FR3029993A1 - BEARING BEARING COMPRISING AN ELASTIC SEALING FLANGE - Google Patents

Abstract

The rolling bearing comprises an outer ring 14, an inner ring 16, at least one row of rolling elements 18 arranged radially between the rings, at least one seal 22 fixed on one of the rings 14 and cooperating with the another ring 16, and at least one flange 26 sealing attached to said other ring 16. The flange 26 is at least partly elastically deformable in the axial direction. The flange 26 comprises at least one bearing portion 26b mounted axially in contact with an outer side face 36 of said seal. The flange 26 is deformed axially by the axial contact between said seal 22 and said bearing portion 26b.

Description

The present invention relates to the field of rolling bearings, and in particular those used in automotive or industrial applications. In a rolling bearing, one or more seals are generally used to maintain the lubricant, such as grease, within the bearing and to limit the entry of polluting particles. Generally, such seals are attached to one of the bushings of the bearing and cooperate with the other bushing to form a dynamic seal. The patent application WO-A1-2010 / 133240 (SKF) describes a rolling bearing comprising two seals fixed on the outer ring and each comprising an inner lip in frictional contact with the inner ring. The bearing further comprises two sealing flanges fixed on the inner ring and each of which rubs an outer lip of the associated seal. The use of such a flange axially on each side of the bearing and cooperating with the outer lip of the associated seal makes it possible to limit the arrival of polluting particles to the inner lip of said seal in frictional contact with the ring. interior. However, the contact pressure exerted on the flange by the outer elastomer lip of each associated seal tends to decrease over time and in the event of angular misalignment of one of the rings relative to the other after mounting of the bearing. This may affect the sealing properties of the bearing in operation. The present invention aims to remedy this disadvantage. More particularly, the present invention aims to provide a rolling bearing having improved sealing.

The present invention also aims to provide a rolling bearing simple to manufacture and assemble. In one embodiment, the rolling bearing comprises an outer ring, an inner ring, at least one row of rolling elements arranged radially between the rings, at least one seal attached to one of the rings and cooperating with the other ring to form a seal, and at least one sealing flange fixed on said other ring. Said sealing flange is at least partly elastically deformable in the axial direction and comprises at least one bearing portion mounted axially in contact with an outer lateral face of said seal. Said sealing flange is deformed axially by the axial contact between said seal and said bearing portion.

The axial deformation of the sealing flange combined with its resilient nature makes it possible to maintain the axial contact between the bearing portion of said flange and the seal. In reaction to the deformation of the flange against its elasticity, the bearing portion exerts a permanent axial prestressing force on the seal. In this way, good sealing properties are maintained over time. Preferably, said sealing flange comprises a fastening portion for fastening the flange to said other ring and a connecting portion connecting said fastening portion and said bearing portion, at least said connecting portion being elastically deformable in said flange. the axial direction. Said connecting portion may extend inward towards the seal. In one embodiment, said connecting portion has a curved shape.

In one embodiment, said seal comprises at least one seal defining the outer side face. Preferably, said seal is made of a flexible material and said bearing portion of the sealing flange is made of a rigid material.

Said bearing portion of the sealing flange may be made of a metallic material. This facilitates the dissipation of heat that is generated by the sliding axial contact between the flange and the associated seal. The connecting portion may be made of a flexible material, in particular in a synthetic or polymeric material. Alternatively, the connecting portion may be made of metal material for example spring steel. The bearing, connecting and fixing portions may be made of the same material or different materials.

Preferably, the outer side face of said seal is axially offset from the inner side of the bearing relative to a front surface of said ring. In one embodiment, the seal comprises a reinforcing insert at least partially covered by said seal gasket. Said support portion of the sealing flange may form an end portion of said flange. Said bearing portion of the sealing flange may have a convex shape axially on the side of said seal. Thus, the frictional torque between the seal and the associated flange is reduced. In addition, any contact between a sharp end edge of the bearing portion of the flange with the seal is prevented so as to prevent any deterioration of said seal. Preferably, the seal is axially offset from the inner side of the bearing relative to a front surface of said ring. In one embodiment, said sealing flange may be mounted axially bearing directly against a front surface of said ring.

In one embodiment, said sealing flange comprises at least one undulation distinct from said bearing portion and extending axially. The bearing portion may extend axially on the outer side of the bearing or alternatively axially on the inner side of the bearing.

