Rolling bearing, notably large-diameter rolling bearing

Abstract

A rolling bearing provides an inner ring and an outer ring concentrically about a rotation axis X-X′ running in an axial direction, and at least first and second axial bearings each axially disposed between the inner ring and the outer ring and each having at least one row of rolling elements, the first and second axial bearings being spaced apart from each other in the axial direction. The rolling bearing further provides only one radial bearing radially disposed between the inner ring and the outer ring and having at least one row of rolling elements. The radial bearing is disposed between an outer raceway located on the inner ring and an inner raceway located on the outer ring.

Claims

1. A rolling bearing comprising: an inner ring and an outer ring arranged concentrically about a rotation axis running in an axial direction, a first axial bearing and a second axial bearing each axially disposed between the inner ring and the outer ring and each having a row of axial bearing rolling elements, the first axial bearing and the second axial bearing being spaced apart from each other in the axial direction, and a radial bearing radially disposed between the inner ring and the outer ring, the radial bearing having a row of radial bearing rolling elements, wherein the radial bearing is disposed between an outer raceway located on the inner ring and an inner raceway located on the outer ring, and wherein the radial bearing is radially spaced from the first axial bearing and the second axial bearing such that the radial bearing does not overlap with either the first axial bearing or the second axial bearing.

2. The rolling bearing according to claim 1, wherein the radial bearing is axially located between the first axial bearing and the second axial bearing.

3. The rolling bearing according to claim 1, wherein the inner ring comprises an annular groove opening in a radial direction towards the outer ring and into which a protruding nose of the outer ring is located.

4. The rolling bearing according to claim 3, wherein the protruding nose comprises a protruding nose projection and the inner ring comprises an inner ring projection, and wherein the protruding nose projection and the inner ring projection engage behind one another in the radial direction such that the outer raceway for the radial bearing is located on the inner ring projection and the inner raceway for the radial bearing is located on the protruding nose projection.

5. The rolling bearing according to claim 4, wherein at least the annular nose projection has an L-shape with a radial portion and an axial portion.

6. The rolling bearing according to claim 3, wherein the first axial bearing and the second axial bearing are disposed axially on each side of the protruding nose.

7. The rolling bearing according to claim 1, wherein the outer ring comprises an annular groove opening in a radial direction towards the inner ring and into which a protruding nose of the inner ring is located.

8. The rolling bearing according to claim 7, wherein the protruding nose comprises a protruding nose projection and the outer ring comprises an outer ring projection, and wherein the protruding nose projection and the outer ring projection engage behind one another in the radial direction such that the outer raceway for the radial bearing is located on the protruding nose projection and the inner raceway for the radial bearing is located on the outer ring projection.

9. The rolling bearing according to claim 8, wherein at least the annular nose projection has an L-shape with a radial portion and an axial portion.

10. The rolling bearing according to claim 7, wherein the first axial bearing and the second axial bearing are disposed axially on each side of the protruding nose.

11. The rolling bearing according to claim 1, wherein the inner ring is divided in the axial direction into a support part and a holding part secured together, the outer raceway for the radial bearing being located on the support part, wherein the first axial bearing is axially disposed between the support part and the outer ring, and wherein the second axial bearing being axially disposed between the holding part and the outer ring.

12. The rolling bearing according to claim 1, wherein the outer ring is divided in the axial direction into a support part and a holding part secured together, the outer raceway for the radial bearing being located on the support part, wherein the first axial bearing is axially disposed between the support part and the inner ring, and wherein the second axial bearing being axially disposed between the holding part and the inner ring.

13. A rolling bearing comprising: an inner ring and an outer ring arranged concentrically about a rotation axis running in an axial direction, a first axial bearing and a second axial bearing each axially disposed between the inner ring and the outer ring and each having a row of axial bearing rolling elements, the first axial bearing and the second axial bearing being spaced apart from each other in the axial direction, and a radial bearing radially disposed between the inner ring and the outer ring, the radial bearing having a row of radial bearing rolling elements, the radial bearing is disposed between an outer raceway located on the inner ring and an inner raceway located on the outer ring, the inner ring defines a groove having a first groove portion and a second groove portion, the outer ring, when viewed in cross-section, comprises a radially elongated section formed by a protruding nose and an L-shaped projection located radially inwardly from the protruding nose, the first groove portion containing the protruding nose, the first axial bearing, and the second axial bearing therein, the second groove portion containing the L-shaped projection and the radial bearing therein, and wherein the radial bearing is located radially inwardly from the first groove portion and is radially spaced from the first groove portion by a projection formed by the inner ring.

14. The rolling bearing according to claim 13, wherein the radial bearing is axially located between the first axial bearing and the second axial bearing.

