| 摘要 |
<p>Provided is a catalytic combustion type gas sensor in which the temperature and the electrical resistance of a catalyst metal are increased by combustion heat generated when a combustible gas burns upon contact with the catalyst metal that has been heated by voltage application, and in which the combustible gas present in a given or higher concentration is detected based on the increase in electrical resistance. In the sensor, a voltage is applied to the catalyst metal (detection element) so that the catalyst metal has a standby temperature, which is obtained by subtracting the temperature increase caused by combustion heat generated when the combustible gas present in a given concentration burns upon contact with the catalyst metal (detection element) from a desorption temperature at which an adsorbate that has been adsorbed onto the catalyst metal through silicon (Si) poisoning is desorbed. The desorption temperature is set to a temperature in the range of 350-600°C, excluding 350°C. When the sensor is switched on and/or switched off, a voltage is applied to the catalyst metal (detection element) so that the catalyst metal (detection element) is heated to a temperature in the range of 350-600°C. Thus, the catalytic combustion type gas sensor can be inhibited from deteriorating in detection sensitivity.</p> |
