Variable assist power steering system and flow control valve therefor

Not Applicable A solenoid operated valve with a single inlet for connection to a pump and a control signal outlet for connection to a power assist steering actuator and a bleed port for connection to a pressure control valve. The valve has a poppet rod extending through an annular valve seat, with a pressure equalization passage extending through the poppet and rod to balance the inlet pressure forces acting on the poppet and rod. The valve provides a low residual flow when the solenoid is de-energized and proportionally increases flow as current in the solenoid is increased and gives substantial linearity.