Variable valve drive mechanism and intake air amount control apparatus of internal combustion engine

摘要

A variable valve drive mechanism of an internal combustion engine is provided which includes a camshaft that is operatively connected to a crankshaft of the engine such that the camshaft is rotated by the crankshaft, a rotating cam provided on the camshaft, and an intermediate drive mechanism disposed between the camshaft and an intake or exhaust valve of the engine. The intermediate drive mechanism is supported rockably on a shaft that is different from the camshaft, and includes an input portion operable to be driven by the rotating cam of the camshaft, and an output portion operable to drive the valve when the input portion is driven by the rotating cam. The variable valve drive mechanism further includes an intermediate phase-difference varying device for varying a relative phase difference between the input portion and the output portion of the intermediate drive mechanism.