自由曲面薄壁类零件的仿形装夹优化研究

Optimization on coping clamping of thin-wall parts with sculptured surface

针对大型自由曲面的薄壁件在加工中易发生变形的问题,提出结构模块化仿形定位/支撑,真空吸附夹紧的装夹理念,即由夹具定位/支撑点包络的曲面与被加工曲面的形状保持一致,真空吸附保证这些区域夹紧力均匀。开发曲面薄壁件的夹具系统模型,提出关于曲面薄壁零件等效刚度的概念。通过ANSYS的APDL语言和模拟退火遗传算法相结合的寻优途径,实现定位/支撑模块所需数量最少、布局方式最优的状态,从而提高薄壁件的等效刚度。通过对曲面工件进行模拟仿真,证明上述方法的可行性。

Aiming at deformation problem of large thin-wall parts when processing and manufacturing,an idea that parts are positioned or supported by modular structures and clamped by vacuum operator,i.e. the surface which is formed by locating or supporting points keeps the same with the surface of the part was proposed. The means of clamping with vacuum ensures uniform clamping force. The vacuum fixture structure of thin-walled parts was designed and the concept of equivalent stiffness about thin-walled parts was proposed. Finally,combining APDL language of ANSYS with genetic algorithm（GA）,the optimal state that requires the least amount of modular structure and the most reasonable layout were attained.