Patent ID: 7290511

Claim:
A valve train for an internal combustion engine, comprising: a valve operating cam rotating around a rotational center line in synchronism with a rotation of the engine; an engine valve including at least one of an inlet valve and an exhaust valve; a transmission mechanism for transmitting a valve drive force of the valve operating cam to the engine valve so as to operate the engine valve in opening and closing states, the transmission mechanism including: a primary oscillating member having an abutment portion which abuts with the valve operating cam, and oscillating about a primary oscillating center line by the valve operating cam; a secondary oscillating member having a valve abutment portion which abuts with the engine valve, transmitting the valve drive force via the primary oscillating member to the engine valve, and oscillating about a secondary oscillating center line; a holder supporting the primary and secondary oscillating members in an oscillatory fashion so that the primary and secondary oscillating center lines rotate together therewith, and oscillating about a holder oscillating center line which is different from the rotational center line of the valve operating cam; a drive mechanism for driving the holder so as to control valve properties including opening and closing timings and maximum lift amount of the engine valve in accordance with an oscillating position of the holder; wherein as the oscillating position of the holder approaches a predetermined position where a valve operating property where a maximum lift amount becomes maximum is obtained, a cam abutment position where a cam lobe portion of the valve operating cam and the cam abutment portion abut with each other approaches a specific straight line which passes through the holder oscillating center line and the rotational center line.