分段线性刚度能量阱及在端铣加工中的分析

Piecewise Linear Stiffness Energy Sink and Its Analysis in End Milling

为了解决用限制加工参数的方法降低端铣机床振动降低生产效率的问题,提出一种具有分段线性刚度的能量阱的方法。首先,介绍了此能量阱的结构和原理;其次,分析了分段线性刚度的性质;之后,列出了主轴-刀柄-刀具-能量阱系统的动力学微分方程组并对其用多自由度的增量谐波平衡法进行求解;最后,用数值仿真的方法探究了此能量阱对刀具端点的瞬态时域制振能力和稳态频域制振能力,对比了在安装此能量阱和不安装此能量阱的条件下,刀具端点在加工中的振幅。仿真结果表明,在端铣加工中,此能量阱具备实现带宽制振的能力,且刀具端点的振幅最多被减少40%。

In order to solve the problem of reducing the production efficiency by limiting the machining parameters to suppress vibration of the end milling machine tool,a kind of energy sink with piecewise linear stiffness is developed to satisfy the requirement.Firstly,the structure and work principles of piecewise linear stiffness energy sink are explained.Secondly,characters of piecewise linear stiffness are analyzed.Then,dynamic equations for the end milling machine tool's main spindle-handle-cutter-energy sink system are established and solved by multi-degree of freedom increment harmonic balance method.Finally,numerical simulation is carried out to study the vibration suppression capability of the energy sink in transient time domain and steady frequency domain,in which comparison is made between the vibration amplitude of cutter's endpoint with the energy sink and that without the energy sink.Simulation result shows the energy sink is effective at the suppression of broadband vibration in end milling process.Vibration amplitude of machine tool cutter’s endpoint can be reduced by 40%optimally.