发动机曲轴工艺设计及其中两道工序的夹具设计毕业论文

1、发动机曲轴工艺设计及其中两道工序的夹具设计摘 要本文主要介绍了发动机曲轴工艺设计及其中两道工序的夹具设计。本文作者是在保证产品质量、提高生产率、降低成本、充分利用现有生产条件、保证工人具有良好而安全劳动条件的前提下进行设计的。在工艺设计中，作者结合实际进行理论设计，对曲轴传统生产工艺进行了改进，优化了工艺过程和工艺装备，使曲轴的生产加工更经济、合理。在夹具设计部分，作者在收集加工所用机床、刀具及辅助工具等有关资料后，对工件材料、结构特点、技术要求及工艺分析的基础上，按照夹具设计步骤设计出符合曲轴生产工艺及夹具制造要求的夹具。关键词：发动机 曲轴 工艺 夹具AbstractThis text i

2、ntroduce engine crankshaft technological design and two of them jig of process design mainly. The author of this text is guaranteeing product quality, boost productivity, lower costs, utilize existing working condition, guaranteeing worker to have good work prerequisite of terms to design . In techn

3、ological design, the author combine carrying on theory design, improve the traditional production technology of the crankshaft actually, optimize craft course and craft equip, enable economy rational even more of production and processing of the crankshaft. Designing in the jig , the author collect

4、the relevant materials, such as lathe, cutter and handling tool，etc. At the foundation of the analyse of work piece material, specification requirement and craft, and make jig of request according to jig measure design and cankshaft production technology and jig.目 录 TOC o 1-3 h z u HYPERLINK l _Toc2

5、61722996 摘 要1 HYPERLINK l _Toc261722997 Abstract2 HYPERLINK l _Toc261722998 第1章 绪论 水平分力： QUOTE 垂直分力： QUOTE 在计算切削力时，必须考虑安全系数，安全系数 QUOTE 基本安全系数， QUOTE QUOTE 加工性质系数， QUOTE QUOTE 刀具钝化系数， QUOTE QUOTE 断续切削系数， QUOTE 因此， QUOTE 按照夹具设计原则合理确定夹紧力的作用点和作用方向，即应计算夹紧力的大小。计算夹紧力是很复杂的问题，一般只能粗略的估计。因为在夹紧过程中，工件受到切削力、重力、冲击

6、力、离心力和惯性力等的作用，从理论上讲，夹紧力的作用必须与上述作用力（矩）平衡。但是在不同条件下，上述作用力在平衡系中对工件所起的作用是各不相同的。为了简化夹紧力的计算，通常假设工艺系统是刚性的，切削过程是稳定的，在这些假设条件下，根据切削力试验计算公式求出切削力，然后找出加工过程中最不利的瞬时状态，按静力学原理求出夹紧力的大小。夹紧力大小的计算通常表现为夹紧力矩与摩擦力矩的平衡。夹紧力的计算公式： QUOTE 式中 QUOTE 在最不利条件下由静力学平衡计算求出夹紧力； QUOTE 实际需要的夹紧力；安全系数，一般取 QUOTE QUOTE 。粗加工取大值，精加工取小值。本夹具采用螺旋联动夹

7、紧，增力比公式为：扳手长 QUOTE 螺纹中径螺纹升角 QUOTE 螺纹摩擦角由螺纹直径12及手柄长200mm（ QUOTE 、 QUOTE 可查到）求得：为克服水平切削力，实际夹紧力N应为式中， QUOTE 和 QUOTE 为夹具定位表面及夹紧表面上的摩擦系数， QUOTE ，螺杆作用力为：因此本夹具安全可靠。4.1.5夹具精度分析夹具放在机床上必然会有一定的夹具定位误差，所谓的定位误差是由于定位不准造成的某工件在工序尺寸（通常是指加工表面对工序基准的距离尺寸）或位置度要求表面的加工误差。夹具的定位误差通常包括两方面：夹具各元件之间的位置误差；夹具中各定位元件的磨损。曲轴在定位时，主要依靠定

8、位支柱来定位，而定位支柱在定为过程中又包括两部分配合，衬套2和夹具体的配合 QUOTE 和衬套2与定位支柱的配合 QUOTE QUOTE 。定为误差关键就在这两部分的配合公差。 QUOTE 的公差为 QUOTE QUOTE 的公差为 QUOTE 则，其公差为 QUOTE ； QUOTE 的公差为 QUOTE QUOTE 的公差为 QUOTE 则，其公差为 QUOTE 所以其最大间隙为：通常，对某一定位方案，经分析计算其可能产生的定位误差，只要小于有关尺寸或位置公差的 QUOTE ，一般即认为定位方案能满足该工序的加工要求。而曲轴在该夹具上的允许误差为 QUOTE ，因此，该夹具定为满足要求。工