In a particular embodiment, the external lateral face of said seal comprises at least two annular ribs against which said bearing portion of the sealing flange comes into axial contact, at least one closed annular space being delimited. by said flange and said ribs and within which is disposed at least one lubricant. The present invention will be better understood on studying the detailed description of embodiments taken by way of nonlimiting examples and illustrated by the appended drawings, in which: FIG. 1 is a half-view in axial section of FIG. A rolling bearing according to a first exemplary embodiment of the invention, - Figure 2 is a detail view of Figure 1 partially illustrating a sealing flange of the bearing, - Figure 3 is a partial sectional view. of the sealing flange of FIG. 2 in the free state, FIG. 4 is a detailed view of a rolling bearing according to a second exemplary embodiment of the invention, and FIG. axial sectional view of a rolling bearing according to a third embodiment of the invention. In FIG. 1, a rolling bearing 10 having an axis 12 comprises an outer ring 14, an inner ring 16, a plurality of rolling elements 18, here made in the form of balls, arranged radially between said rings and a cage 20 of maintaining the regular circumferential spacing of the rolling elements. The bearing 10 comprises, axially on each side, an annular sealing gasket 22, 24 for closing the radial space existing between the outer and inner rings 14 and an annular sealing flange 26, 28 bearing axially against said seal 22, 24 on the outer side of the bearing. In the exemplary embodiment illustrated, the seals 22, 24 of sealing are fixed on the outer ring 14 while the flanges 26, 28 of sealing are fixed on the inner ring 16. The outer ring 14 comprises an outer surface 14a cylindrical axial axis, a cylindrical bore 14b, two opposite radial face surfaces 14c, 14d axially delimiting said bore and the outer surface, and a raceway formed on the bore 14b and having in cross section a concave internal profile adapted to the rolling elements 18, said raceway being directed radially inwardly. The outer ring 14 also includes two annular grooves 14e, 14f formed on the bore 14b and extending radially outwardly. The grooves 14e, 14f are respectively disposed in the vicinity of the end surfaces 14c, 14d. Each groove 14e, 14f is disposed axially between the rolling elements 18 and one of the end surfaces 14c, 14d. The grooves 14e, 14f are symmetrical with each other with respect to a radial median plane passing through the center of the bearing 10. The inner ring 16 comprises a cylindrical bore 16a, an outer axial surface 16b cylindrical, two opposite radial frontal surfaces 16c, 16d defining axially said bore and the outer surface, and a raceway formed on the outer surface 16b and having in cross section a concave internal profile adapted to the rolling elements 18, said raceway being directed radially outwardly. The cage 20 is disposed radially in the radial space delimited by the outer surface 16b of the inner ring and the bore 14b of the outer ring. The inner ring 16 also includes two annular grooves 16e, 16f formed on the outer surface 16b and extending radially inwardly. The grooves 16e, 16f are disposed respectively in the vicinity of the end surfaces 16c, 16d. The grooves 16e, 16f are symmetrical with each other with respect to the radial median plane of the bearing 10. The groove 16e, 16f is radially opposite the corresponding groove 14e, 14f. The outer ring 14 and inner ring 16 are concentric.

