Dynamic Modeling Of The Ballscrew’s Movable Joint With Finite Element Mothed

With development of high-speed and high-precision machine tools, ballscrew with goodperformance has been widely needed and increasingly becoming a functional component inhigh-technique CNC machine tool. The dynamic characteristics of movable ballscrew joint iskey factor determining dynamic behavior of machine tool,and related research are importantto structural dynamic design and optimization of machine tool.So far there is little systematic research and verification about movable ballscrew pairjoint，which leads confusion on dynamic characteristic of driving system and ballscrew joint.This dissertation introduces hammering method to measure dynamic characteristic ofballscrew with different structural forms by using LMS modal testing system in Hanjiangmachine tool factory. The effective frequency range is calculated by measured mode shapes ofvarious orders, which determine finite element size of substructure in ballscrew byminimum-wavelength principle.The model of ballscrew joint is obtain by integrating elementmodels of all substructures in ballscrew. The parameters of ballscrew joint are calculatedbased on frequency response function obtained by recognition technology, which layfoundation for mathematical model of ballscrew.The mathematical model of ballscrew is verified by finite element analysis and modeltest. And using with the ballscrew model with Okwudire joint model as a reference.Acomparison of analyzed results and experiment result is conducted by model shapeidentification, which denotes the correctness of finite element model and excellent ofballscrew pair joint modeling.This dissertation provides a reasonable finite element model and theoretical basis forresearch and optimization of ballscrew.