Patent ID: 8904762
Filing Date: 2014-12-09
Classification: F01N,F02D

Abstract:
1. A control apparatus for an internal combustion engine comprising: a catalyst disposed in an exhaust passage of said engine; a downstream air-fuel ratio sensor disposed downstream of said catalyst in said exhaust passage; a target air-fuel ratio setting section configured so as to set, based on an output value of said downstream air-fuel ratio sensor, a target upstream air-fuel ratio which is a target value of an air-fuel ratio of a gas flowing into said catalyst to a target rich air-fuel ratio and a target lean air-fuel ratio, alternately; a fuel injection valve configured so as to inject a fuel to said engine; a fuel injection control section configured so as to determine a fuel injection amount which is an amount of said fuel injected from said fuel injection valve in accordance with said target upstream air-fuel ratio, and so as to have said fuel injection valve inject said fuel of said determined fuel injection amount; an evaporated fuel purge section configured so as to introduce an evaporated fuel generated in a fuel tank storing said fuel supplied to said fuel injection valve into an intake passage of said engine; and an evaporated fuel purge amount control section configured so as to control a purge amount which is an amount of said evaporated fuel introduced into said intake passage by said evaporated fuel purge section; wherein, said target air-fuel ratio setting section is configured: said evaporated fuel purge amount control section is configured so as to increase said purge amount as a magnitude of a difference between said target lean air-fuel ratio and said target rich air-fuel ratio becomes larger.