| Due to the complexity of planetary gear transmission system, the stresses produced by gear engagements have become the important factors influencing the bearing capacity and reliability. Therefore, in the design phase, to do some in-depth study of the dynamic mechanical properties of planetary gear transmission, with the aid of modern analytical software, is of great significance in improving the performance.In this dissertation, gear elastic contact mechanics model and finite element model are established based on Hertz contact theory, NGW modeled involute planetary gear transmission geometry model is established by using SolidWorks software, and the planetary gear transmission mechanism was assembled on the basis of gear accurate meshing, interference checking and movement simulation. In addition, with gear material added, gear contact pairs defined and boundary conditions and parameters set in ANSYS software, the grid control was used in meshing and the refined meshing control was applied in other key parts such as tooth surface, tooth roots and tooth crests in order to obtain higher precision and get close to the real working situation. The curves of dynamic stresses over time of the standard gear transmission were achieved, the reason and the relationship of the gears stress changes were analyzed, resulting that the maximum stress occurs within the planetary wheel meshing addendum due to the stress concentration phenomenon. The influence of tip stress concentration was reduced by addendum modification method, and the maximum stress occurs in the planetary wheel external gear tooth surface during single tooth meshing after modification, however, the gear contact ratio decreased and the maximum stress of the system increased slightly after the modification. Finally, by changing the gear modification coefficient, the maximum stress of the system was reduced, increasing the carrying capacity of the planetary gear mechanism. |
PDF Full Text Request