摘要
机床主轴高速运转产生离心力导致夹紧力显著衰减,影响工件加工精度和安全性。为补偿因高速运转引起的夹紧力降低,设计一种基于压力调节的气动卡盘夹紧力回路系统,通过夹紧力衰减的反馈,调节缸内压力以维持夹紧力稳定。分析系统的补偿性能,基于卡盘静态力与动态力方程、气体连续性方程及流量方程等,建立系统的数学模型,并利用AMESim搭建系统仿真模型,通过参数辨识确定摩擦力等相关参数。对系统的压力动态响应进行研究,以腔内目标压力与实际压力的差最小为目标,通过全因子实验设计获得对压差影响显著的关键参数,并采用序列二次规划算法对关键参数进行优化。仿真结果表明:在最优参数组合下,卡盘腔内的压力高于目标压力,误差控制在0.1%左右,且压力上升迟滞时间为0.02~0.04 s;对于缸径100 mm、楔角15°的楔式气动卡盘,随着转速增大,相较于未采用补偿的系统,采用供气补偿系统的夹紧力衰减后可以在0.1~0.2 s内有效恢复至初始压力下的静态力值。在压力0.6 MPa、转速3000 r/min时,夹紧力降低为12.62 kN后能够恢复至静态值18.84 kN,提升了33%。系统夹紧力的补偿满足国标中对于夹紧力的要求。
The centrifugal force generated by the high-speed operation of the machine tool spindle leads to a significant attenuation of the clamping force,which affects the machining accuracy of the workpiece and safety.To compensate for the reduction of clamping force caused by high-speed operation,a pneumatic chuck clamping force circuit system was designed based on pressure regulation.The cylinder pressure was regulated to maintain the clamping force stable through the feedback of clamping force degradation.The compensation performance of the system was analyzed,a mathematical model of the system was established based on the static and dynamic force equations of the chuck,the gas continuity equation and the flow equation,etc.A system simulation model was constructed using AMESim,and relevant parameters such as friction force were determined through parameter identification.The pressure dynamic response of the system was studied,and with the objective of minimizing the difference between the target pressure and the actual pressure in the cavity,the key parameters that had a significant effect on the pressure difference were obtained through the full factorial experimental design,and the key parameters were optimized by using the sequential quadratic programming algorithm.The simulation results show that under the optimal parameter combination,the pressure inside the chuck cavity is higher than the target pressure,with the error controlled within approximately 0.1%,and the pressure rise lag time is from 0.02 s to 0.04 s.For a wedge-type pneumatic chuck with a cylinder diameter of 100 mm and a wedge angle of 15°,when the rotational speed increases,compared to the system without compensation,the clamping force of the system with the air supply compensation can effectively recover to the static force value under the initial pressure within approximately 0.1 s to 0.2 s after degradation.At a pressure of 0.6 MPa and a rotational speed of 3000 r/min,the clamping force is able to recover to the static value of 18.84 kN after decreasing to 12.62 kN,with an improvement of 33%.The compensation of the system clamping force meets the requirements for clamping force specified in the national standard.
作者
虞启辉
韩镇杰
张建龙
孙永涛
秦日鹏
孙国鑫
YU Qihui;HAN Zhenjie;ZHANG Jianlong;SUN Yongtao;QIN Ripeng;SUN Guoxin(School of Mechanical Engineering,Inner Mongolia University of Science&Technology,Baotou Inner Mongolia 014010,China;Inner Mongolia Key Laboratory of Intelligent Diagnosis and Control of Mechatronic System,Baotou Inner Mongolia 014010,China;Guangdong Fenghua Advanced Technology Holding Co.,Ltd.,Zhaoqing Guangdong 526040,China)
出处
《机床与液压》
北大核心
2025年第22期224-232,共9页
Machine Tool & Hydraulics
基金
国家自然科学基金地区科学基金项目(52465008)。
关键词
气动卡盘
夹紧力
参数辨识
压力调节补偿
pneumatic chuck
clamping force
parameter identification
pressure regulation compensation
