Acceleration-Dependent Analysis of Vertical Ball Screw Feed System without Counterweight  

作　　者：Cunfan Zou Huijie Zhang Jun Zhang Dongdong Song Hui Liu Wanhua Zhao 

机构地区：[1]State Key Laboratory for Manufacturing Systems Engineering,Xi’an Jiaotong University,Xi’an 710049,China

出　　处：《Chinese Journal of Mechanical Engineering》2021年第3期243-255,共13页中国机械工程学报（英文版）

基　　金：Supported by Key Program of National Natural Science Foundation of China(Grant No.51235009);National Natural Science Foundation of China(Grant No.51605374).

摘　　要：The distinguishing feature of a vertical ball screw feed system without counterweight is that the spindle system weight directly acts on the kinematic joints.Research into the dynamic characteristics under acceleration and deceleration is an important step in improving the structural performance of vertical milling machines.The magnitude and direction of the inertial force change significantly when the spindle system accelerates and decelerates.Therefore,the kinematic joint contact stiffness changes under the action of the inertial force and the spindle system weight.Thus,the system transmission stiffness also varies and affects the dynamics.In this study,a variable-coefficient lumped parameter dynamic model that considers the changes in the spindle system weight and the magnitude and direction of the inertial force is established for a ball screw feed system without counterweight.In addition,a calculation method for the system stiffness is provided.Experiments on a vertical ball screw feed system under acceleration and deceleration with different accelerations are also performed to verify the proposed dynamic model.Finally,the influence of the spindle system position,the rated dynamic load of the screw-nut joint,and the screw tension force on the natural frequency of the vertical ball screw feed system under acceleration and deceleration are studied.The results show that the vertical ball screw feed system has obviously different variable dynamics under acceleration and deceleration.The influence of the rated dynamic load and the spindle system position on the natural frequency under acceleration and deceleration is much greater than that of the screw tension force.

关 键 词：Vertical ball screw feed system Acceleration and deceleration Joints stiffness Variable-coefficient lumped parameter model Power spectral density Natural frequency 

分 类 号：TG502.3[金属学及工艺—金属切削加工及机床]