"Elastic joint for connecting a ground connection element to a motor vehicle chassis"

Abstract

The invention relates to an elastic joint (14) of a motor vehicle comprising: - an outer ring (16) having a main axis (A); - an inner ring (20) mounted concentrically in the outer ring (16); - an elastic sleeve (22) interposed radially between the inner ring (20) and the outer ring (16), the elastic sleeve (22) comprising at least one deformable pad (28) which extends axially in projection relative to the outer ring (16); - a fixed orthogonal stop face (24) relative to the inner ring (20) and against an annular support area (30) of which the pads (28) are mounted axially clamped, characterized in that the stop face (24) comprises a peripheral rim (32) which extends axially in projection and which surrounds the support face (30) in order to prevent the pads (28) from creeping radially outwards. Figure 1

Description

Title of the invention: "Elastic joint for connecting a ground connection element to a motor vehicle chassis" TECHNICAL FIELD OF THE INVENTION

[0001] The invention relates to an elastic joint for connecting a ground connection element to a motor vehicle chassis. TECHNICAL BACKGROUND OF THE INVENTION

[0002] It is known to equip motor vehicles with ground connection elements which make it possible to establish a connection between a chassis of the vehicle and the terrain on which it is moving.

[0003] The ground connection elements include in particular elements ensuring the suspension of the vehicle. These elements make it possible to connect unsprung masses, in particular the wheels, to the suspended masses, in particular the chassis of the vehicle. Such ground connection elements include, for example, suspension arms, shock absorbers, etc.

[0004] The ground connection elements are generally mounted on the vehicle chassis by elastic joints which allow a determined movement between the ground connection elements and the chassis. This makes it possible to provide flexibility in the chassis ground connection in order to improve the suspension comfort of the vehicle.

[0005] This elastic articulation comprises an inner ring which is thus intended to be fixed to the chassis, for example by clamping between the two flanges of a yoke. It also comprises an outer ring which is fixed to the associated ground connection element, and it finally comprises an elastic sleeve which is interposed radially between the two rings to allow relative axial elastic displacement between the two rings.

[0006] Furthermore, to limit the amplitude of the axial movement of the chassis relative to the axle, it is known to equip the articulation with a stop face. This stop face is fixed to the inner ring of the articulation. It is arranged axially opposite an edge of the elastic sleeve with a saturation clearance determined when no axial stress is applied to the elastic member. The elastic sleeve is equipped with buffers which project axially relative to the rings and which ensure permanent contact between the elastic sleeve and the stop face.

[0007] The buffers allow shock absorption, vibration absorption and participation in the elastic return of the elastic joint to its resting state.

[0008] When an axial force is applied to the elastic joint, the buffers are crushed against the abutment face.

[0009] It has been observed that the repetition of the crushing and releasing phases of the buffers causes the elastomer material to end up radially outwards. With time and wear, the elastomer material becomes less elastic and the buffers tend to deform permanently by moving outwards. As a result, the free end of the buffers is no longer arranged opposite the stop face. The buffers are therefore no longer in permanent contact with the stop face and / or they can no longer effectively perform their function of filtering vibrations and damping shocks. BRIEF SUMMARY OF THE INVENTION

[0010] The present invention proposes an elastic articulation for connecting a ground connection element to a motor vehicle chassis comprising:

[0011] - an outer ring having a main axis and connected to the connecting element at ground ;

[0012] - an inner ring connected to the vehicle chassis and mounted concentrically in the outer ring;

[0013] - an elastic sleeve interposed radially between the inner ring and the outer ring outer, the elastic sleeve comprising at least one deformable pad which extends axially projecting relative to the outer ring;

[0014] - a stop face orthogonal to the main axis which is fixed relative to the ring internal and against an annular support zone of which the buffers are mounted axially tight,

[0015] characterized in that the stop face comprises a peripheral rim which extends axially in projection and which surrounds the support face in order to prevent the pads from creeping radially outwards.

[0016] According to another characteristic of the invention, the bearing zone of the abutment face extends radially inwards to the inner ring.

[0017] According to another characteristic of the invention, the peripheral rim forms a continuous ring which completely surrounds the support zone.

[0018] According to another characteristic of the invention, the peripheral rim forms a discontinuous ring having free notches.

[0019] According to another characteristic of the invention, the peripheral rim is perforated.

[0020] According to another characteristic of the invention, the abutment face is carried by a radial cup.

[0021] According to another characteristic of the invention, the cup is crossed by water evacuation orifices which open into the support zone of the abutment face.

[0022] According to another characteristic of the invention, the abutment face comprises an internal rim which is arranged concentrically inside the peripheral rim and which delimits the support zone radially inwards.

[0023] According to another characteristic of the invention, the internal rim connects the bearing face and a radial clamping face of the cup against the inner ring.

