consists of - a ball joint seat 18, a ball joint head 20 and two sealing bellows 22, 24 preventing in particular the ingress of water or solid particles inside the ball joint seat 18 where the ball head 20 is received.

The ball joint seat 18 has here an overall annular shape, of axis A normal to the plane of the structural part 12. The interior part of the ball joint seat 18 has a concave shape, of concavity adapted to the convexity of the ball head 20.

On each end surface 18a, 18b, the ball joint seat 18 has a crown 26a, 26b, projecting, forming, in section, a corner radially outside the crown 26a, 26b.

The ball joint seat 18 is for example force fitted into the housing 16 of the structural part 12 provided for receiving the ball joint mechanism 14. Other means of fixing the ball joint mechanism 14 to the structural part are however accessible to one skilled in the art.

Furthermore, the ball joint mechanism 14 here being of the “hollow ball joint” type, the ball head 20 is formed on a hollow body 28 having a through hole 27 of substantially cylindrical shape. The hollow body 28 may for example be of cylindrical overall shape, having a convex bulge forming the ball head 20. Thus, by complementarity of shapes of the ball head 20 with the concave part of the ball seat 18, the hollow body 28 can pivot around at least two axes B, C perpendicular to the axis A normal to the plane of the structural part 12. Advantageously, the hollow body 18 can also pivot around the axis A, normal to the plane of the part structure 12.

More specifically, the hollow body 28 has in the example illustrated, in addition to the bulge forming the ball head 20, two cylindrical projections 28a, 28b extending symmetrically on either side of the ball head and having, at the level from their respective ends, a flange 29a, 29b.

The sealing bellows 22, 24 are provided to prevent the penetration of water and / or particles between the ball head 20 and the ball joint seat 18. Each sealing bellows is for example made of chloroprene rubber (or CR rubber ).

Each of the bellows 22, 24 is fixed to the hollow body 28 forming the ball head 20, on the one hand, and the ball joint seat 18, on the other hand.

To do this, here, the hollow body 28 has in the vicinity of each of its ends, in this case on the peripheral surface of their respective flange 29a, 29b, a circular groove 30a, 30b. Thus, each sealing bellows 22, 24 is enclosed within a respective groove 30a, 30b by means of a respective fixing ring 32a, 32b. Advantageously, the section of the groove 30a, 30b has a shape substantially complementary to the shape of the section of the associated fixing ring 32a, 32b, this in order to improve the fixing of the sealing bellows 22, 24 on the body hollow 28 forming the ball head 20. Here, for example, each fixing ring 32a, 32b is of substantially circular section, the associated groove 30a, 30b being of rounded section.

Furthermore, a second respective fixing ring 34a, 34b is used to enclose each sealing bellows 22, 24 against a respective crown 26a, 26b, formed on an end surface 18a, 18b of the articulation seat 18 Here, by way of example, each second fixing ring 34a, 34b is of square section.

The articulation seat 18 can in particular be made of aluminum or an aluminum alloy. This also makes it possible to produce a structural part assembly 10 of reduced weight.

The hollow body 28 forming the ball head 20 is made of metal, in particular steel.

Finally, remarkably, each sealing bellows 22, 24 has a section forming a skirt 36, 38 for protecting the interface 40 between the structural part 12 and the ball joint seat 18. To do this, this section forming protective skirt 36, 38 extends here in a substantially planar manner, covering the end surface 18a, 18b of the ball joint seat 18 as well as at least part, preferably only part, of the surface of the part of structure 12, in the vicinity of the interface 40 between the ball joint seat 18 and the structural part 12. Here, advantageously, the protective skirt 36, 38 is formed integrally with the sealing bellows 22, 24 respective. This presents an economy in manufacturing the protective skirt 36, 38. In addition, this allows the protective skirt 36, 38 to ensure sealing in the vicinity of the interface 40 between the ball joint seat 18 and the part. of structure 12, thus preventing the presence of water at the interface 40 between the ball joint seat 18 and the structural part 12. This thus limits, or even avoids the appearance of redox reaction between the material of the structural part 12 and the material of the ball joint seat 18, in particular when the structural part 12 is made of composite material loaded with carbon fibers and the ball joint seat 18 is made of aluminum or aluminum alloy.

The protective skirt 36, 38 also makes it possible to limit or even prevent damage to the ball joint seat 18 or to the structural part 12, in the vicinity of the ball joint seat 18. The protective effect of the protective skirt 36, 38 is reinforced by the fact that the protective skirt is made of elastomeric material.

In addition, when the structural part 12 is made of composite material loaded with carbon fibers, the protective skirt 36, 38 makes it possible to avoid the exposure of these carbon fibers, in the vicinity of the ball joint seat. , the protective skirt 36, 38 in particular prevents graveling from damaging the resin which coats the fibers, in the vicinity of the ball joint seat 18. However, it has been found that exposing these carbon fibers, in the vicinity of the ball joint seat 18 made of metal, in particular aluminum or aluminum alloy, led to premature deterioration of the ball joint seat 18 due to the appearance of corrosion by oxidation-reduction. In this case, the ball joint seat 18 dissolves due to the redox reaction which then appears. The presence of the protective skirt 36, 38, covering in particular the interface 40 between the structural part 12 and the ball joint seat 18, limits or even prevents this premature deterioration of the ball joint seat 18. This therefore ensures an increased service life of the structural part assembly 10.

