摘要
提高精度是机械制造学科永恒的追求目标之一,随着精密机电产品不断追求更高精度,装配精度分析的精确性要求也在不断提高,在此背景下,提出综合考虑表面形貌与受力变形的装配精度分析方法。首先,以非理想表面模型为基础,通过小位移旋量模型以及基函数线性叠加方法分别对定位/定向误差、形状误差进行建模;并基于共轭梯度-快速傅里叶变换算法,建立不同类型非理想配合表面的接触变形计算方法;然后,以改进多面体模型进行装配偏差累积计算,实现了综合考虑表面形貌与受力变形的装配精度分析;最后,通过实例,对比分析了是否采用非理想表面模型以及是否考虑受力变形条件下装配精度分析的结果差异。数值研究结果表明,所提方法能够提高装配精度分析的准确性,从而为精密机械产品精度设计提供更为准确的指导。
Improving accuracy is one of the permanently pursued goals of the mechanical manufacturing discipline. With the continuous pursuit of higher precision for precision eletromechanical products, the accuracy requirements of tolerance analysis are also continuously improved. Hence, a method for assembly accuracy analysis with consideration of form defects and surface deformations is proposed. First, the positioning/orientation errors and form error are modeled by a small displacement torsor model and a linear basis function superposition method, respectively, based on the skin model shapes. Then, the contact deformations of different types of non-ideal matching surfaces are calculated by applying a conjugate gradient-fast Fourier transform algorithm. Thereafter, a modified polytope model is used to calculate the cumulative assembly deviations to achieve assembly accuracy analysis with a combined consideration of form defects and surface deformations. Finally, the differences of the instances considering the form defects and surface deformations whether or not are compared. The numerical results indicate that the proposed method can improve the accuracy of assembly accuracy analysis and provide more accurate guidance for product tolerance design.
作者
刘检华
张志强
夏焕雄
巩浩
邵楠
LIU Jianhua;ZHANG Zhiqiang;XIA Huanxiong;GONG Hao;SHAO Nan(School of Mechanical Engineering,Beijing Institute of Technology,Beijing 100081;Beijing Spacecraft,Beijing 100094)
出处
《机械工程学报》
EI
CAS
CSCD
北大核心
2021年第3期207-219,共13页
Journal of Mechanical Engineering
基金
国家自然科学基金(51935003)
北京市自然科学基金(3204054)资助项目。
关键词
装配精度分析
受力变形
表面形貌
公差分析
公差设计
assembly accuracy analysis
surface deformations
form defects
tolerance analysis
tolerance design
