| 摘要 |
PROBLEM TO BE SOLVED: To lower a height of lift portions of end face cams of both end faces of a cam element portion while surely switching (shift between a first prescribed position and a second prescribed position) of a valve opening/closing cam portion of the cam element portion.SOLUTION: First and second detent mechanisms 45, 46 are constituted so that when a cam element portion is shifted to one side in a cam axial direction from a second prescribed position, a second pressing member 43b is moving on a second apex portion 56 when a first pressing member 43a gets over a first apex portion 55, and the shift to one side of the cam element portion can be assisted by pressing an inclined portion 51a of a first groove 51 by the first pressing member 43a, and when the cam element portion is shifted to the other side in the cam axial direction from the first prescribed position, the first pressing member 43a is moving on the first apex portion 55 when the second pressing member 43b gets over the second apex portion 56, and the shift to the other side of the cam element portion can be assisted by pressing an inclined portion 53a of a third groove 53 by the second pressing member 43b. |
