UNLESS.... the planetary gears are NOT actually fixed to the frame through the spindle, but their axes being rotated around a fixed sun gear. That is, the sun gear is fixed to the frame through the spindle, and around it the planetary gears rotate driven by the sprocket, and
each planetary gear rotates in the same direction as the sprocket, and drives the annulus and hence the hub in the same direction!!!!
OK, now I get it.
I think I answered my question.
Mods, feel free to lock this thread.
Originally Posted by
wroomwroomoops
PS: I do know that hub gears have their spindle fixed with the dropouts. I am guessing that the structure the spindle is connected with inside the hub, keeps the planetary gears in place, and the sprocket itself is driving a tubular part which, inside the hub, drives a sun gear.
This, however, still doesn't explain how the shell of the hub rotates in the same direction as the sun gear.