| 摘要 |
<p>PROBLEM TO BE SOLVED: To properly estimate an amount of NOx in an exhaust gas without using a NOx sensor.SOLUTION: An exhaust emission control device of an internal combustion engine E related to the present invention includes a filter 11 for collecting fine particles in exhaust, and a control device 100 estimating a NOx amount in an exhaust gas flowing into the filter. The control device calculates an amount of first fine particles removed from the filter when a filter temperature is in a prescribed first temperature range, and estimates the NOx amount on the basis of the amount of first fine particles. The control device calculates the amount of first fine particles, and further calculates an amount of second fine particles removed from the filter by prescribed filter regeneration control, among the amount of first fine particles, and estimates the NOx amount on the basis of the amount of first particles and the amount of second fine particles, when the filter temperature is in a second temperature range higher than the first temperature range.</p> |
