FR3119114A1 - Sealed suspension stopper device - Google Patents

Abstract

The device comprises a lower support cover 16, an upper support cover 14, and at least one bearing 18 disposed between said covers and comprising at least one upper ring 20 in contact with the upper support cover 14 and a lower ring 22 in contact with the lower support cover 16. The device further comprises at least one seal 19 fixed relative to one of the upper support and lower support covers and to the upper 20 or lower 22 ring of the bearing associated with said cover. Said seal 19 is in frictional contact against the other ring of the bearing and closes an annular space 34 remaining between two free ends of said other ring and of said ring associated with said cover. Figure for abstract: Fig 2

Description

Sealed suspension stopper device

Technical field of the invention

The present invention relates to the field of suspension thrust bearing devices used in particular for motor vehicles in the suspension struts of the steered wheels.

State of the prior art

A suspension thrust bearing device generally comprises a bearing forming an axial thrust bearing and upper and lower covers forming a housing for the rings of the bearing and making it possible to provide the interface between said rings and the neighboring elements.

The suspension thrust bearing device is arranged in the upper part of the suspension strut between a suspension spring and the vehicle body. The suspension spring is mounted around a shock absorber piston rod, the end of which is linked to the vehicle body. The suspension spring, of the helical spring type, bears axially directly or indirectly on the lower cover of the suspension thrust bearing device.

The suspension thrust bearing device makes it possible to transmit axial and radial forces between the suspension spring and the body of the vehicle while allowing a relative rotational movement between the lower cover and the upper cover resulting from a turning of the steering wheels of the vehicle and/or compression of the suspension spring.

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

The hooks form retaining means making it possible to axially retain the upper and lower cowls relative to each other. These hooks also form narrow passages in order to limit the intrusion of polluting particles radially between the outer or inner skirt of the upper cowl and the lower cowl.

However, a bump stop device is generally exposed to various types of pollution.

With such a device, polluting particles and water can easily infiltrate between the external or internal skirt of the upper cover and the lower cover, then be directed towards the bearing and be introduced inside the latter.

The present invention aims to remedy this drawback.

The invention relates to a suspension thrust bearing device comprising a lower support cover, an upper support cover, and at least one bearing arranged between said covers and comprising at least one upper ring in contact with the upper support cover and a lower ring in contact with the lower support cover.

According to a first general characteristic, the device further comprises at least one fixed seal relative to one of the lower support and upper support covers and to the upper or lower ring of the bearing associated with said cover.

According to a second general characteristic, said seal is in frictional contact against the other ring of the bearing.

According to a third general characteristic, said seal closes an annular space remaining between a free end of said other ring and a free end of said ring associated with said cover.

The seal makes it possible to limit the intrusion of dust, water and other types of polluting particles inside the bearing in a particularly effective manner insofar as it seals off said annular space through which these particles are likely to penetrate.

Preferably, said two free ends of said other ring and of said ring associated with said cover are located in the same radial plane of the device.

In one embodiment, said seal is in frictional contact against said free end of said other ring of the bearing. Alternatively, said seal may come into frictional contact against another zone of said other ring of the bearing.

According to one mode of assembly, said seal bears against said ring of the bearing associated with said cover. The lower or upper surface of said cowl may comprise a bearing portion in contact with the bearing, and a mounting portion offset with respect to the bearing portion axially on the side of said other cowl and against which said seal is mounted .

Said seal may comprise a heel for the fixed mounting relative to said cover and to said ring associated with said cover, and a sealing portion extending said heel and being in frictional contact against said other ring of the bearing.

Said seal may be located radially at least partly between the bearing and a skirt of the upper bearing cover. The skirt may be an outer skirt of the upper support cover which radially surrounds at least partly the support cover, or an inner skirt which extends at least partly into the bore of said support cover.

According to a particular design, the device comprises a first seal fixed relative to the upper support cover and to the upper ring of the bearing associated with said cover and in frictional contact against the lower ring of the bearing, and a second seal fixed relative to the lower support cover and to the lower ring of the bearing associated with said cover and in frictional contact against the upper ring of the bearing. The first and second seals block upper and lower annular spaces which respectively remain between two upper free ends and two lower free ends of said rings.

The bearing may further comprise at least one row of rolling elements arranged between the upper and lower rings, and at least one cage for the circumferential spacing of the rolling elements of said row.

When the device is fitted with first and second seals, these advantageously delimit between the upper and lower rings a sealed space inside which said row of rolling elements and said cage are housed.

