| 摘要 |
Disclosed is a gas sensor, particularly a lambda probe, for determining the oxygen concentration in the exhaust gas of an internal combustion engine that is operated using a fuel-air mixture. Said gas sensor comprises a pump cell with an outer electrode that is exposed to the exhaust gas, an inner electrode located in a measuring chamber which is separated from the exhaust gas by means of a first diffusion barrier, and an electronic circuit for generating a voltage applied between the outer electrode and the inner electrode as well as for measuring and evaluating a pump current that is generated in said process in order to draw a conclusion therefrom about the composition of the fuel-air mixture. The inventive gas sensor is characterized in that the outer electrode is arranged in an independent measuring volume which is separated by means of an additional, second diffusion barrier whose coefficient of diffusion is different from that of the first diffusion barrier while the circuit is configured so as to preferably repeatedly reverse the polarity of the voltage. |
