| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an exhaust emission control device for an internal combustion engine suppressing degradation in exhaust cleaning performance of NO<SB>x</SB>absorbent or a particulate filter, when an engine load or its change rate gets small. <P>SOLUTION: A first exhaust passage 22a and a second exhaust passage 22b are branched from an exhaust passage 21 of the internal combustion engine, a first exhaust control valve 26a and the NO<SB>x</SB>absorbent are disposed in the exhaust passage 22a, and a second exhaust control valve 26b and the NO<SB>x</SB>absorbent are disposed in the exhaust passage 22b. When the engine load or its change rate gets smaller than a preset value, opening of the first exhaust control valve 26a and the second exhaust control valve 26b is changed to be intermediate opening, so as to suppress decrease in temperature of the NO<SB>x</SB>absorbent 67 disposed in the first exhaust passage 22a and the second exhaust passage 22b. <P>COPYRIGHT: (C)2008,JPO&INPIT |
