EXHAUST EMISSION CONTROL DEVICE OF INTERNAL COMBUSTION ENGINE

摘要

PROBLEM TO BE SOLVED: To accurately obtain an amount of sulfur stored in an NOXabsorbent.

SOLUTION: An exhaust emission control device of an internal combustion engine includes the NOXabsorbent in an engine exhaust passage. The exhaust emission control device detects input NOXconcentration based on an engine operating state, detects an exit NOXconcentration by an NOXsensor disposed downstream of the NOXabsorbent, and calculates the NOXpurification rate EFF of the NOXabsorbent from these input NOXconcentration and exit NOXconcentration. The exhaust emission control device calculates a plurality of times the NOXpurification rate EFF separately at a time interval, and decides a linear expression m representing a relation between a fuel consumption rate QF and the NOXpurification rate EFF. When judged to have to conduct an SOXtreatment for reducing a stored SOXrate in the NOXabsorbent, the NOXpurification rate EFF at this time is calculated by using the linear expression m. The relation between the NOXpurification rate EFF and the stored SOXrate is previously obtained, and the stored SOX rate is calculated from the calculated NOXpurification rate EFF by using the linear expression.

COPYRIGHT: (C)2005,JPO&NCIPI