| 摘要 |
<p>PURPOSE:To shorten the length of a part projecting from the front end of a cylinder head by providing a timing adjusting motor in the front end of the cylinder head and freely rotatably engaging a driving cylinder driven by this timing adjusting motor with the tip of a cam shaft. CONSTITUTION:A speed reduction umbrella gear 19 engaged with the driving umbrella gear 18 of a timing adjusting motor 17 fixed in the tip of a cylinder head 11 via a bolt 16 and capable of rotating forward and backward is formed integrally with the base tip of a driving cylinder 14. The driving cylinder 14 is engaged with the tip of a cam shaft 12 freely rotatably held in the cylinder head 11 via a needle ball bearing so as to be relatively and freely rotated. Thus, the length of a part projecting from the front end of the cylinder head 11 can be shortened and the device can be made compact. Moreover, since no bending moment along an axial line works on a rotational part, driving power is smoothly transmitted, and the tip of a female screw cylinder and an intermediate cylinder are linked with each other via thrust receiving means and thus durability of parts can be improved.</p> |