In the exemplary embodiment illustrated, the rings are massive. The term "solid ring" means a ring whose shape is obtained by machining with chip removal (turning, grinding) from tubes, bars, forged blanks and / or rolled. Each sealing gasket 22, 24 is disposed radially between the outer and inner rings 14 and fixed to said outer ring by being disposed laterally to the rolling elements 18. Each gasket 22, 24 is secured within a housing. grooves 14e, 14f of the outer ring. Each sealing gasket 22, 24 is entirely housed inside the radial space delimited by the outer and inner rings 14. Each gasket 22, 24 is axially offset on the inside of the bearing 10 relative to the outer ring. side surface 14c, 14d associated with the outer ring. In this exemplary embodiment, the seals 22, 24 of sealing 5 are identical to each other and symmetrical with respect to the radial median plane of the bearing 10. The seals 22, 24 being here identical, only one of them will be described. . The seal 22 comprises a rigid annular armature or insert 30 and a flexible annular seal 32 attached to the insert. The insert 30 is made of a rigid material, for example metal material or thermoplastic material including polyamide. The insert 30 forms a reinforcing insert of the gasket 32. The gasket 32 is overmoulded or vulcanized on the insert 30. The gasket 32 is made of a flexible material, for example an elastomer such as a nitrile rubber or thermoplastic elastomer. The gasket 32 covers an outer surface of the insert 30. The gasket 32 covers an outer lateral face of the insert 30. The gasket 32 comprises an annular outer lateral face 36 oriented axially on the outer side of the bearing 10 in the direction of the flange 26 associate. The outer side face 36 is axially offset from the inner side of the bearing 10 relative to the end surfaces 14c, 16c of the outer and inner rings. The side face 36 of the liner forms the outer lateral face of the seal 22. The side face 36 is flat. The lateral face 36 extends radially. An internal lateral face 38 of the seal opposite to said lateral face 36 is oriented axially towards the inside of the bearing in the direction of the rolling elements 18. The internal lateral face 38 is delimited by the insert 30. The lining 32 forms two portions of sealing radially opposed 30 respectively exerting a static seal with the outer ring 14 and a dynamic seal with the inner ring 16. The term "static seal", the seal formed between two parts without relative movement and by "sealing 3029993 7 dynamic" , a seal between two parts having a relative movement. The outer sealing portion of the gasket 32 is force-fitted into the groove 14e of the outer ring 14 to secure the gasket 22 to said ring. In the zone of the groove 14e, the outer sealing portion is in complementary form with said groove to form a means for fixing the seal 22 on the outer ring 14. The outer sealing portion surrounds radially and axially the large diameter free edge of the insert 30 so that only the liner 32 is in contact with the outer ring 14. This promotes good retention in position of the seal 22 inside the groove 14e by force fitting and friction. The inner sealing portion of the liner 32 includes first and second concentric annular inner lips 32a, 32b extending axially inwardly of the bearing. The inner lip 32b bears axially against a radial wall of the groove 16e of the inner ring. The inner lip 32a has a larger diameter than the inner lip 32b and radially surrounds the outer surface 16b of the inner ring to form a labyrinth-like narrow passageway with said outer surface. Each flange 26, 28 sealing is axially offset relative to the seal 22, 24 associated with the outer side of the bearing. Each flange 26, 28 of sealing is mounted axially in abutment 25 against one of the end surfaces 16c, 16d of the inner ring and abuts against the gasket seal 32 of the axially associated joint on the outer side of the bearing 10. The flanges 26, 28 are symmetrical with each other with respect to the transverse radial plane passing through the center of the bearing 10. The flanges 26, 28 being identical in the embodiment illustrated, here will be described only one of them. The flange 26 is made in one piece. The flange 26 is made of a rigid material, for example metal material advantageously from a side sheet by cutting and 3029993 8 stamping. Alternatively, the flange 26 could be made of another rigid material, for example synthetic material such as polyamide. The flange 26 is fixed on the inner ring 16 and extends radially towards the outer ring 14. The flange 26 is fixed on the inner ring 16 by any appropriate means, for example by gluing or welding. The flange 26 is mounted axially in contact against the front surface 16c of the inner ring. The flange 26 is fixed on this front surface 16c. In the exemplary embodiment illustrated, the flange 26 is mounted in direct contact against said inner ring. Alternatively, it may be possible to interpose axially an intermediate element between the inner ring 16 and the flange 26. The flange 26 is axially supported against the outer side face 36 of the seal. In the exemplary embodiment illustrated, the flange 26 is mounted axially in abutment against the lateral face 36 in the vicinity of the outer sealing portion of the seal 32. The flange 26 comprises an axially oriented inner lateral face 40 of the 22 of the sealing gasket and coming 20 locally in abutment against said seal, and an external lateral face 42 oriented axially on the outer side of the bearing. The flange 26 is mounted in direct contact against the seal 22. The flange 26 comprises an annular fixing portion 26a mounted axially bearing against the front surface 16c of the inner ring 25 and a bearing portion 26b on the ring-shaped seal 22 and in axial contact with the lateral face 36. external of said seal. The fixing portion 26a has a radial shape and forms an inner portion of the flange. The bearing portion 26b forms an outer portion or end of said flange. In the exemplary illustrated embodiment, the bearing portion 26b has a bent shape concave axially axially on the outer side and convex axially on the inner side. The bearing portion 26b is mounted axially in contact against the seal 32 of the seal. Only 3029993 9 the bearing portion 26b of the flange is mounted in contact against the seal 22. The flange 26 also comprises an annular connecting portion 26c extending between the fixing portions 26a and support 26b 5 being connected to said portions. The connecting portion 26c radially extends the fixing portion 26a and is extended radially by the bearing portion 26b. The connecting portion 26c is shaped to be flexible and elastically deformable in the axial direction. The connecting portion 26c extends inwardly towards the seal 22. In the illustrated embodiment, the connecting portion 26c has a curved shape axially inwardly of the bearing 10. A corrugation 44 is formed on the connecting portion 26c so as to further promote the elastically flexible and deformable character in the axial direction of this portion. The corrugation 44 extends axially on the outside of the bearing 10. In the exemplary embodiment illustrated, the corrugation 44 extends from the edge of large diameter of the fastening portion 26a of the flange. The flange 26 here comprises a single corrugation 44. Alternatively, the flange 26 may comprise a plurality of successive corrugations in the radial direction or other forms promoting the elastic deformation of the connecting portion 26c. The flange 26 is deformed axially towards the outside of the bearing by the contact between the bearing portion 26b and the seal 22.

