Patent ID: 6951195

Claim:
A variable valve mechanism of an internal combustion engine capable of changing at least one of a valve operation angle and a valve lift, comprising: a valve lift adjustment mechanism that adjusts the at least one of a valve operation angle and a valve lift with a higher precision in a region where the at least one of a valve operation angle and a valve lift is relatively small than in a region where the at least one of a valve operation angle and a valve lift is relatively large, wherein the valve operation angle is a region where the valve is opened, wherein the valve lift adjustment mechanism comprises: a control member; and a controller that adjusts the at least one of a valve operation angle and a valve lift by actuation of the control member, and that converts the actuation of the control member into a change in the at least one of a valve operation angle and a valve lift, and that achieves a smaller rate of conversion of an amount of actuation of the control member into an amount of change in the at least one of a valve operation angle and a valve lift in the region where the at least one of a valve operation angle and a valve lift is relatively small than in the region where the at least one of a valve operation angle and a valve lift is relatively large, wherein the controller comprises a cam provided on a camshaft that rotates in association with rotation of the internal combustion engine, and an intervening actuation mechanism having an input portion and an output portion which is pivotably supported by a shaft different from the camshaft and which actuates a valve via the output portion when the input portion is actuated by the cam, and wherein the control member is a control shaft whose amount of movement in a direction of an axis is associated with a relative phase difference between the input portion and the output portion of the intervening actuation mechanism, and wherein the controller adjusts the relative phase difference between the input portion and the output portion of the intervening actuation mechanism by moving the control shaft in the direction of the axis, and therefore adjusts the at least one of a valve operation angle and a valve lift.