| 摘要 |
PROBLEM TO BE SOLVED: To provide a particulate accumulation amount estimating device capable of suppressing a variation in an estimate value of a particulate accumulation amount caused by a change in an ash accumulation amount in a filter.SOLUTION: In a particulate accumulation amount estimating device for detecting differential pressure at a front and rear of a DPF unit 33 by a differential pressure sensor, and determining, based on the detected differential pressure, whether a PM accumulation amount in the DPF unit reaches a regeneration request accumulation amount corresponding to a regeneration start time, a first detection value P' based on differential pressure detected by the differential pressure sensor 34 when, out of first and second regeneration performed at different times, the first regeneration performed earlier is finished is stored and held in a memory (step S20) until the second regeneration performed later is finished, and differential pressure Poxi corresponding to the regeneration request accumulation amount is corrected according to a difference value &Dgr;Poxi between a second detection value P based on differential pressure detected by the differential pressure sensor when the second regeneration is finished, and the first detection value P' stored in the memory (steps S19, S21). |
