行星滚柱丝杠螺纹副-齿轮副同步啮合动态接触载荷特性

A numerical model of planetary roller screw is established by using the finite element method to reveal the dynamic contact load characteristics of synchromesh between the thread pair and gear pair in the planetary roller screw. According to the motion principle of planetary roller screw, the theoretical calculation formulas of the axial speed and displacement of nuts are derived, and the static load distribution model of thread tooth is provided. The numerical results are compared with the theoretical values in terms of kinematics and static loads, and the relative errors are both less than 5%, which verifies the correctness of the model. Based on the numerical model, the influence of different nut loads, screw speeds and friction coefficients on the dynamic contact load of each contact pair of planetary roller screw is analyzed. The results show that the fluctuation of contact load curves increases with the increase of screw speed, and the fluctuation of contact load curves between gear pair and roller shaft end and cage decreases periodically. The steady state contact load of the screw pair fluctuates slightly under the influence of the synchromesh of thread pair and gear pair and the meshing excitation of the gear pair. As the nut load increases, the contact load of all contact pairs(but the gear pair)increases in direct proportion. The thread pair and the cage share partial load of the gear pair, leading to the reduction of the contact load of the gear pair. As the friction coefficient increases, the contact load increases obviously, and the fluctuation of each contact load curve becomes larger.