| 摘要 |
Object: To hold the crank arm in a horizontal state. Solution: The bicycle driving device includes a shaft 3 rotatably mounted on a part of a body frame, two crank arms 6 perpendicularly disposed at both ends of the shaft 3 so as to be symmetrical with each other at 180° with respect to a center of the shaft 3 as a base point, a gear 8 mounted at one end of the shaft 3, which is provided with a chain, a fly wheel 5 with a predetermined mass, which is disposed parallel to the gear 8, and a balance weight 2 mounted on a disk plate 22 as a predetermined plane parallel to the gear 8 on an extension of a longitudinal center line of any one of the crank arms 6. Selected figure: Fig. 1 |
