| 摘要 |
<p>An exhaust gas sensor comprises a first exhaust gas sensing element (46), composed, for example, of titania, responsive to temperature and to the partial pressure of oxygen, and a second similar metal oxide ceramic element (48) which also is responsive to exhaust gas sensor temperature, but is more slowly responsive to the partial pressure of oxygen in the exhaust gases. Changes in partial pressure of oxygen are detected by connecting the sensor elements (46,48) series with each other and with a source of electrical energy (60) and detecting the voltage change across one of the elements. Resistances (62,RB) connected in series with the second element and/or in parallel therewith act to inhibit the reduction in the magnitude of the change in voltage signal produced in the sensor circuitry which would otherwise result from prolonged exposure of the sensor ceramic elements to exhaust gases produced by combustion of a rich air/fuel mixture or a lean air/fuel mixture.</p> |
