| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide technology enabling to suitably inhibit deterioration of exhaust emission by stably supplying oxygen to an exhaust passage between a storage reduction type NOx catalyst and an auxiliary catalyst in an exhaust emission control device for an internal combustion engine. <P>SOLUTION: This device is provided with the storage reduction type NOx catalyst 10 arranged in an exhaust pipe 7c of the internal combustion engine 1, the auxiliary catalyst 11 arranged in the exhaust pipe 7c of a downstream of the NOx catalyst 10 and having oxidation capacity, a reducer adding valve 12 supplying fuel to exhaust gas in an upstream of the NOx catalyst 10, and a bypass passage 14 supplying exhaust gas which is exhaust gas in the upstream of the NOx catalyst 10 and contains fuel less than fuel contained in NOx catalyst flow in exhaust gas supplied with fuel by the reducer adding valve 12 and flowing in the NOx catalyst 10, to the exhaust pipe 7c between the NOx catalyst 10 and the auxiliary catalyst 11. <P>COPYRIGHT: (C)2008,JPO&INPIT |
