Patent ID: 7559405

Claim:
A controller of an electric power steering device, which comprises a motor applying a steering assist force to a steering system of a vehicle and at least one torque sensor detecting a steering force applied to a steering wheel, and controlling said motor based on an output value of said torque sensor, characterized in that: said controller comprises a torque input processing unit comprising at least one torque abnormality detecting means for detecting an abnormality of an output value of said torque sensor and an substitute torque value calculating means for calculating an substitute torque value based on past normal output value of said torque sensor before said output value of said torque sensor becomes abnormal, and a torque fault confirming means for confirming a determination that said torque sensor is out of order in the case that said abnormality of said output value of said torque sensor runs on for a fixed time, said controller controls said motor based of said substitute torque value in place of said output value of said torque sensor in case that said output value of said torque sensor is abnormal, even before confirming said determination that said torque sensor is out of order.