Brief description of figures

The present invention will be better understood on studying the detailed description of embodiments, taken by way of non-limiting examples and illustrated by the appended drawings in which:

is a sectional view of a suspension thrust bearing device according to a first embodiment of the invention,

is a detail view of the ,

is a sectional view of a suspension thrust bearing device according to a second embodiment of the invention, and

is a detail view of the .

Detailed description of the invention

The suspension thrust bearing device 10 represented on the is adapted to be installed between a cup or upper support seat coming into contact against an element of the fixed frame of a motor vehicle, and a suspension spring of the helical type. On the , the device 10 is shown in an assumed vertical position.

The device 10, with axis 12, comprises an upper support cover 14, a lower support cover 16, and a rolling bearing 18 interposed axially between said covers. In the example illustrated, the covers 14, 16 are mounted in direct contact with the bearing 18 without the interposition of an intermediate element. Alternatively, the covers 14, 16 can be mounted in indirect contact with the bearing 18 with the interposition of an intermediate element.

As will be described in more detail below, the device 10 further comprises an external seal 19 to prevent the intrusion of pollutants towards the bearing 18. In the example illustrated, the seal 19 is maintained axially between the upper support cover 14 and the bearing 18.

The upper support cover 14 may be 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.

The support cover 14, with axis 12, comprises a radial portion 14a, an annular axial inner skirt 14b, and an annular axial outer skirt 14c radially surrounding the inner skirt. The radial portion 14a has an upper surface 15 intended to come opposite the upper bearing seat, and an opposite lower surface 17 in contact with the bearing 18. The upper and lower surfaces 15, 17 define the thickness of the radial portion 14a. In the example illustrated, the upper surface 15 of the support cover is oriented perpendicular to the axis 12 of the device. As a variant, the upper surface 15 of the support cover could be oriented perpendicularly with respect to an axis forming a non-zero angle with the axis 12 of the device.

The outer skirt 14c of the support cover radially partially surrounds the lower support cover 16. The outer skirt 14c extends axially. The outer skirt 14c extends axially from the radial portion 14a. In the example shown, the outer skirt 14c extends a large diameter edge of the radial portion 14a.

The inner skirt 14b of the support cover extends inside the bore of the lower support cover 16. The inner and outer skirts 14b, 14c extend axially downward from the radial portion 14a. The inner skirt 14b extends a small diameter edge of the radial portion 14a.

The bearing 18 is located entirely radially between the skirts 14b, 14c of the upper support cover 14. The bearing 18 comprises an upper ring 20 in contact with the upper support cover 14, a lower ring 22 in contact with the lower support cover 16, and a row of rolling elements 24, here balls, arranged between the tracks bearings formed on the rings. The bearing 18 also includes a cage 26 for the circumferential spacing of the rolling elements 24. The cage 26 is here arranged radially between the upper 20 and lower 22 rings.

In the example shown, bearing 18 is of the angular contact type. The upper ring 20 is in contact with the lower surface 17 of the upper support cover. The lower ring 22 is in contact with an upper surface of the lower support cover 16.

The lower support cover 16 may consist 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.

The support cover 16, with axis 12, comprises an annular radial portion 28a in the form of a plate, and an annular axial skirt 28b which extends a small-diameter edge of the radial portion 28a. The skirt 28b extends axially opposite the upper support cover 14 and the bearing 18. The skirt 28b allows the centering of the suspension spring. The radial portion 28a has a lower annular radial surface 30 delimiting a support surface for the suspension spring, and an upper surface 32 in contact with the lower ring 22 of the bearing and of complementary shape. The upper and lower surfaces 32, 30 define the thickness of the radial portion 28a.

As indicated above, the outer seal 19 is held axially between the upper support cover 14 and the bearing 18. The seal 19 is fixed relative to the support cover 14. The seal 19 is also fixed relative to the upper ring 20 of the bearing which is associated with the support cover 14. The seal 19 is located radially in part between the outer skirt 14c of the support cover and the upper ring 20 of the bearing. The seal 19 is annular.

As is illustrated more visibly in , the seal 19 is held axially between the lower surface 17 of the upper support cover and the upper ring 20 of the bearing.

The seal 19 is in frictional contact with the lower ring 22 of the bearing. The seal 19 is in frictional contact with the upper free end of the lower ring 22 of the bearing. The seal 19 closes off the annular space 34 remaining between the upper free end of the lower ring 22 and the upper free end of the upper ring 20. The upper free ends of the lower 22 and upper 20 rings are located in the same radial plane perpendicular to the axis of the device. Space 34 is here radial.

