| 摘要 |
<P>PROBLEM TO BE SOLVED: To enable early activation by arranging a bypass catalytic converter 18 on the further upstream side for performing exhaust emission control just after a cold start. <P>SOLUTION: An upstream side main passage 2 is connected with every cylinder 1, and mutual cylinders uncontinuous in an exhaust stroke are merged as an intermediate main passage 3, and finally become one downstream side main passage 7. A main catalytic converter 8 is interposed in the middle of the downstream side main passage 7. A selector valve 4 is interposed between the upstream side main passage 2 and the intermediate main passage 3. As a bypass flow passage, an upstream side bypass passage 11 branches off from the respective upstream side main passages 2, and the mutual adjacent cylinders are merged as an intermediate bypass passage 14, and finally become one downstream side bypass passage 16. The bypass catalytic converter 18 is interposed in the middle of a downstream side bypass passage 16. The bypass catalytic converter 18 is maximally arranged on the upstream side in the bypass flow passage. <P>COPYRIGHT: (C)2006,JPO&NCIPI |
