| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a deterioration determination control device and a deterioration restoration control device for a NOx sensor for easily determining or diagnosing and restoring deterioration. <P>SOLUTION: The deterioration determination control device includes the NOx sensor 50 wherein each of a pump cell 240, a monitor cell 260 and a sensor cell 250 includes a pair of electrodes, and the pump cell and the monitor cell use respectively electrodes containing an Au material, and the sensor cell uses electrodes containing an Rh material; and a deterioration determination means for determining deterioration of the NOx sensor based on an output from the NOx sensor, when detecting for a prescribed time, a prescribed operation state under an atmosphere wherein the NOx concentration in exhaust gas is below a prescribed value, or NOx does not exist in the exhaust gas and the O<SB>2</SB>concentration is constant. The deterioration restoration control device includes a voltage application stopping means for stopping voltage application to the electrodes of the pump cell 240 for a prescribed time, when determined to be in the deteriorated state. <P>COPYRIGHT: (C)2010,JPO&INPIT |
