A POWER DRIVEN DEVICE OF A BICYCLE

摘要

The device obtains a high multiplication ratio through a planet gear mounted between a crank shaft and a fly wheel. The device includes; planet gear (14) having carrier (1) of disk, pinions (4), ring gear (5) of housing (6) and central sun gear (7); carrier (1) formed with drive arm (2) and crank shaft (3); sun gear (7) integrally formed with fly wheel (8). The multiplying gear ratio shall be the number of teeth of the sun gear (7)/ (the number of the sun gear teeth + the number of ring gear (5)).