1、摘 要 机械传动中，由回转运动变为往复运动，往往是由偏心轴和曲轴来完成的。机械 的开会和缩紧也往由偏心零件来完成的，可见偏心零件在机械制造中运用的非常广泛。 本课题来源于生产实践，充分利用所学的机械制图、机械设计及机械制造等课程， 了解针对偏心工件的特点，通过 CAD 软件，利用该软件制图功能，完成偏心工件类零件 偏心外圆车组合夹具的设计。 通过分析偏心工件类零件传统加工手段和三爪微调车削法, 得出了加工困难、 效率低、 互换性差及精度不易保证的结论,针对其缺陷提出了高效 加工高精度偏心工件类零件的工艺方案组合夹具车削法。 加工精度要求比较高或批 量较大的偏心工件类零件的车削加工,均适合采用专
2、用夹具车削法。 在课题的研究设计阶段，首先从众多的零件中选择一个作为设计夹具的零件。针对 该零件的结构特点，制定该零件的加工工艺。其次要了解夹具的相关知识，结合零件的 结构特点选择需要的夹具元件，设计出夹具的大体结构。 机床夹具作为一种重要的工艺 装备在机械制造工艺过程中起着十分重要的作用，它的设计不但要保证工件的加工质 量，提高加工效率，降低成本，在操作维护中安全方便还要注意到夹具结构的标准化， 夹具制造的精密化。为了保证夹具组装精度，需要学习了解工件定位原理。根据这些原 理结合零件的结构特点确定零件在夹具中以轴外圆作为定位， 计算夹具的定位精度与夹 紧力保证零件在夹具上的加工精度。然后使用
3、 CAD 绘图软件参考夹具设计手册绘制 夹具元件的机械图，完成夹具的设计。 关键词：偏心 偏心距 圆度误差 加工工艺 工件定位 Abstract This topic comes from production practice, make full use of what have learned mechanical drawing, mechanical design and mechanical manufacturing, and other programs, to understand the characteristics for the eccentric shaft, th
4、rough the CAD software, the use of the software mapping function, complete with eccentric shaft parts special combination jig turning design. In this paper , the traditional process methods and the three jaw fine tuning turning method were analyzed , afterthat , a conclusion that the process on ecce
5、ntric shaft parts are difficulties , low efficiency , poor interchang eability and difficult toguarantee the accuracy can be drawn . Finally , according to the shortcomings of the original process methods , a technology program for process high precision eccentric shaft parts special combination jig
6、 turning method is put forward In the research projects in the design phase, first select from a number of parts as the design of a fixture parts. For that part of the structural characteristics of the development of the parts processing technology. Second, we must understand the fixture knowledge, combined with the structural features of components select the required fixture components, the general structure of fixture design. As an important fixture of the technology and equipment in
