摘要
为解决重型数控机床热误差严重的问题,提出一种基于线性回归的热误差分离和建模方法.对机床的几何误差与热误差进行分离,得到相应的热误差参数;结合主因素和互不相关等温度传感器优化布置策略,选出相应的热误差关键点;采用线性回归理论进行热误差的建模.在一台型号为TK6920的重型数控落地铣镗床上进行了立柱热倾斜误差补偿实验.结果表明:利用所建立的热误差模型进行补偿,立柱在X和W方向的直线度误差分别由0.45 mm和0.25 mm降到了0.13 mm和0.09 mm,补偿率分别为71%和64%.采用误差补偿技术可降低重型数控机床的热误差,从而提高其加工精度.
To solve the problem of thermal error of heavy-duty CNC machine tools, a thermal error separating and modeling approach based on linear regression theory is proposed. Firstly, the thermal errors are separated from geometric error to get thermal error parameters. Secondly, based on temperature sensors optimizing distri- bution strategies, like main factor strategy and irrelevance strategy, the key points of thermal errors are select- ed. Finally, a multiple linear regression model is constructed for thermal errors, and an experiment is carried out on a TK6920 heavy-duty CNC floor-type boring and milling machine tool, and the results indicate that the thermal error of column is reduced from 0. 45 mm and 0.25 mm to 0. 13 mm and 0.09 mm in X and W direc- tions, that is 71% and 64% of thermal error can be compensated with this model. Error compensation tech- nology can reduce the thermal error of heavy-duty CNC machine tools, therefore the manufacturing precision can be improved.
出处
《哈尔滨工业大学学报》
EI
CAS
CSCD
北大核心
2012年第9期51-56,共6页
Journal of Harbin Institute of Technology
基金
国家科技重大专项资助(2009ZX04014-025)
关键词
重型数控机床
热误差
误差分离
误差建模
误差补偿
heavy-duty CNC machine tools
thermal error
error separating
error modeling
error compensation
