| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide an exhaust emission control device of an internal combustion engine capable of accurately calculating the degree of thermal degradation of an exhaust emission control part by considering the advancement of thermal degradation immediately after the stoppage of the internal combustion engine. <P>SOLUTION: By turning off an ignition switch, a thermal degradation advancement width dKinc after the stoppage of the internal combustion engine is calculated by using a map for thermal degradation advancement width dKinc after the stoppage of the internal combustion engine based on a catalyst temperature T and the degree K of thermal degradation calculated at present (S154). The calculated value is added to the degree K of thermal degradation to increase the degree K of thermal degradation (S156). Accordingly, an accurate degree K of thermal degradation of a catalyst in the exhaust emission control part can be provided in consideration of the advancement of thermal degradation immediately after the stoppage of the diesel engine. Furthermore, when the rotational speed NE of the engine is lower than an increase determination reference rotational speed NEk ("no" in S152), the degree K of thermal degradation is not excessively increased since an increase treatment for the degree K of thermal degradation is not performed, and even if the turning on/off of the ignition switch is repeated in a short time, accurate degree K of thermal degradation can be maintained. <P>COPYRIGHT: (C)2007,JPO&INPIT</p> |
