| 摘要 |
<p>PURPOSE:To correctly detect the abnormality of an electric motor in an electric power steering. CONSTITUTION:A microcomputer 24 cuts off the supply of a driving current to an electric motor 17 only for the specified short time, and judges the motor 17 to be abnormal in the case of no fluctuation being generated to steering torque Ts detected by a torque sensor 22 before and after the cutoff of this driving current whereas judges the motor 17 to be normal in the case of fluctuation being generated. Accordingly, in the case of the motor 17 being out of operation due to mechanical lock or the like, the abnormality of the motor 17 is detected, but in the case of steering being out of operation due to front wheels FW1, FW2 hitting curbstones or the like, the motor 17 generates assist force opposed to reaction based on the elasticity of tires, so that the steering torque Ts is fluctuated before and after the cutoff of the driving current. The abnormality of the motor 17 is not thereby detected.</p> |
