Steering: Description and Operation

Power Steering


Oil flow through the control valve is continuous. When the wheels are in the straight ahead position, low oil pressure is applied to each side of the piston. As the steering wheel is turned, a small torsion bar within the assembly, allows a few degrees of rotation before actually turning the pinion. This rotation is used to open and close ports in the control valve, to ensure the torsion bar is twisted, the hydraulic pressure directed to one side of the piston is also increased, from 40 inch lbs., to a maximum of 1200 inch lbs., returning to minimum when the load on the torsion bar from the setting wheel is zero. The increase in pressure being proportional to the twist in the torsion bar.
Hydraulic pressure is provided by a vane-type, non-submerged pump, driven directly from engine auxiliary shaft.
To prevent the hydraulic pressure from exceeding 1200 inch lbs., a flow control valve is connected to the outlet port of the pump.