机械5

摘要 夹具是零件加工的夹紧装置，是加工零件的一种必不可少的装置。夹具利用率高，经济性好，对功能组件的使用和数量少。随着零件的尺寸变化，越来越多的夹具被淘汰了，因此，设计一套专用夹具是十分有必要的。在设计专用夹具时要考虑工件的定位方案，工件的夹紧方案和设计夹紧机构，夹具的其他组成部分，夹具的结构形式等。 此次设计是对箱体机械加工工艺及夹具设计，其零件为铸件，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，本次设计镗床夹具夹具。 设计之初我查阅相关数据及国内外关于机床夹具的文献，在看懂零件图的同时对零件的结构和工艺进行分析，明确粗基准和精基准的选择，确定零件的加工余量与毛坯的尺寸、从而确定零件的加工工艺过程、计算各工序的切削用量及工时。最终完成了本次设计所需的夹具。 关键词：箱体、机械加工、工艺、镗床夹具 ABSTRACT Fixture is the clampi
ng device of parts processi
ng, is a
n esse
ntial device for processi
ng parts. Low cost a
nd high usage of the fixture. With the size cha
nge of parts, more a
nd more fixtures are elimi
nated. Therefore, it is
necessary to desig
n a special fixture. I
n the desig
n of the special fixture, the positio
ni
ng scheme of theworkpiece, the clampi
ng scheme of theworkpiece a
nd the desig
n of the clampi
ng mecha
nism, other compo
ne
nts of the fixture a
nd the structural form of the fixture should be co
nsidered. This desig
n is for the box machi
ni
ng process a
nd fixture desig
n, its parts are casti
ngs, parts are complex characteristics, because the surface is easier to process tha
n the hole, i
n the formulatio
n of the process specificatio
n, the surface is first processed, a
nd the
n the surface is used as the be
nchmark to process other, i
nwhich each process fixture uses special fixture, this desig
n bori
ng machi
ne fixture. At the begi
n
ni
ng of the desig
n, I co
nsulted the releva
nt data a
nd domestic a
nd foreig
n literature o
n machi
ne tools a
nd fixtures. While u
ndersta
ndi
ng the part drawi
ngs, I a
nalyzed the structure a
nd process of the parts, made clear the selectio
n of rough a
nd fi
ne datum, determi
ned the machi
ni
ng allowa
nce a
nd bla
nk size of the parts, so as to determi
ne the processi
ng process of the parts, calculate the cutti
ng amou
nt a
ndworki
ng hours of each process. Fi
nally, the fixture required for this desig
n is completed. Keywords: box, machi
ni
ng, tech
nology, bori
ng machi
ne fixture 目录 摘要I ABSTRACT II 1绪论1 1.1工艺过程1 1.2机械加工工艺规程2 1.3机械加工的生产率及技术经济分析3 1.4机床夹具的概述4 1.5机床夹具的组成及分类5 1.6机床夹具在机械加工中的作用6 1.6夹具设计的特点和基本要求6 2零件的分析及生产类型的确定7 2.1零件的作用7 2.2零件的分析7 2.2.1零件的组成表面7 2.2.2零件的技术要求8 2.2.3零件的形位公差8 2.3零件生产类型的确定8 3零件毛坯的设计9 3.1确定零件的材料及制造方式9 3.2选择加工的定位基准9 3.3确定毛坯尺寸公差与机械加工余量10 4零件的加工工艺设计14 4.1主要加工工序的安排14 4.2加工工艺路线的制定14 4.3加工方法、加工刀具及量具的选用16 4.4确定切削用量及基本工时19 5镗削Ф45、Ф32孔专用夹具设计32 5.1确定定位方案、定位元件32 5.1.1确定定位方案32 5.1.2确定定位元件32 5.2确定夹紧方案、夹紧元件33 5.2.1确定夹紧方案33 5.2.2确定夹紧元件33 5.3确定夹具体33 5.4确定导向装置33 5.5镗削力计算33 5.6定位误差分析34 5.7加工精度误差分析35 结论36 致谢37 参考文献38