FR2778606A1 - SUSPENSION STOP DEVICE - Google Patents

Abstract

Suspension stop device of the type comprising a bearing 9 forming an axial stop arranged between a support cup 12 for a spring 11 and an elastic support block 3 integral with the vehicle body, the bearing 9 comprising an upper ring 13 in contact with the elastic support block 3, and a lower ring 14 in contact with the support cup 12 for the spring, said device having means for axially retaining the support cup 12 in order to constitute a unitary assembly, the upper ring 13 supporting a sealing member 20 provided with an active part cooperating with the support cup 12 for the spring. The active part of the sealing member ensures the axial retention of the support cup 12 for the spring relative to the stop.

Description

Suspension stop device.

  The invention relates to the field of suspension stops used, in particular, on motor vehicles in the legs of

  telescopic suspension of the steering wheels.

  The suspension stop is generally arranged in the upper part of the suspension strut, between a metal lower cup, also serving as a support seat for the suspension spring, and an elastic support block. The elastic support block is composed of metallic elements and elastomer and is integral with the vehicle body. The suspension spring is arranged around the rod of a shock-absorbing piston, the end of which, generally the rod end of the piston, is integral with the elastic support block. The suspension stop thus allows axial forces to be transmitted between the spring and the vehicle body while allowing a relative angular movement between the spring support cup, movable in rotation, and the fixed elastic support block integral with the body. . This relative angular movement can result from a deflection of the steering wheel and / or from the compression of the

suspension spring.

  It is important to facilitate the transport and assembly of the suspension stop with the surrounding parts and in particular with the

  metal cup forming support seat for the spring.

  To this end, document US-A-4 995 737 proposes to provide each of the rings of the suspension thrust bearing with a plastic cover. Each cover has axial retaining protrusions of the other cover and one of the two covers has hooks capable of cooperating with lights arranged in the lower cup. It is thus possible to constitute a non-removable assembly between the suspension stop and the lower cup, which facilitates the transport and handling operations of the stop / cup sub-assembly, the operations of mounting the sub-assembly in the suspension strut system. of the vehicle and the automation of at least part of these operations. However, such a device has certain drawbacks - it makes it necessary to use two plastic covers, thereby increasing the cost and the axial size of the assembly; - It requires an opening in a specific location of the lower cup to cooperate with the hook of the lower cover, hence an increase in cost, - during assembly, it is necessary to angularly orient the lower cover of the stop by compared to the opening of the cup, which complicates this operation and its possible automation, here again the

cost thereby increased.

  Document DE U 295 06 796 shows a suspension stop comprising a bearing with two metal rings, the lower ring being in contact with a lower plastic cover which also serves to support the spring, which excludes the possibility of using the support cup

  as a raceway for rolling elements.

  The present invention proposes to solve these problems by simple means, inexpensive and making it possible to reduce both the number of parts, the axial size, the costs and to simplify the

assembly process.

  The suspension stop device according to the invention is of the type comprising a bearing forming an axial stop disposed between a bearing cup for a spring and an elastic support block secured to the vehicle body. The bearing comprises an upper ring in contact with the elastic support block, and a lower ring in contact with the bearing cup. The device has means for axially retaining the support cup for the spring in order to constitute a unitary assembly, the upper ring supporting a sealing member provided with an active part cooperating with the support cup. The active part of the sealing member cooperating with the support cup for the spring ensures the axial retention of said support cup with respect to the stop. This constitutes a unitary stop-cup unit without part

  additional and without increasing the size.

  In one embodiment of the invention, the sealing member is fixed to the periphery of the upper ring. In one embodiment of the invention, the sealing member comprises an annular seal and a metallic annular envelope crimped on the upper ring and capable of holding the seal. In another embodiment of the invention, the sealing member comprises a one-piece annular seal provided

  means of attachment to the upper ring.

  Advantageously, the sealing member comprises a sealing lip cooperating with a bearing surface of the cup. This sealing lip can be prestressed axially on the bearing surface of the cup. In another embodiment of the invention, the sealing member comprises an annular radial portion disposed opposite an annular radial portion of the cup and forming a seal by narrow passage. The sealing member may include a metallic element fixed on the upper ring and extending opposite the cup. Advantageously, the cup and the lower ring are in one piece. This gives a particularly economical way of assembling the suspension stopper and the lower cup.

forming spring support seat.

