| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide an air-fuel ratio detecting device of an internal combustion engine, detecting an air-fuel ratio in a cylinder in all regions with high accuracy. <P>SOLUTION: The air-fuel ratio detecting device includes a cylinder pressure sensor. A combustion velocity is calculated from a detection value of the cylinder pressure sensor (120). A relationship between combustion velocities and air-fuel ratios in the cylinder is stored. The air-fuel ratio in the cylinder corresponding to the combustion velocity is acquired from the relationship. When there are a plurality of air-fuel ratios corresponding to the combustion velocity in the relationship, a target air-fuel ratio is varied (160). Based on a combination of plus or minus of a variation of combustion velocity after the target air-fuel ratio is varied and a direction in which the target air-fuel ratio is varied, a single air-fuel ratio is selected among the plurality of air-fuel ratios (180). <P>COPYRIGHT: (C)2011,JPO&INPIT</p> |
