| 摘要 |
PROBLEM TO BE SOLVED: To prevent damaging of a bell crank, and prevent the bell crank from having a thing applied to it or caught by it. SOLUTION: An internal hub 10 is provided with a hub shaft 21, a drive body 22, a cylindrical hub shell 23, a planetary gear mechanism 24, an operation mechanism 25, and a bell crank 26. The drive body is rotatably supported on the hub shaft 21, and connected to a small gear 32. The hub shell 23 has a containing space 23a inside, it is rotatable around the hub shaft 21, and it is connected to a rear wheel. The planetary gear mechanism 24 has plural power transmission passages, so power from the drive body 22 is transmitted through one selected passage among plural power transmitting passages to the hub shell 23. The operation mechanism 25 is composed to select one of the power transmitting passages by moving it in the hub shaft direction. The bell crank is composed to be installed on the hub shaft 23 on the inner side than the shaft end as it is installed on a frame, thereby the operation mechanism is moved in the shaft direction. |
