机械5

杠杆的工艺规程及拉大孔六边形夹具设计 摘要 本次设计内容涉及了机械制造工艺及机床夹具设计、金属切削机床、公差配合与测量等多方面的知识。本设计是杠杆零件的加工工艺规程及一些工序的专用夹具设计。杠杆零件的主要加工表面是平面及孔。一般来说，保证平面的加工精度要比保证孔的加工精度容易。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的加工精度。基准的选择以杠杆外圆面作为粗基准，以孔及其下表面作为精基准。先将底面加工出来，然后作为定位基准，在以底面作为精基准加工孔。整个加工过程选用组合机床。在夹具方面选用专用夹具。考虑到零件的结构尺寸简单，夹紧方式多采用手动夹紧，夹紧简单，机构设计简单，且能满足设计要求。 关键词杠杆零件，加工工艺，夹具，定位，夹紧 ABSTRCT This desig
n co
nte
nt has i
nvolved the machi
ne ma
nufacture craft a
nd the e
ngi
ne bed jig desig
n, the metal-cutti
ng machi
ne tool, the commo
n differe
nce coordi
natio
n a
nd the survey a
nd so o
n thevarious k
nowledge.This paper is to desig
n the craft processes of maki
ng the lever spare parts a
nd some specialized to
ngs i
n the process. The lever spare part primarily processes the surface a
nd bores. Ge
nerally speaki
ng, to guara
ntee the accuracy of the flat surface process is easier tha
n that of the bore. Therefore, this desig
n follows the pri
nciple that surface first a
nd the
n the bore, a
nd defi
nitely divides the process of flat surface a
nd bore i
nto coarse processes a
nd precise processes to guara
ntee the bore processes. The basic choice is to outside circle as rough basis a
nd to bore a
nd its
next surface as precise basis. The bottom is first processed out to be fixed positio
n basis, a
nd process the bore usi
ng the bottom as the precise basis. Thewhole processes choose the machi
ne bed. I
n the aspects of to
ngs choosi
ng, specialized to
ngs are used. I
n co
nsideratio
n of the simple co
nstructio
n size of the spare parts, clippi
ng by ha
nds is adopted. It is simple, a
nd the orga
nizatio
n desig
n is simple, a
nd ca
n satisfy the desig
n request. Key Words Lever spare parts, craft proces, to
ngs, fixed positio
n, tight clip 目录 序言1 一零件的分析2 1.1零件的作用2 1.2零件的工艺分析2 二.毛坯的确定4 2.1确定毛坯的制造形式4 2.2毛坯形状及尺寸5 三拟定加工工艺路线7 3.1基准的选择7 3.1.2粗基准选择7 3.1.2精基准的选择8 3.2制定工艺路线9 四零件加工工序设计12 4.1工序1设计12 4.2工序2设计12 4.3工序3设计12 4.4工序4设计14 4.5工序5设计16 4.6工序6设计18 4.7工序7设计22 4.8工序8设计24 4.9工序9设计27 4.10工序10设计29 五夹具设计33 5.1问题的提出33 5.2定位基准的选择33 5.3工件定位的基本原理35 5.4常见定位方式及定位元件37 5.5切削力及夹紧力计算40 5.6定位误差分析43 5.7夹具设计及操作简要说明43 总结45 致谢47 参考文献48