Patent ID: 6973778

Claim:
A regeneration device for a diesel particulate filter which traps particulate matter contained in an exhaust gas of a diesel engine, comprising: a mechanism which raises a temperature of the exhaust gas in order to burn the particulate matter trapped in the filter, the mechanism being configured to raise the temperature of the exhaust gas to a higher temperature as an amount of particulate matter trapped in the filter decreases; a sensor which detects the amount of particulate matter trapped in the filter; a sensor which detects a temperature of the filter; and a programmable controller programmed to: set a target exhaust gas temperature such that the target exhaust gas temperature is increased as the amount of the particulate matter trapped in the filter decreases; control the mechanism to raise the exhaust gas temperature to the target exhaust gas temperature; cumulatively calculate a time during which the temperature of the filter exceeds a target temperature; determine, when the temperature of the filter does not exceed the target temperature, whether or not the temperature of the filter exceeds a temperature allowing combustion of the particulate matter, which is lower than the target temperature, and calculate an effective regeneration time by multiplying a time during which the temperature of the filter exceeds the temperature allowing combustion of the particulate matter by a predetermined coefficient, combined with the time during which the filter temperature exceeds the target temperature, as an effective regeneration time; and estimate an amount of burned particulate matter in the filter based on the effective regeneration time.