GB2218750A

GB2218750A - Rolling bearing cage

Info

Publication number: GB2218750A
Application number: GB8908290A
Authority: GB
Inventors: Bruno Schemmel; Armin Olschewski; Heinrich Kunkel; Herbert Dobhan
Original assignee: SKF GmbH
Current assignee: SKF GmbH
Priority date: 1988-04-14
Filing date: 1989-04-12
Publication date: 1989-11-22
Anticipated expiration: 2009-04-12
Also published as: GB8908290D0; DE3812345C2; GB2218750B; FR2630171B1; DE3812345A1; FR2630171A1

Description

UP 7 5 0 1 ROLLING BEARING CAGE 0 The present invention relates to a cage

for a rolling bearing comprising two or more components, in which retaining projections are provided on one cage component, the free ends of these retaining projections having radially directed portions with undercut surfaces which abut against corresponding abutment surfaces of the other cage component after the retaining projections have been passed through recesses in the said other cage component.

Cages of this type are known, for example, from GB-A-2078874. In these known cages it is necessary to provide special securing members to prevent the retaining projections from being unintentionally disengaged.

The invention is based on the object of devising a rolling bearing cage of the above-mentioned type comprising two or more components, which comprises a small number of components, which can be easily assembled and in which the cage components are held together securely, even when they get hot and when subjected to axially acting forces.

According to the invention, this object is achieved in that the total radial height of the retaining projections between the outer surfaces of the radial portions and the supporting surfaces remote therefrom is greater than the radial height of the recesses, and in that the supporting surfaces of one cage component, after assembly of the cage components, are arranged supported under elastic deformation of the retaining projections and of the adjacent cage portions on associated surfaces of the recesses of the other cage component.

As a result of this development there is provided a rolling bearing cage comprising two or more components, for example of plastics material, the parts of which can be produced economically by casting or injection moulding with the moulds having axially removable sliders.

is In another aspect, the invention provides a rolling bearing cage comprising a plurality of components joined together, one at-least-partannular component being arranged on a common axis with another at-leastpart-annular component and together defining at least one pocket for a rolling element, one said component having an elastically bendable projection extending axially into an opening in the other said component, the shank of the projection engaging the radially inner and outer surfaces of the opening, the free end of the projection and the other said component having opposed radially extending surfaces which abut each other and resist separation of the components, wherein the free end of the projection is radially offset from the shank and the projection is radially elastically stressed in the direction of offset of the free end.

In the accompanying drawings; Figure 1 is a longitudinal section through a ball bearing with a two- component cage in which the components are held together by a snap-fit connection; Figure 2 is part of a side view of the bearing shown in Figure 1, viewed from the left; 1 A 1 1 Figure 3 is part of a plan view of the cage; Figure 4 is an enlarged view in section of part of the cage showing the connection between the two components; and Figure 5 is part of another exemplified embodiment of a cage.

A cage 10 for a deep groove radial ball bearing with race rings 11 and 12 and balls 13 as illustrated in Figs. 1 to 4, comprises an annular comb component 14 provided with rolling body pockets 15 and an annular cover washer component 16 which closes the rolling body pockets 15 the two components 14 and 16 being arranged on a common axis. Retaining projections 17 with inner surfaces 18 are provided at the end of bars 19 extending from comb component 14; these retaining projections 17 extend into openings or recesses 20 of the cover washer 16 and they engage behind the cover washer 16 with a radially outwardly directed offset portion 21. On the side nearest the inner race 12, the retaining projections 17 are provided with shoulders 22 which lead to the shank of the projections and which, during assembly of the cage 10, bear with supporting surfaces 23 against radially inner surfaces 24 of the recesses 20 in the cover washer 16.

The total radial height A of each retaining projection 17 between the outer surface 25 of the radial portion 21 and the supporting surface 23 is greater than the radial height B of each recess 20. Advantageously, the radial height C between the outer surface 25 of the radial portion 21 and the inner surface 18 of each retaining projection 17 in the front region is the same as or smaller than the radial height B of the recesses 2.0, so as not to impede assembly of the cage components 14 and 16. When the retaining projections 17 are pushed into the recesses 20, firstly inclined surfaces 26 of the radially outward directed portions 21 are applied against edges 27 at the transition between the end face 28 of the cover washer 16 and the radially outer surfaces 29 of the recesses 20. Accordingly, upon further pushing-in of the retaining projections 17, the latter are bent radially inwards elastically and the surface 30 of the shoulder 22 abuts against inclined surfaces 31 of the cover washer 16, which surfaces form the transition between the end face 28 nearer the comb part 14 and the radially inner surfaces 24 of the recesses 20. The continued assembly of the cage parts 14 and 16 is effected under axial pressure and elastic deformation of the retaining projections 17 and of the cover washer 16 in the vicinity of the recesses 20.

Preferably the radially inner surfaces 24 (Fig. 2) of the recesses (20) are of convex shape so that the radially inner walls 33 of the recesses 20 having the surfaces 24 are weakened in the vicinity of corners 34 and can yield elastically. As soon as the retaining projections 17 project axially from the cover washer 16 with the radially outwardly directed offset portions 21, they spring radially outwards so that the undercut surfaces 35 of the radially outwardly directed portions 21 abut against the end face 36 of the cover washer 16. The retaining projections 17 are reliably prevented from being disengaged by the supporting surfaces 23 bearing against the radially inner surfaces 24 of the recesses 20 in the cover washer 16, since to separate the cage components 14 and 16, the retaining projections 17 firstly have to be pressed radially inwards causing elastic deformation of the walls 33.

is The width D of the retaining projections 17 is smaller than the width E of the recesses 20, so that there is no peripheral constraint between the retaining projections 17 and the cover washer 16. Precise location of the cover washer 16 relative to the comb part 14 in the peripheral direction is effected by axially directed projections 37 on the cover washer 16, which projections engage in recesses 38 of the comb part 14. In this case the lateral surfaces 39 of the projections 37 are wedge-shaped so that accurate positioning of the cover washer 16 relative to the comb part 14 is necessarily ensured in peripheral direction (Fig. 3).

