AU679891B3

AU679891B3 - Resilient tolerance ring and shaft arrangement including this ring

Info

Publication number: AU679891B3
Application number: AU46691/96A
Authority: AU
Inventors: Colin Andrew Mitchell
Original assignee: Torrington Co Ltd; Torrington Co
Current assignee: Torrington Co Ltd
Priority date: 1995-02-14
Filing date: 1996-02-13
Publication date: 1997-07-10
Anticipated expiration: 2002-02-13
Also published as: WO1996025607A1; ES1038009Y; BR9605307A; GB9502846D0; DE29680093U1; GB2298005B; GB2298005A; ES1038009U; AU4669196A; JP3038627U; CN2322352Y

Description

Resilient tolerance ring and shaft arrangement Including this ring

This invention relates to a resilient tolerance ring and a shaft arrangement including the ring.

FR-A-538,058 discloses a ball bearing with a split conical sheath mounted fast on a shaft by a nut; however the splits in the sheath serve a different purpose from that which forms the object of the present invention.

GB-B 2 231 099 discloses a tolerance ring of resilient material incorporated in a shaft arrangement, the ring having an inner shoulder which locates in a groove in the shaft, whilst an outer end surface of the ring is chamfered and acts against a surface of an inner race ring which in turn traps the inner shoulder of the ring in the groove under pressure of a compression spring. By extending the groove in the shaft longer than the axial length of the shoulder of the ring, it is possible for the ring to move relative to the shaft as may be when a steering wheel is tightened onto the shaft against the ring.

Figure 1 illustrates the type of ring used at present and it will be noted that, in order to fit the ring onto the shaft, the ring is split along its axial length at 1 so that it will be split open to enable the internal shoulder to ride along the outer surface of the shaft until it reaches the groove in the shaft, where it snap fits.

However, it has been noted that under certain conditions of axial load, distortion can occur, giving problems with controlling the ring. According to one aspect of the present invention, there is provided a tolerance ring of resilient material, for use in a shaft arrangement including a shaft having a groove and at least one rolling bearing member mounted about the shaft, the ring being arranged to fit around the shaft and having one end to contact the rolling bearing member and the ring being provided with a portion at said one end arranged to extend into said groove and a chamfered surface on the outside of the ring at said one end, characterised in that at least one slit extends from said one end towards but not as far as the other end of the ring.

According to another aspect of the present invention, there is provided a shaft arrangement including a shaft having a groove, at least one rolling bearing member mounted about the shaft, a tolerance ring of resilient material fitting around the shaft and having one end in contact with the rolling bearing member, said ring having at said one end a portion extending into said groove, a chamfered surface on the outside of the ring at said one end and at least one slit and compression spring means acting to urge the roller bearing member against the ring so that the force of the spring means acts on the ring to assist in retaining the ring in the groove, characterised in that said at least one slit extends from said one end towards but not as far as the other end of the ring.

Preferably, there are three of said slits, each extending from said one end towards but not as far as the other end of the ring.

For a better understanding of the invention and to show how the same may be carried into effect, reference will now be made, by way of example, to Figures 2, 3 and 4 of the accompanying drawing, in which:- Figure 2 is a partial longitudinal cross-section of part of one end of a shaft arrangement incorporating a tolerance ring,

Figure 3 is a diagrammatic perspective view of the tolerance ring illustrated in Figure 2, and

Figure 4 is a longitudinal cross-sectional view of the tolerance ring.

Figure 2 shows part of a shaft 2 which has an angular contact roller bearing race 3 mounted thereon and an outer tube 4 mounted on the race 3.

At the end of the tube 4 shown, a resilient tolerance ring 5 is provided with an inner shoulder 6 which locates in a groove 7 which is rolled, pressed or machined in the shaft 2. The outer surface of the ring 5 at the end with the shoulder 6 is provided with a chamfered surface 8, which acts against a surface 9 of an inner race ring 10 to trap the inner shoulder 6 in the groove 7 under pressure of a compression spring (not shown) acting in the direction of the arrow in Figure 2. This prevents the inner shoulder 6 riding over the groove edge.

By extending the groove 7 longer than the axial length of the shoulder 6, it is possible for the ring 5 to move relative to the shaft as may be when a steering wheel is tightened onto the shaft against the opposite end surface 11 of the ring 5.

As illustrated in Figures 3 and 4, the ring 5 is provided with at least one, and in the version shown, three, substantially equi-spaced slits 12 which extend from the end of the ring 5 having the inner shoulder 6 towards, but not as far as, the other end 11 of the ring. By stopping each slit 12 short of the end 11, the axial strength of the ring 5 is strengthened as compared with the Figure 1 version of the ring and the more tube-like structure is less susceptible to distortion for the same applied load.

To fit the ring 5, the ring is fitted onto the shaft 2 (the main internal diameter of the ring 5 being a clearance fit on the shaft 2) , the tube 4 is forced against its spring against the direction of the arrow in Figure 2 and the inner shoulder 6 of the ring 5 is snap fitted into the groove 7 which is clear. The tube 4 is then released to enable the spring pressure to force the shoulder 6 into the groove 7.

Claims

CLAIMS :

1. A tolerance ring (5) of resilient material, for use in a shaft arrangement including a shaft (2) having a groove (7) and at least one rolling bearing member (10) mounted about the shaft, the ring (5) being arranged to fit around the shaft and having one end (8) to contact the rolling bearing member (10) and the ring being provided with a portion (6) at said one end arranged to extend into said groove (7) and a chamfered surface (8) on the outside of the ring at said one end, characterised in that at least one slit (12) extends from said one end (8) towards but not as far as the other end of the ring (5) .

2. A tolerance ring, wherein the resilient material is a plastics material.

3. A tolerance ring according to claim 1 or 2, wherein there are three of said slits (12) each extending from said one end towards but not as far as the other end of the ring (5) , each slit being substantially equi-spaced around the ring.

4. A shaft arrangement including a shaft (2) having a groove (7) , at least one rolling bearing member (10) mounted about the shaft (2) , a tolerance ring (5) of resilient material fitting around the shaft and having one end (8) in contact with the rolling bearing member, said ring (5) having at said one end a portion (6) extending into said groove, a chamfered surface (8) on the outside of the ring at said one end and at least one slit (12) and compression spring means acting to urge the roller bearing member (10) against the ring (5) so that the force of the spring means acts on the ring (5) to assist in retaining the ring in the groove (7) , characterised in that said at least one slit (12) extends from said one end (8) towards but not as far as the other end of the ring.

5. A shaft arrangement according to claim 4, wherein the resilient material is a plastics material.

6. A shaft arrangement according to claim 4 or 5, wherein there are three of said slits (12) each extending from said one end (8) towards but not as far as the other end of the ring (5) , each slit being substantially equi-spaced around the ring.