等端切角法加工高次非球面原理及工艺分析  

Principle for high-order aspherical machining by constant tangent-face angle method and grinding process analysis

作　　者：刘海涛 王银河[1] 李野[1] 吕少波[1] 宋光辉[1] LIU Haitao;WANG Yinhe;LI Ye;LV Shaobo;SONG Guanghui(Shenyang Academy of Instrumentation Science Co.Ltd.Hb-optical,Liaoning 110043,China)

机构地区：[1]沈阳仪表科学研究院有限公司汇博光学,辽宁沈阳110043

出　　处：《光学技术》2021年第1期31-36,共6页Optical Technique

基　　金：国机集团科研院所技术开发研究专项资金项目(2018SMC119115)。

摘　　要：基于Z、X、B三轴联动的数控机床,提出了一种高次非球面的等端切角加工方法,采用等弦长离散非球面型线,并保持端切角恒定来计算数控机床的运行轨迹。等弦长可避免非球面型线因斜率变化引起的加工误差,等端切角加工方法保证磨头同一工作点完成工艺过程,提高加工精度和工艺稳定性。另外,通过编程模拟了等端切角法加工高次非球面的工艺过程,分析了端切角δ和距离C对机床工艺行程的影响,并指出两个参数的选取应使机床工艺行程满足:不存在磨头与工件之间的物理干涉;不存在Z、X向导轨和B轴的反向运行,避免将传动间隙误差引入到工件中;运行控制点的步距不得小于设备运行精度,避免机床跨点突进产生棱带误差;机床运行的工艺行程应尽量小以提高加工效率。因磨头磨损带来的加工误差,可通过磨头修锐或使用磨损边缘点作为工作点并重新编制数控加工程序来消除。Based on the Z/X/Btriaxial CNC machine,a constant tangent-face angle(CTFA)method for high-order aspherical grinding is proposed.In this method,equal chord length is used as the criterion to dissociate the profile of the aspherical,and the tangent-face angle is assumed as a constant to calculate the running process of CNC machine.The equal chord length criterion can avoid excessively step of the profile dissociation which was caused by the slope gradual change,and CTFA method makes the grinding wheel to finish the grinding process kept using front face edge,which helps to achieve a aspherical surface in high precision and consistency.In addition,the grinding process with CTFA method is simulated by computer programming and the result shows that,parametersδand Cshould make the running of CNC machine meets the conditions of no physical collision between the work piece and machine components,no reverse running of CNC machine in treble Z/X/Bdirection,running step must not smaller than the resolution of CNC machine and to make the process route of the machine as short as possible.The deviation of aspherical surface caused by grinding wheel abrasion can be relieved by reprogramming the CNC process after the working edge was sharpened or take the abrasion edge of the wheel as the working edge.

关 键 词：高次非球面 点磨削 等弦长离散 等端切角 

分 类 号：TH161[机械工程—机械制造及自动化]