FIG. 2 illustrates another example 100 of a structural part assembly.

This example of a structural part assembly 100 differs from the first example 10 essentially in that each protective skirt 36, 38 is here a separate part, separated in particular from the sealing bellows 22, 24. Such an embodiment of the skirt of protection 36, 38, produced in the form of a separate part, makes it possible to produce the skirt 36, 38 in a greater choice of materials. In this case, in particular, the protective skirt 36, 38 can be one of a thermoplastic elastomer material (TPE), a thermoplastic material (TP) and a thermosetting material (TD).

In addition, as visible in Figure 2, the protective skirt 36 is here substantially planar. However, the protective skirt 38 can also have any geometry adapted to its environment, in order to limit the size of the ball joint mechanism 14, when it is fixed to the ball joint mechanism 14 and / or the structural part 12 and / or to the geometry of the interface 40 between the structural part 12 and the articulation seat

18. In particular, the geometry of the protective skirt 38 can be adapted to best match the shape of the interface 40 between the structural part 12 and the ball joint seat 18 to prevent particles or stones from damaging the structure 12 in the vicinity of the interface 40 and / or that water is present at this interface 40. Thus, in the example illustrated in FIG. 2, the protective skirt 38 has a section substantially in an "L" shape, having two branches 381, 382 such that the first branch 38i forms the protective part of the interface 40 between the structural part 12 and the ball joint seat 18, while the second branch 382 here extends perpendicular to the first branch 381 and covers the fixing ring 34b of the sealing bellows 24 on the ball joint seat 18.

Other geometries of the protective skirt are accessible to those skilled in the art.

Finally, FIG. 3 illustrates a third example 200 of a structural part assembly. This third example 200 differs essentially from the first example 10 in that it does not comprise a ball joint mechanism 14 of the hollow ball type like the first example, but a ball joint mechanism 214 with a threaded rod.

Thus, the ball-and-socket ball joint mechanism 214 comprises a ball-head 20 carried by a threaded rod 202, the ball-head 20 being at one end of the threaded rod 202. It should be noted that the threaded rod 202 can only have a thread over part of its length. The ball head 20 is here substantially spherical. The threaded rod 202 includes a flange 28 like that described with reference to the first example of a structural part assembly 10.

The threaded rod 202 projects from the ball joint seat 18 by a single face of the ball joint seat 18. Thus, the ball joint mechanism 214 of FIG. 3 comprises a single sealing bellows 22.

The ball joint seat 18 has a cylindrical outer shape, having a solid end 18b, opposite the end 18a from which the threaded rod 202 projects. The ball joint seat 18 nevertheless forms a housing for receiving the ball head 20 defined by an internal wall of the ball joint seat 18 of shape substantially complementary to the shape of the ball head 20 of FIG. 3.

In this case also, a protective skirt 38 is advantageously provided on the end surface 18b, full, of the ball seat 18, which protects in particular the interface 40 between the end seat 18 and the structural part 12. Here, the protective skirt 38 can for example be molded onto the assembly formed by the structural part 12 and the ball joint seat 18.

FIG. 4 illustrates a suspension system for vehicle 300, in particular for a motor vehicle, using a suspension arm formed by a set of structural parts 10, 100, 200 as illustrated in one of FIGS. 1 to 3 .

In known manner, such a suspension system 300 is intended to be interposed between the body of the vehicle 302 and at least one wheel of the vehicle 304. The suspension system essentially comprises:

a rocket carrier 306 intended to support a rocket 308 carrying said at least one wheel of the vehicle 304;

- A suspension and damping device 310, functionally interposed between the body of the vehicle 302 and the stub axle 306; and

at least one suspension arm formed by a set of structural parts 10, 100, 200 as described above in all of its combinations, for directly or indirectly connecting the body of the vehicle 302 to the stub axle carrier 306.

Such a suspension system 300 makes it possible to transmit the forces passing through the wheel 304, to the body of the vehicle 302. In such a system, the suspension arm (s) allows a vertical clearance to the wheel 304, making the suspension device and damping 310 functional, while limiting or even preventing transverse or longitudinal movement of the wheel 304 relative to the body 302.

The suspension and damping device 310 comprises for example a hydraulic damper and a return spring. The suspension and damping device 310 can be connected directly or indirectly to the body 302 and / or to the stub axle 306. One or more intermediate parts 312, 314 can be interposed each time between the suspension and damping device 310, on the one hand, and the body 302 or the rocket carrier 306, on the other hand.

Such a suspension system 300 may comprise more than one suspension arm associated with each wheel 304, in particular up to five suspension arms per wheel.

