摘要
刀具偏心可能导致铣削力的大幅度波动。为辨识铣刀偏心状态,研究偏心作用下的铣削力变化规律。推导出以主轴旋转角和切削刃序号为变量的单刃瞬时铣削力表示式,发现铣削力峰值是切削刃序号的离散正弦函数,其均值为无偏心铣刀的公称力,波动部分为偏心引起的铣削增力。该铣削增力与旋转主轴同频,其初始相位依赖于偏心角,其幅值与偏心距和轴向切深成正比例关系,而与每刃进给量不相关。基于此发现,提出一种估算偏心角和偏心距的数据拟合方法,该方法主要对各刃的铣削力峰值进行正弦函数拟合,算法简单,且只需要做一次铣削测试。铣削试验结果与以上发现一致,且表明该估算方法有效。研究揭示与偏心相关的铣削力峰值特性,提出一种简单直观的偏心尺寸估算方法。研究成果可用于铣削过程状态辨识。
The eccentricity of cutter may induce great variation of milling force. In order to identify the geometry of eccentricity, regularities of milling force varying with eccentricity are studied. Milling force on single edge is mathematically expressed as functions of the rotation angle and the sequence number of curer edge. By mathematically deducing, the peak milling force of each curer edge is found to be a discrete sine function of only the sequence number, its mean part be the nominal force without curer eccentricity, and the variable part be the increment force induced by eccentricity, moreover, the increment force be same with spindle rotation in frequency, its initial phase be dependent on the angle of eccentricity, and its amplitude be in direct proportion to both the distance of eccentricity and axial milling depth, but irrelevant to feed per tooth. Based on these findings, a kind of data fitting method is present to estimate the distance and angle of eccentricity, which is mainly to fit peak milling forces of every curer edge with sine function. This method is simple, and needs only one milling test. The results of milling experiment agree with above findings, and show that this estimation method is validate. This study reveals the eccentricity-relate characteristics of peak milling force, and presents a simple method of estimating the geometry of eccentricity. Study results can be used in identifying the state of milling process.
出处
《机械工程学报》
EI
CAS
CSCD
北大核心
2013年第1期185-190,共6页
Journal of Mechanical Engineering
基金
国家自然科学基金资助项目(50975053)
关键词
刀具偏心
尺寸估算
铣削力峰值
特性
拟合
Cutter eccentricity Geometry estimation Peak milling force Characteristics Fit
