| 摘要 |
<p>PURPOSE:To obviate the need for corrective operation of a crank shaft, and cope with a high load applied to a gear part of a cam gear part by forming a shaft part, cam parts, and the cam gear part of a valve-cam shaft body by one piece synthetic resin, and forming a recessed part on the end face on the opposite side from the cam parts of the cam gear part to accomodate a centrifugal weight and a decomp. spring. CONSTITUTION:A valve-cam shaft body 23 is made of one piece synthetic resin, and is formed integrally by a shaft part 1, cam parts 2, 25, and a cam gear part 3. A circular ring-shaped recessed part 6 is formed on the end face 5 on the opposite side from the camm parts opposite the end face 4 on the cam parts side out of both the end faces 4, 5 of the cam gear part 3 in order to accomodate a decomp. centrifugal weight 8 pivoted to a pivoting shaft 7 so that it can freely oscillate, and a decomp. spring 11 provided between an oscillating end part 9 and a spring locking part 10. Thus, interference of a crank shaft with a counterweight is prevented to obviate the need for corrective operation of the crank shaft. Further, since the width of the gear part 19 of the cam gear part 3 can be kept wide, the cam gear part can be used for an engine, in which a high load is applied to the gear part 19.</p> |
