| 摘要 |
PURPOSE:To obtain an effective gas sensor while facilitating the formation of a plurality of catalyst layers by connecting an internal heat sensitive body of a temperature sensor to any two of lead wires piercing an airtight terminal and an electrically heating wire wound on the temperature sensor to other two before formation of a plurality of catalyst layers on the enclosure. CONSTITUTION:A temperature sensor 3 comprises a heat resistant and insulating case 3a and a heat sensitive body 4. Catalyst layers 6a-6d are formed overlapped according to the type of gas to be detected on the enclosure of an electrically heating wire 5 wound on the surface. The catalyst layers 6a-6d have particles of catalysts connecting together in point contact to maintain the breathing property better. The inner side of an airtight terminal 1 is inserted into gas to be detected and current flows through an electrically heating wire 5 from lead wires 2c and 2d to heat activating the reaction of the catalyst layer 6 while a resistance value measuring circuit to lead wires 2a and 2b to determine the resistance value of the heat sensitive body 4. Thus, temperature changes based on the reaction of the catalyst layer 6 can be measured according to the resistance value of the heat sensitive body 4 thereby enabling free detection of the presence, concentration or the like of the gas. |
