基于可编程电涡流阻尼器的高速机床移动部件智能抑振机理研究

The dynamic characteristics and excitation loads of high-speed machine tools change constantly during machining which will cause multi-frequency vibration in the displacement fluctuation of the moving parts, such as table and spindle box. The multi-frequency vibration has great effect on the stability of the control system and the surface quality of the workpiece. At present, the existing vibration suppression methods are difficult to suppress the multi-frequency vibration of moving parts during machining of different parts. In this project, programmable eddy current dampers are proposed for the vibration suppression of moving parts of high-speed machine tools. Intelligent vibration suppression of moving parts is realized by investigating the vibration suppression mechanism of the programmable eddy current damper. An electromechanical coupling model for high-speed feeding systems is established to study the effect of multiple modes on the displacement fluctuation of the moving parts. Then, the mechanism of the eddy current damping system to suppress the displacement fluctuation of the moving parts is analyzed by the dynamic equations of the high-speed linear axis-eddy current damping system. Aiming at minimizing the amplitude of vibration displacement of moving parts under multi-frequency excitation loads, the layout and structure parameters of the eddy current dampers are intelligently decided by using the genetic algorithm, and the dynamic characteristics of the moving parts are actively adjusted. Finally, an eddy current damping system is designed for the linear axis of a high-speed vertical machining center and its vibration suppression performance is verified. This project establishes a theoretical foundation for controlling of structural vibration, developing of vibration suppression devices and designing of intelligent components of high-speed machine tools.

高速机床的动特性和激励载荷在加工过程中不断变化，两者的共同作用使得工作台、主轴箱等移动部件的运动位移存在多频振动成分，显著影响控制系统稳定性和零件的表面质量。目前的抑振措施难以适应不同零件加工过程中移动部件多频振动位移的变化。本项目提出了一种应用于高速机床移动部件的可编程电涡流阻尼器，通过其抑振机理研究以实现移动部件振动抑制的智能化。建立高速进给系统的机电耦合模型，研究多阶模态对移动部件振动位移的影响。进而，通过高速直线轴-电涡流阻尼器系统的动力学方程，分析电涡流阻尼器对移动部件振动位移的抑制机理。以多频激励力作用下移动部件振动位移幅值最小为目标，通过遗传算法对电涡流阻尼器的布局和结构参数进行智能决策，实现移动部件动特性的主动调整。最后，针对高速立式加工中心的直线轴设计电涡流阻尼器系统并对其减振性能进行验证。本项目的研究可为高速机床的结构振动控制、减振装置开发和智能部件设计提供理论依据。

高速机床的动特性和激励载荷在加工过程中不断变化，两者的共同作用使得工作台、主轴箱等移动部件的运动位移存在多频振动成分，显著影响控制系统稳定性和零件的表面质量。目前的抑振措施难以适应不同零件加工过程中移动部件多频振动位移的变化。本项目建立了高速滚珠丝杠进给系统的变系数动力学方程，求解得到了其模态参数随移动部件位置的演变规律，进而建立机电耦合模型研究了高速滚珠丝杠进给系统的位移、速度和加速度特点以及运动精度表征方法。测试和计算了高速机床内外载荷的时域和频域特征，建立高速机床整机混合动力学模型研究固有频率和振型的分布规律，开发了高速机床的载荷谱和动态性能分析系统，实现了高速机床进给系统和整机动态性能的快速分析，构建了高速立式加工中心和蜗杆砂轮磨齿机的载荷频谱和结构模态分布图。设计了面向多频激励的二维可编程减振器，建立其动力学方程分析了固有频率随弹簧片布局和结构参数的变化规律，开发了弹簧片刚度优化设计方法实现了弹簧片结构参数的主动设计。进而建立进给系统-减振器系统的动力学建模分析了振子特征频率和数量对转台台面原点频响函数抑振区域宽度和动态响应的影响规律。在此基础上，研究了在多频激励作用下可编程减振器布局和结构参数优化的优化算法，优化后显著减小了多频激励作用下转台台面的转角误差。本项目的研究可为高速机床的结构振动控制、减振装置开发和智能部件设计提供理论依据。