| 摘要 |
PROBLEM TO BE SOLVED: To provide a flame detector capable of improving detection performance due to a view field range expansion by improving a circulation channels of cooling air, and stabilizing a flame by supplying the cooling air to the flame through an outer cylinder slit.SOLUTION: A flame detector includes: a lighting portion having a lighting optical fiber 6; a transmitting portion having a transmitting optical fiber 36 connected with the lighting optical fiber 6 and transmitting optical information; an outer cylinder 1 for housing the lighting portion and the transmitting portion; and air passages 40 and 41 introducing cooling air from a head box to circulate. The lighting portion has a lighting head 2, a supporting member 3 for supporting the lighting head 2 between the outer cylinder 1 and the supporting member 2, and a lighting ensuring member 4 formed with an opening portion 46 for ensuring lighting. The outer cylinder 1 is formed with a slit 5 in an outer cylinder circumferential direction, and jets cooling air to the outside through the slit 5. The air passage 41 is formed in an outside longitudinal direction of the lighting head 2 till the lighting ensuring member 4, and the cooling air is jetted to the outside from the lighting ensuring member 4. |
