The linear part of the side edge of gear hobbing hob mainly completes the generation of gear tooth profile, but there are inevitable errors in the manufacturing of gear hobbing hob, which will produce the original tooth profile angle error of gear hobbing hob. When the gear crown angle changes, as shown in Fig. 1 and Fig. 2.
If the straightness of the side edge of the gear hobbing hob is good, the relationship between the tooth profile error of the gear hobbing hob and the tooth profile angle error is as follows:
Of which:
α —— Ideal tooth profile angle of gear hobbing hob;
∆ J – profile error of side edge of gear hobbing hob.
Since ∆ J is the tooth profile error of gear hobbing and hobbing, the error between any point of the side edge and the theoretical tooth profile can be considered to be − ∆ J / 2 ~ ∆ J / 2.