The coordinate system shown in the figure is used for gear shaping of helical offset non orthogonal surface gears. Among them φ 2 = φ sNs /N2， φ 2、 φ S is the rotation angle of face gear and spiral gear shaper cutter respectively, N2 and ns are the number of teeth of face gear and spiral gear shaper cutter respectively; The coordinate systems S2 and SS are fixedly connected with the face gear and the spiral gear shaper cutter respectively; The auxiliary coordinate systems SG, SM, Sn and SP are fixedly connected with the frame; L0 represents the distance from the origin O2 of the face gear coordinate system to the origin OS of the spiral gear shaper coordinate system; E represents the offset distance of spiral gear shaper cutter; γ M is the staggered angle between the helical gear shaper cutter shaft and the face gear shaft.
