The bike chain drives a sun gear on the rear axle, which transmits power to planetary gears situated around it.
自行车的链条会驱动后轮轮轴上的太阳齿轮，将动力传送到四周的行星齿轮。
2
One or more of the hollow wheel gear, two or more planet gears, and sun gear comprise a plurality of teeth 4 that have been superfinished to a final surface roughness of 0.25 micron or less.
A planetary gearbox for a Marine propulsion unit or an earth moving unit, comprises a hollow wheel gear 1, two or more planet gears 2, and a sun gear 3.