Valve timing control system for internal combustion engine

摘要

A valve timing control system includes a first device for changing a mounting angle between driving and driven rotators through relative rotation thereof and including first and second rotating mechanisms coupled to each other in series, and a second device for locking the first device at a mounting-angle position which is suitable for engine start and is set between a most-lagged-angle position and a most-advanced-angle position. The second device includes a first lock mechanism for locking the first rotating mechanism at one of the most-lagged-angle position and the most-advanced-angle position and a second lock mechanism for locking the second rotating mechanism at another position. The first and second rotating mechanisms are locked by the first and second lock mechanisms at opposite positions to maintain the mounting angle at the mounting-angle position suitable for engine start.