Suspension stop device with sealing gasket

Abstract

[Suspension stop device with sealing gasket] This suspension stop device (2) comprises a lower support cover (6), an upper support cover (4), and at least one bearing (8) disposed between said covers. The lower support cover (6) comprises an annular radial portion (32) which is at least partially hollowed out to allow a plurality of ribs (34) spaced circumferentially apart. The device (2) comprises a sealing gasket (10) which has a heel (36) overmolded onto the hollowed-out portion of said hollowed-out annular radial portion (32) and onto the ribs (34), and which has a sealing portion (38) supported by the heel (36) and extending towards the upper support cover (4). The distal end of said sealing portion (38) of the sealing joint (10) forms a dynamic annular seal with the upper support cover (4). Figure for the abbreviation: Fig. 2.

Description

Title of the invention: Suspension stop device with sealing gasket. Technical field of the invention

[0001] The present invention relates to the field of suspension stop devices used in particular for motor vehicles in the suspension struts of the steering wheels. Prior art

[0002] A suspension stop device generally comprises a bearing forming an axial stop and upper and lower covers forming a housing for the bearing rings and ensuring the interface between said rings and the surrounding elements.

[0003] The suspension bump stop device is located in the upper part of the suspension strut between a suspension spring and the vehicle body. The suspension spring is mounted around a damper piston rod, the end of which is connected to the vehicle body. The suspension spring, of the helical type, bears axially, either directly or indirectly, against the lower end of the suspension bump stop device.

[0004] The suspension stop device allows axial and radial forces to be transmitted between the suspension spring and the vehicle body while allowing a relative rotational movement between the lower hood and the upper hood resulting from a steering of the vehicle's steering wheels and / or the compression of the suspension spring.

[0005] Generally, the upper cover of the suspension stop device is provided with a plurality of hooks arranged on an external skirt and adapted to interfere diametrically with a plurality of hooks on the lower cover. The hooks on each cover are spaced from each other in the circumferential direction.

[0006] The hooks form retaining means for axially retaining the upper and lower covers relative to each other. These hooks also form narrow passages to limit the intrusion of polluting particles radially between the outer skirt of the upper cover and the lower cover.

[0007] However, such a suspension stop device is generally exposed to various types of pollution.

[0008] Indeed, polluting particles can easily infiltrate between the outer skirt of the upper cover and the lower cover, then be directed towards the bearing and be introduced inside the latter.

[0009] To remedy this drawback, it is known from patent application DE-AÏ -10 2020 201 404 (SKF) to provide an external sealing gasket fixed by pinching between the bearing and the lower cover of the suspension stop device and provided with at least one sealing lip cooperating with the upper cover.

[0010] The present invention aims to simplify the manufacture of this type of suspension stop devices. Summary of the invention

[0011] The invention relates to a suspension stop device comprising a lower support cover, an upper support cover, and at least one bearing disposed between said covers.

[0012] The lower support cover includes an annular radial portion which is at least partially hollowed out so as to leave a plurality of ribs spaced from each other in the circumferential direction.

[0013] The suspension stop device further includes a sealing joint which is provided with a heel overmolded on the hollowed part of said hollowed annular radial portion and on the ribs, and which is provided with a sealing portion supported by the heel and extending towards the upper support cover.

[0014] The distal end of said sealing portion of the sealing joint forms with the upper support cover a dynamic annular seal.

[0015] The annular radial portion of the lower support cover, leaving the plurality of ribs intact, improves the grip of the seal's heel on the lower support cover and facilitates the overmolding of the seal.

[0016] Overmolding the sealing gasket eliminates a step during the assembly of the stop device. Furthermore, it also eliminates the need for a packaging element for the sealing gasket, which is typically included in stop devices with a sealing gasket that is separated and then assembled onto one of the covers.

[0017] Furthermore, the provision of the ribs makes it possible to further improve the bonding between the overmolded sealing gasket and the lower support cover, particularly in the circumferential direction.

[0018] The distal end of said sealing portion of the sealing joint forming with the upper support cover a dynamic annular seal forms a barrier stopping polluting particles heading towards the bearing.

[0019] Preferably, said sealing joint is annular.

[0020] Preferably, said sealing joint is monobloc.

[0021] In a first embodiment, the sealing portion of the sealing joint forms a seal by friction contact with the upper support cover.

[0022] In a second alternative embodiment, the sealing portion of the sealing joint forms a seal by narrow passage(s) with the upper support cover.

[0023] In a third alternative embodiment, the sealing portion of the sealing joint can form both a seal by narrow passage(s) and a seal by friction contact with the upper support cover.

[0024] Advantageously, said sealing portion comprises an intermediate portion extending at least axially towards the upper support cover from the heel of the sealing joint and a distal portion extending at least radially inwards from the intermediate portion of said sealing portion.

