| 摘要 |
A stepless transmission device for a bicycle which has sufficient durability and smooth operation characteristics for practical use is provided. The transmission device can steplessly change the rotational ratio of a wheel to a drive sprocket by changing the oscillation angle of rachet arms which are radially disposed on the periphery of a disk fixed to a shaft for said sprocket. The transmission device is characterized in that said rachet arms incorporated with respective crank arms are pivoted to said sprocket in positions equally distributed on a coaxial circle, and one end of each crank arm constitutes a guide pin, said guide pin being engaged in an annular groove which is coaxially provided in a rotatable bearing race the eccentricity of which can be changed. |
