Telescopic assembly

Patent metadata

Field	Value
Publication number	US-9566996-B2
Application number	US-201414906952-A
Country	US
Kind code	B2
Filing date	Jul 24, 2014
Priority date	Jul 24, 2013
Publication date	Feb 14, 2017
Grant date	Feb 14, 2017

Abstract

A telescopic assembly comprises a first portion and a second portion and a support bearing assembly that acts between the two portions; the two portions being able to move relatively along a common path during telescopic adjustment; the support bearing assembly being located between the two portions and locating the two portions relative to one another to remove free play between the two portions that would otherwise occur in at least one direction orthogonal to the telescopic movement; characterized in that the support bearing assembly is fixed in position between the two portions by a release mechanism that is arranged, in use, to cause the support bearing assembly to grip both the first and second portions when they are not moving telescopically, to automatically release that grip upon relative telescopic movement of the two portions that exceeds a predetermined distance, and to automatically re-engage.

First claim

The invention claimed is:

1. A telescopic assembly comprising:
a first portion and a second portion and a support bearing assembly that acts between the first and second portions;
the first and second portions being able to move relatively along a common path during telescopic adjustment;
the support bearing assembly being located between the first and second portions and locating the first and second portions relative to one another to remove free play between the first and second portions that would otherwise occur in at least one direction orthogonal to the telescopic movement;
wherein the support bearing assembly is fixed in position between the first and second portions by a release mechanism that is arranged, in use, to cause the support bearing assembly to grip both the first and second portions when they are not moving telescopically, to automatically release that grip upon relative telescopic movement of the first and second portions that exceeds a predetermined distance, and to automatically re-engage that grip when the relative telescopic movement has subsequently stopped.

2. The telescopic assembly of claim 1 , wherein the first portion comprises an inner tubular portion or an outer tubular portion, and the second portion comprises the other of an inner portion and an outer portion, with an end of the inner portion fitting within an end of the outer portion, the support bearing assembly being located in the gap formed between the inner and outer portions.

3. The telescopic assembly of claim 2 , wherein the inner and outer portions comprise cylindrical tubes which are arranged around a common axis along which the telescopic movement occurs, and the support bearing assembly permits relative rotation between the first and second portions as well as permitting axial telescopic movement.

4. The telescopic assembly of claim 1 , wherein the bearing assembly includes an inner and outer annular bearing race, and a plurality of bearings located between the races.

5. The telescopic assembly of claim 4 wherein one of the bearing races is fixed in position on the first portion, and the release mechanism is arranged to releasably grip the other bearing races to the second portion.

6. The telescopic assembly of claim 4 , wherein the first portion is an outer tube, the outer bearing race is secured to the outer tube whilst the inner bearing race can releasably moved relative to the second (inner) portion.

7. The telescopic assembly of claim 6 , wherein a part of the release mechanism is located between the inner bearing race and the inner tube.

8. The telescopic assembly of claim 4 , wherein the first portion is an inner tube, the inner bearing race is fixed in position and the outer race releasably gripped by the release mechanism.

9. The telescopic assembly of claim 8 , wherein part of the release mechanism is located between the outer race and the outer tube.

10. The telescopic assembly of claim 4 , wherein the bearing race is fixed to the first portion and engages the first portion through a resilient spacer ensuring that a force is applied between the bearing race and the first portion, removing any free play.

11. The telescopic assembly of claim 10 , wherein the bearing race, or resilient spacer, is secured to the first portion so that they cannot move during normal use.

12. The telescopic assembly of claim 1 , wherein the inner tubular portion is fitted inside the inner annular race and the outer tubular portion may be fitted around the outer bearing race.

13. The telescopic assembly of claim 1 , wherein the release mechanism includes at least one gripper that contacts the second portion and at least one reaction member that acts between the bearing race and the gripper, the gripper in use securely gripping the second portion when the assembly is not moving telescopically, and automatically releasing its grip on the second portion when it is moving.

14. The telescopic assembly of claim 13 , wherein the gripper or each gripper comprises a roller.

15. The telescopic assembly of claim 14 , wherein the roller, when only subject to a low force from the wedge, can rotate freely along the second portion but when subject to a high force, as occurs when the telescopic movement has stopped, can no longer slide and so grips the second portion.

16. The telescopic assembly of claim 13 , wherein the release mechanism includes two or more reaction members, each reaction member being associated with two grippers.

17. The telescopic assembly of claim 16 , wherein each reaction member comprises a first side that engages one gripper and a second side that engages the other gripper, the two sides extending away from each other on opposing sides of the bearing race and optionally being connected by a central region, each gripper in use being wedged between a respective side and the second portion.

18. The telescopic assembly of claim 13 , wherein the release mechanism also includes a biasing means, such as a spring, that is associated with each gripper, and which in use with no telescopic movement of the assembly, biases the gripper into a position where it is forced into engagement with the reaction member and the second portion, the biasing force being reacted in part by the reaction member and in part by the second portion.

19. The telescopic assembly of claim 18 , wherein the release mechanism further comprises a slide element which is a sliding fit onto the second portion and passes between the bearing assembly and second portion, the slide element having opposed ends, one end on each side of the bearing races, each end defining a respective stopper, each of the biasing means acting between a stopper and a respective gripper.

20. A steering column assembly comprising a telescopic shroud having upper and lower portions that surround and support a telescopic steering shaft having upper and lower portions, one of the upper and lower portions of the shroud forming the first or second portion of a telescopic assembly of claim 1 and one of the upper and lower portions of the steering shaft forming the other of the first and second portions of claim 1 .

Assignees

• Trw Ltd

Inventors

• Wilkes Mark Anthony

Classifications

• F16D3/065

  by means of rolling elements · CPC title

• B62D1/192 Primary

  Yieldable or collapsible columns · CPC title

• B62D1/185 Primary

  adjustable by axial displacement, e.g. telescopically (B62D1/183, B62D1/187, B62D1/19 take precedence) · CPC title

• F16C3/035

  with built-in bearings · CPC title

• F16C2326/24

  Steering systems, e.g. steering rods or columns · CPC title