Patent ID: 7942123

Claim:
A variable valve system of an internal combustion engine, comprising: a drive shaft which has a drive cam on an outer periphery thereof and to which a power is transmitted from an engine crankshaft; a rockable cam which is rockably supported and opens/closes an engine valve; a transmission mechanism, one end side of which is rotatably linked to the drive cam through a pivot and the other end side of which is linked to the rockable cam, the transmission mechanism converting a torque of the drive cam into a rocking motion and transmitting the rocking motion to the rockable cam; a control shaft, a rotation of which is controlled by an actuator; and a control cam which is fixed on an outer periphery of the control shaft and is a rocking fulcrum of the transmission mechanism, a shaft center of the control cam deviating from a shaft center of the control shaft, and the variable valve system varying a valve lift amount of the engine valve by changing the rocking fulcrum of the transmission mechanism through a rotation control of the control cam via the control shaft, and the rocking fulcrum of the transmission mechanism during a small valve lift control of the engine valve being positioned in an area outside an arc locus which is drawn with the drive shaft being a center of the arc and passes through a rocking fulcrum position positioned at a time of a maximum valve lift and also inside an arc locus which is drawn with a pivot of the one end side of the transmission mechanism being a center of the arc and passes through the rocking fulcrum position positioned at the time of the maximum valve lift.