| 摘要 |
<p>A motor vehicle steering column (10), Figure 2, including a tubular lower mast jacket (12) anchored on a vehicle body, a tubular upper mast jacket (14) telescoped inside the tubular lower mast jacket, a plurality of steel spheres (44) interference fitted in an annulus (38) defined at an overlap between the mast jackets, and a plastic ball sleeve (40) in the annulus having pockets (42) loosely receiving respective ones of the steel spheres. The ball sleeve has a plurality of notches (50A,50B) in an edge (46) thereof exposed through an outboard end (22) of the lower mast jacket. An anti-rotation bracket (54) is welded to a stationary mounting bracket (20) attached to the lower mast jacket and includes a plurality of tangs (60A,60B) which project through the outboard end of the lower mast jacket into respective ones of the notches (50A,50B) in the ball sleeve whereby rotation of the ball sleeve about a longitudinal centreline of the steering column is positively foreclosed. With the ball sleeve blocked against rotation, the magnitude of turning moment which must be applied to the upper mast jacket to twist it relative to the lower mast jacket, e.g. to defeat an anti-theft system on the steering column, is sufficient to prevent defeat of the anti-theft system without also causing collateral steering column damage sufficient to render the vehicle undriveable anyway. <IMAGE></p> |
