Patent ID: 7159550

Claim:
A variable valve train an internal combustion engine, comprising: a camshaft provided for rotation in the internal combustion engine; a rocker shaft provided in the internal combustion engine; and a rocker arm mechanism which is driven by a cam formed on the camshaft and opens and closes an intake or exhaust valve, wherein the rocker arm mechanism comprises: a first arm rockably supported on the rocker shaft and configured to drive the intake or exhaust valve; a second arm which is driven by the cam and rocks around a pivot on the side of the rocker shaft; a third arm which is rockably provided on a support shaft located near the rocker shaft and is configured to be displaced to drive the first arm as the second arm rocks; and a variable mechanism which displaces the pivot for the second arm on the side of the rocker shaft, wherein the third arm has a transmission surface portion which is displaced as the second arm rocks and touches the first arm to drive the first arm, and the transmission surface portion is provided with a conversion portion at which the distance from the center of the support shaft to the transmission surface portion changes so that the rocking amount of the second arm is converted to drive the first arm.