Multi-speed sprocket assembly of a bicycle

摘要

A multi-speed sprocket assembly of a bicycle includes at least a small sprocket and a large sprocket which enable the chain to engage with different sprockets to attain the chain shifting effect by the guidance of the rear derailleur device. The improvement of the multi- speed sprocket assembly includes three feature teeth being furnished at both the large sprocket and the small sprocket wherein a side recess is formed on each of the feature teeth at the surface of a sprocket facing another sprocket, in addition, at the first and second feature teeth of the small sprocket, there is a circular top end recess extended from the top of the teeth at the surface subjected to forces and penetrated through the circular top end recess of the whole teeth. By means of the action of the three feature teeth and their recesses of the large and small sprockets, it can guide the direction of the sidetracking of the chain to carry out the chain shifting action and avoid the occurrence of interference phenomena, thereby, enable the chain to smoothly and steadily complete the chain shifting action without lifting up the chain.