GB2278650A

GB2278650A - Rolling bearing for high temperature applications

Info

Publication number: GB2278650A
Application number: GB9408915A
Authority: GB
Inventors: Heinrich Winter
Original assignee: SKF GmbH
Current assignee: SKF GmbH
Priority date: 1993-06-01
Filing date: 1994-05-05
Publication date: 1994-12-07
Anticipated expiration: 2014-05-05
Also published as: DE9308212U1; FR2706003B1; GB2278650B; GB9408915D0; FR2706003A1

Abstract

A rolling bearing for high temperature applications comprises races (1, 2) made from ceramic material, each consisting of a number of track segments. Each race is surrounded by an assembly ring (10) of temperature-resistant steel, having flanges (11) which are in axial engagement with the halls (3) or rollers (13) of the bearing. Each assembly ring (10) is axially split. Each race (1, 2) has slightly conical faces (8) which engage the flanges (11) to produce a wedging action as the halves of the assembly ring (10) are moved axially into position during assembly, to hold the track segments in position. <IMAGE>

Description

Rolling bearing for high temperature applications The invention relates to roller bearings for high temperature applications.

More particularly, the invention relates to rolling bearings of the kind having races made from ceramic material and flanges of temperature-resistant steel.

From US patent 3178241, it is already known to insert a one-piece race for a roller bearing into a steel bush and to fit on flanged rings of steel. This produces a compact roller bearing which is outwardly protected against damage to the ceramic rings and which has improved bearing capacity. One-piece races of ceramic material are however extremely expensive, particularly in the case of the larger roller bearings and also entail a considerable risk of breakage when they are reasonably dimensioned.

The object of the invention is to provide a rolling bearing of the type referred to, which, for acceptable annular wall thicknesses, offers a high degree of stability and loading capacity combined with a low manufacturing cost.

This invention consists in a roller bearing of the kind set forth, in which the races consist of track portions and are surrounded by an assembly ring of temperatureresistant steel which is provided with flange portions against which the rolling bodies can run axially.

This segmental construction reduces to acceptable Icvels the one-picce volume which necds to be machined, particularly where larger rolling bearings are involved.

According to the diameter of the rolling bearing, so three or more track segments are fitted together and are form-lockingly inserted into an assembly ring. Also, in the case of a ball-bearing type of bearing, the segments are designed for purely radial loading so that they have no edges, grooves etc. of any kind or perhaps only minor indications of such configurations. The axial loading is supported solely by the edge of flange portions which are part of the assembly ring which is manufactured from temperature-resistant steel.

The rolling bearing according to the invention and which is so constructed is considerably more competitively costed which constitutes a significant step forward when the bearings are intended to be used under extreme conditions, entailing relatively minimal effective life. The assembly ring can take various forms.

The invention will now be described, by way of example, with reference to the accompanying drawings, in which: Fig. 1 is a partial longitudinal section through a ball-bearing with track segments and assembly rings in accordance with the invention; Fig. 2 is a section on line A-A in Fig. 1; and Fig. 3 is a partial longitudinal section through a roller bearing with track segments in accordance with the invention.

The ball-bearing for high temperature conditions which is shown in Figs. 1 and 2 consists of an outer ring 1 and an inner ring 2, with balls 3 of ceramic material disposed between them.

As can be more clearly seen in Fig. 2, both races 1, 2 contain track segments 4 which are joined to one another, by any known means, at the joints 5.

The track segments 4 are made from ceramic material and have a substantially rectangular cross-section. Only one groove 6 of minimal depth is provided. From the edges 7 of the groove 6, shoulder surfaces 8 of slightly conically inclined form extend to the lateral surfaces 9. They serve as a means of clamping in respectively two laterally pressed-on assembly ring halves 10 and are made from temperatureresistant steel.

The assembly ring halves 10 of the outer ring 1 have a U-shaped profile and form a flange portion 11. The end face of this flange portion 11 is adapted to the ball 3 and accommodates the axial loading of the preferably radially loaded ball-bearing.

The assembly ring halves 10 of the inner ring 2 have an L-shaped profile, whereby only one axially extending arm is omitted, when compared with the assembly ring 10 for the outer ring 1. The angle of inclination of the shoulder surface 8 is so dimensioned that after the assembly ring halves 10 have been pressed into place, a self-retaining clamping effect is achieved. Furthermore, the length of the track segments 4 is so chosen that the clamping creates pressure in a peripheral direction and thus, at the joints 5, a merging together under pre-tension.

The roller bearing shown in Fig. 3 corresponds to the foregoing description with regard to its assembly rings 10. Only the track of the track segments 4 is made cylindrical to accommodate rollers 13.

Claims

1. A rolling bearing for high temperature applications, with races made from ceramic material and flanges of temperature-resistant steel, characterised in that the races (1, 2) consist of track segments (4) and are surrounded by an assembly ring (10) of temperature-resistant steel and provided with flange portions (11) against which the rolling bearings (3, 13) can run axially.

2. A bearing according to Claim 1, in which the assembly ring (10) is divided in the peripheral direction

3. A bearing according to Claim 1 or Claim 2, in which the flange portions (11) fix the track segments (4) radially and in form-locking manner via a clamping surface (8).

4. A bearing according to Claim 3, in which the clamping surface (8) is slightly conically formed to produce radial fixing pressure on axial assembly of the bearing.

5. A rolling bearing substantially as described with reference to, and as shown in, Figs. I and 2 or Fig. 3 of the accompanying drawings.