| 摘要 |
<p>PROBLEM TO BE SOLVED: To detect the lock state of an electric motor in the non-steering state, and to inform a driver of the state before steering to call for attention. SOLUTION: When a steering torque T is smaller than a predetermined setting valueα, the state is judged to be non-steering state, so that FETs 41, 43, and 45 are controlled to be off state and FETs 42, 44 to be on state, and then a closed circuit comprising the FET 42, an electric motor 9, the FET 44, a left direction current detection resistance RL, and a right direction current detection resistance RR is formed, and respective current detection signals iL, iR in this state are monitored. And, when these current detection signals iL, iR are zero together, the electric motor 9 is usually minutely rotated by the disturbance from floor to generate counter electromotive force. However, when the counter electromotive force is not occurred in spite of receiving the influence of the disturbance, the electric motor 9 is regarded as having been fallen into a lock condition, the abnormal is noticed to a driver and also the power supply from an electric source 13 to a bridge circuit 36 is stopped.</p> |
