一种曲轴磨削砂轮架的结构动力学分析与优化

Dynamic analysis and structure optimization of a grinding carriage

以曲轴磨削砂轮架为研究对象,提出了一种平移-扭转集中参数模型作为基本分析模型。首先基于拉格朗日能量法推导出集中参数模型的控制方程,计算并分析机构的固有频率和模态振型;然后通过直接微分法计算固有频率对设计参数(包括支撑刚度、部件质量和惯性矩)的灵敏度系数;最后在灵敏度分析的基础上,得到了一种优化的参数修正方案。该模型清晰展现了系统的固有特性,优化后砂轮架系统固有频率比优化前平均提高了8%。

A translational and rotational lumped parameter model of a crankshaft grinding carriage is developed as the fundamental analysis model.The governing equations for the lumped parameter model are derived based on the Lagrange energy method.Subsequently,the natural frequency and modal shape of the machine are calculated and analyzed.Further,the sensitivity coefficients of the natural frequencies to design parameters,which include supporting stiffness,masses of parts,and moments of inertia,are computed by the direct differential method.The optimization of structure parameters is obtained according to the sensitivity analysis.The model clearly shows the inherent characteristics of the system.The frequency of all modes has an average increase of 8%through the optimization.