| 摘要 |
PURPOSE:To eliminate the fluctuation in an alarm level for gas without being affected by ambient temp. and ambient humidity by connecting a gas sensitive element and temp. sensitive element in series, and measuring the resistance value of the gas sensitive element at the junction thereof. CONSTITUTION:A heater 1 and a lead pin 2 for the heater are fixed and connected and a voltage is impressed thereto. The gas sensitive element 3 aand a humidity sensitive element 8 are thereby heated. The gas sensitive element 3 is connected to a lead wire 4 and a lead pin 5 and the humidity sensitive element 8 is connected to a lead wire 9 and a lead pin 10. The electric resistance values of the respective elements 3, 8 are measured. The gas sensitive element 3 and the humidity sensitive element 8 are connected in series and the voltage is impressed at both ends thereof, then the ratio between the resistance value of the gas sensitive element 3 and the resistance value of the humidity sensitive element is made constant and the output voltage is made constant without being affected by the ambient temp. and ambient humidity. Since both sensitive elements are combined in the above-mentioned manner, the gas concn. characteristic is stably measured without being affected by the ambient temp. and humidity.
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