| 摘要 |
<p>PURPOSE:To prevent a humidity sensor from being contaminated by the peripheral atmosphere and improve its sensitivity as well prolong its life by a method wherein the humidity sensor housed in a case is intermittently made to contact to the peripheral atmosphere outside the case by using a fan. CONSTITUTION:A humidity sensor 1 is housed in a case 4 having an air inlet port 4a and an exhaust port 4b. In addition, a fan 5 to make the peripheral atomsphere intermittently contact to the sensor 1 is provided and operated by a drive circuit 7. In said constitution, the fan 5 intermittently supplies the peripheral atmosphere into the case according to the signal from the drive circuit 7. The humidity sensor 1 detects the humidity of the peripheral atmosphere when contacting thereto and sends out a humidity signal to a converter circuit 6, which converts it into an electric signal and sends it out to an output terminal OUT. Thereby, the contamination of the sensor 1 is reduced, so that its sensitivity can be improved as well as its life can be prolonged.</p> |
