| 摘要 |
PURPOSE:To prevent the runaway of a robot arm, etc. and to improve the safety by setting a time point adversely proportional to the deviation value to a timer and monitoring the feedback of a feedback signal based on said set time. CONSTITUTION:The drive and stop of a motor 2 are controlled by a control part 4 consisting of a microcomputer circuit. A timer 6 is connected to the part 4 to monitor the feedback of a feedback signal (f) sent from an encoder 3. The part 4 calculates a time T adversely proportional to the deviation and sets it to the timer 6. The timer 6 is reset by the signal (f) sent from the encoder 3 after starting with transmission of a deviation command (u). If the time is up with no reset input, a fault detection signal (i) is delivered to the part 4. The part 4 decides a fault of the encoder 3 when an interruption of the signal (i) is applied and then stops the drive of the motor 2. |