[0024] According to another characteristic of the invention, the outer ring has a radial collar at the axial end arranged close to the abutment face, the buffer being interposed axially between the collar and the abutment face. BRIEF DESCRIPTION OF THE FIGURES

[0025] Other characteristics and advantages of the invention will appear during the reading of the detailed description which follows for the understanding of which reference will be made to the appended drawings briefly described below.

[0026] [Fig. 1] is an axial sectional view which represents an elastic articulation which is produced according to the teachings of the invention and which connects a ground connection element to a motor vehicle chassis.

[0027] [Fig.2] is a perspective view showing the elastic joint of [Fig.l].

[0028] [Fig. 3] is a perspective view showing a cup of the elastic joint of [Fig. 1] according to a first embodiment of the invention.

[0029] [Fig.4] is a perspective view showing a cup of the elastic joint of [Fig.1] according to a second embodiment of the invention.

[0030] [Fig.5] is a perspective view showing a cup of the elastic joint of [Fig.l] according to a third embodiment of the invention. DETAILED DESCRIPTION OF THE FIGURES

[0031] In the remainder of the description, elements having an identical structure or similar functions will be designated by the same references.

[0032] In the remainder of the description, the following orientations will be adopted without limitation:

[0033] - axial which is parallel to the axis “A” of the elastic joint;

[0034] - radials which are orthogonal to the axis “A” of the articulation elastic and which radiate from said axis “A” from the inside, close to the axis “A”, towards the outside.

[0035] [Fig.l] shows very schematically a chassis 10 of a motor vehicle. An element 12 for connecting the motor vehicle to the ground is intended to be connected to the chassis 10 shown in [Fig.l] and is intended to receive.

[0036] The ground connection element 12 is for example a cradle intended to carry an engine of the vehicle and which is intended to be connected to the front wheels of the vehicle. Alternatively, the ground connection element 12 is an axle crossmember or a suspension arm.

[0037] In a known manner, the ground connection element 12 is connected to the chassis 10 by by means of an elastic joint 14 having a main axis “A”.

[0038] As shown in Figures 1 and 2, the elastic joint 14 comprises an outer tubular ring 16 with axis "A". Without limitation, the axis "A" is here oriented vertically. The outer ring 16 here comprises at its lower end a collar 18 which extends radially in projection.

[0039] The articulation 14 further comprises an inner tubular ring 20 concentric with the outer ring 40.

[0040] An elastic sleeve 22 is interposed radially between the inner ring 20 and the outer ring 16. The inner ring 20 is thus connected to the outer ring 16 by means of the elastic sleeve 22.

[0041] The elastic sleeve 22 is for example made of an elastomeric material. The elastic sleeve 22 allows the outer ring 16 to slide elastically in an axial direction relative to the inner ring 20. This makes it possible in particular to confer a certain flexibility to the connection between the chassis 10 and the ground connection element 12 by axial shear deformation of the elastic sleeve 22.

[0042] To limit the axial displacement of the outer ring 16 relative to the inner ring 20, it is known to equip the elastic joint 14 with a radial stop face 24. This radial stop face 24 is rigidly supported by a support element. The support element is here formed by a cup 26. The cup 26 here has a central orifice 27.

[0043] This radial abutment face 24 is intended to be arranged in a fixed manner relative to the inner ring 20. The radial abutment face 24 is here arranged in an axial position in which the abutment face 24 is arranged opposite the collar 18 of the outer ring 16 with a determined axial saturation clearance "Jl" when the elastic sleeve 22 is in an axially unstressed state.

[0044] Furthermore, the elastic sleeve 22 comprises at least one buffer 28 formed by at least one portion which extends axially projecting relative to the outer ring 16.

[0045] As shown in [Fig.2], the elastic sleeve 22 here comprises two buffers 28 diametrically opposed with respect to the axis “A”. Each buffer 28 has the shape of a ring segment.

[0046] Alternatively, the elastic sleeve 22 comprises a single annular buffer.

[0047] According to another variant, the elastic sleeve 22 comprises a plurality of buffers distributed regularly around the “A” axis.

[0048] Each buffer 28 is mounted axially clamped against an annular support zone 30 of the abutment face 24. More particularly, each buffer 28 is here interposed between the collar 18 and the abutment face 24.

[0049] According to an example arrangement illustrated in [Fig. 1], the inner ring 20 is fixedly mounted under the chassis 10. The axis “A” is here mounted substantially vertically. The inner ring 20 is in particular fixed by a screw 29, a rod of which is inserted inside the inner ring 20. The rod is also passed through the central orifice 27 of the cup 26. A head 31 of the screw is here arranged below the cup 26 to tighten it axially against a lower edge of the inner ring 20. The cup 26 has for this purpose a radial tightening face 35 which is crossed by the central orifice 27. The rod of the screw 29 is inserted into a fixing orifice of the chassis 10 and a free end of the screw 29 is screwed into a nut 33. Thus, the inner ring 20 and the cup 26 are tightened axially against the chassis between the head 31 and the nut 33.