The connecting portion 26c of the flange is deformed against its own elasticity. The flange 26 is prestressed axially by the contact with the seal 22. In the prestressed state, the axial offset Eprestress (FIG. 2) between the fixing portion 26a and the bearing portion 26b on the side of the inner face 40 of the flange is smaller than the axial distance Ehbre between said portions. the free state of said flange or unsolicited illustrated in Figure 3. By elasticity, the connecting portion 26c of the flange tends to resume its unconstrained position or not solicited axially. The bearing portion 26b of the flange thus exerts an axial force of 3029993 10 permanent prestressing on the seal 22. Good sealing properties are maintained over time by maintaining the sliding axial contact between the bearing portion 26b of the flange and the seal 22. Indeed, it limits the intrusion of polluting particles between the bearing portion 26b of the flange and the seal 22. It limits the arrival of these particles to the dynamic sealing portion of the seal 22 which cooperates with the inner ring 16 maintaining upstream of this portion axial contact between said seal and the flange 26.

In the exemplary embodiment illustrated, the elastically deformable nature of the flange 26 is obtained by virtue of the shape of the connecting portion 26c, the thickness of this portion and the presence of the corrugation 44. In a variant, however, it may be possible to avoid rippling.

In the exemplary embodiment illustrated in FIG. 4, in which the identical elements bear the same references, the external lateral face 36 of the seal comprises a plurality of annular ribs 50 extending outwards in the direction of the flange 26 sealing. The bearing portion 26b of the flange is mounted axially 20 abutting against the ribs 50. The ribs 50 extend from the outer side face 36 and axially against the internal lateral face 40 of the flange. The ribs 50 are concentric and identical to each other. In the exemplary embodiment illustrated, the ribs 50 are six in number. The ribs 50 are here regularly spaced relative to each other in the radial direction. The ribs 50 are integral with the seal 32, i.e., one-piece. The ribs 50 extend axially. In the exemplary embodiment illustrated, the free end of each rib 50 preferably has a triangular shape in cross section so as to reduce the frictional torque between the seal 22 and the flange 26. An annular space 52 is delimited radially between each pair of successive ribs 50. The space 52 is delimited axially 3029993 11 by the bearing portion 26b of the flange and the external side face 36 of the seal. At least one lubricant (not shown), for example grease, is disposed within each space 52. The sealing in the area of contact of the flange 26 against the seal 22 is improved by the presence lubricant located within each of the spaces 52 and forming an annular bead. In the illustrated embodiment, the ribs 50 are formed on the outer side face 36 of the seal and bear against the bearing portion 26b of the flange. Alternatively, it could be possible to provide an inverted arrangement, namely ribs formed on the bearing portion 26b of the flange and bearing axially against the outer side face 36 of the seal. Compared to the first example illustrated, the embodiment of Figure 5, in which the identical elements bear the same references, differs only in the design of the flanges 60, 62 sealing the bearing. The mounting of each flange 60, 62 against the inner ring 16 and the seal 22, 24 associated is identical to that described in the first embodiment. The relative arrangement of each flange 60, 62 with respect to the associated seal 22, 24 differs only in that said flange is axially mounted in abutment against the outer lateral face of the seal near the inner sealing portion. of the seal. The flanges 60, 62 being identical in this embodiment, here will be described only one of them. The flange 60 is made in three separate pieces. The flange 60 comprises an annular fixing portion 64 mounted axially bearing against the front surface 16c of the inner ring, a bearing portion 66 on the ring-shaped seal 22 in axial contact with the outer side face 36. said seal, and a support portion 68 of said bearing portion. The fixing portion 64 has a radial shape and forms an inner portion of the flange. The bearing portion 66 forms an outer portion or end of said flange. In the exemplary illustrated embodiment, the bearing portion 66 has an axially concave curved shape on the outer side and axially convex on the inner side. The bearing portion 66 is in the form of a cup. The bearing portion 66 is mounted axially in contact with the external lateral face 36 of the seal. Only the bearing portion 66 of the flange is mounted in contact against the seal 22. The fixing portion 64 and the bearing portion 66 are each made of a rigid material, for example metal material advantageously from a sheet metal flank by cutting and stamping. Alternatively, the fixing portion 64 and the bearing portion 66 could each be made of another rigid material, for example synthetic material such as polyamide. The support portion 68 extends between the fastening portions 64 and bearing portions 66. The support portion 68 forms a connecting portion connecting the attachment and support portions 64 and 66. The support portion 68 covers the large-diameter edge of the fastening portion 64 and the outer lateral face of the bearing portion 66. The inner side face of the bearing portion 66 comes into axial contact against the outer side face 36 of the seal.

