斜齿行星传动多体动力学建模与分析

摘要

A multibody dynamic model for a helical planetary gear train (HPGT)was proposed and the dynamic performance of the HPGT system was analyzed.Its free vibration characteristics,steady-state dynamic responses and the effects of design parameters on the system dynamic behavior were investigated with numerical simulations.The free vibration of the HGPT was classified into 3 categories according to modal properties,such as,eigenvalue multiplies, modal coordinates of central components and coordinate ratios of planets.The classified vibration modes were axial translational and torsional mode (AT mode ),radial translational and rotational mode (RR mode )and planet mode (P mode).The characteristics of each category were presented.The simulation results agreed well with those using the previous discretized model neglecting the component flexibilities to validate the correctness of the proposed multibody dynamic model.The steady-state dynamic responses indicated that the dynamic meshing forces fluctuate about the average static values and the time-varying meshing stiffness is the major excitation of the system.The parametric sensitivity analysis showed that the floating sun gear and the reduction of circumferential assembly error of planets are effective to suppress the vibration of the HGPT.%建立了斜齿行星传动的多体动力学模型，对其进行了动态特性仿真，获知了该类系统的自由振动特性、稳态动力响应以及部分设计参数对系统动态特性的影响规律。根据系统特征值的重根数、中心构件的振型坐标及各行星轮间振型坐标的比例，将斜齿行星轮系的自由振动归结为3类典型振动模式，即：轴向平移-扭转振动模式、径向平移-扭摆振动模式和行星轮振动模式，并进一步给出了各类模式的特点。当不考虑构件自身柔性时，基于多体动力学模型的自由振动特性与前人的集中参数模型的仿真结果完全一致，表明了本文所建模型的正确性。斜齿行星轮系的稳态动力学响应表明，内、外啮合力在一个啮合周期内围绕静态均值作较大幅度的波动，而啮频激励是引起该类系统振动的主要原因。参数影响分析表明，构件支承刚度和行星轮周向安装误差对系统动态特性的影响明显，浮动太阳轮、严控行星轮周向安装误差可有效抑制系统的振动。