Power steering is another automotive application developed by Bendix Corporation. This is used in conjunction with a conventional type steering gear. The hydraulic power cylinder is mounted at any convenient place where it can be connected to act directly on the steering tie rod or equivalent linkage member (Figure 9.4). Power for steering is applied in the most simplest and direct way as straight-line motion to the existing steering linkage of the vehicle.
The control valve of the two-unit type installation is mounted in one of the ball joints, usually at the Pitman arm. A small movement in the valve serves to open and close the hydraulic ports and thus operate the double acting power cylinder. Installation of the power cylinder and control valve can be made without changing the existing geometry of the steering linkage.
In effect, the existing steering system including the steering gear remains intact. Likewise the system is free to operate entirely by physical effort, when the engine is not running and in the absence of hydraulic pressure.