An analytical study of the effect of the contact ratio on the spur gear dynamic response

A model was used, where the total gear mesh stiffness was approximated by t wo constant stiffness levels, in order To analyze the influence of the cont act ratio on the dynamic response of spur gears. Due to the stiffness varia tion there is parametric excitation of the transmission error, which genera lly causes tooth separation at certain critical relational speeds. The pres ent paper discloses a method to analytically calculate which contact ratio to use in order to avoid tooth separation near a specific critical rotation al speed.