CONTROL DEVICE FOR INTERNAL COMBUSTION ENGINE

摘要

PROBLEM TO BE SOLVED: To prevent increase of NOxamount emitted into the atmosphere.

SOLUTION: A control device for an internal combustion engine comprises: a means for detecting a bed temperature of a lean NOxcatalyst 5; a means for detecting a NOxamount emitted from an engine (an engine emission NOxamount); a means for detecting NOxconcentration in exhaust emitted from the engine (engine emission NOxconcentration); a NOxemission amount calculating means for calculating a current NOxamount after passing through the lean NOxcatalyst (tail pipe NOxemission amount), based on the engine exhaust NOxamount and the engine emission NOxconcentration; a means for setting target values of the tail pipe NOxemission amounts (target NOxemission amounts) for each operating point based on each target value of the bed temperature, engine emission NOxamount, and NOxconcentration; and an operating point changing means. The operating point is changed to make the current tail pipe NOxemission amount smaller than the target NOxemission amount, by changing at least one of the bed temperature, engine emission NOxamount, and NOxconcentration is changed.

COPYRIGHT: (C)2008,JPO&INPIT