Based on the meshing principle of equal height spiral bevel gear, the pitch cone and the base cone are two common vertices. For the cone with equal cone distance at the large end but different cone angles, the two cones intersect the same spherical involute to obtain the pitch circle and the base circle respectively.
In order to ensure that the full tooth height is equal everywhere, two cones with the same cone angle and the same axis as the pitch cone are constructed as the tooth top cone and tooth root cone. The two cones intersect the spherical involute to obtain the tooth top circle and tooth root circle respectively.
The radii of the big end base circle, pitch circle, tooth tip circle and tooth root circle are obtained by using the known conditions（ γ b 、 γ d 、 γα 、 γ f) And the distance from the big end base circle, pitch circle, tooth top circle and tooth root circle to the pitch cone top, that is, the cone height (Hb, HD, H) α 、 HF), and then get the parameters of the small end according to the tooth width（ γ b1 、 γ d1 、 γα 1 、 γ f1 、hb1 、hd1 、h α 1 、hf1 ） 。