FR2886694A1 - Rotation blocking device for a rolling bearing with an outer stationary race comprises a rotation blocking ring with a tongue provided with at least one surface in contact with a cutout in the bearing seat - Google Patents

Abstract

The rotation blocking device for a rolling bearing (1) with an outer stationary race (3) comprises a rotation blocking ring (10) with a tongue (12) provided with at least one surface in contact with a cutout in the bearing seat. Independent claims are also included for: (A) a bearing unit with the proposed rotation blocking device; (B) a machine with such a bearing unit.

Description

Anti-rotation device for rolling ring, and bearing and machine

associates.

  The present invention relates to the field of devices used to limit a possible rotation of a non-rotating race of a bearing relative to its housing. Such devices are generally called anti-rotation or anti-slip devices and are particularly used for bearings used in alternators.

  In this type of application, a rotor is rotatably mounted in a housing, inside which is fixed a stator, by means of two bearings of the type comprising a rotating inner ring, a non-rotating outer ring, and a row of rolling elements arranged between the rings. The inner rings of each of the bearings are mounted tightly on a bearing surface of the rotor, the outer rings being mounted in a housing of the housing provided for this purpose.

  The outer ring of one of the bearings is generally mounted in said housing with a sliding fit to allow a slight axial displacement of said ring relative to the housing.

  This adjustment can allow, on the one hand, to apply, via axially elastic washers, an axial prestressing force on the bearings, and, on the other hand, to overcome any axial dimensional variations of the housing due to thermal variations.

  In general, the outer rings of the bearings and their housings are made of materials of different types, for example steel and light alloy, such as aluminum. Due to the differential expansions of these two materials, the adjustment provided between the outer ring of a bearing and its housing can be modified, which can generate insufficient radial clamping between these two parts, or even a slight radial play.

  The internal friction torque of the bearing generated in particular by the viscosity of the lubricant used for said bearing, or by the friction of the bearing seals, combined with the decrease in clamping or the slight play between bearing and housing, can angular sliding of the outer ring in its housing and thus adversely affect the proper functioning of the alternator. It is therefore necessary to provide devices for limiting a possible rotation of the outer ring relative to its housing.

  For this purpose, US Pat. No. 5,785,433 discloses an antirotation ring for an open race ring at a point of its circumference and defined radially by inner and outer curved and eccentric surfaces with respect to each other. . The ring comprises a plurality of elastically deformable portions.

  The ring is mounted inside a groove formed on an outer cylindrical surface of the outer ring of the bearing, said groove being provided with an eccentric bottom relative to the geometric axis of said ring. When mounting the bearing within a housing, the elastically deformable portions protruding from the outer cylindrical surface of the outer ring radially come into contact with said housing.

  In operation, during a rotation of the outer ring of the bearing relative to the housing, the ring remains stationary in the groove by frictional contact of the deformable portions with the housing, which causes a wedging between the outer ring, the ring and the housing thus limiting the angular displacement of the outer ring relative to said housing.

  Such a ring has the disadvantage of comprising a plurality of elastically deformable portions, which must be narrowed during assembly of the bearing inside the housing, which complicates a little the mounting operation of the bearing in its housing, and also creates a risk of particles being wrenched off the deformable portions of the ring if it is made of plastic material, thus potentially generating pollution risks.

  In addition, the ring has a relatively complex shape that can be expensive.

  The present invention therefore aims to overcome these disadvantages by providing a anti-rotation device for reliable bearing, economical, and for easy mounting of the bearing.

  For this purpose, an anti-rotation device for a bearing is of the type provided with a rotating ring, a non-rotating ring comprising an annular groove formed on a cylindrical surface, and a row of rolling elements arranged between raceways of said rings, the bottom of said groove being eccentric with respect to the axis of the non-rotating ring.

  The device comprises an anti-rotation ring intended to be mounted in the groove and delimited radially by coaxial inner and outer cylindrical surfaces. The ring further comprises at least one radial projection forming a tongue intended to be mounted inside a cavity formed in a housing inside which the non-rotating ring is mounted, said tongue comprising at least one contact surface with the cavity so as to exert a radial force on said cavity during an angular displacement of the non-rotating ring relative to the housing.

  Such a device has the advantage of comprising a tongue mounted in a shape matching recess for providing particularly accurately and securely locking rotational ring unwinding relative to the housing.

  In addition, with the existence of such a cavity, the tongue does not interfere when mounting the bearing inside the housing, which significantly simplifies the assembly of the machine inside which the bearing is mounted and increases its operational safety.