15. The rolling bearing according to claim 13, wherein the first axial bearing and the second axial bearing are disposed axially on each side of the protruding nose.

16. The rolling bearing according to claim 13, wherein the inner ring is divided in the axial direction into a support part and a holding part secured together, the outer raceway for the radial bearing being located on the support part, wherein the first axial bearing is axially disposed between the support part and the outer ring, and wherein the second axial bearing being axially disposed between the holding part and the outer ring.

17. A rolling bearing comprising: an inner ring and an outer ring arranged concentrically about a rotation axis running in an axial direction, a first axial bearing and a second axial bearing each axially disposed between the inner ring and the outer ring and each having a row of axial bearing rolling elements, the first axial bearing and the second axial bearing being spaced apart from each other in the axial direction, and a radial bearing radially disposed between the inner ring and the outer ring, the radial bearing having a row of radial bearing rolling elements, wherein the radial bearing is disposed between an outer raceway located on the inner ring and an inner raceway located on the outer ring, the outer ring defines a groove having a first groove portion and a second groove portion, the inner ring, when viewed in cross-section, comprises a radially elongated section formed by a protruding nose and an L-shaped projection located radially outwardly from the protruding nose, the first groove portion containing the protruding nose, the first axial bearing, and the second axial bearing therein, the second groove portion containing the L-shaped projection and the radial bearing therein, and wherein the radial bearing is located radially outwardly from the first groove portion and is radially spaced from the first groove portion by a projection formed by the outer ring.

18. The rolling bearing according to claim 17, wherein the radial bearing is axially located between the first axial bearing and the second axial bearing.

19. The rolling bearing according to claim 17, wherein the first axial bearing and the second axial bearing are disposed axially on each side of the protruding nose.

20. The rolling bearing according to claim 17, wherein the outer ring is divided in the axial direction into a support part and a holding part secured together, the inner raceway for the radial bearing being located on the support part, wherein the first axial bearing is axially disposed between the support part and the inner ring, and wherein the second axial bearing being axially disposed between the holding part and the inner ring.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The present invention and its advantages will be better understood by studying the detailed description of specific embodiments given by way of non-limiting examples and illustrated by the appended drawings on which:

(2) FIG. 1 is a partial cross-section of a rolling bearing according to a first example of the invention, and

(3) FIG. 2 is a partial cross-section of a rolling bearing according to a second example of the invention.

DETAILED DESCRIPTION OF THE INVENTION

(4) The rolling bearing 10 as illustrated on FIG. 1 is a large-diameter rolling bearing comprising a first ring 12 and an second ring 14. In the illustrated example, the first ring 12 is the inner ring of the rolling bearing whereas the second ring 14 is the outer ring. The rolling bearing 10 may for example be used in a tunnel boring machine, a wind turbine or any other applications using a large diameter rolling bearing.

(5) The inner and outer rings 12, 14 are concentric and extend axially along the bearing rotation axis X-X′ which runs in an axial direction.

(6) The rolling bearing 10 also comprises first and second axial bearings 16, 18 arranged axially between the inner and outer rings 12, 14, and a radial bearing 20 arranged radially between the rings.

(7) The inner ring 12 comprises an annular groove 22 opening in a radial direction outwardly towards the outer ring 14. The inner ring 12 comprises an outer cylindrical surface 12a from which the groove 22 is formed. The inner ring 12 further comprises two opposite radial frontal surfaces 12b, 12c which axially delimit the outer surface 12a of the ring.

(8) The outer ring 14 comprises an annular protruding lobe or nose 24 engaging into the annular groove 22 of the inner ring. The nose 24 extends radially inwards.

(9) The first and second axial bearings 16, 18 are arranged axially between the nose 24 of the outer ring and the groove 22 of the inner ring. The radial bearing 20 is arranged axially between the nose 24 of the outer ring and the groove 22 of the inner ring.

(10) The first and second axial bearings 16, 18 are spaced apart from each other in the axial direction. The first and second axial bearings 16, 18 are disposed on each side of the nose 24 of the outer ring. The rotation axes of the axial bearings 16, 18 are parallel one relative to another and perpendicular to the rotation axis X-X′ of the roller bearing 10.

(11) In the illustrated example, the axial bearing 16, 18 comprises a row of axial cylindrical rollers 16a, 18a having a rotation axis 16b, 18b perpendicular to the rotation axis X-X′ of the roller bearing 10. The axial rollers 16a, 18a roll on raceways located on the groove 22 of the inner ring and on the nose 24 of the outer ring.

