| 摘要 |
PURPOSE:To detect with sure the fault of an energizing circuit which is intermittently operated by duty pulse and to issue warning. CONSTITUTION:A pair of trigger pulse generating circuits 13 and 14 are provided, and an operational pulse signal 23a for an energizing transistor and an output pulse signal 21a from the transistor are inputted into the pair, respectively. A pair of counter circuits 11 and 12 consisting of three-stage of flip-flop 111-113 and 121-123 are provided, and a trigger pulse 13a is inputted to both the first stage of the counter 11 and a reset terminal of the counter 12, and a trigger pulse 14a both to the first stage of the counter 12 and to a reset terminal of the counter 11, respectively. If the output pulse signal 21a does not appear regardless of the existence of the operational pulse signal, the counter 12 begins to count the input trigger pulse 14a, and a count up signal 12a is outputted as the warning signal 13a by way of an exclusive OR gate 13. |
