| 摘要 |
490,938. Screw - and nut gearing. DOUGLAS, J. G. Feb. 23, 1937, Nos. 5347, 7710, and 26701. [Class 80 (iii)] In screw-and-nut steering gear in which balls roll between screw and nut each ball 6 fits and rolls in two grooves in an endless path the whole of which is exposed to the worm. The screw 3 on the steering column is rotated to drive a nut 1 in a casing 2 the movement of the nut being transmitted to the road wheels in the manner described in Specification 361,204. The path of the balls is a single helix joined at its ends by a transfer part 7 which may be formed by a member 10 or comprise merely a slot in the nut. The balls are turned through a right-angle from the helix to port 7 and from the port to the helix, by curved surfaces 8a on guide blocks 8, Fig. 16, inserted in the nut. In a modification the steering wheel rotates the nut, the axial movement of the screw being transmitted to the road wheels. |
