Patent attributes
A bicycle sprocket apparatus comprises a larger diameter sprocket and a smaller diameter sprocket, wherein the larger diameter sprocket has on its outer periphery a plurality of sprocket teeth, the smaller diameter sprocket has on its outer periphery a plurality of sprocket teeth, and a number of sprocket teeth on the smaller diameter sprocket is less than a number of sprocket teeth on the larger diameter sprocket. The larger diameter sprocket includes a tooth and a first chain receiving tooth disposed immediately behind the tooth in the driving rotation direction, wherein the tooth includes a control side surface and an inclined side surface. The control side surface is disposed on a leading side of the tooth facing the smaller diameter sprocket in the driving rotation direction, and it is shaped to inhibit movement of the chain towards the larger diameter sprocket so that the chain does not engage the first chain receiving tooth when the chain is shifted from the smaller diameter sprocket to the larger diameter sprocket. The first inclined side surface faces the smaller diameter sprocket, and it is inclined relative to a plane of the sprocket to follow a direction of movement of the chain when the chain is shifted from the smaller diameter sprocket to the larger diameter sprocket.