The lower surface 17 comprises a bearing portion 17a in contact with the upper ring 20 of the bearing, and a mounting portion 17b offset axially upwards with respect to the bearing portion 17a. The assembly portion 17b radially surrounds the support portion 17a. The seal 19 is mounted axially bearing against the mounting portion 17b of the upper surface of the support cover.

The seal 19 is provided with an annular heel 19a which is held axially between the lower surface 17 of the upper support cover and the upper ring 20 of the bearing. The heel 19a is held axially between the mounting portion 17b of the lower surface 17 of the support cover and the upper ring 20 of the bearing. In the illustrated embodiment, the heel 19a delimits the bore of the seal 19.

The seal 19 is also provided with an annular sealing portion 19b which extends in the direction of the lower ring 22 of the bearing and in frictional contact with the upper free end of this lower ring. The heel 19a and the sealing portion 19b block the space 34 existing between the upper free ends of the lower ring 22 and the upper ring 20 of the bearing.

The sealing portion 19b of the gasket extends from the heel 19a. The sealing portion 19b extends outward from the heel 19a. The sealing portion 19b extends obliquely downwards.

The sealing portion 19b of the seal forms a dynamic seal with the lower ring 22 of the bearing over 360°. By “dynamic sealing”, we mean a sealing between two parts likely to have relative movement. The heel 19a of the seal is in static sealing contact with the support cover 14 and the upper ring 20 of the bearing over 360°.

The seal 19 can for example be made of a rigid material, for example polyoxymethylene (POM). Alternatively, the seal 19 can also be made of a less rigid material, for example nitrile or elastomer. The seal 19 is advantageously made in one piece, for example by molding.

The embodiment illustrated in , on which the identical elements bear the same references, differs from the previous embodiment in that the device also comprises an internal seal 38 held axially between the support cover 16 and the bearing 18.

The internal seal 38 is fixed relative to the support cover 16. The internal seal 38 is also fixed relative to the lower ring 22 of the associated bearing. The internal seal 38 is located radially in part between the internal skirt 14b of the support cover and the lower ring 22 of the bearing. The internal seal 38 is annular.

As is illustrated more visibly in , the internal seal 38 is held axially between the upper surface 32 of the lower support cover and the lower ring 22 of the bearing.

The internal seal 38 is in frictional contact with the upper ring 20 of the bearing. The internal seal 38 is in frictional contact with the lower free end of the upper race 20 of the bearing. The internal seal 38 closes off the annular space 40 remaining between the lower free end of the upper ring 20 and the lower free end of the lower ring 22. The lower free ends of the lower 22 and upper 20 rings are located in the same radial plane. Space 40 is here radial.

The internal seal 38 and the external seal 19 define between the upper 20 and lower 22 rings of the bearing a sealed space inside which the rolling elements 24 and the cage 26 are housed.

The upper surface 32 of the support cover comprises a bearing portion 32a in contact with the lower race 22 of the bearing, and a mounting portion 32b offset axially downwards with respect to the bearing portion 32a. The support portion 32a radially surrounds the mounting portion 32b. The internal seal 38 is mounted axially bearing against the mounting portion 32b of the upper surface of the support cover.

The internal seal 38 is provided with an annular heel 38a which is held axially between the upper surface 32 of the lower support cover and the lower ring 22 of the bearing. The heel 19a is held axially between the mounting portion 32b of the upper surface 32 of the support cover and the lower race 22 of the bearing.

The internal seal 38 is also provided with an annular sealing portion 38b which extends in the direction of the upper ring 20 of the bearing and in frictional contact with the lower free end of this lower ring. The heel 38a and the sealing portion 38b close off the space 40 existing between the lower free ends of the lower ring 22 and the upper ring 20 of the bearing.

The sealing portion 38b of the internal seal extends from the heel 38a. Sealing portion 38b extends inward from heel 19a. The sealing portion 38b is shaped so as not to interfere with the cage 26 of the bearing.

The sealing portion 38b of the internal seal forms a dynamic seal with the upper ring 20 of the bearing over 360°. The heel 38a of the internal seal is in static sealing contact with the support cover 16 and the lower ring 22 of the bearing over 360°.

In the illustrated embodiment, the sealing portion 38b of the internal seal is provided with a first frustoconical part extending inwards obliquely downwards the heel 38a, with a radial part extending this frustoconical part , a second frustoconical part extending obliquely upwards and inwards the radial part and coming into contact against the upper ring 20 of the bearing, and an axial rim which extends the second frustoconical part upwards. Alternatively, the sealing portion 38b of the internal seal 38 could have another shape.

