| 摘要 |
PURPOSE:To stabilize the action of an oxygen defficiency safety device and to prevent the occurrence of incomplete combustion during low O2 concentration, by a method wherein thermocouples are respectively located in the vicinity of a main burner and a pilot burner, and the theremocouples are connected to each other so that thermoelectromotive forces have reverse polarity to each other. CONSTITUTION:With an ignitor actuated, flame 6 is formed and a thermocouple 9 is heated. Simultaneously, by means of the flame 6, flame is formed at burner ports 21 of a pilot burner 21, and a thermocouple 20 is heated. Pertaining to thermoelectromotive force, generated as a result of each thermocouple being heated, in the case of O2 concentration being 21%, that of the thermocouple 20 is 20mV, and that of the thermocouple 9 is 10mV. In case O2 concentration in atmosphere is decreased under the set condition described above, a decrease in an atmospheric temperature in a combustion chamber 2 is low, and thereby a change in the electromotive force of the thermocouple 9 is low. However, the flame of a pilot burner 21 is extended or lifted up in low O2 concentration atmosphere, and an amount of heat applied on the thermocouple 20 is decreased. This reduces the electromotive force of the thermocouple 20, decreases a difference in an electromotive force between the thermocouples 9 and 20, and as a result, a safety valve 14 is actuated before CO is produced. |
