ELECTRIC POWER ASSISTED STEERING MECHANISM

摘要

: ELECTRICAL POWER ASSISTED STEERING SYSTEM An electric power assisted steering system for a automotive vehicle having a torque shaft connecting the vehicle's steering wheel with the vehicle's steering mechanism. Rotary power is applied to the output end of the torque shaft by a low speed, high torque electrical motor through a low gear ratio planetary gear system disposed concentrically about the torque shaft. The electric motor is energized by a power amplifier in response to a torque signal generated by a torque sensor responsive to the magnitude and direction of the torque applied between the input and output ends of the torque shaft. The power amplifier has an antilog gain characteristic eliminating the need for a vehicle speed input to reduce or eliminate the authority of the power steering mechanism a nominal and higher vehicle speeds.