  The invention will be better understood on studying the description

  detailed of some embodiments taken by way of nonlimiting examples and illustrated by the appended drawings, in which: FIG. 1 is a view in axial section of the upper part of a vehicle suspension system, including a conforming stop to the invention; Figure 2 is a half view in axial section of a suspension stop according to the invention; and Figures 3 to 5 show variants of the embodiment of

Figure 2.

  The shock absorber comprises a cylinder 1 in which can slide

  a piston whose rod 2 is linked by its upper end to a block

  elastic support 3. The elastic support block 3 is fixed to an element of the chassis 4 and comprises: - an internal connection element 5, produced in two parts 5a and b and on which the end of the rod 2 of the shock absorber piston by means of a nut 6, - an external connecting element 7 serving for securing with the chassis 4, - an upper cup 8 serving as a support seat for the thrust bearing 9, - a block of rubber 10 adhered to the surface of these three parts and forming a connection between them with vibration filtration. The external connecting element 7 is at one end fixed to the chassis 4, for example by screwing, and at the other end is disposed axially between the two parts 5a and 5b. The upper cup 8 is arranged axially at the level of the internal connecting element 5, but is

larger diameter.

  We also see the suspension spring 1 1 whose upper end is supported on a lower cup 12 which, in turn, is supported

  also on the thrust bearing 9.

  As best seen in Figure 2, the upper cup 8 comprises a cylindrical portion 8a extending downward, opposite the chassis 4, and a radial portion 8b extending inward, the assembly of the upper cup 8 being embedded in the elastic material used in the elastic support block 3 which offers, near said upper cup 8, a radial portion forming a bearing surface 16 and an axial surface 17 defined by an annular axial protuberance 18 in which

  is drowned the cylindrical portion 8a.

  The suspension stop 9 itself comprises an upper ring 13 and a lower ring 14 made of sheet metal, between which are

housed balls 15.

  The balls 15 of the thrust bearing 9 are held by a cage 19 made of synthetic material, which is extended on the inner side by a sealing lip 19a coming to rub on the lower ring 14, and by a lip 19b coming to rub on the upper ring 13. The upper ring 13 comprises a toroidal portion 13a forming a rolling track for the balls 15. This toroidal portion 13a is extended inwards and downwards by a cylindrical portion 13b in contact with the lip 19b, and towards the outside by a radial portion 13c in contact with the bearing surface 16 then by a cylindrical portion 13d directed downwards in contact with the axial bearing 17. A radial flange 13e extends outward from

  the free lower end of the cylindrical portion 13d.

  The lower ring 14 comprises a toroidal portion 14a forming a rolling track for the balls 15 and extending inward and downward by an additional toroidal portion 14b of opposite concavity and in shape agreement with the cup 12. The ring lower 14 and the spring 1 1 are in contact with the cup 12, on either side of a radial portion 12a which extends outwards beyond

of spring 11.

  On the radial rim 13e forming the periphery of the upper ring 13 is fixed a sealing member 20 preventing the introduction

  external elements between the upper ring 13 and the cup 12.

  The sealing member 20 comprises an annular metallic element 21 and a seal 22 made of flexible material, for example elastomer or natural rubber. The metal element 21 crimped on the periphery of the upper ring 13 after the installation of the seal 22, is U-shaped section with radial branches oriented inward with an upper radial branch 21 a in contact with the upper face of the radial rim 13e of the upper ring 13, a lower radial branch 21lb disposed under the radial portion 12a of the cup 12 and of bore slightly greater than the outside diameter of the latter, and a cylindrical bottom 21c

  joining the radial branches 21a and 21b.

  The seal 22 is disposed between the upper 21a and lower 21b branches of the metal element 21 in contact with the bottom 21c and extends between the rim 13e and the lower branch 21b, and surrounds

  radially the periphery of the radial portion 12a of the cup 12.

