EXHAUST PURIFICATION DEVICE FOR INTERNAL COMBUSTION ENGINE

摘要

PROBLEM TO BE SOLVED: To provide an exhaust purification device for an internal combustion engine which optimizes fuel supply amount during forced regeneration.SOLUTION: An exhaust purification device for an internal combustion engine comprises: a diesel particulate filter (DPF) 16 which collects PM; an exhaust temperature sensor 19 which detects an exhaust temperature; capacitance detection units 17a, 17b and 21 which detect capacitance of the DPF 16; an accumulation amount estimation section 22 which estimates a PM accumulation amount of the DPF 16 on the basis of the capacitance; and filter regeneration units 13 and 23 which can execute forced regeneration. The filter regeneration units 13 and 23 executes the forced regeneration when the exhaust temperature reaches a temperature threshold in a state where the PM accumulation amount reaches an accumulation amount threshold on the basis of the accumulation amount threshold smaller than an upper limit PM accumulation amount and the temperature threshold with which the accumulated PM can be burned and removed with a limited fuel supply amount.