How does a 3-speed internal-gear hub work? | design and operation simply explained

Find out more about the structure and function of a 3-speed gear hub in this video. The heart of the gear hub is a planetary gearbox. With the help of clutches, the drive in first gear is via the ring gear and the output via the carrier of the planetary gearbox. In second gear, the so-called direct drive, the hub is driven directly by the sprocket. In third gear, the drive is provided by the carrier and the output by the ring gear. The individual gears are shifted using a sliding clutch, which engages with the respective components. To ensure that the wheel can continue to rotate even whnen the pedals are stationary, two overrunning clutches are realized using ratchets.

00:00 Planetary gear
01:03 Overrunning clutch on the carrier (freewheel)
02:09 Overrunning clutch on the ring gear (freewheel)
03:22 Sliding clutch
04:09 Shifting gears
05:23 First gear (input: ring gear, output: carrier)
06:38 Second gear
07:39 Third gear(input: carrier, output: ring gear)