Geared bicycle chain wheel - has one crank with internal toothed crown wheel and chain wheel with meshing pinion

摘要

The bicycle chain wheel is mounted on bearings independently from the cranks. The cranks are mounted on a shaft by roller bearings and the right hand crank has an internally toothed crown wheel. The chain wheel carrier has a pinion on a bearing on the right hand bearing. The right bearing is eccentric and supports the chain wheel carrier. As an example, the pinion can have 30 teeth and the crown wheel 45, giving 15mm eccentrically.