Patent ID: 7181909

Claim:
A control method for an exhaust gas purification system, in an internal combustion engine mounted on a vehicle provided with a diesel particulate filter device in the exhaust passage thereof, having a diesel particulate filter control means including: a collecting area detection means in which the collecting quantity area where the quantity of the collected matters collected in the filter of said diesel particulate filter device belongs to is detected from within a plurality of collecting quantity areas which are sectionalized depending on the quantity of collected matters; a travel distance area detection means in which the travel distance area where the travel distance belongs to is detected from within a plurality of travel distance areas which are sectionalized depending on the travel distance; a regeneration timing judgment means for judging the regeneration timing of the filter; and a forced regeneration control means for performing the forced regeneration of the filter by raising the exhaust gas temperature, wherein said diesel particulate filter control means actuates the forced regeneration control means when it is judged to be in a regeneration timing by the regeneration timing judgment means, when the forced regeneration is restarted after interrupting the forced regeneration by the forced regeneration control means, and in at least any one of cases where the collecting quantity area detected by the collecting quantity area detection means is in another collecting quantity area having a collecting quantity larger than that of the collecting quantity area immediately after interruption, or where the travel distance area detected by the travel distance area detection means is another travel distance area, having a travel distance larger than that of the travel distance area immediately after interruption, the forced regeneration is performed from the start, and in other case, the forced regeneration is performed for the remained period of time of the previous forced regeneration, continuing to the previous forced regeneration.