| 摘要 |
PURPOSE:To detect exactly a gaseous component in accordance with the antiresonance compensated of a temp. fluctuation by changing an oscillation frequency according to temp. and eliminating the influence of the temp. on the antiresonance. CONSTITUTION:An oscillating body 8 of a resonance vessel 4 of a Helmholtz type is driven by the oscillation frequency corresponding to the antiresonance frequency having temp. dependency according to the temp. by an oscillating circuit such as free running multivibrator or the like using a thermistor, etc. If the position of an interferring body 10 is adjusted in such a way that the acoustic wave through a sound releasing hole 6 by said driving is antiresonated and the sound is thus eliminated, a gaseous component is exactly detected in accordance with the antiresonance compensated of a temp. fluctuation. |
