CONTROLLER FOR VARIABLE VALVE TIMING DEVICE

摘要

PROBLEM TO BE SOLVED: To reduce a stopper impact sound of a variable valve timing device caused by friction braking of an electromagnetic brake. SOLUTION: A stopper impact frequency is suppressed below a predetermined level by restricting a change rate of target rotation phase TGVTC by a target change rate set in such a way that it becomes smaller as the number of impact times of a stopper regulating a change amount of cam shaft rotation phase when increasing friction braking increases to reduce an impact sound and ensure long service life of the stopper.