Patent ID: 9738308
Date: 2017-08-22
CPC Classifications: B62D

Claim:
1. An electric power steering device, comprising: a steering assist torque applying device; and a control device configured to control a steering assist torque to be applied by the steering assist torque applying device to a steering apparatus for a vehicle, wherein: the control device comprises a storage device configured to store a relationship between a basic target return speed, which increases in magnitude as a magnitude of a steering angle increases, and the steering angle, and is configured to calculate, when a steering wheel is being returned toward a neutral position, the basic target return speed based on an actual steering angle and the relationship, and to apply feedback control to the steering assist torque so that a return speed of the steering wheel reaches the calculated basic target return speed; and the control device is configured to calculate, when the steering wheel is being returned toward the neutral position, a transitional target return speed, which gradually increases in magnitude and gradually approaches the basic target return speed as a magnitude of the actual steering angle decreases, and to apply, when a magnitude of a difference between the basic target return speed and the transitional target return speed is more than a reference value, feedback control to the steering assist torque so that the return speed of the steering wheel reaches the transitional target return speed in place of the calculated basic target return speed.