WO2013062904A1

WO2013062904A1 - Roller separator for spherical roller bearings

Info

Publication number: WO2013062904A1
Application number: PCT/US2012/061308
Authority: WO
Inventors: Mark A. Joki
Original assignee: The Timken Company
Priority date: 2011-10-25
Filing date: 2012-10-22
Publication date: 2013-05-02

Abstract

A spherical roller bearing (56, 72) includes an outer ring (20), an inner ring (24), and a plurality of rollers (14) positioned between the outer and inner rings and arranged in a row. The bearing also includes a first separator (10) positioned between adjacent first and second rollers in the row. The first separator includes a first plurality of contact pads (44) that engage the first roller, and a second plurality of contact pads that engage the second roller for maintaining separation and spacing of the first and second rollers. The bearing further includes a second separator (10) positioned between adjacent third and fourth rollers in the row. The second separator includes a first plurality of contact pads (44) that engage the third roller, and a second plurality of con- tact pads (44) that engage the fourth roller for maintaining separa- tion and spacing of the third and fourth rollers. The separators (10) are movable independently of each other.

Description

ROLLER SEPARATOR FOR SPHERICAL ROLLER BEARINGS

FIELD OF THE INVENTION

[0001] The present invention relates to bearings, and more particularly to spherical roller bearings.

BACKGROUND OF THE FNVENTION

[0002] FIG. 1 illustrates a typical prior-art spherical roller bearing 5 including an inner ring 1, an outer ring 2, and rollers 3 arranged in two rows and positioned between the outer ring 2 and the inner ring 1. A single or unitary cage 4 is utilized to maintain the separation of the rollers 3 in each of the rows. As the spherical roller bearings 5 increase in size (e.g., up to 300mm or larger), the cost of machining the cage 4 to accommodate rollers 3 becomes a significant portion of the total cost of the bearing 5.

SUMMARY OF THE INVENTION

[0003] The present invention provides, in one aspect, a spherical roller bearing including an outer ring, an inner ring, and a plurality of rollers positioned between the outer and inner rings and arranged in a row about a central axis of the outer and inner rings. The bearing also includes a first separator positioned between adjacent first and second rollers in the row. The first separator includes a first plurality of contact pads that engage the first roller, and a second plurality of contact pads that engage the second roller for maintaining separation and spacing of the adjacent first and second rollers. The bearing further includes a second separator positioned between adjacent third and fourth rollers in the row. The second separator includes a first plurality of contact pads that engage the third roller, and a second plurality of contact pads that engage the fourth roller for maintaining separation and spacing of the adjacent third and fourth rollers. The first and second separators are movable independently of each other.

[0004] The present invention provides, in another aspect, a method of manufacturing a spherical roller bearing. The method includes providing a plurality of differently sized outer rings, inner rings, and rollers, and arranging a first of the outer rings, a first of the inner rings, and a first set of the rollers in a first bearing configuration. The method also includes arranging a second of the outer rings, a second of the inner rings, and a second set of the rollers in a second bearing configuration, and positioning one of a plurality of substantially identical separators between each of the rollers in each of the first and second bearing configurations for maintaining separation and spacing of the rollers in the first and second bearing configurations.

[0005] Other features and aspects of the invention will become apparent by consideration of the following detailed description and accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

[0006] FIG. 1 is a perspective view of a prior-art spherical roller bearing.

[0007] FIG. 2 is a perspective view of a separator for use with a spherical roller bearing in accordance with a first embodiment of the invention.

[0008] FIG. 3 is a cross-sectional view of a spherical roller bearing in accordance with a second embodiment of the invention.

[0009] FIG. 4 is a cross-sectional view of a spherical roller bearing in accordance with a third embodiment of the invention.

[0010] FIG. 5 is a cross-sectional view of an assembly basket and plate for use in assembling any of the spherical roller bearings of FIGS. 2-4.

[0011] Before any embodiments of the invention are explained in detail, it is to be understood that the invention is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the following drawings. The invention is capable of other embodiments and of being practiced or of being carried out in various ways. Also, it is to be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting.

DETAILED DESCRIPTION

[0012] FIG. 2 illustrates a separator 10 and a spherical roller 14 for use in a spherical roller bearing in accordance with a first embodiment of the invention. Such a bearing may include an outer ring 20, an inner ring 24 at least partially positioned within the outer ring 20, and the rollers 14 positioned between the inner and outer rings 24, 20 (see also FIG. 3). The inner ring 24 includes two spaced, concave raceways 28 arranged in a parallel or side -by-side manner, and the outer ring 20 includes a single contiguous inner raceway 32 spanning the width of the outer ring 20. The rollers 14 are positioned between the inner and outer rings 24, 20 and are arranged in spaced, parallel first and second rows 36, 40 about a central axis 42 of the inner and outer rings 24, 20 such that the rollers 14 in each of the rows 36, 40 are in facing relationship with each other.

