| 摘要 |
PROBLEM TO BE SOLVED: To provide an alcohol concentration estimating device for an engine, suitable for accurately estimating the alcohol concentration without deteriorating operating performance and a control device for the engine. SOLUTION: This alcohol concentration estimating device includes a fuel supply means for controlling a fuel injection amount so that an actual air-fuel ratio detected during retard combustion becomes a target air-fuel ratio and supplying the fuel to the engine 1 (S28-S31), an ignition timing control means for controlling the ignition timing so that during retard combustion, the engine rotational speed becomes a target rotational speed (S12-S15), and an alcohol concentration calculating means for calculating the alcohol concentration of fuel being used based on an ignition timing when the actual air-fuel ratio matches the target air-fuel ratio, and the engine rotational speed is stabilized and becomes the target rotational speed (S34). COPYRIGHT: (C)2010,JPO&INPIT |
