| 摘要 |
PROBLEM TO BE SOLVED: To provide a gas alarm and a control method thereof capable of suppressing the characteristic deterioration of a gas sensor, and thereby restraining the accuracy decline of an alarm. SOLUTION: A gas alarm 1 determines gas leakage by an output obtained from the combustion of detection target gas by a contact combustion type gas sensor 21. In the gas alarm 1, a determining unit 13 determines whether or not an absolute value of the output from the contact combustion type gas sensor 21 is a first threshold value or above, and an alarm unit 30 gives an alarm of the gas leakage when the absolute value is the first threshold value or above. Also, the determining unit 13 determines whether or not the absolute value of the output from the contact combustion type gas sensor 21 is a second threshold value or above which is higher than the first threshold value. A sensor drive control unit 11 decreases a voltage value applied to the contact combustion type gas sensor 21 by controlling a bridge drive circuit 22, when the absolute value of the output from the contact combustion type gas sensor 21 is the second threshold value or above. COPYRIGHT: (C)2012,JPO&INPIT |