The embodiment illustrated by way of example in Fig. 5 differs from the construction just described merely in that the retaining projections 17 have an inclined portion 40 in their front region and the inclined portions 31 of the recesses 20 (Fig. 4) are omitted.

A cage according to the invention can be applied not only to ball bearings but also, for example, to cylindrical roller bearings, etc.

Claims

CLAIMS is A cage (10) for a rolling bearing comprising two or more

components (14, 16) in which retaining projections (17) are provided on one cage component (14), the free ends of these retaining projections (17) having radially directed portions (21) with undercut surfaces (35) which abut against corresponding abutment surfaces (36) of the other cage component (16) after the retaining projections (17) have been passed through recesses (20) in the said other cage component (16), characterised in that the total radial height (A) of the retaining projections (17) between the outer surfaces (25) of the radial portions, (21) and the supporting surfaces (23) is greater than the radial height (B) of the recesses (20), and in that the supporting surfaces (23) of one cage component (14), after assembly of the cage components (14,16), are arranged supported under elastic deformation of the retaining projections (17) and of the adjacent cage portions (33) on associated surfaces (24) of the recesses (20) of the other cage component (16).
2. A rolling bearing cage according to Claim 1, characterised in that at the transition between the end face (28) and the surfaces (24) of the recesses (20) the cage component (16) has an inclined portion (31).
3. A rolling bearing cage comprising a plurality of components joined together, one at-least-part-annular component being arranged on a common axis with another at-least-part-annular component and together defining at least one pocket for a rolling element, 1\ k A one said component having an elastically bendable projection extending axially S into an opening in the other said component, the shank of the projection engaging the radially inner and outer surfaces of the opening, the free end of the projection and the other said component having opposed radially extending surfaces which abut each other and resist separation of the components, wherein the free end of the projection is radially offset from the shank and the projection is radially elastically stressed in the direction of offset of the free end.
4. A cage for a rolling bearing substantially as herein described with reference to and as shown in the accompanying drawings.

Amendments to the claims have been filed as follows 1. A cage (10) for a rolling bearing comprising two or more components (14, 16) in which retaining projections (17) are provided on one cage component (14), the free ends of these retaining projections (17) having radially directed portions (21) with undercut surfaces (35) which abut against corresponding abutment surfaces (36) of the other cage component (16) after the retaining projections (17) have been passed through recesses (20) in the said other cage component (16), characterised in that the total radial height (A) of the retaining projections (17) between the outer surfaces (25) of the radial portions, (21) and the supporting surfaces (23) is greater than the radial height (B) of the recesses (20), and in that the supporting surfaces (23) of one cage component (14), after assembly of the cage components (14,16), are arranged supported under elastic deformation of the retaining projections (17) and of the adjacent cage portions (33) on associated surfaces (24) of the recesses (20) of the other cage component (16).

2. A rolling bearing cage according to Claim 1, characterised in that at the transition between the end face (28) and the surfaces (24) of the recesses (20) the cage component (16) has an inclined portion (31).

3. A rolling bearing cage according to Claim 1 or 2, characterised in that the height (C) between the outer surfaces (25) of the radial portions (21) and the inner surfaces (18) of the retaining projections (17) in the front region is the same as or smaller than the radial height (B) of the recesses (20).

J - q - 13 4. A rolling bearing cage according to Claim 1, characterised in that the retaining projections (17) respectively have an inclined portion (40) in their front region.
5. A rolling bearing cage according to any one of Claims 1 to 4 characterised in that the radially outward directed portions (21) of the retaining projections (17) have inclined surfaces (26).
6. A rolling bearing cage according to any one of Claims 1 to 5, characterised in that the walls (33) of the recesses (20) having the associated surfaces (24) are provided with weak points in the vicinity of the corners (34).
7. A rolling bearing cage according to Claim 6, characterised in that the surfaces (24) are of convex shape.
8. A rolling bearing cage according to any one of Claims 1 to 7, characterised in that the width (D) of the retaining projections (17) is smaller than the width (E) of the recesses (20).
9. A rolling bearing cage according to any one of Claims 1 to 8, characterised in that on one cage component (16) there are provided projections (37) which are directed axially to the other cage component (14) and which engage in corresponding recesses (38) of the other cage component (14).
10. A rolling bearing cage according to Claim 9, characterised in that the lateral surfaces (39) of the projections (37) are wedge-shaped.

^ 10 -
11. A rolling bearing cage comprising a plurality of components joined together, one at-least-part-annular component being arranged on a common axis with another at-least-part-annular component and together defining at least one pocket for a rolling element, one said component having an elastically bendable projection extending axially into an opening in the other said component, the shank of the projection engaging the radially inner and outer surfaces of the opening, the free end of the projection and the other said component having opposed radially extending surfaces which abut each other and resist separation of the components, wherein the free end of the projection is radially offset from the shank and the projection is radially elastically stressed in the direction of offset of the free end.
12. A cage for a rolling bearing substantially as herein described with reference to and as shown in the accompanying drawings.

Published 1989 at The Patent Office, State House, 66171 High Holborn. London WClR 4TP Further copies maybe obtained from The Patent Office. Sales Branch, St Mary Cray, Orpington, Kent BPS 3RD. Printed by Multiplex techniques Itd, St Mary Cray, Kent, Con. 1187 1