| 摘要 |
<p>PURPOSE:To obtain a humidity detector which has high accuracy in a wide range of humidity region over a long period of time at an under a high temp. and high humidity by using a block which is series-connected with a capacitor and is further combined with fixed resistors in series or parallel or series-parallel for a humidity sensor consisting of a porous body formed by dispersing carbon powder in quartz glass. CONSTITUTION:The humidity sensor 31 consisting of the porous body dispersed with the carbon particles in the glass is formed by dispersing the carbon particles into a sol prepd. by hydrolysis of Si(OR)4 [R is an alkyl group], gelatinizing the sol and boiling the gel in water after drying and sintering. The block 3 which is series- connected with the capacitor 32 and is further connected with the fixed resistors in series, parallel or series-parallel is used for the feedback resistance of a detection amplifier. A signal source is applied from an oscillation circuit 1 and the amplification factor of the detection amplifier 2 is changed by a change in the resistance value of the sensor 31 and, therefore, the analog signal proportional to a change in the relative humidity detected by the sensor 31 is obtd. when an amplifier output signal is supplied to a current rectifier circuit 4. The humidity detector which is wide in the range of the moisture sensitive characteristics and has the high accuracy over a long period of time is obtd. according to this constitution.</p> |
