编号
毕业设计(论文)
普通车床拨叉加工工艺及夹具设计
Ordinary Lathe Fork Processing Technology and Fixture Design
院（系）名称 辽宁工业大学继续教育学院 专 学 学 指
业名称 生姓名
号
导教师
机械设计制造及其自动化
贾成真 142110105 王晓东 教授
2016年5月20日
继续教育学院专科生毕业设计（论文） 摘 要
此毕业设计是对车床拨叉加工工艺的分析并针对镗削工序进行专用夹具的设计，拨叉零件为铸件，是车床重要的零件之一，具有体积小，形状不规则的特点，在加工时工装不容易实现，因此需要设计一套专用夹具，完成镗孔工序的加工。在制定工艺规程时，要确定各工序的安装工位、加工基准、刀具和加工用量。由于面比孔易加工，因此应先加工面，再以面为基准来加工其它的表面，其中各工序夹具采用专用夹具，特别的对于加工大头孔、槽和小头孔斜面小孔的工序中，选一面两销的定位方式，并以操作简单的手动夹紧方式夹紧，其机构设计简单，方便且能满足要求，为保证拨叉的加工质量，降低劳动强度，提高生产效率，降低劳动成本，而设计一套专用车床夹具。
关键词： 加工工艺，加工工序，专用夹具设计，CAD
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继续教育学院专科生毕业设计（论文） Abstract
This graduation design is on the lathe shifting fork processing analysis and in the boring and cutting process of special fixture design, dial fork spare parts for the casting, is one of the important parts of the lathe, has the advantages of small size, characteristics of irregular shape, in the process of tooling is not easy to achieve, so it is necessary to design a special fixture, boring process of processing. In the development of the process, to determine the process of the installation station, processing standards, cutting tools and processing dosage. Due to surface pore easy processing, so it should be first processed surface to surface as a benchmark to processing the rest of the surface of the, of which each working procedure jig using special fixture, special for processing big hole, a groove and a small head hole slant hole process, select a two pin positioning and to manipulate as simple manual clamping fixture, the mechanism design simple, convenient and can meet the requirements, in order to ensure the dials the fork processing quality, reduce labor intensity, improve production efficiency, reduce the labor cost, and the design of a special lathe fixture.
Keywords: machining process, machining process, special fixture design, CAD
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继续教育学院专科生毕业设计(论文) 目 录
第1章 绪 论................................................................................................................ 1 第2章 拨叉的加工工艺规程设计.............................................................................. 2
2.1拨叉的工艺分析 ..................................................................................................................... 2 2.2拨叉的工艺要求 ..................................................................................................................... 2 2.3工艺规程设计 ......................................................................................................................... 3 2.3.1确各表面加工方案 .............................................................................................................. 3 2.3.1.（1）影加工方法的因素 ................................................................................................ 3 2.3.1.(2) 加工方案的选择 ....................................................................................................... 3 2.4 确定定位基准 ........................................................................................................................ 4 2.4.1粗基准的选择 .................................................................................................................. 4 2.4.2精基准选择的原则 .......................................................................................................... 4 2.5 拨叉加工工艺路线的拟订 .................................................................................................... 5 2.5.1工序的合理组合 .............................................................................................................. 5 2.5.2工序的集中与分散 .......................................................................................................... 6 2.5.3加工阶段的划分 .............................................................................................................. 7 2.5.4加工工艺路线方案的比较 .............................................................................................. 7 2.6拨叉的偏差，加工余量，工序尺寸及毛坯尺寸的确定 ................................................... 12 2.6.1毛坯的结构工艺要求 ........................................................................................................ 12 2.6.2拨叉的偏差计算 ................................................................................................................ 12 2.7确定切削用量及基本工时（机动时间） ........................................................................... 15 2.8时间定额计算及生产安排 ................................................................................................... 22
第3章 镗孔夹具设计................................................................................................ 24
3.1 定位、夹紧方案的选择 ...................................................................................................... 25 3.2切削力及夹紧力的计算 ....................................................................................................... 26 3.3 误差分析与计算 ................................................................................................................. 27 3.4 夹具材料的研究 .................................................................................................................. 28 3.5 夹具零、部件的设计与选用 .............................................................................................. 28 3.5.1定位销选用 .................................................................................................................... 28 3.5.2夹紧装置的选用 ................................................................................................................ 28
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继续教育学院专科生毕业设计(论文) 3.6 夹具设计及操作的简要说明 .............................................................................................. 29
第4章 结 论....................................................................................................... - 30 - 参考文献................................................................................................................. - 31 - 致 谢................................................................................................................... - 32 -2
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