Lower cup for motor vehicle suspension bump stop

Abstract

The invention relates to a lower cup for a motor vehicle suspension bump stop, comprising a lower bearing section (1) on which a suspension spring is intended to bear and an upper section (2) for receiving an upper cup rotating relative to an axis. The lower cup comprises a rigid part (3) having a lower wall (4) forming the bottom (1a) of the bearing section (1) and a filtering element (8) having a lower bearing wall (9) on which the spring is intended to bear and an upper wall (10) for mounting the filtering element on the bottom. The lower cup further comprises a reinforcing insert (11) disposed at the interface between the bottom (1a) of the bearing section (1) and the upper wall (10) of the filtering element (8). Figure 3b

Description

Title of the invention: Lower cup for motor vehicle suspension stop

[0001] The invention relates to a lower cup for a suspension stop of a motor vehicle, as well as a method for manufacturing such a lower cup.

[0002] The invention applies in particular to a suspension stop comprising a fixed upper cup intended to be associated with the vehicle body and a rotating lower cup having an upper section for receiving the upper cup in relative rotation around an axis and a support section for the suspension spring.

[0003] In particular, lower cups are known which comprise a rigid part having a lower wall forming the bottom of the spring support section, and a filtering element which has an upper wall to allow the mounting of said filtering element on said bottom, and a lower wall on which the spring is intended to come directly to rest in order to filter the forces induced by the axial support of said spring on said support section.

[0004] In the case of stops intended to support heavy loads, it is also known to add a reinforcing insert in the bearing section of the rigid part and / or in the filtering element, in particular by overmolding, which proves complex to implement in order to keep said reinforcement in the mold.

[0005] The invention aims to improve the prior art by proposing a lower cup for a suspension stop having a spring support section which can support significant loads and whose manufacture is simplified.

[0006] To this end, according to a first aspect, the invention proposes a lower cup for a suspension stop of a motor vehicle, said lower cup comprising a lower support section on which a suspension spring is intended to bear and an upper section for receiving an upper cup in relative rotation about an axis, said lower cup comprising a rigid part having a lower wall forming the bottom of the support section and a filtering element having a lower support wall on which the spring is intended to bear and an upper wall for mounting said filtering element on said bottom, said lower cup further comprising a reinforcing insert which is disposed at the interface between the bottom of the support section and the upper wall of the filtering element.

[0007] According to a second aspect, the invention proposes a method for manufacturing such a lower cup, which successively provides for forming the rigid part, mounting the reinforcement insert against the bottom of the support section and then overmolding the insert onto said bottom by the filtration element.

[0008] Other features and advantages of the invention will become apparent from the following description, made with reference to the accompanying figures, in which:

[0009] [Fig-1] represents in perspective seen from below a rigid part of a lower cup according to an embodiment of the invention;

[0010] [Fig.2] represents in perspective view from below the rigid part of [Fig.1], on which has a reinforcing insert mounted on it;

[0011] [Fig.3] shows in perspective, viewed from below, a lower cup according to the invention.

[0012] [Fig.3a] and

[0013] [Fig.3b] being partial representations of said lower cup, along different axial cutting planes of the [Fig.3].

[0014] In relation to these figures, a lower cup for a motor vehicle suspension stop is described below, as well as a method for manufacturing such a lower cup.

[0015] The suspension stop is in particular intended to be integrated into a suspension leg of a motor vehicle, for example a telescopic leg of a steering wheel of said motor vehicle.

[0016] A suspension strut classically comprises a shock absorber, a suspension spring, and a suspension bump stop on which the spring rests, a wheel of a motor vehicle being mounted on the chassis by means of such a strut which allows the suspension of the body relative to the ground.

[0017] The suspension stop comprises a fixed upper cup intended to be associated with the vehicle body, in particular via a filter block, and a rotating lower cup, said cups forming with each other an interface of relative rotation around an axis A.

[0018] In this description, the terms for positioning in space are taken with reference to the axis A of relative rotation of the cups (vertical in the figures). In particular: - the terms "interior" and "exterior" are relative to a disposition respectively close to and at a distance from this axis A; - The terms "axial" and "radial" refer to an arrangement respectively along this axis A and moving away from or towards it.

[0019] Furthermore, the terms "upper" or "above" and "lower" or "below" refer to the arrangement of the stop as shown in reverse in Figures 1 to 3.