[0013] With reference to FIG. 2, a separator 10 is positioned between adjacent rollers

14 in each of the rows 36, 40 to maintain separation and spacing of the rollers 14 in each of the rows 36, 40. As such, within each of the rows 36, 40, the rollers 14 and the separators 10 are arranged in an alternating manner in which the separators 10 may be movable

independently of each other. In other words, the separators 10 within each of the rows 36, 40 are not structurally interconnected, which would otherwise prohibit relative movement of one of the separators 10 relative to another. Each of the separators 10 includes a first plurality of contact pads 44 engaged with an adjacent first roller 14 and a second plurality of contact pads 44 engaged with a second adjacent roller 14 (not shown). In the illustrated construction of the separator 10, the contact pads 44 on each side of the separator 10 are arranged in a substantially rectangular pattern in a grouping of four contact pads 44. Alternatively, the contact pads 44 may be arranged in a triangular pattern in a grouping of three contact pads 44.

[0014] With continued reference to FIG. 2, each of the contact pads 44 includes a contact region 48, schematically illustrated as a discrete point, over which the contact pad 44 is engaged with a discrete portion of an adjacent roller 14. However, it should be understood that depending upon the particular sizing of the rollers 14, the inner ring 24, and the outer ring 20, the contact region 48 may occupy only a small portion of the surface area of each of the contact pads 44, or the contact region 48 may occupy up to the entire surface area of each of the contact pads 44. Each of the contact pads 44 may include one or more non-planar surfaces collectively defined by a plurality of contiguous, empirically determined contours, any one or a grouping of which may be employed as a contact region 48. Alternatively, each of the contact pads 44 may include one or more planar surfaces in addition to the non-planar surfaces, or in place of the non-planar surfaces. The separators 10 are made from a molded polymer material (e.g., polyetheretherketone or PEEK, polyamides or nylon, etc.). Alternatively, the separators 10 may be made from a metal using a casting, sintering, or injection molding process.

[0015] The contact pads 44 are shaped to accommodate rollers 14 of different sizes.

The separator 10 is therefore a common component that is usable in multiple spherical roller bearing configurations having different sized rollers 14, inner rings 24, and outer rings 20. For example, the same separators 10 may be employed with first and second bearing configurations having differently sized inner rings 24 and rollers 14, but the same size outer rings 20. Alternatively, the same separators 10 may be employed with first and second bearing configurations having differently sized rollers 14 and outer rings 20, but the same size inner rings 24. Further, the same separators 10 may be employed with first and second bearing configurations having differently sized rollers 14, outer rings 20, and inner rings 24.

[0016] With reference to FIG. 2, the contact regions 48 of each of the separators 10 are generally spaced from each other by a longitudinal dimension Di extending generally in a direction along the central axis 42 and a generally radial dimension D₂. The dimensions D_{l s} D₂ may vary depending upon the diameter and the length of the individual rollers 14 engaging the separator 10. For example, it is expected that each of the contact pads 44 may be shaped to provide multiple contact regions 48 upon which rollers 14 of different sizes and/or lengths are engageable. Having a common separator 10 that functions with rollers 14 of different sizes allows the assembly of more than one bearing configuration with the same separator 10, thereby reducing the cost of manufacturing each of the bearing configurations. Because of the advantage of a common separator 10, bearing geometry such as roller quantity, roller diameter, and/or raceway diameters may be adjusted slightly, in the order of less than 10%, to allow the use of a common separator 10 between various bearing sizes.

