毕业设计---副变速拨叉加工工艺编制及工装夹具数字化设计.doc

摘 要 本毕业设计的题目是副变速拨叉加工工艺编制及工装夹具数字化设计，本次的毕业设计论文分成两大部分： 第一部分主要是副变速拨叉的工艺规程设计。其中包括采用CAD绘制零件图、设计加工工艺、绘制加工工艺卡片和加工工艺规程卡。其主要内容是：了解零件的作用，确定生产类型，零件的工艺性分析，确定毛坯制造形式，制定工艺路线（选择各种面的加工方法，确定加工的粗基准和各个加工面加工的精基准，拟定各个面的加工路线、安排工序顺序，安排辅助工序），选择机床及工艺设备，确定机械加工余量、各工序的加工余量、工序尺寸和尺寸公差，确定各个工序的定位、夹紧方案，计算每道工序的切削用量和基本工时。 第二部分主要是两道工序的夹具设计。在这一部分的内容中，主要包括确定定位、夹紧方案，该工序定位元件的选择，确定定位基准，设计夹紧机构，合理安排夹具方向、手柄方位来方便工人操作，计算切削力及所需夹紧力，校核夹紧力是否满足要求，计算定位误差及验证定位方案的合理性。 关键词：副变速拨叉 工艺设计 夹具设计 ABSTRACT The graduation project is titled preparing the machining process of the subtransmission fork and the fixture of digital design, this design graduate thesis is divided into two parts: The first part is mainly the machining process planning of subtransmission fork . It includes the use of CAD drawing parts drawing, design machining process, drawing machining processing cards and process planning cards. Its main contents are: Understanding the function of parts,determining the type of production, analysing the manufacture technics of parts, determining the form of manufacturing the blank , formulation process route (choose processing methods of a variety of surfaces, determine the crude datums of processing and machining precision datums of various machined surfaces, draw up the processing route of various machined surfaces, arrange the order of processing steps and auxiliary processing steps), select the machine and processing equipment, determine the machining allowance and each processing surface allowances and processing dimensions and dimensional tolerances, determine the program of positioning and clamping the workpiece at various processing steps, calculate the cutting conditions of each processing steps and the basic task time. The second part is mainly fixture design of two processing steps . In this part of the content, including determining positioning and clamping scheme,select the positioning component of the processing step, determine the positioning datums, design clamping mechanism, reasonable arran