Patent ID: 7711465

Claim:
A variable steering ratio control device that controls a steering angle of steered wheels in a steering system by applying a driving force to a steering input of the steered wheels, comprising: an input torque obtaining portion that obtains an input torque that is applied to a steering train of the steering system by external forces; an operation torque estimating portion that calculates an operation torque that a driver applies to a steering wheel; a phase adjusting portion that sets a phase of a target steering angle of the variable steering ratio control device to a first phase when both a first condition and a second condition are satisfied, and sets the phase of the target steering angle of the variable steering ratio control device to a second, different phase when at least one of the first and the second conditions is not satisfied, wherein the first condition is satisfied when the operation torque is smaller than a first predetermined value and the second condition is satisfied when the input torque is smaller than a second predetermined value; and a motor that applies driving force to the steering input of the steered wheels based on the target steering angle.