Patent ID: 6516759
Filing Date: 2003-02-11
Classification: F01L

Abstract:
A valve timing control apparatus for an internal combustion engine comprising:an intake valve and an exhaust valve driven to operate in synchronization with rotation of the engine; an engine operating condition detecting section for detecting operating conditions of the engine; a valve timing calculating section for calculating a target valve timing for at least one of said intake valve and said exhaust valve in accordance with the engine operating conditions; a variable valve timing mechanism for varying an opening timing and a closing timing of at least one of said intake valve and said exhaust valve; a valve timing detecting section for detecting an actual valve timing of at least one of said intake valve and said exhaust valve; a control value calculating section for calculating a control value based on said target valve timing, said actual valve timing and said engine operating conditions; an actual valve timing control section for outputting said control value as an output control value to said variable valve timing mechanism; wherein only when said target valve timing is within a prescribed control range, said control value, which corresponds to a deviation between said target valve timing and said actual valve timing calculated by said control value calculating section, is output as said output control value to said actual valve timing control section; and wherein when said target valve timing is outside said control range on a side where said control value is set to a large value, said output control value is made equal to the sum of a holding control value and a predetermined value.