[0020] In a known manner, the rotation interface may include rolling bodies which are arranged between the cups in order to allow their relative rotation around the axis A. To do this, the upper and lower cups may each include a washer, in particular made of stamped sheet metal, forming between them the rotation interface, each of said washers being provided with a lower and upper respectively bearing track between which the rolling bodies are arranged.

[0021] Alternatively, the cups can be mounted in relative rotation in a smooth manner, with or without the interposition of a friction washer in the rotation interface.

[0022] The lower cup has a lower support section 1, on which an upper coil of the suspension spring is intended to bear axially, and an upper section 2 for receiving the upper cup, in relative rotation around the axis A.

[0023] Thus, when the spring is subjected to compression and rebound, the winding of its coils is modified, which causes the lower cup to rotate. Furthermore, turning the wheels also induces a rotation of the lower cup.

[0024] The cups allow, in particular, the absorption of the forces from the spring and possibly those from the shock absorber. To this end, the cups comprise a part 3 made of a sufficiently rigid material, in particular a thermoplastic material, for example of the polyamide type, preferably polyamide 6.6, possibly reinforced with glass fibers.

[0025] Advantageously, the parts 3 can be made by molding, in particular in thermoplastic material as described above, in order to facilitate their manufacture, and thus reduce the overall production costs of the suspension stop.

[0026] In relation to the figures, the rigid part 3 has a lower wall 4 forming the bottom la of the support section 1, as well as the upper section 2 for mounting the upper cup, said bottom and said upper section being formed as a single piece during the molding of said rigid part.

[0027] In the embodiment shown, the bottom of the support section 1 has an axial sleeve 5, around which the upper coil of the spring is intended to be wound, as well as a radial annular bearing surface 6 which extends externally, and against the axial face of which said upper coil comes to rest.

[0028] In particular, the base has a curved inner bearing surface 7 for connecting the sleeve 5 to the outer radial bearing surface 6, said inner bearing surface preferably having a radius of curvature substantially equal to the radius of curvature of the coil upper, in order to allow said coil to conform to said inner bearing when winding around sleeve 5.

[0029] The rigid part 3 further comprises a filtering element 8 which is attached to the bottom of the support section 1, in order to filter the forces induced by the axial support of the spring on said support section and to improve the distribution of the forces induced by said support. For this purpose, the filtering element 8 may be made of a material that is more flexible than the material forming the rigid part 3, in particular by being made of an elastomeric material, for example of the TPU or TPE type.

[0030] The filter element 8 has a lower support wall 9, on which the spring is intended to bear, and an upper mounting wall 10 of said filter element on the bottom la.

[0031] In particular, as shown in Figures 3, 3a and 3b, the filtration element 8 comprises: - an outer radial ring 8a covering the radial span 6; - an axial inner skirt 8b externally covering the sleeve 5 of the rigid part 3; and - an intermediate ring 8c for connecting said skirt to the outer ring 8a;

[0032] the lower wall 9 supporting the spring and upper wall 10 mounting on the base each extending over the respective lower and upper faces of said crowns 8a, 8c and of said skirt 8b.

[0033] The lower cup further includes a reinforcing insert 11 which is positioned at the interface between the bottom of the support section 1 and the upper wall 10 of the filter element 8. This optimizes the absorption of axial forces exerted by the spring 1, particularly in the case of significant axial loads, and also ensures good stability of the filter element on the bottom, especially with regard to the risk of deflection under load. In particular, the reinforcement of the rigid part 3 and the filter element 8 is achieved by means of a single insert 11 which is simply mounted during the manufacture of the lower cup.

[0034] Advantageously, the filter element 8 is obtained by molding, the reinforcing insert 11 being overmolded by said filter element on the bottom la of the support section 1.

[0035] In particular, the lower cup can be manufactured according to a process which successively involves: - to form the rigid part 3, in particular by molding a thermoplastic material as described above ([Fig. 1]); then - mount the reinforcing insert 11 against the bottom of the support section 1 of said rigid part ([Fig.2]); then - overmolding the insert 11 onto said base by means of the fixing element 8 ([Fig.3]).

[0036] In the embodiment shown, the reinforcing insert 11 is formed from a metal sheet which is shaped to the geometry of the base of the support section 1, in particular by stamping.

[0037] Thus, the reinforcement insert 11 has an external radial portion 1la and an internal axial portion 11b connected by an intermediate curved portion 1le, said radial portion and said axial portion being arranged to be mounted opposite respectively the radial span 6 and the axial sleeve 5 of the bottom la, being connected by the curved portion 11c which comes opposite the corresponding span 7 of said bottom.

