| 摘要 |
PURPOSE:To make the resistance temp. characteristic of a gas detecting element the same as the resistance temp. characteristic of a temp. compensating element to improve the sensitivity by using stannic oxide and zinc oxide as essential components, adding a specific ratio of an osmium compd. thereto and sintering the mixture for the gas detecting element. CONSTITUTION:The osmium compd. is compounded in a 0.1-3wt% range with a compounded compsn. consisting essentially of the stannic oxide and zinc oxide and the mixture is sintered to constitute the gas detecting element. The compounding ratio of the osmium compd. is so adjusted that the electric resistivity of the gas detecting element is made the same as the electric resistivity of the temp. compensating element. A heating resistor 3 is provided to one surface of a substrate 1 and the gas detecting element 6 and the temp. compensating element 8 are provided on the other surface. The gas detecting element 6 and the temp. compensating element 8 are heated under the same conditions and are constituted into a bridge circuit. The measured value is taken out of an output terminal O. Since the specific gas detecting element is used, the detection of gaseous propane, etc. with high accuracy without being affected by the fluctuation of an electric power source and the change of environmental temp. is made possible. |
