运动结合部的非线性对大型数控机床动力学特性的影响

Effects of nonlinearity of traveling joints on dynamics characteristics of large-scale NC machine tool

为了提高大型数控机床的加工性能,从非线性动力学的角度考察运动结合部对机床动态特性的影响。针对某大型数控铣齿机床样机,建立包含运动结合部非线性的简化动力学模型,采用数值仿真算法求解模型的时域响应,通过快速傅里叶变换得到了关于动柔度的频域响应,并比较线性和非线性模型的响应差异,最后给出计算值和在机床样机上试验测量值的比较。结果表明,运动结合部的非线性显著影响了机床结构的共振行为和动柔度。

To improve the machining performance of large-scale numerical control（NC） machine tool,the effects of traveling joints on the dynamical property of machine tool were investigated based on the nonlinear dynamics.Aimed at a prototype of large-scale machine tool for milling gears,a simplified dynamics model including the nonlinear traveling joints was established.The time domain response of the model was solved by numerical simulation method,and the frequency domain response about the dynamic compliance was obtained through fast Fourier transform.The response differences between the linear and nonlinear models were compared,and experiment verifications were also performed on the prototype.The results indicated that the nonlinearity of traveling joints significantly influenced the resonant behavior and dynamic compliance.