  Furthermore, the design of a radially delimited ring by coaxial inner and outer surfaces makes it possible to obtain a particularly economical device.

  Preferably, the radial thickness of the ring is adapted so that the outer cylindrical surface of said ring is included in an area delimited radially between a bottom wall of the groove and the cylindrical surface of the non-rotating ring, when the tongue is centered on the deepest area of the groove.

  Such an arrangement thus makes it possible to limit any radial interference of the ring with the housing when the bearing is mounted inside said housing.

  Advantageously, the radial thickness of the ring is substantially less than the depth of the groove.

  The ring may be open on part of its circumference and / or extend angularly between 180 and 360.

  Preferably, the ring has a substantially constant axial dimension.

  The ring may advantageously be made of molded synthetic material.

  The ring may comprise a single tongue, so as to obtain a particularly economical device.

  Advantageously, the tongue and the ring are in one piece, which makes it possible to obtain a unitary assembly that can be handled and transported with risks of accidental separation of these particularly weak elements.

  The invention also relates to a bearing device provided with a rotating ring, a non-rotating ring comprising an annular groove formed on a cylindrical surface, the bottom of said groove being eccentric with respect to the axis of the non-rotating ring. -turning, a row of rolling elements disposed between the raceways of said rings, and an anti-rotation ring mounted in the groove.

  The ring is delimited radially by coaxial inner and outer cylindrical surfaces and further comprises at least one radial projection forming a tongue, intended to be mounted inside a cavity formed in a housing inside which the non-rotating ring is mounted, said tongue comprising at least one contact surface with the cavity so as to exert a radial force on said cavity during an angular displacement of the non-rotating ring relative to the housing.

  The invention also relates to a machine comprising a fixed part, a movable part, and at least one rolling device mounted between said parts and provided with a rotating ring, a non-rotating ring comprising an annular groove formed on a surface cylindrical, the bottom of said groove being eccentric with respect to the axis of the non-rotating ring, a row of rolling elements disposed between the raceways of said rings, and an anti-rotation ring mounted in the groove.

  The ring is delimited radially by coaxial inner and outer cylindrical surfaces, the ring further comprising at least one radial projection forming a tongue mounted inside a cavity formed in a housing of the fixed part to the inside which the non-rotating ring is mounted, said tongue comprising at least one contact surface with the cavity, so as to exert a radial force on said cavity during an angular displacement of the non-rotating ring relative to the housing.

  The present invention will be better understood on reading the detailed description of embodiments taken by way of non-limiting examples and illustrated by the accompanying drawings, in which: FIGS. 1 to 3 are perspective views of a bearing comprising an anti-rotation device according to one aspect of the invention; - Figure 4 is a schematic sectional view of the anti-rotation device of Figures 1 to 3; FIG. 5 is a diagrammatic view in axial section of the bearing of FIGS. 1 to 3; - Figure 6 is a schematic axial sectional view of the bearing of Figures 1 to 3 mounted on a shaft and provided with the anti-rotation device; FIG 7 is a partial sectional view along the axis VII-VII 20 of Figure 6; and FIGS. 8 to 10 are partial views of variant embodiments of the anti-rotation device of FIGS. 1 to 4.

  As can be seen in Figures 1 to 3 and 5, the bearing, referenced 1 as a whole, is of the single row deep groove ball type. It comprises an inner ring 2, an outer ring 3, between which are housed a row of rolling elements 4 made here in the form of balls, a cage 5 for holding the circumferential space of the rolling elements 4, and two seals. sealing 6 and 7 metal.

  The inner ring 2 is massive type. Solid ring means a ring whose shape is obtained by machining with chip removal (turning and / or grinding) from tubes, bars, forged blanks and / or rolled. The inner ring 2 comprises a bore 2a of cylindrical shape delimited by opposite radial lateral surfaces 2b and 2c, and an outer cylindrical surface 2d stepped from which is formed a toroidal circular groove 2e having in cross section a concave profile capable of forming a rolling path for the rolling elements 4, said groove being oriented outwards.

  The inner ring 2 also comprises, at the level of the outer cylindrical surface 2d and near the radial surfaces 2b and 2c, two annular grooves (not referenced) symmetrical to each other with respect to a plane passing through the center of the rolling elements 4.

  The outer ring 3, also of massive type, comprises an outer cylindrical surface 3a delimited by opposite radial lateral surfaces 3b and 3c, and a 3d stepped bore of generally cylindrical shape from which is formed a circular toroidal groove 3e having a cross-section a concave profile capable of forming a raceway for the rolling elements 4, said groove being oriented towards the inside.

