毕业毕业设计论文-拨叉(09.12.25)加工工艺及夹具设计 - 图文

河南机电高等专科学校毕业设计

拨叉（10.12.25）加工 工艺及夹具设计

学生姓名： 李仙仙 学生学号 090219129 年级专业： 09级机电一体化 指导教师： 杨富超

二〇一零年十二月

摘 要

此次设计是对拨叉零件的加工工艺和夹具设计，其零件为锻件，具有体积小，零件复杂的特点，由于面比孔易加工，在制定工艺规程时，就先加工面，再以面为基准来加工其它，其中各工序夹具都采用专用夹具，特别的对于加工大头孔、槽和钻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。

关键词 拨叉，加工工艺，专用夹具，设计

I

目 录

摘 要 ························· I 绪论．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．． 第1章 拨叉的分析 ···················· 2

1.1拨叉的工艺分析 ········································································································ 2 1.2拨叉的工艺要求 ········································································································ 2

第2章 工艺规程设计 ··················· 5

2.1 加工工艺过程 ··········································································································· 5 2.2确定各表面加工方案 ································································································ 6 2.2.1影响加工方法的因素 ····························································································· 6 2.2.2加工方案的选择 ···································································································· 6 2.3 确定定位基准 ·········································································································· 6 2.3.1粗基准的选择 ········································································································ 6 2.3.2精基准选择的原则································································································· 7 2.4 工艺路线的拟订 ······································································································· 7 2.4.1工序的合理组合 ···································································································· 8 2.4.2工序的集中与分散································································································· 8 2.4.3加工阶段的划分 ···································································································· 9 2.4.4加工工艺路线方案的比较 ···················································································· 10 2.5 拨叉的偏差，加工余量，工序尺寸及毛坯尺寸的确定 ········································· 11 2.5.1毛坯的结构工艺要求 ···························································································· 11 2.5.2拨叉的偏差计算 ··································································································· 12 2.6确定切削用量及基本工时（机动时间） ································································· 13 2.7时间定额计算及生产安排 ························································································ 20

第3章 镗孔夹具设计 ·················· 24

3.1 研究原始质料 ·········································································································· 24 3.2 定位、夹紧方案的选择 ··························································································· 24 3.3切削力及夹紧力的计算···························································································· 24 3.4 误差分析与计算 ······································································································ 26

1

3.5 零、部件的设计与选用 ··························································································· 26 3.5.1定位销选用 ··········································································································· 26 3.5.2夹紧装置的选用 ··································································································· 26 3.6夹具设计及操作的简要说明 ···················································································· 28

第4章 铣槽夹具设计 ·················· 28

4.1研究原始质料 ··········································································································· 28 4.2定位基准的选择 ······································································································· 28 4.3 切削力及夹紧分析计算 ··························································································· 28 4.4 误差分析与计算 ······································································································ 29 4.5零、部件的设计与选用···························································································· 30 4.5.1定位销选用 ··········································································································· 30 4.5.2夹紧装置的选用 ··································································································· 30 4.5.3 定向键与对刀装置设计 ······················································································· 33 4.6 夹具设计及操作的简要说明 ··················································································· 33

第5章 钻孔夹具设计 ·················· 34

5.1研究原始质料 ··········································································································· 34 5.2定位基准的选择 ······································································································· 34 5.3切削力及夹紧力的计算···························································································· 34 5.4误差分析与计算 ······································································································· 35 5.5 零、部件的设计与选用 ··························································································· 36 5.5.1定位销选用 ··········································································································· 36 5.5.2夹紧装置的选用 ··································································································· 37 5.5.3 钻套、衬套、钻模板设计与选用 ········································································ 37 5.6夹具设计及操作的简要说明 ···················································································· 38

结 论 ························ 39 参考文献 ······················· 40

2