| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an exhaust emission control device quickly raising temperature of an exhaust emission control catalyst in exhaust emission control devices for internal combustion engines having a HC adsorption catalyst disposed in an exhaust gas passage on an upstream side of the emission control catalyst. <P>SOLUTION: This exhaust emission control device executes an adsorption process for adsorbing hydrocarbon in exhaust gas to the HC adsorption catalyst at first in an engine cold start, executes a bypass process for making the exhaust gas bypass the HC adsorption catalyst and flow in the exhaust emission control catalyst, and next executes a temperature raise process for raising temperature of the exhaust emission control catalyst by making hydrocarbon adsorbed to the HC adsorption catalyst discharged and supplying the same to the exhaust emission control catalyst. Hydrocarbon of first target quantity is adsorbed to the HC adsorption catalyst before executing the temperature raise process in the present engine cold start. The process is changed over from the bypass process to the temperature raise process after temperature of the exhaust emission control catalyst exceeds the temperature at which hydrocarbon starts oxidation during the bypass process. <P>COPYRIGHT: (C)2009,JPO&INPIT |