  The outer ring 3 also comprises, at the bore 3d and near the radial surfaces 3b and 3c, two annular grooves (not referenced) symmetrical to each other with respect to a plane passing through the center of the rolling elements 4. Said grooves rings are radially opposite the annular grooves of the inner ring 2.

  Inside said grooves are mounted the seals 6 and 7. The seals 6 and 7 are thus arranged radially between the inner and outer rings 2, 3. The seal 6 is mounted axially between the rolling elements 4 and the radial surfaces 2b and 3b of the rings 2 and 3, the seal 7 being mounted axially between the rolling elements 4 and the radial surfaces 2c and 3c of said rings 2 and 3.

  The outer ring 3 also comprises an annular groove 8 formed at the outer cylindrical surface 3a and having, in cross section, a substantially rectangular profile. The annular groove 8 is here arranged axially substantially between the center of the rolling elements 4 and the radial surface 3b of the outer ring 3. The groove 8 with radial lateral faces comprises a bottom wall 8a annular cylindrical and eccentric with respect to a geometric axis 9 of the outer ring 3. Said outer ring 3 is here non-rotating, the inner ring 2 being rotating. Of course, it is also conceivable to provide a rotating outer ring and a non-rotating inner ring.

  The bearing 1 also comprises an anti-rotation ring 10, advantageously made of molded synthetic material, and mounted inside said groove 8. The ring 10 is open over part of its circumference.

  As illustrated more clearly in FIG. 4, the ring 10, made in one piece, is provided with a fastening portion 11, in the general shape of an arc of a circle delimited radially by internal and external cylindrical surfaces 1a. and 1lb coaxial annular, and an outgrowth or radial protrusion forming tab 12 and extending, in part, the outer surface 1 lb outwardly. The inner surface 1a is intended to be in radial contact with the bottom wall 8a of the groove 8 and has a radius of curvature substantially identical to that of the bottom of said groove.

  The fixing portion 11 thus has a substantially constant radial dimension, this dimension being preferably determined so that when the tongue is centered on the deepest zone of the groove, the outer surface 1 lb of the ring 10 does not exceed not radially from the cylindrical outer surface 3a of the outer ring 3. It is thus possible to design the ring 10 so that the radial dimension of the fastening portion 11 is less than or equal to the minimum depth of the groove 8. The portion fastener 11 also has a substantially constant axial dimension and approximately corresponding to the axial dimension of the groove 8.

  The fixing portion 11 extends circumferentially here about 200. Of course, it is also conceivable to provide a substantially different angular dimension, but is preferably greater than 180 to ensure a good snap of the ring 10 inside the groove 8.

  The tongue 12 is disposed substantially at a median plane of the fastening portion 11 and has a generally rectangular shape. The angular dimension of the tongue 12 is reduced relative to that of the fixing portion 11, and is for example between 10 and 15. The axial dimension of the tongue 12 is substantially equal to that of the fixing portion 11, its radial dimension being substantially greater than that of said portion 11, for example in a ratio of 5 to 1.

  In Figures 6 and 7, the bearing 1 is mounted on a shaft 13 of geometric axis 14 and within a body 15. The geometric axis 14 and the axis 9 of the outer ring 3 are merged.

  The body 15, of generally annular shape, comprises a first radial portion 15a disposed in the vicinity of the outer cylindrical surface of the shaft 13 and extending outwards, which is extended, from an upper end, by a second radial portion 15b extending outwardly. The second radial portion 15b has an axial dimension substantially greater than that of the first portion 15a and forms a bearing surface for the radial surface 3b of the outer ring 3 of the bearing 1. The second radial portion 15b is extended, from an upper end, by an axial portion 15c provided with a bore 15d inside which is housed the outer ring 3 of the bearing 1.

  The axial portion 15c of the body 15 also comprises a cavity 16 formed at the bore 15d, substantially in correspondence with the tongue 12 of the ring 10. The cavity 16 leaves a slight radial clearance 17 between a surface of external contact 12a of the tongue 12 and the axial portion 15c of the body 15.

  In alternative embodiments, it is also conceivable to provide a cavity 16 having in cross section a generally triangular shape, the tongue 12 being for example identical to that previously described (FIG. 8), or else in concordance with said cavity (Figure 9). It is also conceivable to provide, as shown in Figure 10, a cavity 16 having in cross section a profile in the form of a semicircle.

