| 摘要 |
A rack and pinion steering mechanism for a vehicle comprises a rotatable steering input. The rack is displaceable to effect vehicle steering, and drive means drivingly interconnects the input and the rack to effect displacement of the rack upon rotation of the input means. The drive means comprises an axially fixed primary pinion, a gear portion on the rack and gear means interposed between the primary pinion and the gear portion of the rack. The gear means includes at least one helical pinion gear and the primary pinion, or gear portion of the rack has helical teeth meshing with the helical teeth of at least one helical pinion gear. A cam means is provided responsive to rotation of the primary pinion to effect axial displacement of the helical pinion to produce a variation in the movement ratio between the primary pinion and the rack. |
