GB2328661A

GB2328661A - Steering column lock

Info

Publication number: GB2328661A
Application number: GB9718335A
Authority: GB
Inventors: Jorn Bechert
Original assignee: Delphi Automotive Systems France
Current assignee: Delphi Automotive Systems France
Priority date: 1997-09-01
Filing date: 1997-09-01
Publication date: 1999-03-03
Anticipated expiration: 2017-09-01
Also published as: GB2328661B; GB9718335D0

Abstract

A steering column lock for the steering column of a motor vehicle comprising a lock sleeve (20) which is securable to a rotatable portion (10) of the steering column; a tubular jacket (34) surrounding the lock sleeve; a tubular housing (32) surrounding the jacket; the lock sleeve, jacket and housing being coaxial on a common longitudinal axis (A); the jacket and housing being normally fixed relative to one another and normally rotatable relative to the lock sleeve about the longitudinal axis; the housing having a radially extending bore (54) with a lock bolt (56) slidable therein; the jacket having a radially extending aperture (36) into which the lock bolt normally extends to lock the housing relative to the jacket; and the lock sleeve having a radially extending aperture (22) into which the lock bolt can extend to lock the jacket and the housing relative to the lock sleeve; wherein the lock bolt can be moved radially away from the longitudinal axis to allow the housing to slide in the axial direction relative to the jacket. Provides a lock which is easier to assemble.

Description

STEERING COLUMN LOCK Technical Field The present invention relates to a lock for the steering column of a motor vehicle.

Background of the Invention Steering column locks for motor vehicles are well known. The aim of such locks is to inhibit steering of the motor vehicle during unauthorised use of the vehicle. Current designs of steering column locks have disadvantages in terms of difficulties in installation, assembly, and servicing.

Summarv of the Invention It is an object of the present invention to provide a steering column lock which overcomes one or more of the above mentioned disadvantages.

A steering column lock in accordance with the present invention comprises a lock sleeve which is securable to a rotatable portion of the steering column; a tubular jacket surrounding the lock sleeve; a tubular housing surrounding the jacket; the lock sleeve, jacket and housing being coaxial on a common longitudinal axis; the jacket and housing being normally fixed relative to one another and normally rotatable relative to the lock sleeve about the longitudinal axis; the housing having a radially extending bore with a lock bolt slidable therein; the jacket having a radially extending aperture into which the lock bolt normally extends to lock the housing relative to the jacket; and the lock sleeve having a radially extending aperture into which the lock bolt can extend to lock the jacket and the housing relative to the lock sleeve; wherein the lock bolt can be moved radially away from the longitudinal axis to allow the housing to slide in the axial direction relative to the jacket.

The present invention provides a steering column lock which is easy to assemble.

Brief Description of the Drawmps The present invention will now be described, by way of example, with reference to the accompanying drawings, in which: Figure 1 is a cross-sectional view of a steering column lock in accordance with the present invention, with the steering column lock in its normal (assembled and unlocked) position; Figure 2 is a cross-sectional view on the line II-II of Figure 1; Figure 3 is a cross-sectional view on the line III-III of Figure 2; Figure 4 is a side view of one of the internal grooves in the housing of the steering column lock of Figure 1; and Figures 5 to 7 are cross-sectional views of the assembly steps for and operation of the steering column lock of Figure 1.

Description of the Preferred Embodlment Referring to Figures 1 to 4 of the drawings, a tubular portion 10 of a steering column of a motor vehicle is shown, the tubular portion being rotatable about its longitudinal axis A. An inner race 12 of a bearing 14 is secured to the tubular portion 10, the bearing also having an outer race 16. A tolerance ring 18 is also secured to the tubular portion 10 at an axial separation from the bearing 14.

The steering column lock 30 in accordance with the present invention comprises a lock sleeve 20 which is secured on the tolerance ring 18 on the tubular portion 10 of the steering column; a tubular housing 32, which is preferably moulded from plastics material; and a tubular jacket 34, which is preferably extruded and machined from metallic material. The lock sleeve 20 has a number circumferentially spaced, radially extending, apertures 22 therein. The jacket 34 is positioned around the tubular portion 10 of the steering column and has a radially extending aperture 36 adjacent the apertures 22 in the lock sleeve 20. A number of inwardly directed tabs 38 are formed in one end 40 of the jacket 34, and a shoulder 42 is formed in the inner surface of the jacket a predetermined distance from said one end 40.

The outer race 16 of the bearing 14 is secured between the inwardly directed tabs 38 and the shoulder 42 of the jacket 34.

Said one end 40 of the jacket 34 also has a number of outwardly directed tabs 44 which make a sliding fit in corresponding grooves 46 in the inner surface of the housing 32. As shown in more detail in Figures 3 and 4, the grooves 46 extend from one end 48 of the housing 32 to an internal shoulder 50, and have a reducing width from said one end to the shoulder 50 with the sides 52 of the groove being at an angle a to the longitudinal direction. When assembled, the tabs 44 engage the shoulder 50 in the corresponding groove 46.

