Bicycle driving assistance device

摘要

A bicycle driving assistance device includes a crank having two pedals and a first chainwheel unit is connected to the crank and a gear box which has its input shaft connected to a first chainwheel unit. A one-direction bearing is connected to the input shaft so as to rotate in the direction to store energy. A vortex spring is connected between the input shaft and the case to which a first gear of the gear box is connected. An output shaft of the gear box outputs the energy to the rear chainwheel unit via the second chainwheel unit to move the rear wheel of the bicycle. The rear chainwheel unit and the crank are separated by a one-direction bearing. When the force applied to the pedals is less than the energy stored in the vortex spring, the energy is released to assist the rider to move the bicycle.