| 摘要 |
A PM accumulation quantity estimation device, provided with an exhaust quantity computation means (51) for computing PM exhaust quantity which is discharged in an exhaust gas path (3), and a natural reuse quantity computation means (52) for computing a PM reuse quantity in a DPF (7) which is naturally reused, is configured to estimate the PM accumulation quantity in a PM accumulation quantity estimation means (50) in the DPF (7) from the difference between the PM exhaust quantity which is computed with the exhaust quantity computation means (51) and the PM reuse quantity which is computed with the natural reuse quantity computation means (52). The PM accumulation quantity estimation device is further configured such that, if a malfunction is found in an airflow meter (31), the PM reuse quantity from NO2 is computed, and the PM accumulation quantity in the DPF estimated, without using the airflow quantity which is measured with the airflow meter (31). |
