| 摘要 |
<p>PURPOSE:To instantly make a judgement on failures by providing both a counter in which counting is kept on at all times while a count valve is returned back to its initial condition every time when the detected signal rises or falls and a comparator which generates the abnormal signal when counting goes on beyond a specified value. CONSTITUTION:Since pulses are generated from an air flow sensor 7 at the time of normal operations, a counter is preset every time when it rises, and the counter will never indicate a value less than a specified value A even if count-down is begun after it has been preset. No pulse is however generated at the time of abnormal conditions, and no timing for rising is therefore available, when the count-down of the counter is kept on, the count value will soon be less than the specified value A. At this point, the condition is judged abnormal by an abnormality detection device (comparator) 8 which monitors the count value of the counter. A lamp 10 is thereby lit while warning actuation is provided based on the result of judgement.</p> |
