| 摘要 |
PROBLEM TO BE SOLVED: To provide a variable valve gear for an internal combustion engine capable of compatibly achieving both of quick response in light and middle load operation of a vehicle and high output performance in heavy load operation of the vehicle. SOLUTION: In this variable valve gear, valve close timing change quantity per unit controlled variable of a control actuator selectively using cam profiles of a cam for an intake valve as a valve close characteristic changing means changing valve close characteristics in control to the low lift region S1 and valve close characteristics in control to the high lift region S2 according to demanded operation characteristics of a vehicle, and valve close timing change quantities C, D are set in a relation of C>D when valve close timing change quantity per unit controlled variable of the control actuator in change to the low lift region is defined as C and valve close timing change quantity per unit controlled variable of the control actuator in change to the high lift region is defined as D. By this structure, a valve is closed with valve close characteristics appropriate for the light and middle load operation in low lift, and the valve is closed with quick valve close characteristics appropriate for the heavy load operation in high lift. COPYRIGHT: (C)2011,JPO&INPIT
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