摘要 |
PROBLEM TO BE SOLVED: To increase a valve timing control accuracy by accurately calculating a camshaft phase even in a low rotation area where a variation in rotation is increased in a system in which a valve timing is changed by changing the camshaft phase (rotating phase of a camshaft relative to a crankshaft) by a variable valve timing device. SOLUTION: An ECU 28 calculates the rotating speed of an engine for calculating the camshaft phase based on a time Tθrequired for the crankshaft to rotate by a sampling angleθand obtains the camshaft phase from a time difference in output timing between a crank angle signal and a cam angle signal by using the rotating speed of the engine. In this case, in the low rotation area where the variation in the rotation of the engine is large, the sampling angleθwhen the rotational speed of the engine for calculating the camshaft phase is calculated is reduced so that the rotational speed of the engine for calculating the camshaft phase and also the camshaft phase can be accurately calculated. COPYRIGHT: (C)2006,JPO&NCIPI
|