| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a controller of an internal combustion engine which controls emission of NH<SB POS="POST">3</SB>and NOx into the air. <P>SOLUTION: When, in a routine shown in Fig.4, a stoichiometric driving is requested, and an attained floor temperature of SCR 20 is estimated to be higher than a set temperature A, three air-fuel ratio controls are made according to the magnitude relation between an SCR occluded NH<SB POS="POST">3</SB>amount and an NSR occluded NOx amount. When (the SCR occluded NH<SB POS="POST">3</SB>amount)=(the NSR occluded NOx amount), an operation near the stoichiometry is executed over a predetermined time (Step 140). When (the SCR occluded NH<SB POS="POST">3</SB>amount)>(the NSR occluded NOx amount), a weak lean operation is executed (Step 160). When (the SCR occluded NH<SB POS="POST">3</SB>amount)<(the NSR occluded NOx amount), a rich spike is executed until an SCR generated NH<SB POS="POST">3</SB>amount exceeds the difference between the NSR occluded NOx amount and the SCR occluded NH<SB POS="POST">3</SB>amount (Step 180, 190). <P>COPYRIGHT: (C)2013,JPO&INPIT |
