CAJ | 학술논문

针对现有的基于响应耦合子结构法(RCSA)的刀尖点频响函数预测方法需要辨识主轴刀柄、刀柄刀具结合面参数以及需要自制刀柄模型等引起的预测误差和预测过程复杂等问题，提出一种改进的基于 RCSA 的铣刀刀尖点频响函数预测方法。该方法首先改进已有的子结构划分方法，将机床主轴刀柄刀具系统划分为机床主轴刀柄部分刀杆、剩余刀杆和刀齿三个子结构；然后改进主轴刀柄处转动频响函数的计算方法，通过铣刀的模态锤击实验采用反向 RCSA 和有限差分法计算机床主轴刀柄部分刀杆结构的转动频响函数，并基于 Euler 梁模型计算出剩余刀杆、刀齿子结构的频响函数；最后将三个子结构的频响函数耦合确定刀尖点的预测频响函数。以一立式加工中心为研究对象，应用所提出的方法对铣刀刀尖点的频响函数进行了预测，并与其实测频响函数进行对比。对比结果表明：刀尖点的预测频响函数与实测频响函数符合程度较高，其预测、实测前三阶固有频率之间的误差在6.9%以内，所提出的方法可行有效、简单方便，且可直接基于铣刀的模态实验计算主轴刀柄的频响函数，避免了相关结合面参数的辨识和刀柄模型的制作。
침대현유적기우향응우합자결구법(RCSA)적도첨점빈향함수예측방법수요변식주축도병、도병도구결합면삼수이급수요자제도병모형등인기적예측오차화예측과정복잡등문제，제출일충개진적기우 RCSA 적선도도첨점빈향함수예측방법。해방법수선개진이유적자결구화분방법，장궤상주축도병도구계통화분위궤상주축도병부분도간、잉여도간화도치삼개자결구；연후개진주축도병처전동빈향함수적계산방법，통과선도적모태추격실험채용반향 RCSA 화유한차분법계산궤상주축도병부분도간결구적전동빈향함수，병기우 Euler 량모형계산출잉여도간、도치자결구적빈향함수；최후장삼개자결구적빈향함수우합학정도첨점적예측빈향함수。이일입식가공중심위연구대상，응용소제출적방법대선도도첨점적빈향함수진행료예측，병여기실측빈향함수진행대비。대비결과표명：도첨점적예측빈향함수여실측빈향함수부합정도교고，기예측、실측전삼계고유빈솔지간적오차재6.9%이내，소제출적방법가행유효、간단방편，차가직접기우선도적모태실험계산주축도병적빈향함수，피면료상관결합면삼수적변식화도병모형적제작。
on RCSA needed to identify the joint parameters of the spindle-holder and holder-tool joints and to The present predicting methods of tool point frequency response function (FRF)based manufacture the artificial tool-holder model,which will result in predicting errors and complexity,ai-ming at these problems,this paper presented an improved tool point FRF predicting method based on the RCSA.This method firstly improved the present substructure separating methods,and separated the machine-spindle-holder-tool structure into three parts:the machine-spindle-holder-partial tool bar,the remaining toolbar and the tool tooth;then improved the method for calculating the rotating FRFs of the machine-spindle-holder-partial tool bar through inverse RCSA and finite difference meth-od by applying modal impact test on the toolbar,and calculated the FRFs of the remaining toolbar and tool tooth using Euler beam theory;finally the tool point FRF was predicted by coupling the three parts’FRFs.Experiments conducted on a machining center show that the predicted and measured y to carry out,it can compute the spindle-holder’s rotating FRFs directly based on the tool modal ex-the predicted and measured FRFs are within 6.9%,the proposed method is feasible,effective and eas-tool point FRFs are in good agreement,the error between the first three order natural frequencies of p e r i m e n t s , a v o i d i n g t h e i d e n t i f i c a t i o n o f t h e j o i n t p a r a m e t e r s a n d t h e m a n u f a c t u r i n g o f t h e h o l d e r m o d e l .