Patent ID: 6374941
Filing Date: 2002-04-23
Classification: B62D,G01D

Abstract:
A power steering system for a vehicle having at least one steerable wheel, said power steering system comprising:a manually operable steering wheel, a first angle sensing device connected to said manually operable steering wheel, a servo motor connected to said at least one steerable wheel, a second angle sensing device associated with the servo motor, and a control unit for receiving signals from said first angle sensing device and for energizing said servo motor, wherein said first angle sensing device comprises a single digital angle encoder arranged to generate electric pulses of a certain amplitude in relation to changes in an angular position of said steering wheel, wherein said control unit provides said single digital angle encoder with a constant supply voltage and includes a malfunction detecting device connected to said single digital angle encoder, wherein said single digital angle encoder comprises a circuit for establishing a constant analog voltage for reducing said certain pulse amplitude normally delivered by said single digital angle encoder to a suitable check amplitude, and wherein a bottom voltage level of each pulse is above zero and a top voltage level of each pulse is below said supply voltage.