The support portion 68 is shaped to be flexible and elastically deformable in the axial direction. The connecting portion 68 extends inward towards the seal 22. In the exemplary embodiment illustrated, the support portion 68 has a curved shape concave axially on the outer side and 25 convex axially on the inner side. The support portion 68 is overmolded or vulcanized on the fastening portion 64 and the bearing portion 66. The support portion 68 is made of a flexible material, for example an elastomer such as a nitrile rubber or thermoplastic elastomer.

The support portion 68 is deformed axially outwardly of the bearing by the contact between the bearing portion 66 and the seal 22. The support portion 68 is deformed against its own resilience. The flange 26 is prestressed axially by the contact with the seal 22. In response to the deformation of the bearing portion 66, it exerts a permanent axial prestressing force on the seal 22. In the exemplary embodiments illustrated, each sealing flange is fixed on one of the front surfaces of the inner ring. Alternatively, it could be possible to provide the fixing of each flange inside an annular groove in the bore of the inner ring, for example by crimping. In the exemplary embodiments illustrated, each seal 10 comprises two parts, namely a reinforcing insert and a seal attached to this insert and provided with at least one friction lip cooperating with the inner ring to form a dynamic seal. Alternatively, the gasket could comprise only one or more labyrinth type lips cooperating with the inner ring. Alternatively, it may still be possible to provide a seal comprising a single portion, namely the reinforcing insert or the seal. In the exemplary embodiments illustrated, the sealing flange 20 is fixed on the inner ring and the associated seal is fixed on the outer ring. Alternatively, it could be possible to provide an inverted arrangement with the seal attached to the inner ring and the associated flange fixed on the outer ring.

Claims (14)

REVENDICATIONS1. Rolling bearing comprising an outer ring (14), an inner ring (16), at least one row of rolling elements (18) arranged radially between the rings, at least one sealing gasket (22) fixed on one rings (14) and cooperating with the other ring (16), and at least one flange (26; 60) sealing attached to said other ring (16), characterized in that said flange (26; 60) d at least partially elastically deformable in the axial direction and comprises at least one bearing portion (26b; 66) mounted axially in contact against an external lateral face (36) of said seal, said sealing flange being axially deformed by axial contact between said sealing gasket (22) and said bearing portion (26b; 66). Bearing according to claim 1, wherein said sealing flange (26; 60) comprises a fixing portion (26a; 64) for fixing the flange to said other ring (16) and a connecting portion (26c; 68) connecting said fixing portion and said bearing portion (26b; 66), at least said connecting portion being elastically deformable in the axial direction. The bearing of claim 2, wherein said connecting portion (26c; 68) extends inwardly toward the seal (22). Bearing according to claim 2 or 3, wherein said connecting portion (26c; 68) has a curved shape. 5. Bearing according to any one of the preceding claims, wherein said seal comprises at least one seal (32) defining the outer side face (36). 6. Bearing according to claim 5, wherein said seal (32) is made of a flexible material and at least said bearing portion (26b; 66) of the sealing flange is made of a rigid material. 3029993 15 7. Bearing according to claim 6, wherein at least said bearing portion (26b; 66) of the sealing flange is made of a metallic material. 8. Bearing according to any one of the preceding claims, wherein the connecting portion (68) is made of a flexible material. Bearing according to any one of the preceding claims, wherein said bearing portion (26b; 66) of the sealing flange has a convex shape axially on the side of said seal (22). 10.A bearing according to any one of the preceding claims, wherein said bearing portion (26b; 66) of the sealing flange forms an end portion of said flange. 11. A bearing as claimed in any one of the preceding claims, wherein the outer side face (36) of said seal is axially offset from the inner side of the bearing relative to a front surface (14c) of said ring. 12.A bearing according to any one of the preceding claims, wherein said sealing flange is mounted axially bearing directly against a front surface (14c) of said ring. 13. A deck as claimed in any one of the preceding claims, wherein said sealing flange (26) comprises at least one corrugation (44) distinct from said axially extending bearing portion (26b). 14.A bearing according to any one of the preceding claims, wherein the outer side face (36) of said seal comprises at least two annular ribs (50) against which said bearing portion (26b; ) of the sealing flange, at least one annular space (52) closed being defined by said flange and said ribs and within which is disposed at least one lubricant.