Tooth profile of sprockets
The tooth profile of the sprocket needs to ensure that the chain enters and exits the mesh smoothly and energy-savingly, minimizes the impact and contact stress of the chain link during meshing, and is easy to process.
The end face of the commonly used sprocket is composed of three arcs， which are aa, ab, cd and a straight line bc, referred to as three arc-straight tooth profile. The tooth profile is processed with standard tools and it is unnecessary to draw the end tooth profile on the sprocket working drawing, just indicate “tooth profile manufactured according to 3RGB1244-85” on the drawing would be fine.
The structure of sprockets
The sprockets with small diameter are generally made into an integrated type.
The medium-diameter sprockets are mostly made into a spoke plate type, and holes are made on the spoke plate for easy handling and clamping.
The sprockets with large-diameter can be made into a combined type, with the ring gear and the wheel core made of different materials, such as C45 or stainless steel.
The material of sprockets
The sufficient strength and wear resistance of the teeth should be ensured by the sprocket material. So the sprocket tooth surface is generally heat treated to make it reach a specific hardness.