[0025] Optionally, the intermediate portion of said sealing portion extends radially outwards and axially towards the upper support cover.

[0026] Optionally, the distal portion of said sealing portion extends radially inwards and axially towards the upper support cover.

[0027] Thus, said sealing portion of the sealing joint is axially flexible.

[0028] According to a particular design, the intermediate portion of said sealing portion extends from a radially inner edge of the heel of the sealing joint, remaining at a distance from a radially outer edge of the heel of the sealing joint.

[0029] Thus, the flexibility of said sealing portion of the sealing joint is improved.

[0030] Advantageously, the hollowed annular radial portion forms a groove, each rib extending from the bottom of said groove.

[0031] Optionally, each rib remains at a distance from a radially inner edge of the hollowed annular radial portion.

[0032] According to a particular design, the lower support cover comprises an annular radial portion and a shoulder extending from said radial portion towards the upper support cover and which is provided with said annular radial portion hollowed out.

[0033] Optionally, the hollowed annular radial portion remains at a distance from a large diameter edge of the shoulder of the lower support cover.

[0034] According to a particular design, the upper support cover includes an outer annular skirt that radially surrounds said sealing gasket. Said outer annular skirt of the upper support cover protects said sealing gasket during handling of the suspension stop device, in particular from shocks during its transport.

[0035] Advantageously, said sealing portion remains at a distance from the annular outer skirt of the upper support cover.

[0036] Alternatively, said sealing portion may be radially in contact with an internal surface of the annular outer skirt of the upper support cover.

[0037] Advantageously, the distal end of said sealing portion is axially in contact with the upper support cover, in particular with a radial portion of the upper support cover.

[0038] Optionally, at least one cavity is formed on the sealing portion and is open towards the upper support cover, said cavity being filled with lubricant. The lubricant-filled cavity in the sealing portion improves the seal between the sealing portion of the seal and the upper support cover by forming a barrier that stops contaminating particles from reaching the bearing. In addition, the lubricant reduces friction between the sealing portion of said seal and the upper support cover, thus reducing wear on the seal and the frictional torque of the thrust bearing. Brief description of the figures

[0039] The present invention will be better understood upon study of the detailed description of embodiments, taken by way of non-limiting examples and illustrated by the accompanying drawings in which:

[0040] [Fig-1] is an axial cross-sectional view of a suspension stop device according to a example of the implementation of the invention;

[0041] [Fig.2] and [Fig.3] are detailed views of the device in [Fig.1]; and

[0042] [Fig.4] is a perspective view of part of a sealing gasket of the device stop of the [Fig.l]. Detailed description of the invention

[0043] The suspension stop device 2 shown in [Fig. 1] is adapted to be installed between a cup or upper support seat in contact with a fixed chassis element of a motor vehicle, and a helical suspension spring. In [Fig. 1], the device 2 is shown in a position assumed to be vertical.

[0044] The device 2, with axis X-X', comprises an upper support cover 4, a lower support cover 6, and a bearing 8 interposed axially between the upper support cover 4 and the lower support cover 6.

[0045] In the illustrated example, the upper support cover 4 and the lower support cover 6 are mounted in direct contact with the bearing 8 without the interposition of an intermediate element. Alternatively, the upper support cover 4 and the lower support cover 6 can be mounted in indirect contact with the bearing 8 with the interposition of an intermediate element.

[0046] As will be described in more detail later, the device 2 further comprises an external annular sealing gasket 10 to prevent the intrusion of pollutants towards bearing 8, the sealing gasket 10 being overmolded onto the lower support cover 6 and extending towards the upper support cover 4.

[0047] The sealing gasket 10 is, for example, made of an elastically deformable material, for example nitrile or elastomer. The sealing gasket 10 can also be made of a more rigid material, for example polyoxymethylene (POM) or steel.

[0048] The upper support cover 4 is here made of a single piece, for example of plastic material, for example such as a polyamide PA 6.6, which may or may not be reinforced with glass fibers.

[0049] The upper support cover 4, with axis X-X', comprises a radial portion 12, an axial annular inner skirt 14, and an axial annular outer skirt 16 radially surrounding the inner skirt 14.

[0050] The radial portion 12 of the upper support cover 4 has an upper surface (not referenced) intended to face the upper support seat, and an opposing lower surface (not referenced) in contact with the bearing 8. Said upper and lower surfaces define the thickness of the radial portion 12 of the upper support cover 4.

[0051] The outer skirt 16 of the upper support cover 4 extends axially from the radial portion 12 of the upper support cover 4. In the illustrated example, the outer skirt 16 of the upper support cover 4 extends a large diameter edge of the radial portion 12 of the upper support cover 4. In particular, the outer skirt 16 radially surrounds the sealing gasket 10.

