Starting from the error excitation of transmission in the direction of meshing line, taking the mechanical gearbox as the object, the dynamic characteristics under the error excitation of transmission and the methods of vibration reduction and noise reduction for gear modification are studied

(1) The dynamic simulation model of the mechanical gearbox is established, the modal flexibility of the second gear under the excitation of the gear and the main reduction gear is analyzed, and the natural modal vibration mode is calculated; the dynamic response of the bearing force of the gearbox and the corresponding acceleration of the surface of the gearbox are obtained by the unit gear transmission error excitation;

(2) This paper expounds the principle of genetic algorithm, puts forward the process of algorithm compilation and optimization, and illustrates it with an example. Taking the transmission error as the optimization objective, the genetic algorithm is used to optimize the modification parameters of all gears, and the optimal modification scheme is obtained;

(3) The sensitivity analysis of gear modification to manufacturing error is analyzed, and the distribution of transmission error in manufacturing tolerance range before and after gear modification optimization is compared. The results show that after considering the manufacturing error, the optimal shape modification can obtain a higher stability of transmission error.