毕业论文 数控铣床的零件加工及夹具设计.doc

毕业论文 数控铣床的零件加工及夹具设计


                       
摘要：随着社会生产和科学技术的不断进步，各类工业新产品层出不穷。机械制造产业作为国民工业的基础，其产品更是日趋精密复杂特别是在宇航、航海、军事等领域所需的机械零件，精度要求更高，形状更为复杂且往往批量较小，加工这类产品需要经常改装或调整设备，普通机床或专业程度高的自动化机床显然无法适应这些要求。同时，随着市场竞争的日益加剧，企业生产也迫切需要进一步提高其生产效率，提高产品质量及降低生产成本。在这种背景下，一种新型的生产设备——数控机床就应运而生了，它综合应用了电子计算机、自动控制、伺服驱动、精密测量及新型机械结构等多方面的技术成果，形成了今后机械工业的基础及机械制造工业的发展方向。随着数控机床的发展与普及，现代化企业对于懂得数控加工技术、能进行数控加工编程的技术人才的需求量必将不断增加。数控车床是目前使用最广泛的数控机床之。
在机械加工中，为完成需要的加工工序，装配工序及检验工序等，首先要将工件固定，使之占有确定的位置，这种保证一批工件占有确定位置的装置，统称夹具。为保证工件的加工质量，提高加工效率，降低生产成本，改善劳动条件，扩大机床使用范围，缩短新产品试制周期。专用夹具应用越来越广泛。
 本文对零件加工和夹具设计主要有以下几点内容：
1.根据毕业设计任务书中的要求和已知的条件对零件进行分析。
2.对零件进行手工绘图
3.分析零件的加工部位，制定工艺路线，填写工艺卡片和工序卡片。
4.对零件某道工序进行夹具设计
5.选择合适的机床，确定定位夹紧的方案
6.用AUTO CAD2007进行装配图和零件图的绘制。
关键词：零件分析，手工绘图，工艺制定，夹具设计，计算机辅助绘图。
 
Abstract: along with the social production and the improvement of science and technology, all kinds of industrial new product emerge in endlessly. Mechanical manufacturing industry as the national industrial base, its product is increasingly sophisticated especially in space, navigation, military etc required mechanical parts, higher accuracy, shape is more complex and often batch is lesser, processing this kind of product need often modified or adjust the equipment, ordinary machine or professional degree high automation tool obviously can't adapt to these requirements. At the same time, along with the growing market competition, enterprise production also urgently need to further improve the production efficiency, improve product quality and reduce production costs. In this context, a new type of production equipment - CNC machine is made, it comprehensive application of electronic computers, automatic control, servo drive, precision measurement and new mechanical structure of various technical achievement, formed the basis of mechanical industry in the future and the mechanical manufacturing industry development direction. With the development and popularization of nc machine tools, modern enterprise to know nc machining technology, can the nc programming technology talent demand will continue to increase. Nc lathe is currently the most widely used of nc machine.
In mechanical processing, in order to perform required processing working procedure, assembly process and inspection process, first to the workpiece, which determine the fixed position of possession, this guarantee batch of workpiece position device, occupies determine collectively fixture. To ensure the process quality and improve workpiece machining efficiency, reduce production cost, improve working conditions, and expand machine tool use scope, shorten new product trial period. Special jig used more widely.
This paper parts processing and fixture design mainly have the following contents:
1. According to the requirements of the graduation design specification and known conditions on the parts for analysis.
2. The parts manual drawing
3. Analysis parts processing parts, formulate the process route, fill in process card and process card.
4. A procedure of parts for fixture design
5. Choose the right tools, sure positioning clamping schemes
6. CAD2007 with AUTO spare parts and on the assembly drawing.
Keywords: parts analysis, manual drawing, technology formulating and fixture design, computer aided drawing.
 
目录
一 绪论
 1.1本课题的任务……………………………………………
  1.2 本课题研究的重点和意义………………………………
二 零件的分析
 2.1零件的材料分析……………………………..
  2.2 零件的工艺分析…………………
2.3 零件的毛坯选择………………………..
三 工艺规程的设计
 3.1确定毛坯的铸造方法和热处理……………
  3.2基准的选择……………………………
3.2.1粗基准的选择原则……………………
3.2.2 精基准的选择原则………………
  3.3 制定工艺路线………………………
  3.4刀具的选择和刀具卡片……………
  3.5机械加工余量、工序尺寸及毛培尺寸的确定……………
  3.6机床和量具……………………………..
3.6.1机床的发展趋势……………………
     3.6.2 量具的选择………………………
  3.7 确定切削用量及工序卡片…………………
3.7.1 粗加工切削用量的选择原则…………………
3.7.2 精加工切削用量的选择原则…………………
3.7.3 工时定额的确定（单件时间定额）………
3.7.4 确定切削用量及基本工时………………
四 夹具设计
  4.1. 夹具的分类………….
   4.2专用夹具的设计方法和步骤………………
  4.3夹具方案设计和初步理念…………….
   4.4 定位机构的设计及误差分析………………………
      4.4.1 定位基准的选择………………………
       4.4.2 确定定位元件，计算定位误差………….
       4.4.3 定位销的选择和计算………………
       4.4.4定位误差的分析与计算…………
  4.5夹紧机构的确定………………………
     4.5.1夹紧元件的选择与夹紧力的计算……………
      4.5.2夹紧元件的强度校核……………………
   4.6 非标准零件的设计………………..
  4.7 夹具技术的发展……………………………
     4.7.1柔性夹具的研究和发展……………
       4.7.2计算机辅助夹具设计(CAFD)）…………
       4.7.3自动化夹具（AFD）……………………….
五.附页
 5.1 数控加工工艺卡片………………………………
  5.2 数控加工工序卡片………………………………..
六.设计总结……………………………………………
七.致谢…………………………………………….
八.参考文献…………………………………………