GB2139712A

GB2139712A - Improved roller bearing

Info

Publication number: GB2139712A
Application number: GB08409349A
Authority: GB
Inventors: Peter Cameron
Original assignee: Individual
Current assignee: Individual
Priority date: 1983-05-06
Filing date: 1984-04-11
Publication date: 1984-11-14
Also published as: GB2139712B; GB8409349D0

Abstract

A roller bearing is disclosed which has an inner race (12) and an outer race (14). A cage (18) including cross-members (20) is disposed between the races and support rollers (22). The rollers (22) are supported so that they can move in a direction transverse to the longitudinal axis of the bearing by providing washers (38) having an axle (40) which is received in a recess (36) in the cage or is received between cross-members (20) of the cage. The rollers (22) are mounted on the axles (40). <IMAGE>

Description

SPECIFICATION Improved roller bearing This invention relates to roller bearings particularly for supporting heavy loads. As is well known roller bearings may be used to journal a shaft such as a vehicle axle or other heavy machinery. The rollers of such roller bearings may come in a variety of shapes such as cylindrical, tapered, barrel shaped, needle shaped, etc. and the roller bearings generally include a cage to maintain the rollers in their correct relative positions so thatthey do nottouch one another.

The objectofthe invention isto provide an improved roller bearing.

The invention provides a roller bearing having an inner race and an outer race, a cage for locating at least one roller between the inner race and the outer race, said cage including a roller retaining meansfor locating the roller relative to the cage so that the roller can move in a direction transverse to the longitudinal axis ofthe bearing, said retaining means comprising an axle holder having an axle, said roller being mounted on the axle for rotation aboutthe axle.

The distance between the races of a roller bearing can changedueto several factorsfor example deformation of rolling surfaces allowing a smaller gap under the inner race, temperature differentials of bearings parts and shaft misalignment, and deflection caused by load or imperfect workmanship. The roller retaining means of the invention allows a rollerto position itself in ideal position between the races and put a corrrespondingly less stress on the axles.

Furthermore it would also be simpler to fabricate the bearing as the rollers would automatically position themselves between the races with just the roller alignment to attend to when attaching the rollers to the cage.

Accordinglywiththe retainer of this invention the axle is free to move up and down in the recess to properly locate the roller between the races. The designseemsto be the most advantageous in the objectives towards the ease and economy of manufacture and to maximisethe load carrying capacity in relation to size ofthewhole bearing, that is, the ratio of roller lengths to total bearing length.

Preferably a plurality of recesses and retaining means are provided -- one fo r each end of each roller.

A preferred embodiment of the invention will be described with reference to the accompanying drawings in which: Figure lisa broken away perspective view of a bearing embodying the invention; Figure 2 is a detailed view showing the manner in which a roller is retained in the bearing; Figure 3 is a transverse cross-sectional view through the bearing; Figure 4 is an exploded view of a preferred roller retaining means; Figures 5 and 6 show second and third embodimentsofthe invention; Figure 7 is a view of a cage used in the invention; Figure8 is aviewalongthe line 8-8 of Figure 7; and Figures 9 and 10 show a fourth embodiment of the invention.

With referenceto Figures 1 and3a roller bearing 10 is shown which has an inner race 12 and an outer race 14. The inner race 12 is intheform of a shaftwhich isto rotate in the bearing. A shaft such as an axle of a vehicle or other heavy machinery may be connected to the shaftwhich forms the inner race or may comprise the inner race. The outer race 14 is in the form a cylinder open at both ends. Located in the space between the races 12 and 14 is a roller cage 16 comprised of two annular plates 18 (only one shown in Figure 1) and a plurality of cross members 20 coupled to and extending between the plates 18. Is should be noted that the other end of the bearing is identical to the end shown in Figure 1 and therefore need not be described in detail.

A plurality of rollers 22 are disposed between the races 12 and 14 and are in contact with the races 12 and 14. As seen in Figure 3the rollers 22 and cross member 20 alternate around the bearing.

In the embodiment of Figure 1 the inner and outer races 12 and 14extend out beyond the plates 18 and the annular plates 18 each have an inner and outer annularthrust bearing track 24 and 26 coupled therewith. Corresponding annular thrust bearing tracks 28 and 30 are connected to the inner race 12 and outer race 14 respectively by means of bolts 32 and nuts 34which prevent the tracks 28 and 30 from moving longitudinally outwardly. Thetracks 28 and 30 can also be connected to the inner and outer races in any other desired mannerto therebyfixthe tracks 28 and 30 to those races.

A plurality of small rolling elements, for example, tapered roller bearings (not shown) are located between the tracks 26 and 30 and tracks 24 and 28.

Thefourthrust bearings defined by the tracks 26,30 and 24,28 with the small tapered bearings therebetween, at each end ofthe track, act to prevent the rollers 22 and cage 16from moving longitudinallywith respect to the races when the bearing is under load and therefore allows the bearing to work efficiently and provide minimal resistance.