[0017] FIG. 3 illustrates a spherical roller bearing 56 in accordance with a second embodiment of the invention. Like components are identified with like reference numerals and will not be described again detail. The spherical roller bearing 56 additionally includes a floating spacer ring 52 positioned between the inner and outer rings 24, 20, and between the first and second rows 36, 40 of rollers 14. Particularly, the spacer ring 52 includes a first surface 60 in facing relationship with the first row 36 of rollers 14 and a second surface 64 in facing relationship with the second row 40 of rollers 14. [0018] The bearing 56 includes separators 66 that are substantially identical to the separators 10 described above and shown in FIG. 2. However, each of the separators 66 further includes a projection 68 that extends in a generally axial direction and is engageable with the spacer ring 52 to limit movement of the separators 66 in a direction generally along the central axis 42 (FIG. 3). For the separators 66 positioned between adjacent rollers 14 in the first row 36, the projections 68 are in facing relationship with the first surface 60 of the spacer ring 52. Likewise, for separators 66 positioned between adjacent rollers 14 in the second row 40, the projections 68 are in facing relationship with the second surface 64 of the spacer ring 52. The separators 66 are therefore identical, with the separators 66 disposed in the second row 40 being symmetrical to the separators 66 disposed in the first row 36 about a vertical axis (not shown) normal to the central axis 42. The projections 68 on the respective separators 66 and the spacer ring 52 engage and cooperate to maintain the alignment of the rollers 14 and the separators 66 within the first and second rows 36, 40. Alternatively, the spacer ring 52 may be engageable with each of the projections 68 of the respective separators 66 and the individual rollers 14 to control movement of the separators 66 and rollers 14 in a direction generally along the central axis 42. The separators 66 are functional in an otherwise identical manner as the separators 10 described above and shown in FIG. 2.

[0019] FIG. 4 illustrates a spherical roller bearing 72 in accordance with a third embodiment of the invention. Like components are identified with like reference numerals and will not be described again in detail. Rather than incorporating a floating spacer ring between the inner and outer rings 24, 20, the bearing 72 includes a snap ring 76 received within a circumferential groove 78 in the outer ring 20. As such, the snap ring 76 is secured to the outer ring 20 and prevented from moving along the central axis 42. The bearing 72 includes separators 80 that are substantially identical to the separators 10 described above and shown in FIG. 2. However, each of the separators 80 further includes a projection 84 that extends in both a generally axial direction and a generally radial direction, and that is engageable with the snap ring 78. The snap ring 76 serves to limit the articulation of the outer ring 20 relative to the inner ring 24. For instance, articulation could be limited to 1 degree or less. By limiting articulation, excessive misalignment between the inner and outer rings 24, 20, and thus potential loss of the rollers 14 and/or separators 80, is prevented.

Articulation may also be limited by the snap ring 76 interacting with the rollers 14 rather than the separators 80. [0020] FIG. 5 illustrates a method of assembling any of the spherical roller bearings described above. First, the inner ring 24 is positioned within the outer ring 20, and the outer ring 20 is tilted relative to the inner ring 24 to allow access to the outer raceways 28 near the top of the inner ring 24 from the frame of reference of FIG. 5. An assembly basket 88 having a concave, inner raceway 92 is positioned below the outer raceways 28 near the bottom of the inner ring 24 from the frame of reference of FIG. 5. The rollers 14 and separators 10 are placed in the assembly basket 88 in an alternating manner into the first and second rows 36, 40. The assembly basket 88 supports the rollers 14 and the separators 10 located on an underside of the inner ring 24, from the frame of reference of FIG. 5, that are otherwise unsupported by the outer ring 20 to prevent loss of the rollers 14 and separators 10 due to gravity. The rollers 14 and the separators 10 located on the top side of the inner ring 24, from the frame of reference of FIG. 5, are supported on the outer raceways 28 by the rollers 14 and separators 10 that are either directly supported by the assembly basket 88, or that are supported between the inner ring 24 and the outer ring 20. Optionally, at least one assembly plate 96 may be used to facilitate containment of the rollers 14 and separators 10 within the individual rows 36, 40.

[0021] Prior to loading the last rollers 14 of the first and second rows 36, 40, the assembly basket 88 is moved away from the inner ring 24 to create sufficient space for inserting the last few rollers 14. After all of the rollers 14 have been inserted, the assembly basket 88 is moved towards the inner ring 24, and held against the outer ring 20 as the outer ring 20 is pivoted toward alignment with the inner ring 24 to take the place of the inner raceway 92 of the assembly basket 88. The inner raceways 92, 32 on the assembly basket 88 and the outer ring 20, respectively, provide a substantially continuous surface to support the rollers 14 and the separators 10 while the inner and outer rings 24, 20 are being aligned. After the outer ring 20 has been aligned with the inner ring 24, the assembly basket 88 is removed from the spherical roller bearing, and the rollers 14 and separators 10 are positioned between and fully supported by the inner and outer rings 24, 20. Of course, should either of the spacer ring 52 or the snap ring 76 be incorporated with the bearing, it would be positioned on the inner ring 24 at some time before or during placement of the rollers 14 in the respective rows 36, 40. Particularly the snap ring 76 would be radially compressed prior to tilting the outer ring 20 into alignment with the inner ring 24. After the outer ring 20 is aligned with the inner ring 24, the snap ring 76 may be released to permit the snap ring 76 to expand radially into the circumferential groove 78. [0022] Various features of the invention are set forth in the following claims.

