| 摘要 |
PURPOSE:To detect abnormality assuredly without making any erroneous decision through a simple circuit by deciding an abnormality when the abnormality generating frequency within the 1st set time is higher than a prescribed level and at the same time the abnormality generating frequency within the 2nd set time in higher than a prescribed level respectively. CONSTITUTION:The abnormality generating frequency within the 1st prescribed time T1 between the working start time point t1 of a timer and a time point t2 is less than the 1st prescribed level. That is, the timer is set at the same time T1 every time the time T1 elapses as long as an actuator has the normal actuation. While the timer is immediately set at the 2nd prescribed time T2 if the abnormality generating frequency reaches the 1st prescribed level at a time point t3 before the time T1 elapses. Then the generation of abnormality is immediately decided if the abnormality generating frequency reaches the 2nd prescribed frequency before elpase of the set time T2, i.e., at a time point t4. Thus it is possible to avoid the wrong decision due to the temporary generation of abnormality owing to noises, etc. |
