POWER STEERING SYSTEM

A power steering control valve includes relatively rotatable inner and outer valve members. A power steering resistance control system resists relative rotation between the inner and outer valve members with a force which varies as a function of variations in vehicle speed. The power steering resistance control system includes a force transmitting member which rotates with the outer valve member and moves axially relative to the inner and outer valve members. Fluid pressure is applied against the force transmitting member urging it in a first direction along the axis of rotation of the valve members. Fluid pressure is also applied against the opposite side of the force transmitting member to urge it in the opposite direction along the axis of rotation of the valve members. A speed responsive control valve, connected with a fluid return conduit for the power steering valve is operable to vary the fluid pressure applied against the opposite side of the force transmitting member as a function of variations in vehicle speed. At relatively low vehicle speeds, the fluid pressure force applied against the opposite of the force transmitting member is relatively large and it is easy to actuate the steering control valve. As vehicle speed increases, the fluid pressure force applied against the force transmitting member decreases and the resistance to actuation of the steering control valve increases.