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 and the bearing liner has at least one of: (a) a flexural modulus of from 20 to 35 GPa and (b) a flexural strength of from 500 to 700 MPa.

Claims

1. A bearing comprising: an inner ring, an outer ring, and a bearing liner disposed therebetween, the bearing liner comprising: a first fabric impregnated with a resin, and a second fabric, wherein the first fabric and the second fabric are compressed together causing at least some of the resin in the first fabric to transfer to the second fabric, wherein the bearing liner has at least one of: (a) a flexural modulus of from 20 to 35 GPa, and (b) a flexural strength of from 500 to 700 MPa.

2. The bearing of claim 1, wherein the bearing liner has at least one of: (a) a flexural modulus of from 25 to 30 GPa, and (b) a flexural strength of from 550 to 650 MPa.

3. The bearing of claim 1, wherein the resin comprises an epoxy resin.

4. The bearing of claim 1, wherein the liner comprises a fabric; and the resin is impregnated into the fabric.

5. The bearing of claim 4, wherein the fabric comprises: a bearing element contact surface comprising lubricating fibers, and structural fibers supporting the bearing element contact surface.

6. The bearing of claim 5, wherein the lubricating fibers comprise PTFE.

7. The bearing of claim 5, wherein the structural fibers comprise at least one of: glass, carbon fiber, aramid, polyether ether ketone, polyester, polyamide, and polyphenylene sulphide.

8. The bearing of claim 1, wherein the bearing is a self-lubricating bearing.

9. The bearing of claim 1, wherein the bearing is a rotary aircraft bearing.

10. The bearing of claim 9, wherein the rotary aircraft bearing is installed into an aircraft.

11. The bearing of claim 1, wherein the bearing is designed for operate effectively within an environment having a temperature range of 55 C. to +163 C.

12. A bearing comprising: a ring; and a bearing liner disposed on the inner surface of the ring, the bearing liner comprising: a first fabric impregnated with a resin, and a second fabric, wherein the first fabric and the second fabric are compressed together causing at least some of the resin in the first fabric to transfer to the second fabric, wherein the bearing liner has at least one of: (a) a flexural modulus of from 20 to 35 GPa, and (b) a flexural strength of from 500 to 700 MPa.

13. The bearing of claim 12, wherein the bearing is designed for operate effectively within an environment having a temperature range of 55 C. to +163 C.

14. A method of manufacturing a bearing, the method comprising steps of: providing a first fabric impregnated with a resin; providing a second fabric; contacting and compressing together the first and second fabrics, whereby at least some of the resin in the first fabric transfers to the second fabric to form a bearing liner; and assembling the bearing liner between an inner ring and an outer ring, wherein the resulting bearing liner having at least one of: (a) a flexural modulus of from 20 to 35 GPa, and (b) a flexural strength of from 500 to 700 MPa.

15. The method of claim 14, further comprising a step of attaching the bearing liner to a bearing component.

16. The method of claim 14, further comprising a step of attaching the bearing liner to the inner ring.

17. The method of claim 14, further comprising a step of attaching the bearing liner to the outer ring.

18. The bearing of claim 14, wherein the bearing is designed for operate effectively within an environment having a temperature range of 55 C. to +163 C.

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. (*Approx.) Structural Warp Yarn lubricating Structural Lubricating Ma- Warp Yarn Weft Yarn Weft Yarn terial (mm) Material (mm) Material (mm) Material (mm) Glass 0.13* PTFE 0.13* Glass 0.12* PTFE 0.13*

(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.