| 摘要 |
The invention is directed to an exhaust gas purification device for an internal combustion engine. An amount of fuel supply during a forced regeneration is optimized, and a fuel efficiency is effectively improved. The exhaust gas purification device includes a filter (16) provided in an exhaust passage (12) of the internal combustion engine (10) for collecting particulate matter in an exhaust gas, an electrostatic capacity detecting unit (17a, 17b, 21) that detects an electrostatic capacity of the filter (16), and a filter regenerating unit (13, 22) that supplies fuel to the filter (16) and executes a forced regeneration to burn and remove particulate matter that has accumulated in the filter (16). The filter regenerating unit (13, 22) stops supplying fuel when a rate of decrease in the detected electrostatic capacity per predetermined period of time reaches or falls below a predetermined lower threshold, which indicates a drop in burning efficiency of the particulate matter, while the forced regeneration is being executed. |
