Control device for internal combustion engine

摘要

A control device for an internal combustion engine, said control device implementing a lean control, whereby the air-fuel ratio of the exhaust gas flowing into an exhaust purification catalyst is set to a lean air-fuel ratio setting, and a rich control, whereby the air-fuel ratio of the exhaust gas flowing into the exhaust purification catalyst is set to a rich air-fuel ratio setting. When the amount of oxygen absorbed by the exhaust purification catalyst during lean control reaches or exceeds a criterion storage amount, a control is executed to switch to rich control. In addition, a control is executed to set the lean air-fuel ratio setting for a first intake air amount so as to be richer than the lean air-fuel ratio setting for a second intake air amount that is less than the first intake air amount.