| 摘要 |
PURPOSE:To detect abnormality before generation of a runaway and to improve greatly the safety by detecting the variation of a feedback amount when a deviation is produced between the set value and the feedback amount and deciding that an operation is in a normal state or in abnormality when a movement is given to set the deviation at 0 or vice versa respectively. CONSTITUTION:An abnormality detector 200 delivers logic 1 through detectos 9 and 10 when the deviation epsilon is larger than the prescribed values of both positive and negative sides respectively. A differentiating circuit 8 differentiates a feedback amount Q and estimates the moving direction of the Q by delivering a variation factor (q). Level detectos 11 and 13 deliver logic 1 when the factor (q) is larger than the prescribed vlues of the both positive and negative sides respectively. While a level detector 12 delivers logic 1 when the factor (q) is close to 0. AND circuits 14-17 deliver logic 1 when the prescribed values have no variation in both increase and decrease directions of the feedback amount with positive and negative deviations epsilon respectively. These outputs are transmitted in the form of alrams or lock signals via delay circuits 18-21. |
