| 摘要 |
PROBLEM TO BE SOLVED: To make it possible to accurately estimate a PM accumulation quantity of a filter for collecting the PM.SOLUTION: A single-tap filter 31 that collects PM (particulate matter) in exhaust gas of an engine 11 is constituted to have at least one cell an outlet side of which is opened out of remaining cells except for partial cells inlet sides of which are closed out of a plurality of cells. Since a predetermined correlation is held among a PM accumulation quantity of the single-tap filter 31, a PM quantity (sensor-detected PM quantity) detected by a PM sensor 32, and a PM collection rate of the single-tap filter 31, an ECU 30 estimates (calculates) the PM accumulation quantity on the basis of the sensor-detected PM quantity and the PM collection rate. At that time, in the light of a change in the PM collection rate in response to parameters such as the PM accumulation quantity, an exhaust gas flow rate, an exhaust gas pressure, an exhaust gas temperature, and an ash accumulation quantity, the PM collection rate used to estimate the PM accumulation quantity is changed in response to these parameters.SELECTED DRAWING: Figure 1 |
