The relation between the number of teeth, modulus, diameter of pitch circle, diameter of addendum circle and diameter of root circle of involute spur gear is explained
The relationship between the parameters of the standard spur gear is:D=mzM=p/ PI (P is tooth pitch)Da=d+2ha=d+2m (in formula, ha=m)Df=d-2hf=d-2.5m (in formula, hf=1.25m)
At design time, at least one of M and D should be computed, and then d (or m) and Z will be determined,
The number of teeth Z, modulus m, pitch diameter D, addendum circle diameter DA and root circle diameter df;
