Dynamics And Load Sharing Of Planetary Gear With Meshing Beyond Pitch Point And Experimental Verification

In the process of gear meshing of planetary gear transmission system, a plurality of planets were used to bear the load simultaneously. Because of the advantages of large transmission ratio, strong load capacity and high transmission efficiency, planetary gear is widely used in various areas of transmission machinery, such as automobiles, wind engines, marine, aeronautics and astronautics and so on. In the gear system, when the actual line of action located beyond the pitch point, it is called gear with meshing beyond pitch point. This paper engaged in planetary gear system with meshing beyond pitch point(especially the planetary gear system with meshing behind pitch point for the internal-meshing pair), studies were as follows:A planetary gear translational-rotational dynamics model with meshing beyond pitch point in consideration with flexbile ring was established, the meshing errors, relative displacements, meshing stiffness, damp and friction were analyzed. The motion differential equations were derived depend on newton’s laws of motion and then the solution of the equations was discussed.The equations were solved by using the ode45 Runge-Kutta method, inherent characteristics, dynamics and load sharing characteristics were obtained. Besides that, the impacts of coefficients of friction, flexible ring gear, coefficients of beyond pitch point and input conditions on dynamics load sharing characteristics were analyzed. Then the dynamics and load sharing characterics analysis software was developed by Matlab.The implementation of gear with meshing beyond pitch point was studied, geometric calculation formula of internal-meshing pair with non-equivalent modulus and non-equivalent pressure angle were derived to provide parameter foundation of the next experiment. Load sharing experiment principal of planetary gear system with meshing beyond pitch point was analyzed, the ranges and placement locations of strain gauges used in the experiment were also calculated by Ansys.The running and load sharing experiment program of planetary gear with meshing beyond pitch point was designed, the experiment platform was launched and at last the experiment was developed to verify the reliability of theoretical analysis before.