| 摘要 |
PURPOSE:To suspend the action of an instrument by sensing the state of abnormal combustion including diffused combustion, by a method wherein a plurality of flame rods is provided on different positions from the tip face of a burner and flame signals to be detected by the flame rods are compared with each other. CONSTITUTION:A phototransistor 29 is turned ON when a flame current is detected by a flame rod 3, which is turned into an inversional input of a comparator 33 through resistances 31, 32. A phototransistor 30 is turned ON when the flame current at the time of abnormal combustion is detected by the flame rod 20, which is turned into a noninversional input of a comparator 36 through resistances 35, 34. The noninversional input of the foregoing comparator 33 and the inversional input of the foregoing comparator 36 are constituted with resistances 38, 37 and 39, 40 respectively. In addition to the above, an output of the comparator is applied to an AND circuit part for driving of a solenoid valve incorporating resitances 41, 42, 43 and a transistor 44. |
