基于能量分布的机床整机动态特性优化方法

发布时间：2018-02-03 08:38

本文关键词： 能量分布结合部立式加工中心整机动态特性有限元分析　出处：《振动.测试与诊断》2015年06期 　论文类型：期刊论文

【摘要】：基于机床结构中的能量分布,在准确建立立式加工中心整机有限元模型的基础上提出一种整机动态性能优化方法。采用弹簧阻尼系统等效结合部的接触特性,基于辨识的结合部等效刚度和阻尼值在Ansys中建立了立式加工中心整机有限元模型,对整机进行模态分析和谐响应分析。通过整机模态试验验证了该有限元模型的准确性,并根据有限元分析与试验结果确定整机的薄弱模态。计算薄弱模态下整机、结合部的弹性能以及结合部在整机中的弹性能分布率,以分布率较高的结合部作为薄弱结合部。基于薄弱结合部的等效接触刚度提出优化方案,优化后薄弱结合部的弹性能分布率明显降低,主轴轴端的动态响应幅值降低,从而使整机动态性能得到改善,验证了该优化方法的可行性。
[Abstract]:Based on the energy distribution in the structure of the machine tool, a dynamic performance optimization method is proposed based on the accurate finite element model of the vertical machining center. The contact characteristics of the equivalent joint of the spring damping system are adopted. The finite element model of vertical machining center is established in Ansys based on the equivalent stiffness and damping of the joint. The modal analysis and harmonic response analysis of the whole machine are carried out. The accuracy of the finite element model is verified by the modal test of the whole machine. According to the finite element analysis and test results, the weak mode of the whole machine is determined. The elastic energy of the joint part and the distribution rate of the elastic energy of the joint part in the whole machine are calculated under the weak mode. Based on the equivalent contact stiffness of the weak joint, the optimal scheme is put forward. The elastic energy distribution rate of the weak joint is obviously reduced after the optimization. The dynamic response amplitude of the spindle shaft is reduced, thus the dynamic performance of the whole machine is improved, and the feasibility of the optimization method is verified.
【作者单位】：四川大学制造科学与工程学院;成都普瑞斯数控机床有限公司;
【基金】：国家科技重大专项资助项目(2013ZX04005-012) 四川省科技支撑计划资助项目(2012GC0008)
【分类号】：TG502
【正文快照】： 引言随着机床加工性能的不断提高,对机床动态性能的要求也越来越高。机床是由许多零部件按特定的要求结合起来的,其结合面的阻尼、刚度分别占整机阻尼和刚度的90%和60%以上[1];因此,为准确地对立式加工中心进行整机动态特性分析,须基于结合部建立准确的动力学模型。Zhang等[1]

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