高速立式加工中心滚珠丝杠螺母副动态特性分析

Dynamic characteristics analysis of the ball screw nut pair of high speed vertical machining center

为了研究高速立式加工中心的动态特性,对其进给系统进行模态分析和谐响应分析十分必要。根据高速立式加工中心的设计要求,基于Solid Works软件建立滚珠丝杠螺母副的三维模型并进行相应的简化处理,采用Hypermesh软件进行网格划分,并导入ANSYS软件中建立相应的有限元分析模型。针对滚珠丝杠螺母副的不同支撑方式和螺母所处丝杠位置,对其固有振动特性进行了模态分析,结果表明,两端固定支撑方式比其他支撑方式有更大的刚度。对滚珠丝杠进行了正弦载荷激励下的谐响应分析,找出了丝杠谐响应振幅最大时的频率,指出在实际工作状况中应尽量避免此频率下的动载荷。

In order to analyze the dynamic characteristics of high speed vertical machining center, the modal analysis and the harmonic response analysis of its feed system are necessary. According to the design requirement of high speed vertical machining center, it establishes the simplified 3D model of ball screw nut pair based on SolidWorks software, and realizes the mesh in Hypermesh software. According to different supporting modes and nut＇s different working position, it obtains the modal of the ball screw nut pair. The results show that the two ends fixed supporting mode has greater stiffness than other supporting mode. Finally, it realizes the harmonic response analysis under the sinusoidal loading to ball screw pair, finds the frequency which has biggest amplitude of harmonic response. It proposes that the dynamic load under this frequency should be avoided as far as possible in actual working condition.