设计简介
摘 要
本次设计是汽车变速箱中变速叉零件的加工工艺规程及一些工序的专用夹具设计。此变速叉零件的结构较为复杂，其加工的地方主要是孔和平面。本设计先加工孔后加工面。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它们的加工精度。基准选择以变速叉右面的最大的平面作为粗基准，来加工中间的通孔，然后以此加工过的孔作为精基准。主要加工工序安排是先以中心孔定位加工出顶平面和右侧平面以及下面的大孔的两平面，再以中心孔定位加工出下端的大孔。加工时是用镗床镗孔。最后以这两个孔为基准，分别加工右侧的槽和顶面的螺纹底孔。整个加工过程选用了钻床、铣床和镗床。工件在机床上定位夹紧选用专用夹具，夹紧方式为手动夹紧，夹紧可靠，操作方便。因此生产效率较高，适用于中批量、流水线上加工。能够满足设计要求。
关键词: 加工工艺 定位 夹紧 专用夹具
Abstract
This design is a lather to become soon an appropriation for inside pulling out fork spare parts processing craft rules distance and some work prefaces tongs design.This pull out the construction of the fork spare parts than for complicacy, its the place that process is a peaceful in bore primarily.This design processes after processing first the bore.Process with flat surface the clear and definite dividing the line the bore the coarseness processes to process with the nicety the stage to guarantee their process the precise degree.The basis choice to pull out rough basis of conduct and actions of the biggest flat surface of the right in fork, process the in the center in general use bore, then be used as the precise basis with the bore that processed.Processing primarily work preface arrangement is first to process a flat surface with the center bore fixed position with the right side flat surface and below big bore of two flat surface, again with center bore the fixed position processes the big bore that carry down.While processing is to use the boring machine boring bore.Regard these two bores as the basis finally, process the right-hand slot respectively with the thread bottom bore of the a.Whole processes the process chose to use to the drill machine, miller with the boring machine .The tongs chooses to use the appropriation tongs, clipping tight way as to move to clip tight, clip tight and dependable, operation convenience.Therefore produce the efficiency higher, be applicable to the middle quantity measures, the flowing water is on-line to process.Can satisfy the design request.
Keywords Process the craft，Fixed position，Clip tight，Appropriation tongs
目录
摘 要......................................................... 1
Abstract..................................................... 2
1序言........................................................ 4
1.1机械制造工艺的目标......................................... 5
1.2工艺的任务................................................ 6
1.3工艺规程的基本要求......................................... 7
2.零件的分析.................................................. 9
2.1零件的作用................................................ 9
2.2零件的工艺分析............................................. 9
3工艺规程设计................................................ 10
3.1 加工工艺过程............................................. 10
3.2确定各表面加工方案........................................ 10
3.3确定毛坯的制造形式........................................ 11
3.4基面的选择............................................... 11
3.5工艺路线的拟定............................................ 13
3.6机械加工余量,工序尺寸及毛坯尺寸确定........................ 18
3.7确定切削用量及基本工时.................................... 20
4夹具设计................................................... 23
4.1钻床夹具设计（1）......................................... 23.
4.2钻床夹具设计（2）......................................... 27
5结论....................................................... 30
参考文献..................................................... 32
致谢......................................................... 33
