| 摘要 |
PROBLEM TO BE SOLVED: To sufficiently use the ability of catalyst and to exactly detect the service life of catalyst by storing an ozone sensor output voltage in the beginning of device operation start, comparing an ozone sensor output voltage at the time of operating and turning off an ozone lamp when the difference between both the voltages is higher than a prescribed set value. SOLUTION: When a power source switch 14 is turned on and operating is started, a control circuit 18 resets the integral turn-on time of an ozone lamp 7. Then, a circulation fan 8 is operated. After the lapse of prescribed time, the output voltage of an ozone sensor 10 is written in a non-volatile memory 30. Next, the turn-on time of the ozone lamp 7 is set to '0' and the ozone lamp 7 is turned on. Then, the measurement of lamp turn-on time is started. The output voltage of the ozone sensor 10 is detected and when the turn-on time of the ozone lamp 7 does not reach the integral turn-on time, that detected voltage is compared with the stored ozone sensor output voltage. When the detected output voltage is higher than the stored value, the ozone lamp 7 is turned off. |