In the presently described embodiment, there are a total of five tabs, three inwardly directed tabs 38 and two outwardly directed tabs 44. The tabs 38,44 are equidistantly spaced apart (Figure 2). The asymmetrical arrangement of the outwardly directed tabs 44 and the corresponding grooves 46 and shoulders 50 ensure that the housing 32 and the jacket 34 achieve the required relative axial and rotational positions when fully assembled together.

The housing 32 has a radially extending bore 54 within which a lock bolt 56 can slide, the lock bolt being biased to normally project out of the bore. When the housing 32 and the jacket 34 are fully assembled together, the bore 54 aligns with the aperture 36 in the jacket, and the lock bolt 56 projects into the aperture 36. The housing 32 is securable to a body portion (not shown) of the motor vehicle by any suitable means. The housing 32 also houses the operating mechanism (not shown) for the lock bolt 56. The operating mechanism may be any suitable mechanism and will not be described in detail.

The steering column lock 30 is assembled by positioning the jacket 34 around the tubular part 10 of the steering column. The housing 32 is then slid onto the jacket 34 in the axial direction X (Figure 5), with the outwardly directed tabs 44 projecting into the corresponding grooves 46 in the housing. The leading edge 58 of the lock bolt 56 is chamfered, as is the edge 60 of said one end 40 of the jacket 34. As the housing 32 is slid in the direction X, the edges 58,60 engage one another and the lock bolt 56 is pushed radially outwards (relative to axis A) against the normal bias to allow further movement of the housing in the direction X. When the lock bolt 56 reaches the aperture 36 in the jacket 34, the lock bolt moves in a radially inwards direction due to the bias thereon into the aperture, as shown in Figure 6. For disassembly of the steering column lock 30, the lock bolt 56 may be withdrawn from the aperture 36, as shown in dashed outline in Figure 6, by a special tool, key, or other disengaging means (not shown). When the steering column lock 30 is operated (Figure 7), the lock bolt 56 is moved by the operating mechanism (not shown) into one of the apertures 22 in the lock sleeve 20. Such an arrangement substantially prevents rotation of the tubular portion 10 of the steering column about axis A.

Compared to known designs of steering column locks, the present invention is easy to assemble on the column (the housing sliding on the jacket), has optional features (asymmetrical outwardly directed tabs locating in grooves) which provide self-centring and angular error proofing, and may include the option of disassembly without the need to remove the steering column from the motor vehicle.

Claims

1. A steering column lock for the steering column of a motor vehicle comprising a lock sleeve which is securable to a rotatable portion of the steering column; a tubular jacket surrounding the lock sleeve; a tubular housing surrounding the jacket; the lock sleeve, jacket and housing being coaxial on a common longitudinal axis; the jacket and housing being normally fixed relative to one another and normally rotatable relative to the lock sleeve about the longitudinal axis; the housing having a radially extending bore with a lock bolt slidable therein; the jacket having a radially extending aperture into which the lock bolt normally extends to lock the housing relative to the jacket; and the lock sleeve having a radially extending aperture into which the lock bolt can extend to lock the jacket and the housing relative to the lock sleeve; wherein the lock bolt can be moved radially away from the longitudinal axis to allow the housing to slide in the axial direction relative to the jacket.

2. A steering column lock as claimed in Claim 1, wherein one end of the tubular jacket has a chamfered edge; and wherein the lock bolt has a chamfered edge; the chamfered edges engaging one another during assembly of steering column lock to move the lock bolt radially away from the longitudinal axis.

3. A steering column lock as claimed in Claim 1 or Claim 2, wherein the tubular jacket has an outwardly directed tab which engages a shoulder in a corresponding groove in the tubular housing when the housing and the jacket are normally locked together.

4. A steering column lock as claimed in Claim 3, wherein the tubular jacket has two or more such outwardly directed tabs and the tubular housing has corresponding grooves each with an engageable shoulder, the tabs being asymmetrically spaced around the circumference of the jacket.

5. A steering column lock as claimed in Claim 3 or Claim 4, wherein the or each groove in the tubular housing extends from one end of the housing to the associated shoulder, the width of the or each groove decreasing from the said one end to the associated shoulder.

6. A steering column lock as claimed in any one of Claims 1 to 5, wherein the tubular jacket has a number of inwardly directed tabs for retaining the outer race of a bearing between the inwardly directed tabs and a shoulder formed inside the jacket.

7. A steering column lock as claimed in any one of Claims 1 to 6, wherein the tubular jacket is formed from extruded and machined metallic material.

8. A steering column lock as claimed in any one of Claims 1 to 7, wherein the tubular housing is formed from moulded plastics material.

9. A steering column lock as claimed in any one of Claims 1 to 8, further comprising disengaging means for withdrawing the lock bolt from the radially extending aperture in the jacket.

10. A steering column lock substantially as herein described with reference to, and as shown in, the accompanying drawings.