| 摘要 |
<P>PROBLEM TO BE SOLVED: To optimally control the air-fuel ratio of an internal combustion engine using a catalyst having an Rh region carrying only Rh as a noble metal. <P>SOLUTION: The air-flow ratio of an engine 3 is controlled by detecting the outgas atmosphere by a second sensor 33 using a catalyst forming an oxidized region 22 on the downstream side of the Rh region. H<SB>2</SB>generated in the Rh region in the rich atmosphere is consumed in the oxidized region 22, thereby preventing a sudden change point of the second sensor 33 from being fluctuated. As a result, the time of the rich atmosphere is made longer to enhance NOx cleaning performance. <P>COPYRIGHT: (C)2006,JPO&NCIPI |
