| 摘要 |
PURPOSE:To recognize incomplete combustion, deterioration and failure of a sensor by the same sensor, by installing heat-resistant electrodes as sensing parts, on the inner and the outer peripheral surfaces, respectively formed below the specific value of each circumference. CONSTITUTION:When incomplete combustion is caused by some reason, the combustion flames on a main burner 4 are elongated until they can contact with an electrode 9 on the outer circumference, the resistance of a sensor 1 is increased because of lowering of the temperature in combustion flames. In addition, the ratio of inner and outer partial pressure of oxygen is decreased, electromotive force is decreased, and the current which is necessary to hold a solenoid-operated valve in an open condition does not flow, so that the solenoid-operated valve is closed to stop supplying of gas. With such an arrangement, incomplete combustion and extinguishing of flames in a gas burner of such as a gas and an infrared rays stoves, in which the combustion flames are short, can be detected. Besides, an abnormal condition such as deterioration and breakage of a sensor can be detected by the same sensor. |
