Patent ID: 7114473

Claim:
A valve driving apparatus comprising: a three-dimensional cam of a three-dimensional map state, having uncountable cam profiles continuously ranged along a rotation axis direction; and a valve lifter following a cam surface of said three-dimensional cam, wherein a lift characteristic of a valve is continuously controlled by relative motions of said three-dimensional cam and said valve lifter, and wherein said three-dimensional cam has cam top portions formed to have a smoothly ranged edge line substantially along the rotation axis direction thereof, and a part of the edge line includes at least one valley portion to take on a row of mountains; wherein a cam peak portion of the cam top portion formng the valley portion is moderately set to be deviated toward a delayed side with reference to the rotation direction of said three-dimensional cam from the other cam peak portions of the edge line; and wherein one end side of said three-dimensional cam corresponds to a low engine rotation region, and the other end side corresponds to a high engine rotation region, and the cam top portion to be the valley portion of the edge line forms a continuous valley portion relative to the cam top portions on both sides along the direction of rotation axis, and also is set to be deflected at one end side of said three-dimensional cam.