| 摘要 |
PURPOSE:To suitably detect a malfunction over a wide range from a small armature current to a large armature current by dynamically varying a reference value in response to the amplitude of the armature current. CONSTITUTION:A double system having first and second driving units I and II is provided, and first and second current sensors 16a, 16b for detecting the input currents of the motor driven servo motors 1a, 1b of the driving units are provided. The outputs of the sensors 16a, 16b are input to a point 17 for differentiating the outputs and a point 18 for adding the outputs. The output of the point 17 is input to an absolute value circuit 19, the output is connected to the first input of a comparator 20, and the output of the point 18 is connected to the second input of the comparator 20. Then, the output of the comparator 20 becomes a malfunction detection output. |
