| 摘要 |
PROBLEM TO BE SOLVED: To solve a problem that, if a mechanical apparatus driven by a motor is brought into abnormal operating state due to malfunction of the apparatus, mixing of foreign matter, or the like, load torque is increased and thus driving torque is increased for continuing operation; and this phenomenon induces damage to the malfunctioning part of the apparatus or damage to the mechanical apparatus due to the mixed foreign matter. SOLUTION: The load torque of the mechanical apparatus driven by the motor is computed by a motor controller, and the differentiated value of the load torque is calculated by a differentiator built in the motor controller. The calculated differentiated value of the load torque is compared with a specified abnormal level for differentiated value of load torque as needed. If abnormal increase in load torque due to malfunction of the mechanical apparatus or the like is detected, that is taken as an anomaly in the mechanical apparatus and the motor controller is operated so as to suppress increase in torque command for driving the mechanical apparatus. Thus, damage to the mechanical apparatus is prevented from occurring. |