Each suspension arm takes the form, for example, of a connecting rod, comprising a ball joint mechanism in the vicinity of each of its ends, or of a suspension triangle then comprising from one to three ball joint mechanisms, which are not aligned.

Each suspension arm can be connected directly or indirectly to the body 302. For example, each suspension arm can be fixed to the body 302 by means of a cradle or a cross member 316 fixed to the body 302, or an intermediate connecting rod.

Similarly, each suspension arm can be fixed to the stub axle 306 directly or indirectly. For example, each suspension arm is connected to the stub axle 5 306 by means of an intermediate link.

Of course, the present disclosure is in no way limited to the exemplary embodiments described above, by way of nonlimiting illustration. On the contrary, many variants are accessible to those skilled in the art.

In particular, the characteristics of the various embodiments described 10 can be combined when they are not contradictory.

In addition, each sealing bellows is alternately attached to the structural part rather than to the ball joint seat. This is particularly interesting on the end surface 18b of the ball joint seat 18 of the example of FIG. 3, from where the threaded rod does not protrude. In this case, in fact, the fixing of the sealing bellows can be more easily carried out on the structural part directly, rather than on the ball joint seat. However, fixing the sealing bellows to the ball joint seat appears to be a more compact solution.

Claims (15)

1. A structural part assembly (10; 100; 200) for a vehicle, in particular a connecting rod or suspension arm assembly for a vehicle, comprising: a structural part (12), in particular a connecting rod or a suspension arm, and a ball joint mechanism (14; 214), received in a housing (16) formed in the structural part (12), the ball joint mechanism ( 14; 214) comprising a ball head (20), a ball seat (18) receiving the ball head (20), the ball seat (18) being received in the structural part (12), the assembly structural part (10; 100; 200) further comprising at least one skirt (36; 38) for protecting the interface (40) between the ball joint seat (18) and the structural part (12). 2. A structural part assembly according to claim 1, in which the ball joint seat (18) is made of aluminum or an aluminum alloy. 3. assembly of structural part according to claim 1 or 2, wherein the structural part (12) is made of composite material loaded with carbon fibers. 4. structural part assembly according to one of claims 1 to 3, comprising at least one sealing bellows (22; 24) for sealing the interior of the ball joint seat (18) where the ball head is received (20). 5. A structural part assembly according to claim 4, in which each sealing bellows (22, 24) is fixed to the ball joint seat (18), in particular by means of a fixing ring (34a; 34b) tightening the sealing bellows (22; 24) against a crown (26a; 26b) formed on an end surface (18a; 18b) of the ball joint seat (18), or on the structural part (12). 6. assembly of structural part according to claim 4 or 5, wherein the protective skirt (36; 38) is formed by the sealing bellows (22; 24). 7. assembly of structural part according to one of claims 4 to 6, wherein the sealing bellows (22; 24) and the protective skirt (36; 38), if any, are made of polymer material, especially in chloroprene rubber. 8. assembly of structural part according to any one of claims 1 to 5, wherein the skirt (36; 38) is molded onto the assembly formed by the structural part (12) and the ball joint mechanism (14; 214) . 9. assembly of structural part according to any one of claims 1 to 5, 8, wherein the protective skirt (36, 38) is made of polymeric material, in particular TPE, TP, TD. 10. A structural part assembly according to any one of the preceding claims, in which the ball joint mechanism (214) is of the ball joint type with threaded rod, the ball joint head (20) being integral with a threaded rod (202 ). 11. A structural part assembly according to claim 10, claim 4 applying, in which the threaded rod is integral with a collar (29a), the collar having a circumferential groove (30a), the sealing bellows ( 22) being clamped in the groove (30a) of the flange (29a) by a fixing ring (32a). 12. A structural part assembly according to any one of claims 1 to 9, in which the ball joint mechanism (14) is of the hollow ball type, the ball head (20) being formed by a hollow body (28) defining a cylindrical through hole (27). 13. A structural part assembly according to claim 12, in which the hollow body (28) has two cylindrical projections (28a; 28b) extending symmetrically from the ball head (20). 14. structural part assembly according to claim 13, the structural part assembly (10; 100) comprising two sealing bellows (22; 24), in which each projection (28a; 28b) has at its opposite end. at the ball head (20) a circular groove (30a; 30b), preferably made in a flange (29a; 29b), a sealing bellows (22; 24) being clamped in each circular groove (30a; 30b) by means of a fixing ring (32a; 32b), each sealing bellows (22; 24) being moreover fixed on the ball joint seat (18). 5 15. Suspension system (300) for a vehicle, intended to be interposed between the body of the vehicle (302) and at least one wheel of the vehicle (304), the suspension system (300) comprising: - a rocket carrier (306) intended to support a rocket (308) carrying said at least one vehicle wheel (304); 10 - a suspension and damping device (310), functionally interposed between the vehicle body (302) and the stub axle (306); and - at least one suspension arm formed by a set of structural parts (10; 100; 200) according to any one of the preceding claims, for directly or indirectly connecting the vehicle body (302) to the stub axle 15 (306).