级进模条料设计过程中的主要难点在于中间构形的设计。针对级进模成形以弯曲变形为主的特点,提出了一种基于旋转变形的中间构形快速生成算法,该算法通过设置最终构形的旋转轴、固定区、变形区、非变形区、固定约束、形状约束、等长线以及旋转角度等求解条件,通过曲面网格快速求解出中间构形,并以生成的中间构形网格作为参考构形,采用有限元逆算法,将最终构形展开到中间构形上以精确地获取中间构形的修边线。介绍了中间构形生成算法的实现流程,并在SolidWorks平台下采用二次开发技术,开发了一套完全无缝集成的级进模条料分步展开系统SW-CUX。以复杂连续折弯件的中间构形设计为例验证了该算法的可行性。
The main difficult of the progressive die strip layout design lies in the design of intermediate shapes. Consid- ering the situation that the progressive die forming is dominated by bending deformation, a fast generating algorithm of intermediate shapes based on the rotation deformation was developed. In this algorithm, some conditions, such as the rotation axis, fixed area, deforming area, un-deforming area, fixed restraint line, shape restraint line, constan~length line and rotation angle were considered. The intermediate shapes were solved by surface mesh. The generated interme- diate shapes were considered as reference configuration, and the final configuration was unfolded to the intermediate shape to obtain the accurate trimming line. The realization flow of the intermediate shape generating algorithm was intro- duced. A seamless integration system SW-CUX for multi-step unfolding of progressive die strip was developed by SolidWorks APL The feasibility of the algorithm was verified with the intermediate shape design of a complex bending part.