| 摘要 |
An exhaust purification device has a NOx catalyst that occludes NOx contained in exhaust gas at a lean air fuel ratio and that purifies (reduces) and discharges the occluded NOx at a rich air fuel ratio. The device performs full purge for discharging substantially an entirety of the occluded NOx at once based on establishment of an execution condition of the full purge to recover exhaust purification performance of the NOx catalyst. The device has a program for performing partial purge for discharging only part of the occluded NOx before the execution of the full purge. The device consecutively and repeatedly performs the partial purge except for the period in which the full purge is performed.
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