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 efficiently improves fuel consumption by optimizing the amount of fuel supply during forced regeneration.SOLUTION: An exhaust purification device for an internal combustion engine comprises: a filter 16 which is provided in an exhaust passage 13 of the internal combustion engine 10 and collects particulate substances in exhaust gas; capacitance detection units 17a, 17b and 21 which detect capacitance of the filter 16; and filter regeneration units 13 and 22 which can execute forced regeneration to burn and remove the particulate substances accumulated on the filter 16 by supplying fuel thereto. The filter regeneration units 13 and 22 stop fuel supply during execution of forced regeneration when detecting that a reduction rate of the capacitance per predetermined time has dropped below a predetermined lower limit threshold indicating a reduction in combustion efficiency of particulate substances.