(12) A first flank 22a of the groove and a first flank 24a of the nose 24 axially facing the first flank 22a delimit the raceways for the axial rollers 16a. A second flank 22b of the groove and a second flank 24b of the nose axially facing the second flank 22b delimit the raceways for the axial rollers 18a. The opposite first and second flanks 22a, 22b delimit axially the groove 22 of the inner. Similarly, the opposite first and second flanks 24a, 24b here delimit axially the nose 24 of the outer ring. The first and second axial bearings 16, 18 come into contact with the opposite flanks 24a, 24b of the protruding nose 24.

(13) In the illustrated example, the axial length of the rollers 16a of the first axial bearing is larger than the one of the rollers 18a of the second axial bearing. Alternatively, the axial length of the rollers 16a may be smaller than, or may be equal to, the one of the rollers 18a.

(14) The nose 24 of the outer ring is provided with an annular projection 26 extending inwards. The projection 26 has an L-shape. The projection 26 comprises a radial portion 26a extending radially inward from the nose 24, and a free axial portion 26b extending a small-diameter edge of the radial portion.

(15) In the illustrated example, the outer ring 14 is made in one part. Alternatively, the outer ring 14 may be divided in the axial direction in at least two separate parts secured together. In another variant, the nose 24 may be made separately from the main part of the outer ring. In the illustrated example, a toothing is provided on the outer ring 14.

(16) The inner ring 12 is divided in the axial direction in two separate parts, a support part 28 and a holding part 30 which are secured together. The support part 28 and the holding part 30 axially bear one against the other. In the illustrated example, passage holes 32 are provided on the support and holding parts 28, 30 which permit the fastening of these two part by bolts.

(17) The support part 28 and the holding part 30 of the inner ring delimit together the groove 22. The first flank 22a, which delimits on the inner ring 12 the raceway for the axial bearing 16, is located on the support part 28. The second flank 22a delimiting on the inner ring 12 the raceway for the axial bearing 18 is located on the holding part 30.

(18) The support part 28 of the inner ring comprises an annular axial projection 34 extending axially towards the holding part 30 while remaining axially distant. The projection 34 axially faces the radial portion 26a of the projection 26 of the outer ring. The projection 34 radially surrounds the axial portion 26b of the projection 26. The projection 34 and the axial portion 26b of the projection 26 are engaged behind one another and spaced in the radial direction. The radial portion 26a of the projection 26 is axially disposed between the support part 28 and the holding part 30.

(19) Between the projection 34 of the inner ring and the projection 26 of the nose 24 of the outer ring, there is arranged the radial bearing 20. More precisely, the radial bearing 20 is arranged radially between the projection 34 and the axial portion 26b of the projection 26.

(20) The projection 34 of the inner ring delimits an outer raceway 36 for the radial bearing 20. The axial portion 26b of the projection 26 of the outer ring delimits an inner raceway 38 for the radial bearing. The bore of the projection 34 delimits the outer raceway 36. The outer surface of the axial portion 26b of the projection delimits the inner raceway 38. The outer raceway 36 radially faces the inner raceway 38. The radial bearing 20 is radially disposed between the outer raceway 36 delimited on the inner ring 12 and the inner raceway 38 delimited on the outer ring 14.

(21) The rotation axis of the radial bearing 20 is coaxial with the rotation axis X-X′ of the roller bearing 10. In the illustrated example, the radial bearing 20 comprises a row of radial cylindrical rollers 20a having a rotation axis 20b parallel to the rotation axis X-X′. The radial rollers 20a roll on the outer and inner raceways 36, 38 located on the inner and outer rings.

(22) The radial bearing 20 is radially offset inwards with respect to the first and second axial bearings 16, 18. The radial bearing 20 is axially located between the first and second axial bearings 16, 18.

(23) Otherwise, as previously mentioned, in this illustrated example, the first ring of the rolling bearing is the inner ring 12 whereas the second ring is the outer ring 14.

(24) As an alternative, it could be possible to provide a reversed arrangement with the first ring forming the outer ring 12 and the second ring forming the inner ring 14 as shown on FIG. 2, in which identical parts are given identical references. In this second example, the groove 22 formed on the outer ring 12 opens radially inwards and the nose 24 of the inner ring extends radially outwards.

(25) The axial portion 26b of the projection 26 of the inner ring delimits the outer raceway 36 for the radial bearing 20. The projection 34 of the outer ring delimits the inner raceway 38 for the radial bearing 20. More precisely, the bore of the axial portion 26b of the projection delimits the outer raceway 36. The outer surface of the projection 34 delimits the inner raceway 38. In this embodiment, the outer raceway 36 for the radial bearing is still located on the inner ring 12, and the inner raceway 38 for the radial bearing is located on the outer ring 14. The radial bearing 20 is radially offset outwards with respect to the first and second axial bearings 16, 18.