  The seal 22 further comprises a lip 23 coming from its bore 22a near the lower branch 21b and extending inwards and upwards until it comes into contact with the lower face of the radial portion 12a of the cup 12. Provision is made for the material constituting the seal 22 and the lip 23, although being flexible, to be rigid enough to hold the cup 12 and the upper ring 13 together, as well as the lower ring 14 and the balls 15 before

  mounting of this assembly between the elastic support block 3 and the spring 11.

  The lower branch 21b of the metallic element 21 makes it possible to ensure the axial retention of the joint 22. It is also possible to provide for the cylindrical bearing surface 17 of the elastic support block 3 to be of diameter very slightly less than that of the cylindrical portion 13d the outer ring 13, for exerting on said cylindrical portion 13d a slight prestress so that the elastic support block 3 and the upper ring 13 are capable of being held together during assembly. The embodiment illustrated in Figure 3 is similar to the previous one, except that the sealing member 20 is devoid of metallic element. The sealing member 20 is in one piece, the seal 22 being provided with an upwardly directed extension 24 which surrounds the periphery of the radial rim 13e and which is provided with a plurality of hooks 25 which radially protrude from the face upper radial rim 13e and thus ensure the axial retention of said sealing member on the upper ring 13. The hooks 25 are elastic and chamfered to be able to pass around the periphery of the radial rim 13e during assembly of the sealing member 20 and upper ring 13. Alternatively, the hooks can be replaced by a continuous bead forming

axial restraint.

  In the embodiment illustrated in FIG. 4, the sealing member 20 is also one piece but includes only a metallic element 26 crimped on the periphery of the upper ring 13 and of a shape substantially similar to that of the metallic element 21 of Figure 2, except that the lower radial branch 26b extends partially under the radial portion 12a of the lower cup 12 by forming a narrow passage with the latter, and ensuring the axial retention of said cup 12 relative to the upper ring 13. This

  variant is particularly economical.

  The embodiment of FIG. 5 is close to that of FIG. 2, except that the bearing cup 12 for the spring also serves as a lower ring for the balls 15 of the bearing 9. The cup 12 comprises from the edge internal of the radial portion 12a a toroidal portion 12b forming a lower ring. The cylindrical portion 13b of the upper ring 13 forms a narrow passage with the cup 12 near the toroidal portion 12b to seal the

  bearing 9. This version is again very economical.

  Thanks to the invention, an easy-to-handle suspension stop is obtained before mounting, which reduces the vehicle manufacturing costs. This stop also guarantees a satisfactory seal and does not

  contains only a small number of parts.

Claims (9)

  1. Suspension stop device of the type comprising a bearing (9) forming an axial stop disposed between a bearing cup (12) for a spring and an elastic support block (3) integral with the vehicle body, the bearing comprising an upper ring (13) in contact with the elastic support block, and a lower ring (14) in contact with the support cup for the spring, said device having means for axially retaining the support cup in view to constitute a unitary assembly, the upper ring supporting a sealing member (20) provided with an active part cooperating with the bearing cup for the spring, characterized in that the active part of the sealing member ensures the axial retention of the support cup for the spring with respect to stop.   2. Device according to claim 1, characterized in that   the sealing member is fixed to the periphery of the upper ring.   3. Device according to claim 1 or 2, characterized in that the sealing member comprises an annular seal (22) and a metallic annular envelope (21) crimped on the upper ring and   able to maintain said seal.   4. Device according to claim 1 or 2, characterized in that the sealing member comprises a one-piece annular seal provided with fastening means (25) with the upper ring.   5. Device according to any one of the claims   above, characterized in that the sealing member comprises   a sealing lip (23) cooperating with a bearing surface of the cup.   6. Device according to claim 5, characterized in that the sealing lip is prestressed axially on the bearing surface of the cup. 7. Device according to claim 1 or 2, characterized in that the sealing member comprises an annular radial portion (26b) disposed opposite an annular radial portion of the cup and   forming a tightness by narrow passage.   8. Device according to claim 7, characterized in that the sealing member comprises a metallic element (26) fixed on the   upper ring and extending opposite the cup.   9. Device according to any one of claims   previous, characterized in that the support cup for the spring and the lower ring are in one piece.