In the meshing process of gear hobbing, the gear hobbing hob is equivalent to the worm, so its stress condition is similar to that of the worm. Without considering the friction, the force FN focuses on the node P, which acts on the normal section (as shown in the figure). FN can be decomposed into three mutually straight components, namely, circumferential force ft, radial force FR and axial force F α 。 When the influence of friction is not considered, each component force is:
Where:
t1 – nominal torque acting on gear hob;
d1 — pitch circle diameter of gear hobbing hob;
αn — normal pressure angle.