The tooth profile of the sprocket should allow the chain links to enter and retreat smoothly and freely.

The tooth shape of the sprocket should ensure that the chain links enter and exit the mesh smoothly and freely, and it is not easy to break off the chain, and the shape is simple and easy to process. GB/T1243-97 specifies the end face tooth profile (Table 9-3) and shaft surface tooth profile (Table 9-4) of the roller chain sprocket, because the roller surface tooth profile and the sprocket tooth profile are non-conjugated teeth Therefore, the sprocket tooth shape design has greater flexibility, that is, it can be used within the maximum and minimum ranges.If the sprocket adopts a standard tooth shape, the end face tooth shape may not be drawn on the working drawing of the sprocket, and only need to indicate that it is manufactured according to GB/T1243-97.However, in order to turn the blank, the tooth profile of the shaft surface needs to be drawn.