| 摘要 |
PROBLEM TO BE SOLVED: To switch valve element lift amounts in a plurality of stages, by using a single valve drive path. SOLUTION: An intake valve 12 opens/closes an intake port 9 formed in a cylinder head 3 opened to a combustion chamber 8. A rocker arm 18 has an operation part 26 on which a push rod 15 driven by a valve cam is abutted, and a valve drive part 27 driving the intake valve 12. The rocker arm 18 is oscillatably attached by means of a supporting point change cam 33 attached to a drive shaft 31 rotatably mounted to the cylinder head 3. The supporting point change cam 33 has a plurality of oscillating centers. When the drive shaft 31 rotates the supporting point change cam 33, positions of the oscillating centers of the rocker arm 18 are changed and valve lift of the intake valve 12 is changed. COPYRIGHT: (C)2004,JPO&NCIPI
|
