To decrease process charge

we can use the big CNC milling machine instead of the big sprocket making and finishing machine for machining a variety of and the small quantity-big sprocket.It is first digitized

and coordinates numerical calculation of radii and key-point

for example jumping-off and endpoint of arc and direct line and the center of circle etc.Then processing program is planed and it is processed.Digitalization and NC machining of big sprocket tooth profile is discussed.The key of tooth profile digitalization is the special method by which coordinate calculation of intersection of two-circle would be calculated

and it is difficult and taking time with the general math-method.It is convenient to program for numerical calculation with VB or C language.