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Technical problem

If the bicycle is to be moved without the use of the electric motor, for example because an energy storage device is exhausted or because the electric motor is switched off above a predetermined driving speed, the electric motor can be driven by the movement of the bicycle. A mechanical freewheel to decouple the electric motor from the wheel may not be possible on the hub motor. If the electric motor has permanent magnets, they can be twisted relative to an armature, inducing vortex currents that can cause a moment of delay. A braking effect can be felt and the operation of the bike without the electric drive can be unnecessarily difficult.

The solution

Enlarging the gap between the stator relative to the rotor. The solution is an adjustment

mechanism that can be easily integrated into the hub motor.



DE 10 2021 000 756 B4

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