Abstract: The invention provides a method for controlling valve stiffness in a power steering system. The method includes the step of engaging a pinion and a spool shaft with respect to one another for turning at least two wheels of a vehicle in response to rotation of a steering wheel from an on-center orientation. The method also includes the step of variably assisting movement of the pinion with a hydraulic power steering device having a valve movable between a closed configuration and an open configuration. The method also includes the step of moving the valve from the open configuration to the closed configuration in response to rotation of the spool shaft relative to the pinion from an on-center orientation to assist the pinion in rotation for turning the at least two wheels.

Abstract: A method of determining a direction of a power boost applied to a power cylinder of a variable effort power steering system includes measuring a pressure of a hydraulic fluid between a pump and a control valve. A first position of the hand wheel is detected and initialized when the pressure is within a pre-defined equilibrium pressure range. A second position of the hand wheel is detected in response to rotational movement of the hand wheel. The first position and the second position of the hand wheel are measured in cumulative degrees rotated left or right of a on-center orientation of the hand wheel. The second position is subtracted from the first position to obtain a differential value representing the direction of the power boost. A negative differential value represents a first direction and a positive differential value represents a second direction of the power boost.

Abstract: A power assist steering system including a valve housing and a proportional control valve supported within the valve housing, further includes a pressure transducer arranged with respect to the proportional control valve for determining an amount of actuation of the proportional control valve. A pressure signal is sent from the pressure transducer to a control for determining an amount of current to be sent to an electromagnetic apparatus within the power assist steering system for overcoming a pull force.

Abstract: The invention provides a method for controlling valve stiffness in a power steering system. The method includes the step of engaging a pinion and a spool shaft with respect to one another for turning at least two wheels of a vehicle in response to rotation of a steering wheel from an on-center orientation. The method also includes the step of variably assisting movement of the pinion with a hydraulic power steering device having a valve movable between a closed configuration and an open configuration. The method also includes the step of moving the valve from the open configuration to the closed configuration in response to rotation of the spool shaft relative to the pinion from an on-center orientation to assist the pinion in rotation for turning the at least two wheels.