| 摘要 |
PURPOSE:To contrive to cut-off the gas supplying and improve the safety at the back fire of a main burner by a method wherein a thermoelectric couple heated by a flame of a pilot burner is provided, moreover, another thermoelectric couple is provided on the main burner throat part where a flame is formed when the back fire occurs at the main burner. CONSTITUTION:A thermoelectric couple 6 is connected with a thermoelectric couple 4 in parallel for being impressed by the back electromotive force, the thermoelectric couple 4 attracts the valve which opens a gas supplying circuit for a pilot burner 3 and a main burner 5 by exciting an electromagnet of a safety valve 2 due to the generation of thermoelectromotive force at the heating by the pilot burner 3. During the burning of the pilot burner 3 and the main burner 5, when the main burner 5 is backfired while the flame of the pilot burner 3 is still held, the thermoelectric couple 6 is heated to a throat part 5a by the backfired flame. The thermoelectromotive force is generated,then the safety valve 2 is impressed by the electromotive force having inverse direction which is impressed on the safety valve 2 for the thermoelectric couple 4 at the pilot burner 3 side. The valve is removed from the electromagnet of the safety valve 2, the gas supplying line for the main burner 5 and the pilot burner 3 is cut-off, then the flame is extinguished. |