Referring nowto Figures 2,4,7 and 8 which show the roller retaining means for each roller 22 which comprises a plurality of recesses 36 in each annular plate 18. Figure 4A shows the retaining means assembled and Figure 4B shows an axle holder and axle (washer 38 and axle 40) separate from the bearing for sake of clarity. The diameter of the axle 40 can be any magnitudewithin acceptable limits and Figure4A shows a large diameter axle 40 and Figure 4B shows a relatively small diameterforthe axle 40. The square washer38 having the axle40 is adapted to beslidably received in the recess 36. Of course a recess 36 is provided in each plate 18foreach roller 22 and each recess 36 has a squa re washer 38 therein . The recesses 36 may extend all the way along the surface 42 of plates 18 as shown in Figure 7 or only part the way along the surface 42 of the plates 18 as shown in Figures 2 and 5. The ends of the rollers 22 are provided with recesses 47.The axle 40 has an annular bearing track 48 (not shown in Figure 4B) and the recess 47 is provided with an annulartrack50. The axle40 extends into recess 47 so that the tracks 48 and 50 are opposed to one another. A plurality of ball bearings 52 are arranged between the tracks 48 and 50 so that the rollers 22 can rotateabouttheirlongitudinal axis about axle 40. The washer 38 is able to slide in a direction perpendicular (as shown by arrow A) to the roller longitudinal axis, in recess 36.This enables the rollerto position themselves ideally between the inner and outer races 12 and 14 and therefore reduce stress on the roller axles. It also enables movementtransverse to the roller axis when the distance between the races 12 and 14 has changed dueto temperature variation, deformation ofthe rolling surfaces and misalignment due to manufacturing tolerances.

Figures 5 and 6 showsecond andthird embodiments of arranging the trust bearing between the races 12 and 14 and the cage 16. In Figure 6a portion of the plate 18 and the cross member20 is shown whereas in Figure 5 a roller 22 together with lugs36 etc. are shown. In the embodiment of Figure 5 races 12 and 14 are provided with cut-out portions 52 and 54 and the annular plate 18 is arranged between the cut-out portions 52 and 54 and is provided on its inner and outersurfaceswith a screw th read 56 and 58. The track30 is in the form of an annular ring having a screw thread on its inner surface 60 and is screwed onto the thread 58. The track 28 is a smaller annular ring and is provided with a screw thread on its outer surface 64 and screwed onto screwthread 56.Tapered bearings (not shown) are provided in the opposed grooves 25 formed in tracks 26 and 30 and 24 and 28. In this embodimentthetracks 26 and 28 are integral with the races 12 and 14with the groove 25 being formed in vertical walls 62 and 64 of the cut-out portion 52 and 54.

In Figure 6the tracks 26 and 24 are formed in the plates 18 by cutting the grooves 25 directly into the plates 18. The plates 18 are otherwise identical to those shown in Figure 2. The tracks 28 and 30 having the grooves 25 are in the form of annular rings having screwthreads on the inner and outer surfaces 68 and 70 respectively. The inner and outer races 12 and 14 are provided with screw threads 72 and 74 attheir ends and the rings 28 and 30 are screwed onto the threads 72 and 74. Once again tapered bearings are arranged between the grooves 25.

In the embodiments of Figures 5 and 6 the rollers and cross members are connected to the annular plate 18 in the same manner as described with reference to Figures 1 to 3.

The roller bearing according to the preferred embodiment of the present invention overcomes problems due to lateral movement of the rollers and races along the shaft on which the bearing is used in view of the thrust bearings arranged between the races and the cage and also allows fortransverse movementofthe rollersto overcome changes in distance between the races 12 and 14.

The axle in the preferred embodiment can be of any diameter provided that it can be easily received in the recess 47 and may be of any reasonable length dependent on the depth of recess 47.

In the embodiment of Figures 9 and 10 the cross members 20 are U-shaped in transverse section (see Figure 9) and define square openings 60 at the ends of the rollers 22. In this embodiment the square washer 38 is retained between the cross member 20 and is movable to locate the rollers in the same manner as described above.

The invention has the advantage that it allowsthe rollers to be relatively close to the annular plate 18 thereby reducing the size ofthe bearing whilst maintaining its load carrying capacity.

Claims

1. A roller bearing having an inner race and an outer race, a cage for locating at least one roller between the inner race and the outer race, said cage including a roller retaining meansfor locating the roller relative to the cage so thatthe roller can move in a direction transverse to the longitudinal axis of the bearing, said retaining means comprising an axle holder having an axle, said roller being mounted on the axle for rotation about the axle.

2. A roller bearing according to Claim 1 wherein said retaining means includes a recess in said cage, said axle holder being slidably received in said recess.

3. A roller bearing accordingto Claim 1 wherein said cage includes cross members and said axle holder is slidably received between adjacent cross members.

4. A roller bearing according to Claim 1, Claim 2 or Claim 3 wherein said roller has a recess in each of its ends for receiving said axle and bearing means being disposed between the axle and the roller.

5. A roller bearing according to Claim 1 wherein thrust bearings are disposed between the cage and the inner race and between the cage and the outer race.

6. A roller bearing according to (:laim 1 wherein the axle holder comprises a squarewasher.

7. A roller bearing substantially as described herein with reference to and as illustrated in Figures 1 to 4 7 and 8 of the accompanying drawings.

8. A roller bearing substantially as described herein with reference to and as illustrated in Figures 5, 7 and 8 of the accompanying drawings.

9. A roller bearing substantially as described herein with reference to and as illustrated in Figures 6, 7 and 8 of the accompanying drawings.

10. A roller bearing substantially as described herein with reference to and as illustrated in Figures 9, 10,7 and 8 ofthe accompanying drawings.