Apparatus for controlling a power-assisted steering gear in response to vehicle speed

摘要

An apparatus ( 10 ) for helping to turn steerable wheels ( 12 ) of a vehicle comprises a hydraulic power-assisted steering gear ( 16 ). An electric motor ( 92 ) actuates the steering gear ( 16 ). A pump ( 84 ) supplies the steering gear ( 16 ) with hydraulic fluid. A vehicle speed sensor ( 102 ) senses vehicle speed and provides a vehicle speed signal. A controller ( 104 ) is responsive to the vehicle speed signal for controlling the pump ( 84 ). The controller ( 104 ) activates the pump ( 84 ) to supply hydraulic fluid to the steering gear ( 16 ) when the vehicle speed signal indicates a vehicle speed below a predetermined value and the controller ( 104 ) deactivating the pump ( 84 ) when the vehicle speed signal indicates a vehicle speed above the predetermined value.