[0052] The inner skirt 14 of the upper support cover 4 extends inside the bore of the lower support cover 6. The inner and outer skirts 14, 16 of the upper support cover 4 extend axially downwards from the radial portion 12 of the upper support cover 4. The inner skirt 14 extends a small-diameter edge of the radial portion 12 of the upper support cover 4. The outer skirt 16 extends a large-diameter edge of the radial portion 12 of the upper support cover 4.

[0053] The lower support cover 6 is here made of a body made in one piece, for example of plastic material, for example such as a polyamide PA 6.6, which may or may not be reinforced with glass fibers.

[0054] The lower support cover 6, with axis X-X', includes an annular radial portion 18 in the shape of a plate, and an annular axial skirt 20 extending a small diameter edge of the radial portion 18 of the lower support cover 6.

[0055] The axial skirt 20 of the lower support cover 6 extends axially downwards, opposite the upper support cover 4 and the bearing 8. The axial skirt 20 of the lower support cover 6 allows the centering of the suspension spring.

[0056] The radial portion 18 of the lower support cover 6 has a lower annular radial surface (not referenced) delimiting a bearing surface for the suspension spring.

[0057] The upper support cover 4 comprises a plurality of internal hooks 22 arranged on the inner skirt 14 of the upper support cover 4 and extending radially outwards towards the lower support cover 6. In the illustrated example, the hooks 22 are spaced from each other in a circumferential direction. Alternatively, it could be possible to provide a single annular hook 22.

[0058] The lower support cover 6 comprises a plurality of internal hooks 24 arranged on the radial portion 18 of the lower support cover 6 and extending radially inwards towards the upper support cover 4, said plurality of internal hooks 24 being adapted to interfere diametrically with the plurality of internal hooks 22 of the upper support cover 4. Alternatively, it might be possible to provide a single annular hook 24.

[0059] The hooks 22, 24 form retaining means allowing the upper support cover 4 and lower support cover 6 to be axially retained relative to each other.

[0060] The bearing 8 is located radially between the inner and outer skirts 14, 16 of the upper support cover 4. The bearing 8 comprises an upper ring 26 in contact with the upper support cover 4, a lower ring 28 in contact with the lower support cover 6, and a row of rolling elements 30, here balls, arranged between the raceways formed on the rings 26, 28. In the illustrated example, the bearing is of the angular contact type. The upper ring 26 is in contact with the lower surface of the radial portion 12 of the upper support cover 4, said lower surface being complementary in shape to the upper ring 26 of the bearing 8. The lower ring 28 is in contact with an upper surface of the lower support cover 6, said upper surface being complementary in shape to the lower ring 28 of the bearing 8.

[0061] As more clearly illustrated in Figures 2 and 3, the lower support cover 6 comprises an annular radial portion 32 which is hollowed out to allow a plurality of ribs 34 to remain circumferentially spaced. More precisely, the hollowed annular radial portion 32 forms a groove, each rib 34 extending from the bottom of the groove. The ribs 34 are regularly spaced circumferentially. Alternatively, irregularly spaced ribs 34 may be provided.

[0062] The sealing gasket 10 is provided with a heel 36 which is overmolded onto the hollowed part of the hollowed annular radial portion 32 and onto the ribs 34, and a sealing portion 38 which is supported by the heel 36 and which extends towards the hood upper support 4. The sealing gasket 10 is annular and is mounted radially around the bearing 8.

[0063] The distal end of the sealing portion 38 of the sealing joint 10 forms with the upper support cover 4 a dynamic annular seal, the distal end of the sealing portion 38 being here axially in contact with the upper support cover 4, and more precisely with a lower surface of the radial portion 12 of the upper support cover 4. The distal end of the sealing portion 38 is here radially offset outwards relative to the bearing 8.

[0064] In addition, the lower support cover 6 includes a shoulder 40 which is in the axial extension of the outer skirt 16 of the upper support cover 4 and in which the hollowed annular radial portion 32 is formed. In other words, the outer skirt 16 of the upper support cover 4 is located axially above the shoulder 40.

[0065] The shoulder 40 of the lower support cover 6 is formed by a first concave surface 42 of the lower support cover 6 and a second surface 44 of the lower support cover 6 extending purely radially. The first surface 42 of the lower support cover 6 extends from a large-diameter edge of the second surface 44 of the lower support cover 6.

[0066] Alternatively, the first surface 42 of the shoulder 40 could be flat and extend purely axially, or both axially and radially, i.e., obliquely. Alternatively, the second surface 44 of the shoulder 40 could extend both radially outwards and axially downwards.

[0067] The hollowed annular radial portion 32 remains here at a distance from a large diameter edge of the shoulder 40 of the lower support cover 6 and in particular from the first surface 42 of the shoulder 40.

[0068] Each rib 34 extends from the bottom of the hollowed annular radial portion 32, remaining radially at a distance from a radially inner edge of the hollowed annular radial portion 32 and remaining axially at a distance from the second surface 44 of the shoulder 40.

