| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an exhaust emission control device for an internal combustion engine, capable of preventing the breakage of an exhaust postprocessing device by preventing an excessive temperature rise due to rapid combustion of HC adsorbed to the exhaust postprocessing device when the HC is supplied to raise the temperature of the exhaust postprocessing device. <P>SOLUTION: HC adsorption speed f per time adsorbed to an oxidation catalyst is obtained from a catalyst temperature T, an HC concentration HCpost, and last time HC total adsorbing amount HC'adsorb of the oxidation catalyst (maps a to c). On the other hand, purification reaction speed k (a map d) obtained from the catalyst temperature T is multiplied by the last time total adsorbing amount HC'adsorb, thereby obtaining HC purification speed per time purified from the oxidation catalyst, A value obtained by multiplying a deviation between the HC adsorption speed f and the HC purification speed by predetermined time Δt is added to the last time total adsorbing amount HC'adsorb, thereby obtaining present HC total adsorbing amount HCadsorb. When the HC total adsorbing amount HCadsorb exceeds a permissible amount HCmax, post injection of forced regenerating control is stopped. <P>COPYRIGHT: (C)2004,JPO |
