| 摘要 |
PROBLEM TO BE SOLVED: To provide an optical fire alarm system for eliminating the erroneous detection of fire detection caused by shaken-off dusts by shaking off dusts accumulated in a smoke detection chamber by vibrating the smoke detection chamber, and then settling down the dusts.SOLUTION: An optical fire alarm system is configured to periodically output a cleaning signal for continuously outputting a sound wave in a non-audible band from a speaker in a fixed cleaning period to shake off dusts in a smoke detection chamber, and to disable a smoke detecting function in a smoke sensing processing part in a predetermined idle period exceeding the cleaning period after the output of the cleaning signal. |