[0050] The saturation clearance “J1” makes it possible to limit and dampen the axial displacement in one direction of the outer ring 16, and therefore of the ground connection element 12, relative to the inner ring 20, and therefore relative to the chassis 10.

[0051] According to the teachings of the invention, to ensure that each buffer 28 remains permanently in contact with the abutment face 24, the abutment face 24 comprises a peripheral rim 32 which extends axially projecting relative to the abutment face 24 in the direction of the outer ring 16. The rim 32 surrounds the bearing zone 30 of the abutment face 24. Thus, the rim 32 forms a barrier which prevents each buffer 28 from being pushed radially outwards.

[0052] In the example shown in [Fig.3], the peripheral rim 32 forms a continuous ring which completely surrounds the support zone 30.

[0053] The bearing zone 30 of the abutment face 24 here extends radially inwards to the inner ring 20. The abutment face 24 further comprises an inner rim 34 which is arranged concentrically inside the peripheral rim 32 and which delimits the bearing zone 30 radially inwards. The inner rim 34 extends axially towards the inner ring 20. Thus, the peripheral rim 32, the bearing zone 30 and the inner rim 34 delimit an annular cup.

[0054] The internal rim 34 here connects the stop face 24 with the clamping face 35 which is axially offset towards the inner ring 20 relative to the stop face 24.

[0055] The elastic joint 14 is likely to be exposed to water projections during use of the vehicle. When the axis “A” of the elastic joint 14 is intended to be arranged generally vertically and the cup 26 is intended to be arranged at the bottom of the elastic joint 14, the rim 32 risks retaining water thus projected. To prevent water from stagnating in the cup 26, the cup 26 is crossed by evacuation orifices 36 which open into the support zone of the abutment face 24.

[0056] In a variant of the invention shown in [Fig.4], the peripheral rim 32 forms a discontinuous ring having free crenellations 38. In this case, the crenellations can ensure water drainage. However, it is possible to retain the water drainage holes 36 in this variant embodiment.

[0057] According to another embodiment variant shown in [Fig.5], the peripheral rim 32 is continuous but it is perforated. The perforated holes 40 ensure the evacuation of water. It is however possible to retain the water evacuation orifices 36 in this embodiment variant.

Claims

Claims

1. Elastic joint (14) for connecting a ground connection element (12) to a motor vehicle chassis (10) comprising: - an outer ring (16) having a main axis (A) and connected to the ground connection element (12); - an inner ring (20) connected to the chassis (10) of the vehicle and mounted concentrically in the outer ring (16); - an elastic sleeve (22) interposed radially between the inner ring (20) and the outer ring (16), the elastic sleeve (22) comprising at least one deformable buffer (28) which extends axially in projection relative to the outer ring (16);- a stop face (24) orthogonal to the main axis (A) which is fixed relative to the inner ring (20) and against an annular support zone (30) in which the buffers (28) are mounted axially clamped, characterized in that the stop face (24) comprises a peripheral rim (32) which extends axially in projection and which surrounds the support face (30) in order to prevent the buffers (28) from being pushed radially outwards.;

2. Elastic joint (14) according to the preceding claim, characterized in that the support zone (30) of the stop face (24) extends radially inwards as far as the inner ring (20).

3. Elastic joint (14) according to any one of the preceding claims, characterized in that the peripheral rim (32) forms a continuous ring which completely surrounds the support zone (30).

4. Elastic joint (14) according to any one of claims 1 or 2, characterized in that the peripheral rim (32) forms a discontinuous ring having free notches (38).

5. Elastic joint (14) according to any one of the preceding claims, characterized in that the peripheral rim (32) is perforated.

6. Elastic joint (14) according to any one of the preceding claims, characterized in that the stop face (24) is carried by a radial cup (26).

7. Elastic joint (14) according to the preceding claim, characterized in that the cup (26) is crossed by water evacuation orifices (36) which open into the support zone (30) of the stop face (24).

8. Elastic joint (14) according to any one of the preceding claims, characterized in that the stop face (24) comprises an internal rim (34) which is arranged concentrically inside the peripheral rim (32) and which delimits radially inwards the support zone (30).

9. Elastic joint (14) according to the preceding claim, characterized in that the internal rim (34) connects the bearing face (24) and a radial face (35) for clamping the cup (26) against the internal ring (20).

10. Elastic joint (14) according to any one of the preceding claims, characterized in that the outer ring (16) has a radial collar (18) at the axial end arranged close to the stop face (24), the buffer (28) being interposed axially between the collar (18) and the stop face (24).

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