| 摘要 |
A gas sensor is provided in which a gas detection element (8,9) is mounted on a wiring substrate. A protective cap (3) having gas inlets (31 to 39) formed therein is attached to the wiring substrate. The gas sensor has a structure capable of effectively preventing emanation of gas from the wiring substrate (2) and the protective cap. The sensor effectively prevents a gas from emanating from the wiring substrate (2) and the protective cap (3). The wiring substrate where a plurality of gas detecting elements(8,9) are to be mounted is formed of a ceramic wiring substrate(2) which is excellent in heat resistance. The protective cap (3) having gas inlets or air vents(31 to 39) is formed of a metal which is excellent in heat resistance. The metal protective cap (3) is fitted to the ceramic wiring board (2) instead of using adhesive. In this way a gas sensor (1) is manufactured. Adoption of such a structure enables suppression of the gas emission from the ceramic wiring board(2) and the metal protective cap(3) effectively during the manufacturing step or in use of the gas sensor(1) attached to a car, thereby preventing lowering of the gas detection accuracy or early deterioration of the gas detecting elements(8,9) |
