Apparatus and method for controlling valve timing of engine

摘要

In an apparatus for variably controlling valve timing of engine by generating, between a crankshaft and a cam shaft, a phase difference which periodically varies in a manner synchronized with a rotational phase of the cam shaft: actual phase differences are obtained at two discrete rotational phases of the cam shaft, respectively; there is assumingly calculated an amount of deviation (phase deviation &thetas;) of phase difference relative to the rotational phase of the cam shaft; and the phase difference is feedback controlled based on that value of the detected phase difference which is corrected in accordance with the amount of deviation (phase deviation &thetas;).