| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide an exhaust emission control device capable of securely assuming an accumulated soot quantity and more precisely determining timing to carry out forced reactivation. SOLUTION: This exhaust emission control device is furnished with an oxidation catalyst, a pressure sensor to detect differential pressure before and after a particulate filter, a control part to determine whether to carry out the forced reactivation or not, etc. The control part computes a first assumed accumulated quantity of soot (a) in accordance with the engine speed and the differential pressure detected by the pressure sensor. Additionally, this control part computes a second assume accumulated quantity (b) in accordance with the engine speed and the fuel injection quantity. The second assumed accumulated quantity (b) is an integrated value until a current determination time point from a time point when the previous forced reactivation is finished. These first assumed accumulated quantity (a) and second assumed accumulated quantity (b) are compared with each other, and when at least one of them exceeds a set value, a temperature raising means to carry out the forced reactivation is actuated.</p> |