In the embodiments illustrated, the seal 19, 38 comes into frictional contact only with the lower ring 22, upper ring 20 of the bearing. Alternatively, the seal 19, 38 could also comprise an additional sealing lip extending in the direction of one of the bearing 14 and support 16 covers to form a labyrinth type and/or friction seal. .

In the embodiments illustrated, the outer seal 19 is mounted axially between the upper race 20 of the bearing and the support cover 14. Alternatively, the outer seal could be mounted axially between the lower race 22 of the bearing and the support cover 16, and rub against the upper ring 20 of the bearing. In another embodiment, the external seal 19 could be fixed on the support cover 14 and come to rub against the lower ring 22 of the bearing, or be fixed on the support cover 16 and come to rub against the ring upper 20 of the landing. In another embodiment, the outer seal 19 could be fixed on the upper ring 20 of the bearing and rub against the lower ring 22 of the bearing, or vice versa.

In the second illustrated embodiment, the internal seal 38 is mounted axially between the lower race 22 of the bearing and the support cover 16. Alternatively, the internal seal could be mounted axially between the upper race 20 of the bearing and the support cover 14 and come to rub against the lower ring 22 of the bearing. In another embodiment, the external seal 19 could be fixed on the support cover 16 and come to rub against the upper race 20 of the bearing, or be fixed on the support cover 14 and come to rub against the ring lower 22 of the bearing. In another embodiment, the outer seal 19 could be fixed on the lower ring 22 of the bearing and rub against the upper ring 20, or vice versa.

In the embodiments illustrated, the device comprises either the external seal 19 or the external seal 19 and the internal seal 38. Alternatively, the device could include only the internal seal 38.

In the embodiments illustrated, the device comprises an angular contact rolling bearing provided with a row of balls. The device may include other types of rolling bearings, for example a bearing with four contact points and/or with at least two rows of balls. The rolling bearing can include other types of rolling elements, for example rollers. In another variant, the device may comprise a sliding bearing devoid of rolling elements and provided with one or more rings.

Claims (10)

Suspension thrust bearing device comprising a lower support cover (16), an upper support cover (14) and at least one bearing (18) disposed between said covers and comprising at least one upper ring (20) in contact with the upper support cover (14) and a lower ring (22) in contact with the lower support cover (16), characterized in that it further comprises at least one seal (19; 38) fixed relatively to one of the upper bearing and lower support covers and to the upper (20) or lower (22) ring of the bearing associated with said cover, said seal (19; 38) being in frictional contact against the another ring of the bearing and closing off an annular space (34; 40) remaining between two free ends of said other ring and of said ring associated with said cover. Device according to Claim 1, in which the said two free ends of the said other ring and of the said ring associated with the said cover are situated in the same radial plane of the device. Device according to Claim 1 or 2, in which the said seal (19; 38) is in frictional contact against the said free end of the said other ring of the bearing. Device according to any one of the preceding claims, in which the said seal (19; 38) bears against the said bearing ring associated with the said cover. Device according to Claim 4, in which the said seal (19; 38) is maintained axially between the said cover and the said associated ring. Device according to any one of the preceding claims, in which said seal (19; 38) comprises a heel (19a; 38a) for fixed mounting relative to said cover and to said ring associated with said cover, and a portion of seal (19b; 38b) extending said heel and being in frictional contact against said other ring of the bearing. Device according to any one of the preceding claims, in which the said seal (19; 38) is located radially at least partly between the bearing (18) and a skirt of the upper support cover. Device according to any one of the preceding claims, comprising a first seal (19) fixed relative to the upper support cover (14) and to the upper ring (20) of the bearing associated with the said cover and in frictional contact against the lower ring (22) of the bearing, and a second seal (38) fixed relative to the lower support cover (16) and to the lower ring (22) of the bearing associated with said cover and in frictional contact against the upper ring ( 20) of the bearing, the first and second seals 19; 38) closing off upper and lower annular spaces (34; 40) remaining respectively between two upper free ends and two lower free ends of said rings. Device according to any one of the preceding claims, in which the bearing (18) further comprises at least one row of rolling elements (24) arranged between the upper (20) and lower (22) races, and at least one cage (26) for the circumferential spacing of the rolling elements of said row. Device according to Claim 9 dependent on Claim 8, in which the first and second seals 19; 38) delimit between the upper rings (20) and lower (22) a sealed space inside which are housed said row of rolling elements (24) and said cage.