How does a 3-speed hub gear work? | Structure and function explained simply
Learn more about the design and function of a 3-speed hub gear in this video. The heart of the hub gear is a planetary gear. With the help of clutches, in first gear, the drive is via the ring gear, and the output is via the planetary gear carrier (web). In second gear, the so-called direct drive, the hub is driven directly via the pinion. In third gear, the drive is via the planetary gear carrier, and the output is via the ring gear. Shifting between the individual gears is achieved via a sliding clutch that engages the respective components. To ensure that the wheel continues to rotate even when the pedals are stationary, a total of two freewheels are implemented with the help of pawls (overrunning clutch).
00:00 Planetary gear
01:08 Overrunning clutch (freewheel) on the planetary gear carrier
02:26 Overrunning clutch (freewheel) on the ring gear
03:43 Sliding clutch
04:36 Gear shifting
05:50 First gear (input: ring gear, output: web)
07:14 Second gear (direct drive)
08:37 Third gear (input: web, output: ring gear)