第9期 2016年9月
组合机床与自动化加工技术
Modular Machine Tool & Automatic Manufacturing Technique
文章编号：10012265(2016)09004704
DO1:10. 13462/j. cnki. mmtamt. 2016. 09. 013
考虑砂轮磨损的精密数控磨床插补模型
及误差分析
刘清涛，蔡宗琰，宋效凯，王其锋
（长安大学道路施工技术与装备教育部重点实验室，西安
710064）
No.9 Sep.2016
摘要：为了减小圆柱形砂轮非均衡性磨损对磨削精度的影响，针对三自由度大型内外圆磨床的结构和工作机理，根据圆柱形砂轮的加工特性，建立了考虑砂轮磨损的大型精密数控磨床插补模型。采用等弧长策略离散出一系列刀触点，通过周期性改变圆柱形砂轮刀触点与刀位点距高的方法，修正刀位点坐标，使加工过程中砂轮表面的磨损尽量均匀，然后通过坐标变换，将刀具轨迹转化成机床工作台的平动和转动坐标，再经过插补运算，得到机床平动轴和转动轴的进给量，进而计算出相应的控制步进电机的脉冲数和脉冲分布，最后，对加工误差进行了分析。实例仿真表明，本模型能够有效减小砂轮的不均衡磨损，提高加工精度。
关键词：磨削加工；插补；砂轮磨损；误差分析
中图分类号：TH165;TG659
文献标识码：A
Interpolating Model of Precision Numerical Control Grinder Considering Grinding Wheel Wear and Its Error Analysis LIU Qing-tao,CAI Zong-yan, SONG Xiao-kai, WANG Qi-feng
( Key Laboratory for Highway Construction Technology and Equipment of Ministry of Education, Chang' an U-niversity，Xi'an 710064,China)
Abstract: To decrease the effect on grinding precision because of non-balance wear of cylindrical grinding wheel, the wear balance of cylindrical grinding wheel is an important factor that affects the precision of CNC grinding machine. For the structure and working mechanism of 3-DOF large internal and external cylindrical grinding machine, a interpolating model of precision numerical control grinder was established according to the characteristics of cylindrical grinding wheel. Firstly, A series of cutter contact points were discrete out by equal arc length strategies, and periodic changing the distance between those cutter contact points and their corresponding cutter location point, the coordinates of the cutter location points were obtained to a-chieve uniform wear of the wheel. Secondly, thought coordinate transformation, tool path was tum into translational and rotation coordinate of machine workbench, and then the feed rates of the translation and ro-onassoonoeaaeo was also obtained. Finally, the machining error was analyzed. The simulation results show that the model
can effectively reduce the uneven wear of the grinding wheel and improve the machining accuracy. Key words: grinding;interpolating;grinding wheel wear;error analysis
0
引言
磨削加工在特殊工件精密成形中占有重要地位。传统的磨削插补研究主要集中在插补速率和对特殊机型插补建模的研究上(14)。实践发现，在精密数控内外圆磨床磨前过程中，由于工件母线各处的曲率不同，为使加工过程平稳，需要确定各时间段中施加给电机的脉冲数和这些脉冲在该时段的分布，以控制各工作台的移动量或转动量，实现联动1"1。同时，圆柱形砂轮会
存在砂轮磨损的情况，常见的砂轮磨损有磨耗磨损、破碎磨损和砂轮的阻塞粘附"】，朱跃伟等人对高速磨削砂轮磨损进行了研究，考察了砂轮磨损对工件表面粗糙度、残余应力、表面金相组织和显微硬度变化的影响[7]。Daniela等人首先从理论角度分析了陶瓷CBN 砂轮磨削轴承的砂轮磨损情况，然后进行了试验验证(")。刘月明等人利用数值模拟和试验测量的方法揭示了修整工具磨损对砂轮磨削表面的影响[")。这一块的研究主要集中在砂轮磨损机理及其对磨前质量的影
收稿日期：2015-12-30
·基金项目：国家白然科学基金资助项目（5135042）：高等学校博士学科点专项科研基金资助项目（201320512004）作者简介：刘清涛（1981一），男，河南南阳人，长安大学讲师，博士，研究方向为数控技术，（E-mail)qtaolin@126.com。
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