[0069] The sealing portion 38 of the sealing joint 10 extends into an annular space 46 which exists radially between the outer skirt 16 of the upper support cover 4 and the bearing 8 and axially between the radial portion 12 of the upper support cover 4 and the second surface 44 of the shoulder 40. The sealing portion 38 of the sealing joint 10 remains here at a distance from the annular outer skirt 16 of the upper support cover 4, which improves the flexibility of the sealing portion 38 of the sealing joint 10.

[0070] The section of the sealing gasket 10 is S-shaped. In particular, the sealing portion 38 of the sealing gasket 10 comprises an intermediate portion 48 extending radially outwards and axially towards the upper support cover. 4 from the heel 36 of the sealing joint 10 and a distal portion 50 extending radially inwards and axially towards the upper support cover 4 from the intermediate portion 48 of the sealing portion 38.

[0071] More specifically, the intermediate portion 48 of the sealing portion 38 extends from a radially inner edge of the heel 36 of the sealing joint 10, remaining at a distance from a radially outer edge of the heel 36 of the sealing joint 10.

[0072] As illustrated in [Fig.4], a plurality of notches 52 are formed in the heel 36 of the sealing gasket 10 by each of the ribs.

[0073] In the illustrated embodiments, the device 2 includes a single external sealing gasket 10 located radially between the lower support cover 6 and the external skirt 16 of the upper support cover 4. In combination, the device 2 may include an internal sealing gasket located radially between the lower support cover 6 and the internal skirt 14 of the upper support cover 4.

[0074] In the illustrated embodiments, the device 2 comprises a single external sealing gasket 10 with a single sealing portion. Alternatively, the device 2 may comprise a plurality of external sealing gaskets or a single sealing gasket with a plurality of sealing portions.

[0075] In the illustrated embodiments, device 2 includes a bearing 8. An angular contact bearing with a single row of balls. Device 2 may include other types of bearings, for example, a four-point contact bearing and / or one with at least two rows of balls. The bearing may include other types of rolling elements 30, for example, rollers. In another embodiment, the bearing of device 2 may include a sliding bearing without rolling elements and equipped with one or more rings.

Claims

Demands

1. Suspension stop device (2) comprising a lower support cover (6), an upper support cover (4), and at least one bearing (8) disposed between said covers, characterized in that: - the lower support cover (6) comprises an annular radial portion (32) which is at least partially hollowed out so as to leave a plurality of ribs (34) spaced from each other in the circumferential direction; - the suspension stop device (2) further comprises a sealing joint (10) which is provided with a heel (36) overmolded on the hollowed part of said hollowed annular radial portion (32) and on the ribs (34), and which is provided with a sealing portion (38) supported by the heel (36) and extending towards the upper support cover (4); and - the distal end of said sealing portion (38) of the sealing joint (10) forms with the upper support cover (4) a dynamic annular seal.

2. Suspension stop device (2) according to claim 1, wherein said sealing joint (10) comprises an intermediate portion (48) extending at least axially towards the upper support cover (4) from the heel (36) of the sealing joint (10) and a distal portion (50) extending at least radially inwards from the intermediate portion (48) of said sealing portion (38).

3. Suspension stop device (2) according to claim 2, wherein the intermediate portion (48) of said sealing portion (38) extends radially outwards and axially towards the upper support cover (4), the distal portion (50) of said sealing portion (38) extends radially inwards and axially towards the upper support cover (4).

4. Suspension stop device (2) according to claim 2 or 3, wherein the intermediate portion (48) of said sealing portion (38) extends from a radially inner edge of the heel (36) of the sealing joint (10), remaining at a distance from a radially outer edge of the heel (36) of the sealing joint (10).

5. Suspension stop device (2) according to any one of claims 1 to 4, wherein the hollowed annular radial portion (32) forms a groove, each rib (34) extending from the bottom of said groove.

6. Suspension stop device (2) according to any one of claims 1 to 5, wherein each rib (34) remains at a distance from a radially inner edge of the hollowed annular radial portion (32).

7. Suspension stop device (2) according to any one of claims 1 to 6, wherein the lower support cover (6) comprises an annular radial portion (18) and a shoulder (40) extending from said radial portion (18) towards the upper support cover (4) and which is provided with said hollowed annular radial portion (32).

8. Suspension stop device (2) according to claim 7, wherein the hollowed annular radial portion (32) remains at a distance from a large diameter edge of the shoulder (40) of the lower support cover (6).

9. Suspension stop device (2) according to any one of claims 1 to 8, wherein said sealing portion (38) remains at a distance from an annular external skirt (16) of the upper support cover (4).

10. Suspension stop device (2) according to any one of claims 1 to 9, wherein the distal end of said sealing portion (38) is axially in contact with the upper support cover (4).

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