C.-H. She et al. / Journal of Materials Processing Technology 177 (2006) 138–141 141

Fig. 4. The graphical output of the measured result.

error and the surface normal direction. Note that the points shown in red colour, e.g. P1, P3, P4, ... ,P22, are out of tol- erance. If the user clicks the “View NG Point” button, only the NG points will be displayed. Once the punch and the die are mea- sured, the “Spotting Clearance” button can combine the data for the punch and the die to calculate the spotting clearance. In gen- eral, the die maker repairs the stamping die on the spotting press using the red lead and hand repair tool. Since the spotting pro- cedure is usually performed many times, the spotting clearance is the important guidance for the die tryout.

6. Conclusion

A computer-aided measuring integration system for the sheet metal stamping die has been successfully developed, imple- mented and verified on an industrial stamping die. The proposed system is a CAD-based CMM software and analysis system that can analyze the NURBS surface and generate the DMIS output program. The CAD model of the die, the probe path and the projected dimensional error can be dynamically shown on the screen using the OpenGL language to assist the user to view the results easily and quickly. The result of this study can shorten the time-to-market effectively and increase the competitiveness for the mold and die industry.

Acknowledgements

The authors are grateful to the National Science Council of Taiwan and Drewloong Precision Machinery for supporting this

research under grant NSC 91-2622-E-212-009-CC3 and NSC 92-2622-E-212-012-CC3. The authors also would like to thank Jui-Li Enterprise for use of the CMM equipment and stamp- ing die. Thanks are also extended to graduate students Mr. Chen-Chih Yang and Mr. Ho-Pao Chang for their experimen- tal assistance.

摘要：本文根据设计和制造特点的要求，开发了基于CAD三坐标测量机（CMM）软件和分析系统的金属板料冲压模具。该系统可以分析NURBS IGES格式模具表面模型和DMIS格式以及探针路径模拟生成测量程序。此外，该系统通过集成的模具CAD模型和测量信息显示的测量位置和尺寸误差，已经开发完成了窗口图形界面。它不仅可以用于模具质量的诊断，而且还可以改善车间工艺和提供模具抛光指导。实际测量的一组工业薄板冲压模具的CMM验证所开发的系统的有效性。

毕业论文关键词: 冲压模具; 坐标测量机

1. 介绍

模具行业是大规模技术和高附加价值的行业。对产业竞争力的模具质量的重要性越来越大，测量技术已成为一个重要的问题。相比传统的机床、坐标测量机（CMM），已装有触发式探头，可以检查专用产品更迅速、准确地利用计算机数值控制加工误差，已广泛应用于工业。然而，大部分的数据仍然是合格的几何尺寸的鉴定或设计要点，并不能对模具的试模提供有用的信息。

模具和模具的形状往往是由复杂的或自由曲面的变曲率的高多项式设计。通常，主模型是需要模具制造工艺和手工雕刻雕刻。然后在轮廓铣床加工，它使用一个主模型来引导刀具。在模具制造过程中，最终的模具和通常不符合图纸上细节，由于不准确的加工和主模型。计算机辅助几何设计的出现，极大地解决了这个问题。模具和模具可以直接由计算机数控（CNC）机与计算机辅助设计（CAD）和计算机辅助制造（CAM）软件。

使用CMM测量自由曲面是十分困难的，因为表面法线方向的探测点要计算以补偿探头的直径。有必要采用CAD引导技术产生探测点和探测路径。以作者的了解，各种研究已验证了开发一个CMM检查路径规划和已经解决了发展的CMM系统专用的冲压模具。另一方面，目前大多数商业CMM包如PC-DMIS ，卡普斯和silma CAMIO支持CAD指导检查计划。但是，他们是通用包装年龄设计的自由曲面表示的各种组件是十分昂贵的。来!自~优尔论-文|网www.youerw.com