| 摘要 |
PURPOSE:To maintain a stable flame detecting characteristic without generating the secular change of electric current for flame detection for a long period of time by using an Fe-Cr-Al alloy added with a prescribed ratio of Ti or.Ti and Zr and (or) Nb as an electrode for a flame sensor. CONSTITUTION:The metallic electrode 4 is inserted into a flame 3 of a gas burner or petroleum burner. Slight current flows through the inside of the flame 3 to the electrode when an AC voltage is impressed between a burner base body 2 and the electrode 4. The slight current flowing therethrough in this stage is detected and the ignition condition of the flame is detected. The metallic electrode consisting of 3-8wt% Al, 18-28wt% Cr, 0.2-0.6wt% Ti and the balance substantially Fe or the metallic electrode consisting of 3-8wt% Al, 18-28wt% Cr, 0.2-0.6wt% Ti, 0.1-0.5wt% one or two kinds in total of Zr and B and the balance substantially Fe is used as the electrode 4. The good response characteristic is thus maintained over a long period of time. |