  Before mounting the bearing 1 inside the body 15, a first step is to arrange the ring 10 inside the groove 8 of the outer ring 3, so that the tongue 12 is centered in the zone of maximum depth of said groove 8. The outer surface 11b of the fastening portion 11 of the ring 10 is offset radially inwardly relative to the outer cylindrical surface 3a of the outer ring 3, only the tongue 12 being protruding radially outwardly from said outer surface 3a.

  Then, the inner ring 2 of the roll 1 is loaded onto the shaft 13, and the shaft is mounted inside the body 15 so that the tongue 12 of the ring 10 is housed inside the body. cavity 16 of the axial portion 15c. During the introduction of the bearing 1 within the axial portion 15c, the ring 10 does not interfere with the bore 15d, by design.

  In operation, if the outer ring 3 tends to rotate relative to the axial portion 15c of the body 15, the ring 10 remains angularly stationary by mechanical cooperation of the tongue 12 with the cavity 16. The bottom 8a of the groove 8 eccentric by relative to the axis 9 of the outer ring 3 radially moves the ring 10 towards the body 15, by camming effect, which causes the reduction of the operating clearance 17 until the surface 12a of the tongue 12 or in radial contact with the bottom of the cavity 16. The ring 10 is thus blocked radially, which causes an angular immobilization of the outer ring 3 of the bearing 1 and thus limits its rotation inside the body 15.

  The ring thus performs, in operation, an antirotation system of a ring relative to its housing particularly easy to assemble, effective, reliable and economical.

Claims (11)

  1-Anti-rotation device for a bearing of the type provided with a rotating ring (2), a non-rotating ring (3) comprising an annular groove (8) formed on a cylindrical surface, and a row of rolling elements (4) arranged between rolling paths of said rings, the bottom of said groove being eccentric with respect to the axis of the non-rotating ring, the device comprising a ring (10) anti-rotation intended to be mounted in the groove characterized in that the ring is delimited radially by coaxial inner and outer cylindrical surfaces, the ring further comprising at least one radial tongue projection (12) for mounting within a cavity formed in a housing inside which the non-rotating ring is mounted, said tongue comprising at least one contact surface with the cavity so as to exert a radial force on said cavity during an angular displacement the circumferential ring in relation to the housing.   2-Device according to claim 1, wherein the radial thickness of the ring (10) is adapted so that the outer cylindrical surface of said ring is included in a radially delimited area between a bottom wall (8a) of the groove and the cylindrical surface of the non-rotating ring, when the pin is centered on the deepest zone of the groove.   3-Device according to claim 2, wherein the radial thickness of the ring (10) is substantially less than the depth of the groove.   4-Device according to any one of the preceding claims, wherein the ring (10) is open on part of its circumference.   5-Device according to any one of the preceding claims, wherein the ring (10) extends angularly between 180 and 360.   6-Device according to any one of the preceding claims, wherein the ring (10) has a substantially constant axial dimension.   7-Device according to any one of the preceding claims, wherein the ring (10) is made of molded synthetic material.   8-Device according to any one of the preceding claims, wherein the ring (10) comprises a single tongue (12).   9-Device according to any one of the preceding claims, wherein the tongue and the ring are monobloc.   10-rolling device provided with a rotating ring (2), a non-rotating ring (3) comprising an annular groove (8) formed on a cylindrical surface, the bottom of said groove being eccentric with respect to the axis of the non-rotating ring, of a row of rolling elements (4) arranged between the rolling paths of said rings, and of an anti-rotation ring (10) mounted in the groove, characterized in that the ring is delimited radially by coaxial inner and outer cylindrical surfaces, the ring further comprising at least one radial tongue protrusion (12) for mounting within a cavity in a housing at the inside which the ringing ring is mounted, said tongue comprising at least one contact surface with the cavity so as to exert a radial force on said cavity during an angular displacement of the non-rotating ring relative to the housing.   11-Machine comprising a fixed part, a movable part, and at least one rolling device mounted between said parts and provided with a rotating ring (2), a non-rotating ring (3) comprising a groove (8) ring formed on a cylindrical surface, the bottom of said groove being eccentric with respect to the axis of the non-rotating ring, of a row of rolling elements (4) arranged between the rolling paths of said rings, and of an anti-rotation ring (10) mounted in the groove, characterized in that the ring is delimited radially by coaxial inner and outer cylindrical surfaces, the ring further comprising at least one radial tongue protrusion (12) mounted inside a cavity (16) formed in a housing of the fixed part inside which the non-rotating ring is mounted, said tongue comprising at least one contact surface with the cavity so as to exert a radial force on ladi the cavity during an angular displacement of the non-rotating ring relative to the housing.