Patent ID: 6976483
Filing Date: 2005-12-20
Classification: F02D

Abstract:
1. An air-fuel ratio control apparatus for an internal combustion engine, comprising: a fuel injector injecting fuel to said internal combustion engine; an operating condition detector detecting operating conditions of said internal combustion engine; a concentration detector detecting the concentration of a specific component in an exhaust gas of said internal combustion engine; a heating device heating said concentration detector; and a control unit that receives detection signals from said operating condition detector and said concentration detector, to feedback control manipulated variable to be added to said fuel injector based on the detection signal from said concentration detector, and also to calculate manipulated variable to be added to said heating device, based on the detection signal from said operating condition detector, wherein said control unit; variably sets the manipulated variable of said heating device according to said operating conditions, and also switches a gain for said feedback control according to the manipulated variable of said heating device.