Patent ID: 6334503
Filing Date: 2002-01-01
Classification: B62D,H02H

Abstract:
An electrically operated power steering apparatus for an automotive vehicle having a steering wheel to be operated by an operator of the vehicle and a steerable wheel thereof laying on a road surface, comprising:a torque transmitting system transmitting a steering torque which is applied to the steering wheel by the operator, to the steerable wheel; a motor applying a drive force thereof to the torque transmitting system so as to assist the steering torque; a controlling device controlling an electric power supply to the motor, thereby permitting reduction in a required value of the steering torque with the assist of the drive force of the motor; and a power supply restricting device utilizing a temperature of a heated portion of the electrically operated power steering apparatus which emits heat as a result of the electric power supply to the motor, at a reference point of time, as an initial temperature of the heated portion, utilizing a plurality of electric power-related values each of which is related to at least one of a current and a voltage value of the motor, as a plurality of physical quantities related to temperature increases of the heated portion each of which is an increase of the temperature of the heated portion from that at the reference point of time, and restricting the electric power supply to the motor such that an actual value of the temperature of the heated portion does not exceed a predetermined upper limit thereof.