Strength analysis and tooth shape optimization for involute gear with a few teeth

As a result of the inadequate carrying capacity and poor meshing performance of gears with a few teeth, the reasonable and optimal choice of parameters is a key step in design. Aiming at this problem, the stress equation for gear pairs with a few teeth was derived and it is discovered that the main failure mode of gears with a few teeth is pitting on contacting surface. At the same time, the results of theoretic analysis were also verified by strength test. A new optimization method of parameters which aimed at minimizing the contact stress was presented based on equal bending fatigue life at the tooth root of pinion and gear. The equation was solved by the genetic algorithm and reasonable design parameters are obtained. Tooth contact analysis based on finite element method is carried out and the results demonstrated that the method presented was an effective way to enhance the carrying capacity and meshing performance of gear pair with a few teeth. The study in this article laid a solid foundation for the further promotion of gear transmission with a few teeth.