| 摘要 |
<P>PROBLEM TO BE SOLVED: To effectively activate catalyst and convert not only HC and CO but also NOx. <P>SOLUTION: An exhaust passage 11 is branched off to a cold passage 61 and a warm passage 62. A catalyst 12 with NOx storage function is provided in the cold passage 61, and a warm conversion catalyst 63 excluding NOx storage material is provided in the warm passage 62. An active oxygen component forming device 20 discharging active oxygen component is provided in an upstream side of the catalyst 12 with NOx storage function in the exhaust passage 11. A device is provided with an operation control means 100 supplying active oxygen component during cold operation and stopping supply of active oxygen component during warm operation based on a detection value Tex of a temperature sensor SW3 detecting value relating temperature of exhaust gas. Moreover, the device is provided with an open close means 64 selectively opening and closing the cold passage 61 and the warm passage 62 controlling exhaust emission by the catalyst 12 with NOx storage function during cold operation and controlling exhaust emission by the warm conversion catalyst 63 during warm operation. <P>COPYRIGHT: (C)2008,JPO&INPIT |