Claims

CLAIMS What is claimed is:

1. A spherical roller bearing comprising:

an outer ring;

an inner ring;

a plurality of rollers positioned between the outer and inner rings and arranged in a row about a central axis of the outer and inner rings;

a first separator positioned between adjacent first and second rollers in the row and including a first plurality of contact pads that engage the first roller and a second plurality of contact pads that engage the second roller for maintaining separation and spacing of the adjacent first and second rollers; and

a second separator positioned between adjacent third and fourth rollers in the row and including a first plurality of contact pads that engage the third roller and a second plurality of contact pads that engage the fourth roller for maintaining separation and spacing of the adjacent third and fourth rollers,

wherein the first and second separators are movable independently of each other.

2. The spherical roller bearing of claim 1, wherein the plurality of rollers are arranged in a first row, and wherein the spherical roller bearing further includes a second plurality of rollers positioned between the outer and inner rings and arranged in a second row.

3. The spherical roller bearing of claim 2, further comprising:

a third separator positioned between adjacent first and second rollers in the second row and including a first plurality of contact pads that engage the first roller in the second row and a second plurality of contact pads that engage the second roller in the second row for maintaining separation and spacing of the adjacent first and second rollers in the second row; and

a fourth separator positioned between adjacent third and fourth rollers in the second row and including a first plurality of contact pads that engage the third roller in the second row and a second plurality of contact pads that engage the fourth roller in the second row for maintaining separation and spacing of the adjacent third and fourth rollers in the second row, wherein the first, second, third, and fourth rollers in the first row are in facing relationship with the first, second, third, and fourth rollers in the second row, respectively.

4. The spherical roller bearing of claim 3, further comprising a spacer ring positioned between the first and second rows.

5. The spherical roller bearing of claim 4, wherein each of the first and third separators is engageable with the spacer ring to limit movement of the first and third separators in a direction generally along the central axis.

6. The spherical roller bearing of claim 5, wherein each of the first and third separators includes a projection that is engageable with the spacer ring to limit movement of the first and third separators in a direction generally along the central axis.

7. The spherical roller bearing of claim 6, wherein one of the outer and inner rings includes a surface having a circumferential groove.

8. The spherical roller bearing of claim 7, wherein the spacer ring is received within the circumferential groove.

9. The spherical roller bearing of claim 8, wherein the spacer ring is configured as a snap ring.

10. The spherical roller bearing of claim 9, wherein the snap ring, by engaging the projection on each of the first and third separators, limits articulation of the inner ring relative to the outer ring.

11. The spherical roller bearing of claim 1 , wherein the first and second separators are made of a polymer material.

12. The spherical roller bearing of claim 1, wherein the first and second plurality of contact pads each have a non-planar shape.

13. The spherical roller bearing of claim 1, wherein the first and second separators are substantially identical.

14. A method of manufacturing a spherical roller bearing, the method comprising: providing a plurality of differently sized outer rings, inner rings, and rollers; arranging a first of the outer rings, a first of the inner rings, and a first set of the rollers in a first bearing configuration;

arranging a second of the outer rings, a second of the inner rings, and a second set of the rollers in a second bearing configuration; and

positioning one of a plurality of substantially identical separators between each of the rollers in each of the first and second bearing configurations for maintaining separation and spacing of the rollers in the first and second bearing configurations.

15. The method of claim 14, further comprising arranging the first set of rollers in a first row and a second row about a central axis of the first outer ring and the first inner ring.

16. The method of claim 15, further comprising positioning a spacer ring between the first and second rows.

17. The method of claim 16, further comprising providing each of the separators with a projection that is engageable with the spacer ring to limit movement of the separators in a direction generally along the central axis.

18. The method of claim 17, further comprising providing a circumferential groove within a surface disposed on one of the first outer ring and the first inner ring.

19. The method of claim 18, further comprising positioning the spacer ring within the circumferential groove for limiting articulation of the first inner ring relative to the first outer ring.

20. The method of claim 14, further comprising making the separators from a polymer material.

21. The method of claim 14, wherein arranging the first and second bearing configurations includes providing different sizes of the first and second inner rings, and the first and second sets of rollers in the first and second bearing configurations, respectively.

22. The method of claim 14, wherein arranging the first and second bearing configurations includes providing different sizes of the first and second outer rings, and the first and second sets of rollers in the first and second bearing configurations, respectively.

23. The method of claim 14, wherein arranging the first and second bearing configurations includes providing different sizes of the first and second outer rings, the first and second sets of rollers, and the first and second inner rings in the first and second bearing configurations, respectively.