| 摘要 |
<p>PROBLEM TO BE SOLVED: To independently and accurately vary cam phases of an inner cam shaft and an outer cam shaft of a cam shaft having a double structure without coupling with each other.SOLUTION: An inner cam drive gear 19 engaged with an inner cam shaft portion 12 is fixed at an upper part of a center shaft 14, and an outer cam drive gear 18 engaged with an outer cam shaft portion 11 is supported under the inner cam drive gear 19. Under the outer cam drive gear 18, a second sleeve shaft 17 helical spline engaged with the outer cam drive gear 18 is inserted, and under the second sleeve shaft 17, a first sleeve shaft 16 straight spline engaged with the second sleeve shaft 17 is inserted. A lower part of the first sleeve shaft 16 is straight spline engaged with a crank driven gear 15 engaged with a crank shaft 1, and an intermediate part is helical spline engaged with a center shaft 14. The first sleeve shaft 16 and the second sleeve shaft 17 are made to individually slide, thereby varying cam phases of the inner cam shaft portion and the outer cam shaft portion.</p> |
