| 摘要 |
PURPOSE: A crank arm assembly for a bicycle is provided to improve the driving force of a bicycle by increasing and delivering the power of a pedal using a lever principle. CONSTITUTION: A hub body(106) is projected shorter than the length between the center of a shaft(102) and a driving chain gear(101), increases power transmitted from a pedal(104) using a lever principle, and delivers the power to the shaft. A crank arm(105) comprises a joint part, a pressure increasing part(108), and a compressing part(109). The joint part is coupled with the hub body. The pressure increasing part is connected to the end of the joint part in arc or spiral shape and transmits the power of the pedal to an arm hub(103). The compressing part is connected to the end of the pressure increasing part and has the pedal on the end. |
