Rack and Pinion Gear Functions

Rack and Pinion Gear Functions





NOTE: Numbers in parentheses ( ) indicate a component or tool in the associated illustration.

BASIC FUNCTIONS
The steering wheel movement is transmitted to the rack (7) by the drive pinion (4b) and then to the wheels via the track rods.

The drive pinion has a spiral-shaped toothing. As an increasing number of teeth mesh at the same time the rack-and-pinion steering is wear-resistant and has a very low noise level.

STEERING GEAR RATIO AND TEETH
The variable steering gear ratio is achieved by the effective diameters (d1 and d2) which result from the shape and angles of the toothing.

The rack is designed indirect in the center area (X). The rack-and-pinion steering becomes increasingly more direct in the outer areas (Y).

The difference between the ratio in the center area (X) and the ratio in the outer area (Y) is:
- Approx. 27 % for standard steering
- Approx. 17 % for sports suspension