Mechanical Steering Components, Basic Function - GF46.00-P-1000B
Model all (4xWD)
Model all (CAR)
Example illustration of passenger car mechanical steering components
Example illustration of off-road vehicle mechanical steering components
Overview
This document contains information on:
- General
- Function
- Steering wheel
- Steering column tube
- Steering column
- Rack-and-pinion steering
- Recirculating ball steering
- Tie rod
General
Mechanical steering components describe the mechanical interaction between steering components during the transfer of steering forces.
Function
In the electrical power steering system, the system, the driver and an actuator motor as an electromechanical auxiliary power steering system act on the vehicle's steering ability.
The following components are involved in mechanically implementing a steering maneuver:
- Steering wheel
- Steering column tube
- Steering column
- Rack-and-pinion steering
- Recirculating ball steering
- Tie rod
Steering wheel
The driver influences the vehicle's steering ability using the steering wheel. The steering wheel angle is adjusted and the steering torque transferred via the steering wheel.
The steering wheel angle describes the twisting angle of the steering wheel measured from the straight-ahead position. The steering wheel angle is positive on a left turn.
The steering torque describes the steering forces applied manually to adjust the steering wheel angle. The steering torque also has a positive value on a left turn.
Steering column tube
The steering column tube surrounds the steering shaft and steering column; it includes the mechanical or electrical adjuster unit.
Steering column
The steering column routes the torque to the rack-and-pinion steering. It is used to mechanically transfer the steering movement to the rack-and-pinion steering through the steering shaft and drive pinion.
The steering column adjuster unit enables the steering to be aligned to the driver.
Rack-and-pinion steering
The rack-and-pinion steering is responsible for transferring the steering torque in its role as steering gear. The toothed rack positioned perpendicular to the vehicle's longitudinal axis transmits the steering movement via the tie rods and the steering arms to the steering knuckles.
A drive pinion - which is connected to the steering column tube in a torque-proof manner via a joint coupling - is used to transfer the steering torque to the toothed rack.
The toothed rack tooth pitch enables a variable steering ratio (with code 213 (Direct-Steer system)).
The gear ratio is defined by the ratio of turns on the drive pinion to the toothed rack stroke.
Recirculating ball steering
The recirculating-ball steering functions as a steering gear to transfer the steering torque. The steering shaft is located in the steering gear, which has a thread-like track milled into it. The track contains steel balls, which connect the steering shaft to the steering nut. Turning the steering shaft moves the steering nut which guides the working piston on the steering shaft. The movement of the working piston is forwarded by a gearing on the pitman arm shaft, which also has a gearing, thereby inducing a rotary movement in the pitman arm shaft. The rotational movement of the pitman arm shaft is forwarded over the pitman arm to the tie rod.
Tie rod
The tie rod connects the rack-and-pinion steering to the steering knuckle via the tie rod end and, in this way, transfers the toothed rack stroke to the front wheels.
| Additional basic functions | |||
| Rack-and-pinion steering, basic function | Model all (CAR) | GF46.20-P-1001A | |
| Steering column lock control unit, basic function | Model all (CAR) | GF80.57-P-9891A |