[0038] The reinforcing insert 11 has an upper wall 12 which is mounted against the bottom la of the support section 1, in particular by press fitting. In particular, the upper wall 12 extends over all the constituent parts of the insert 11, namely the inner axial portion 11b, the intermediate curved portion 1 le and the outer radial portion lia.

[0039] According to one embodiment, the base and / or the upper wall 12 have geometric means to ensure the retention of their assembly.

[0040] For this purpose, as shown in the figures, the bottom la of the support section 1 has raised slots 13 which are angularly separated, each extending over the sleeve 5, the curved wall 7 and the outer span 6, at least the axial portion 13a of each slot 13 being inscribed in an outer diameter which is substantially equal to the inner diameter of the upper wall portion 12 formed on the axial portion 11b, in order to allow mounting of the insert 11 on the bottom la by axial fitting of said skirt onto said slots.

[0041] In general, the reinforcement insert 11 and / or the rigid part 3 may include geometric means to ensure their assembly, and thus guarantee good cohesion before and during overmolding by the filtering element 8. Thus, the reinforcement insert 11 may for example include tabs formed on the periphery of the lower edge of its axial portion 11b, said tabs being intended to be folded over the inside of the sleeve 5 after assembly of said reinforcement insert on the bottom la.

[0042] After mounting the reinforcement insert 11 on the bottom la, the filtration element 8 is therefore overmolded onto said insert to finalize the manufacture of the support section 1.

[0043] Advantageously, the reinforcing insert 11 has through holes 14, particularly formed on its outer radial portion 1la, in which the material of the filter element 8 is disposed, especially during its overmolding onto said insert. This arrangement optimizes the attachment of the filter element 8 to the base la by anchoring said element in the insert 11. Furthermore, the holes 14 can contribute to the proper filling of the gaps left between each slot 13 during the overmolding operation.

Claims

Demands

1. Lower cup for suspension stop of motor vehicle, said lower cup comprising a lower bearing section (1) on which a suspension spring is intended to bear and an upper section (2) for receiving an upper cup in relative rotation about an axis (A), said lower cup comprising a rigid part (3) having a lower wall (4) forming the bottom (la) of the bearing section (1) and a filtering element (8) having a lower bearing wall (9) on which the spring is intended to bear and an upper wall (10) for mounting said filtering element on said bottom, said lower cup being characterized in that it further comprises a reinforcing insert (11) which is disposed at the interface between the bottom (la) of the bearing section (1) and the upper wall (10) of the filtering element (8).

2. Lower cup according to claim 1, characterized in that the reinforcing insert (11) is formed of a metal sheet conforming to the geometry of the bottom (la) of the support section (1).

3. Lower cup according to one of claims 1 or 2, characterized in that the reinforcing insert (11) has through holes (14) in which the material of the filtering element (8) is disposed.

4. Lower cup according to any one of claims 1 to 3, characterized in that the bottom (la) of the support section (1) has raised crenellations (13) which are angularly separated.

5. Lower cup according to any one of claims 1 to 4, characterized in that the bottom (la) of the bearing section (1) has an axial sleeve (5) and a curved inner bearing surface (7) for connecting said sleeve to a radial bearing surface (6) which extends outwards.

6. Lower cup according to claims 4 and 5, characterized in that the through holes (14) are formed in a radial portion (1la) of the reinforcing insert (11).

7. Lower cup according to any one of claims 1 to 6, characterized in that the filtering element (8) is made from a material which is more flexible than the material forming the rigid part (3).

8. Lower cup according to claim 7, characterized in that the filtering element (8) is made from an elastomeric material for example of the TPU or TPE type, the lower cup being made from a thermoplastic material for example of the polyamide type, optionally filled with glass fibers.

9. Lower cup according to any one of claims 1 to 8, characterized in that the reinforcing insert (11) has an upper wall (12) which is mounted against the bottom (la) of the bearing section (1).

10. Lower cup according to claim 9, characterized in that the bottom (la) of the bearing section (1) and / or the upper wall (12) of the reinforcing insert (11) has geometric means (13) for retaining their assembly.

11. Lower cup according to any one of claims 1 to 10, characterized in that the filter element (8) is obtained by molding, the reinforcing insert (11) being overmolded by said filter element on the bottom (la) of the support section (1).

12. Method of manufacturing a lower cup according to claim 11, characterized in that it successively provides for forming the rigid part (3), mounting the reinforcing insert (11) against the bottom (la) of the support section (1) and then overmolding the insert (11) onto said bottom by the filtering element (8).

Images