攀枝花学院本科毕业设计（论文）
解放汽车第二轴后球轴承盖
加工工艺及夹具设计
学生姓名： 吉杨 学生学号： 200410627013 院（系）： 机电工程学院 年级专业： 2004级机械制造及其自动化4班 指导教师： 陈广凌 副教授
二〇〇八年六月
攀枝花学院本科毕业设计（论文） 摘要
摘要
本设计是汽车变速箱箱体轴承盖零件的加工工艺规程及一些工序的专用夹具设计。汽车变速箱箱体端盖零件的主要加工表面是平面及孔系。一般来说，保证平面的加工精度要比保证孔系的加工精度容易。因此，本设计遵循先面后孔的原则。并将孔与平面的加工明确划分成粗加工和精加工阶段以保证孔系加工精度。基准选择以变速箱轴承盖的右端面内孔作为粗基准，以左端面内孔作为精基准。主要加工工序安排是先以右端面内孔定位加工出左端面及其内孔，再以左端面与四个联结孔中的任意一个a孔定位加工出其他部位。在后续工序中全部由左端面及其内孔与a孔定位。整个加工过程均选用组合机床。夹具选用专用夹具，夹紧方式多选用气动夹紧，夹紧可靠，机构可以不必自锁。因此生产效率较高。适用于大批量、流水线上加工。能够满足设计要求。
关键词：轴承盖，加工工艺，专用夹具
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攀枝花学院本科毕业设计（论文） ABSTRACT
ABSTRACT
The design of the automobile transmission parts covered box bearing the processing of order and some special fixture design process. Box car gearbox cover parts of the main processing surface is flat and holes. In general, guarantee the accuracy of processing than the flat-guarantee the accuracy of the processing easier. Therefore, the design followed after the first hole of the principle. And the hole with the plane clearly divided into rough machining processing and finishing stages of processing to ensure the accuracy of the hole. Benchmark gearbox bearing caps to choose the right end of the hole as a rough benchmark, the extreme left of the hole to fine as the benchmark. Main processing arrangement is within the first face-to the far right to extreme left-positioning and processing within the hole, and then to extreme left side and a hole location to other parts of the processing. In follow-up processes by the extreme left side and all the holes and a hole location. The entire process are optional combination of machine tools. Fixture optional dedicated fixture, clamping means more choice of pneumatic clamping, clamping reliable, agencies can not self-locking. So production more efficient. Applicable to high-volume, on the processing line. To meet the design requirements.
Key words: Bearing Cap; machining technology; special-purpose clamping apparatus
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攀枝花学院本科毕业设计（论文） 目录
目 录
摘要···································································································································· I ABSTRACT ····················································································································· II
1 绪论····························································································································· 2
1.1课题背景 ............................................................................................................... 2
1.2箱体加工现状 ........................................................................................................ 2
2 零件的分析················································································································· 4
2.1零件的作用 ............................................................................................................ 4
2.2零件的工艺分析 ..................................................................................................... 4 2.3轴承盖加工的安排 ................................................................................................. 5
2.3.1孔和平面的加工顺序 ................................................................................... 5 2.3.2孔系加工方案选择 ....................................................................................... 5
3 定位基准的选择 ········································································································ 7 3.1粗基准的选择 ........................................................................................................ 7 3.2精基准的选择 ........................................................................................................ 7 4 汽车轴承盖主要加工工序 ························································································ 8
4.1轴承盖加工工序分析 .............................................................................................. 8 4.2制定工艺路线 ........................................................................................................ 8 5 确定机械加工余量 ···································································································10
5.1底面的加工余量。 ................................................................................................10
5.2孔?60?0.2mm的加工余量 .....................................................................................10 5.3 3x?10.8mm孔与a孔?10.8?0.02mm的加工余量................................................... 11 5.4 ?8?0.058mm孔与孔?24?0.045mm的加工余量 ........................................................ 11 5.5圆柱面上孔加工余量 ............................................................................................. 11 5.6底面支承孔加工余量 .............................................................................................12
5.6.1粗车 ...........................................................................................................12 5.6.2精车 ...........................................................................................................12 5.6.3铸件毛坯的基本尺寸 ..................................................................................12
6 确定切削用量及机动时间 ·······················································································13
6.1车T2端面，粗车?120mm，?126.5mm，精车?120mm，?126.5mm孔 ...........13 6.2粗车?59mm孔和端面 ..........................................................................................16 6.3钻孔3??10.8mm孔，扩a孔，铰a孔 .................................................................18 6.4精车右端面孔至?60?0.2mm..................................................................................20
6.5粗车螺纹，精车螺纹 .............................................................................................20
6.6钻孔?21mm，钻孔?5mm ...................................................................................22 6.7锪平面 ..................................................................................................................23 6.8攻螺纹M6-2 ..........................................................................................................24 6.9粗镗孔?23mm.....................................................................................................24 6.10精镗孔?24?0.045mm ...........................................................................................25
0.0586.11钻孔?7.8mm，铰孔至?8mm，锪?20mm孔 ..............................................25
6.12检查....................................................................................................................27 7 工时定额计算 ···········································································································28
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攀枝花学院本科毕业设计（论文） 目录
7.1车T2端面，粗车?120mm，?126.5mm，精车?120mm，?126.5mm孔 ...........28 7.2粗车?59mm孔和端面 ..........................................................................................29 7.3钻孔3??10.8mm孔，扩a孔，铰a孔.................................................................29 7.4精车右端面孔至?60?0.2mm..................................................................................29 7.5粗车螺纹，精车螺纹 .............................................................................................30 7.6钻孔?21mm，钻孔?5mm ...................................................................................30 7.7锪平面 ..................................................................................................................31 7.8攻螺纹M6-2 ..........................................................................................................31 7.9粗镗孔?23mm.....................................................................................................31 7.10精镗孔?24?0.045mm ...........................................................................................32 7.11钻孔?7.8mm，铰孔至?80.058mm，锪?20mm孔 ..............................................32
8 专用夹具设计 ···········································································································33
8.1钻4×Φ10.8孔夹具设计......................................................................................33
8.1.1定位基准的选择 .........................................................................................33 8.1.2切削力的计算与夹紧力分析 ........................................................................33 8.1.3夹紧装置及夹具体的设计 ...........................................................................34 8.1.4夹具精度分析 .............................................................................................35 8.1.5钻套的选择 ................................................................................................35 8.1.6夹具设计及操作的简要说明 ........................................................................36 8.2 钻?21孔夹具设计 ...............................................................................................36 8.2.1定位基准的选择 .........................................................................................36 8.2.2定位元件的设计 .........................................................................................36 8.2.3夹具体的设计 .............................................................................................37 8.2.4切削力及夹紧力计算 ..................................................................................38 8.2.5夹紧元件及辅助装置确定 ...........................................................................39 8.2.6 钻套和衬套的选择 .....................................................................................40 8.2.7定位误差分析 .............................................................................................40 8.2.8夹具操作的简要说明 ..................................................................................41
参 考 文 献····················································································································42
致 谢······························································································································43