Electronic Variable-Assist Power Steering

The power steering unit is designed to reduce the mount of effort required to turn the steering wheel. Conventional Power steering system operate by means of hydraulic pump driven by abelt from the crankshaft pulley. This pump provides the fluid pressure and flow needed to operate the system. Maximum pressure line and return line connect the pump to the system. the hydraulic pressure provides most of the force needed for steering. The remaining steering effort provides needed driver feel for googd steering control.
The basic purpose of an electronic variable assist power steering system is to provide maximum power assist for light steering effort during low-speed vehicle maneuvering, such as parking, and minimum power assist for firm steering wheel control and directional stability at higher speeds.

Essendtially, the system is made up of microprosessor-based control modul the recives information on vehicle speed sensor. The control modul prosesses this information and signal an electrically controlled actuator valve in regard to annamount of assist required. During parking and low-speed operation, the control module sends a signal to actuator valve steeper motor, positioning the valve spool to allow for maximum power assist. As vehicle speed increases, the control module signals the actuator valve spool to open gradually, diverting an increased amount af fluid, therefore providing lass power assist. At cruising speeds, maksimum power assist is supplied, providing better road feel.