| 摘要 |
PURPOSE:To enable the operation of an air purifier before a room is filled with tobacco smoke, by sensing a sound produced by lighting a match or striking a lighter and by operating the air purifier. CONSTITUTION:A sound signal inputted from a microphone 1 fitted to an air purifier is inputted in a frequency analyzing part 4 through an amplifying part 2 and a wave filtering part 3. The frequency spectrum of a sound produced by lighting a match and that of a sound produced by striking a lighter have been stored in a judging part 5. In case where the frequency spectrum of the sound signal analyzed in the analyzing part 4 is judged to be one of the stored frequency spectra, a signal is sent to a controlling part 6. The part 6 operates a ventilating part 7 when it receives the signal sent from the judging part 5. Thus, the air purifier can be worked before a room is filled with smoke. |
