| 摘要 |
A diagnosing operation controlling portion compares the magnitude of change of a control instruction value that controls the dislocation of a valve stem to a reference value that has been set in advance, and stops the malfunction evaluation operation in a diagnosing portion if the magnitude of change per unit time in the control instruction value exceeds a reference value. If the magnitude of change per unit time in the control instruction value exceeds the reference value, then the evaluation may be the same as for a case wherein a stick-slip has occurred, even if the operation is functioning properly. In contrast, it is possible to prevent incorrect stick-slip evaluations by stopping the operation of the diagnosing portion when the magnitude of change per unit time in the control instruction value exceeds a reference value. |
