| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an exhaust emission control device for an internal combustion engine capable of more surely purifying exhaust gas by reducing chances that catalyst is inactive although temperature of catalyst reaches active temperature. <P>SOLUTION: This device is provided with a plurality of catalysts 3, 4 provided in series in an exhaust gas passage 2 of the internal combustion engine 1, a determination means determining whether rear stage catalysts 4 which are catalysts of the plurality of the catalysts except catalyst 3 positioned in a uppermost stream of the exhaust gas passage are under active state or inactive state, and an increase quantity means 5 increasing quantity of material activating the rear stage catalyst 4 in exhaust gas flowing in the rear stage catalyst as compared with a case that the determination means determines that the catalysts are under active state when the determination means determines that the rear stage catalysts are under inactive state. The rear stage catalysts can be recovered from the inactive state to the active state for the increase quantity means 5 to increase quantity of the material activating the rear stage catalysts 4. <P>COPYRIGHT: (C)2005,JPO&NCIPI |
