| 摘要 |
PURPOSE:To make it possible to positively detect the existence or non-existence of a flame by providing ceramic sensor at the tip end portion of a flame detecting electrode and/or at parts other than the tip end thereof. CONSTITUTION:A cylindrical ceramic body 6 made of a solid electrolyte having an oxygen ion conductivity at high temperatures, such as zirconia or the like, is mounted on the tip end of a heat-resisting and conductive pipe-shaped flame detecting electrode 1 made of a material such as an SiC heat-resisting metal or the like. On both inner and outer surfaces of the ceramic body are provided porous electrodes 7 and 8 made of platinum, for example, and hence a predetermined number of oxygen sensors are constituted. Further, at further outer side of the outside electrode 7 is provided a filter structure port 9. The outside electrode 7 is brought into contact with the flame atmosphere. As a result, the flame 16 is spaced apart from the tip end of the burner 15, and even when the flame 16 cannot be detected, the flame can be detected by the oxygen sensors 6, 7 and 8. |
