| 摘要 |
<P>PROBLEM TO BE SOLVED: To increase the assurance distance of emission in an exhaust emission control device having a NOx storage-reduction type catalyst for storing NOx contained in the emission from an internal combustion engine. <P>SOLUTION: The S poisoning recovery control at the normal target temperature taking into consideration the thermal degradation of a NOx storage-reduction type catalyst is performed for every predetermined period (every time when the integrated S poisoning amount reaches the predetermined value), and the S poisoning recovery control with the control target temperature being higher than the normal target temperature is performed at every interval longer than that for the normal control to temporarily enhance the SOx emission property. Thus, not by setting the control target temperature during the S poisoning recovery control to be constantly high, but by setting it intermittently higher at every predetermined period, the SOx emission property after traveling a long distance can be ensured while suppressing the thermal degradation of the NOx storage-reduction type catalyst, and degradation of the emission after traveling a long distance can be prevented. <P>COPYRIGHT: (C)2009,JPO&INPIT |
