| 摘要 |
PURPOSE:To prolong the life of a CO sensor by allowing the CO sensor to operate every predetermined time under a condition where the concentration of carbon monoxide is not raised and to operate continuously under a condition where the concentration thereof is raised thereby to carry out detection. CONSTITUTION:A detection circuit 36 receives detected data regarding the concentration of carbon monoxide from a CO sensor 37 in remaining one minute, that is, after lapse of nine minutes of ten minutes in which the detection circuit 36 receives a driving pulse, and stores the detected data in a RAM 38. A comparator 39 transmits the result of comparison between data detected at this time and data detected in the preceding time to a control circuit 41. Further, a comparator 40 compares data detected at this time with data regarding the value of the concentration of carbon monoxide which is dangerous to a human body, the transmits the result of comparison to the control circuit 41. If the result of comparison of the comparator 39 is 'rise in CO concentration', a continuous operational signal is transmitted to the detection circuit 36, and an inoperative signal is transmitted to a timer 35. Further, if the comparison result of the comparator 40 is 'above the dangerous level', the control circuit 41 transmits a combustion stop signal to a control circuit 43 and actuates an alarming device 42. As a result, it is possible to prolong the life of the CO sensor. |
