| 摘要 |
<p>PROBLEM TO BE SOLVED: To prevent the motor output from being stopped due to rack stroke end and the like in the case other than failure by providing a circuit for detecting motor overcurrent at a low level for limiting duty and a circuit for detecting motor overcurrent at a high level for detecting failure. SOLUTION: An overcurrent detection circuit 40 for detecting failure and an overcurrent detection circuit 41 for limiting duty are provided. The detected current value of the overcurrent detection circuit 41 is set to be greater than the rated current level and less than the detected current value of the overcurrent detection circuit 40. When the overcurrent detection circuit 41 detects overcurrent, a control signal DS that limits duty to an FET gate drive circuit within a motor control circuit 37A is output. Also, when the overcurrent detection circuit 40 detects overcurrent, a disconnection signal CS that blocks the driving of a motor 20 to a gate circuit within a motor drive circuit 37B is output, turning the relay 13 OFF to stop output of the motor 20.</p> |
