Patent ID: 8733081

Claim:
A control apparatus for an internal combustion engine comprising: an internal combustion engine including at least one recirculating gas generating cylinder capable of recirculating a part of its exhaust gas to an intake system and at least one recirculating gas nongenerating cylinder that does not recirculate its exhaust gas to the intake system; an exhaust gas recirculating path having one end connected to an exhaust path through which exhaust gas only from the recirculating gas generating cylinder flows and having the other end connected to the intake system; an exhaust catalyst for purifying exhaust gas provided on an exhaust path through which exhaust gas from the recirculating gas generating cylinder and the recirculating gas nongenerating cylinder flows; a recirculating catalyst provided on the exhaust gas recirculating path for purifying exhaust gas that recirculates to the intake system; fuel cut means that executes fuel cut for temporarily stopping fuel injection of the internal combustion engine; and rich control means that performs rich control for controlling an air-fuel ratio of the internal combustion engine to be temporarily richer than a theoretical air-fuel ratio when the fuel injection is restarted after return from the fuel cut, wherein the rich control means includes air-fuel ratio control means that controls an air-fuel ratio in the recirculating gas generating cylinder to be richer than an air-fuel ratio in the recirculating gas nongenerating cylinder when the rich control and an exhaust gas recirculation by the exhaust gas recirculating path are simultaneously performed.