In the process of gear transmission, in order to avoid jamming, clearance must be left between the sides of the teeth, at the same time, manufacturing error of the teeth and tooth surface wear will cause clearance between the gears.The influence of clearance is considered in the nonlinear time-invariant model and the constant meshing stiffness is used instead of the time-varying meshing stiffness.
Clearance function is a strong non-linear factor, which results in three different motion states of gear transmission system: impact-free state, unilateral impact state and bilateral impact state.
With the change of parameters, the gear transmission system will have jump of amplitude and various complex motion forms, such as subharmonic motion, quasi-periodic motion and chaotic motion.
Based on the research of non-linear time-varying model, domestic and foreign scholars focus on the knocking characteristics of gears, dynamic characteristics under the mixed action of random parameters and parameters, and the non-linear vibration form of gear transmission system under the fitted clearance function.
Because of the strong coupling between the clearance function and the time-varying meshing stiffness, the general clearance function and the time-varying meshing stiffness should be considered simultaneously in the dynamic model of gear transmission system.