To successfully vary valve lift amount by using oscillating actions while suitably suppressing change in the valve lift amount due to uneven wear of a cam, in a variable valve mechanism for an internal combustion engine.
The cam 58 having two oscillation cam faces comprising a zero lift face 58a and a pressing face 58b is provided in each cylinder. By oscillating the cam 58 by a motor 54A, the lift amount of a valve can be changed. At start of the oscillating action, one oscillation cam face to be used during the oscillating action is selected from the two oscillation cam faces. At this time, the one oscillation cam face as a control target is selected so that execution times (mode 1 action time, mode 2 action time) of the oscillating actions (oscillating action mode 1, oscillating action mode 2) of the respective two oscillation cam faces are set approximately equal to each other.
TSUJI KIMIHISA
SHU CHUCHI
Mamoru Takada
Hidekazu Onishi
Next Patent: EXHAUST SYSTEM MEMBER SUPPORTING STRUCTURE