Patent ID: 7322185

Claim:
The front end blockage removal device for use with a regeneration device for a diesel particulate filter installed in an exhaust passage of a diesel engine, the filter having a front end facing upstream of the exhaust passage and trapping particulate matter in exhaust gas in the exhaust passage, the regeneration device regenerating the filter by burning the particulate matter trapped in the filter, the removal device comprising: a sensor which detects a pressure loss in the exhaust gas of the exhaust passage due to the filter; and a programmable controller programmed to; calculate a first particulate matter deposit amount of the filter based on the pressure loss; calculate an increase slope of the first particulate matter deposit amount; calculate a second particulate matter deposit amount of the filter based on a parameter other than the pressure loss; calculate an increase slope of the second particulate matter deposit amount; determine that a particulate matter blockage of the front end has occurred when the increase slope of the first particulate matter deposit amount is greater than the increase slope of the second particulate matter deposit amount, and the difference between the increase slope of the first particulate matter deposit amount and the increase slope of the second particulate matter deposit amount is equal to or greater than a predetermined determination value related to the increase slope; and control the regeneration device to regenerate the filter when the particulate matter blockage of the front end has occurred.