DETERIORATION DETECTING METHOD OF EXHAUST EMISSION CONTROL CATALYST

摘要

PROBLEM TO BE SOLVED: To provide a deterioration detecting method of an exhaust emission control catalyst capable of accurately detecting a deterioration degree of the catalyst by using one oxygen sensor.;SOLUTION: This deterioration detecting method of the exhaust emission control catalyst is characterized by detecting a change rate of sensor output to elapsed time in a stoichiometric vicinal area including a stoichiometric point, by acquiring a response waveform of the sensor output to a change in the air-fuel ratio, by continuously introducing exhaust gas when forcibly changing the air-fuel ratio of an air-fuel mixture so as to pass through a stoichiometric area, to the detecting electrode side of the oxygen sensor via a catalyst layer of the exhaust emission control catalyst or a catalyst material of the same component as this catalyst layer, by using the one oxygen sensor having a detecting electrode in contact with exhaust gas arranged by sandwiching a solid electrolyte and a reference electrode in contact with reference gas.;COPYRIGHT: (C)2010,JPO&INPIT