Plain bearing

Abstract

A bearing comprising: (a) an inner ring, (b) an outer ring, and (c) a bearing liner disposed therebetween, wherein the bearing liner comprises a resin having a glass transition temperature of less than 150 C.

Claims

1. A bearing comprising: an inner ring, an outer ring, and a first fabric impregnated with a resin having a glass transition temperature of less than 150 C., a second fabric, a bearing liner formed by contacting and compressing together the first fabric and the second fabric, whereby at least some of the resin in the first fabric transfers to the second fabric, the bearing layer being disposed between the inner ring and the outer ring.

2. The bearing of claim 1, wherein the resin has a glass transition temperature of from 100 C. to 140 C.

3. The bearing of claim 1, wherein the resin has a glass transition temperature of from 120 C. to 130 C.

4. The bearing of claim 1, wherein the resin is an epoxy resin.

5. The bearing of claim 1, wherein the first fabric is a woven fabric.

6. The bearing of claim 5, wherein the woven fabric comprises: a bearing element contact surface comprising lubricating fibers, and structural fibers supporting the bearing element contact surface.

7. The bearing of claim 6, wherein the lubricating fibers comprise PTFE or graphite.

8. The bearing of claim 6, wherein the structural fibers comprise at least one of: glass, carbon fiber, aramid, polyether ether ketone, polyester, polyamide, and polyphenylene sulphide.

9. A bearing comprising: a ring, a first fabric impregnated with a resin having a glass transition temperature of less than 150 C., a second fabric, and a bearing liner formed by contacting and compressing together the first fabric and the second fabric, whereby at least some of the resin in the first fabric transfers to the second fabric, the bearing layer being disposed on at least one of an inner surface and an outer surface of the ring.

10. The bearing of claim 9, wherein the bearing is a self-lubricating bearing.

11. The bearing of claim 9, wherein the bearing is a rotary aircraft bearing.

12. The bearing of claim 11, wherein the rotary aircraft bearing is integrated into a rotary aircraft.

13. A method of manufacturing a bearing liner for use in a bearing, the method comprising: providing a first fabric impregnated with a resin having a glass transition temperature of less than 150 C., providing a second fabric, and contacting and compressing together the first fabric and the second fabric, whereby at least some of the resin in the first fabric transfers to the second fabric, integrating the bearing liner into a bearing, wherein the bearing comprises: an inner ring, and an outer ring, wherein the bearing liner is disposed between the inner ring and the outer ring.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The invention will now be described with reference to the following non-limiting Figures, in which:

(2) FIG. 1 shows a part-cutaway view of a bearing according to the present invention;

(3) FIG. 2 shows a plot of the results of a coupon test of a prior art bearing liner and a bearing liner according to the present invention; and

(4) FIG. 3 shows a plot of the results of a unidirectional bearing test of a prior art bearing and a bearing according to the present invention.

DETAILED DESCRIPTION OF THE PRESENT INVENTION

(5) Referring to FIG. 1, the bearing (shown generally at 1) comprises an inner ring 2, an outer ring 3 and a bearing liner 4 disposed therebetween.

(6) The invention will now be described in relation to the following non-limiting examples.

Example 1

(7) A bearing liner was manufactured as follows. A woven fabric was prepared having the characteristics set out in Table 1.

(8) TABLE-US-00001 TABLE 1 Characteristics of woven fabric of Comparative Example 1. Structural lubricating Structural Lubricating Warp Yarn Warp Yarn Weft Yarn Weft Yarn Mate- (mm) Mate- (mm) Mate- (mm) Mate- (mm) rial rial rial rial Glass 0.13* PTFE 0.13* Glass 0.12* PTFE 0.13* (*Approx.)

(9) The woven fabric was laminated with a glass fiber sheet pre-impregnated with M77 epoxy resin. The resulting laminate was compressed at an elevated temperature so that the M77 epoxy resin bled through to impregnate the woven fabric.

Comparative Example 1

(10) A bearing liner was prepared in the same manner as Example 1 but with the M77 epoxy resin replaced by a phenolic resin.

(11) The bearing liners of Example 1 and Comparative Example 1 were subjected to a coupon test (flat sample test based on 15 mm^2 liner sliding on a reciprocating bartest conditions: 80 MPa, 10.5 mm, 2 Hz), and the results are shown in FIG. 2 (Comparative Example 1 was tested twice). It can be seen that the working lifetime of the bearing liner of Example 1 was greater than the working lifetime of the bearing liner Comparative Example 1.

Example 2

(12) A bearing liner was prepared in the same manner as Example 1. It was then placed between an inner ring and an outer ring to form a bearing.

Comparative Example 2

(13) A bearing liner was prepared in the same manner as Comparative Example 1. It was then placed between an inner ring and an outer ring to form a bearing.

(14) The bearings of Example 2 and Comparative Example 2 were subjected to a unidirectional bearing test (5 rotation, projected pressure 50 MPa, oscillating at 25 Hz), and the results are shown in FIG. 3 (Comparative Example 2 was tested four times, Example 2 was tested twice). It can be seen that the working lifetime of the bearing of Example 2 was greater than the working lifetime of the bearing of Comparative Example 2.

(15) The foregoing detailed description has been provided by way of explanation and illustration, and is not intended to limit the scope of the appended claims. Many variations in the presently preferred embodiments illustrated herein will be apparent to one of ordinary skill in the art, and remain within the scope of the appended claims and their equivalents.