9、件在夹具中的位置是由定位元件确定的，当工件上的定位表面一旦与夹具上的定位元件相接触或相配合，作为一个整体的工件的位置也就确定了。当对于一批工件来说，由于在各个工件的有关表面之间，彼此在尺寸及位置上均有着在公差范围内的差异，但每个被定位元件的某些表面都会有自己的位置变动量，从而造成在工序尺寸和位置要求上的加工误差。该零件在本工序的精度要求为自由公差，而本工序的主要定位面主轴颈3，尺寸精度要求也为自由公差，根据经验，其对加工误差的影响在要求范围内。4.1.6夹具设计及操作的简要说明如前所述，在设计夹具时首先着眼于定位精确，装卸方便。在定位过程中，由于主轴颈3及其主侧面已经粗磨过，已经达到较高的精度

10、（ QUOTE ），以其作为定位基准，以定位铁2作为定位部件，对其进行定位能够达到要求的定位精度（ QUOTE ）；再把它放在其工作平台垫铁1上，然后通过手柄与压板螺栓驱动压板推动曲轴向垫铁2移动并将其压紧。钻孔的过程是通过钻模板的定位，在衬套1内的衬套的导向作用下，采用6高速钢锥柄加长麻花钻对曲轴进行钻削，形成通孔，从而完成打直油孔工参考文献1 张洪波. HYPERLINK /kns50/detail.aspx?filename=2004126767.nh&dbname=CMFD2005&filetitle=4102%e7%b3%bb%e5%88%97%e6%9f%b4%e6%b2%b9%e

11、6%9c%ba%e6%9b%b2%e8%bd%b4%e8%ae%be%e8%ae%a1%e4%b8%8e%e5%b7%a5%e8%89%ba%e5%88%86%e6%9e%90 t _top 4102系列柴油机曲轴设计与工艺分析D. 天津大学, 2003. 2 李玉森. HYPERLINK /kns50/detail.aspx?filename=2004126446.nh&dbname=CMFD2005&filetitle=%e5%85%ad%e7%bc%b8%e6%9f%b4%e6%b2%b9%e6%9c%ba%e6%9b%b2%e8%bd%b4%e6%9c%ba%e6%a2%b0%e5%8

12、8%b6%e9%80%a0%e5%b7%a5%e8%89%ba%e7%a0%94%e7%a9%b6%e5%8f%8a%e5%ba%94%e7%94%a8 t _top 六缸柴油机曲轴机械制造工艺研究及应用D. 天津大学, 2003. 3 纪有君. HYPERLINK /kns50/detail.aspx?filename=2006166178.nh&dbname=CMFD2006&filetitle=%e4%b8%ad%e5%a4%a7%e5%8a%9f%e7%8e%87%e5%86%85%e7%87%83%e6%9c%ba%e6%9b%b2%e8%bd%b4%e5%88%b6%e9%80%a

13、0%e5%b7%a5%e8%89%ba%e6%8a%80%e6%9c%af%e7%a0%94%e7%a9%b6 t _top 中大功率内燃机曲轴制造工艺技术研究D. 山东大学, 2006. 4 孙丽. HYPERLINK /kns50/detail.aspx?filename=2005136684.nh&dbname=CMFD2005&filetitle=%e5%9f%ba%e4%ba%8ePro%2fE%e4%ba%8c%e6%ac%a1%e5%bc%80%e5%8f%91%e7%9a%84%e6%9b%b2%e8%bd%b4%e8%ae%be%e8%ae%a1%e7%b3%bb%e7%bb

14、%9f t _top 基于Pro/E二次开发的曲轴设计系统D. 东北林业大学, 2005. 5 蔡雪凌. HYPERLINK /kns50/detail.aspx?filename=2004126412.nh&dbname=CMFD2005&filetitle=%e9%ab%98%e7%b2%be%e5%ba%a6%e5%86%85%e7%87%83%e6%9c%ba%e6%b0%94%e7%bc%b8%e4%bd%93%e5%8f%8c%e8%bd%b4%e5%ad%94%e7%b2%be%e9%95%97%e7%bb%84%e5%90%88%e6%9c%ba%e5%ba%8a%e8%ae%

15、be%e8%ae%a1%e6%8e%a2%e8%ae%a8 t _top 高精度内燃机气缸体双轴孔精镗组合机床设计探讨D. 天津大学, 2002. 6 褚守云. HYPERLINK /kns50/detail.aspx?filename=2007153904.nh&dbname=CMFD2007&filetitle=16V280%e6%9b%b2%e8%bd%b4%e5%8a%a0%e5%b7%a5%e5%b7%a5%e8%89%ba%e7%a0%94%e7%a9%b6 t _top 16V280曲轴加工工艺研究D. 上海交通大学, 2007. 7 郭东国. HYPERLINK /kns50/

16、detail.aspx?filename=2004126636.nh&dbname=CMFD2005&filetitle=CY4112%e6%9f%b4%e6%b2%b9%e6%9c%ba%e6%9c%ba%e4%bd%93%e5%8a%a0%e5%b7%a5%e5%b7%a5%e8%89%ba%e7%9a%84%e8%ae%be%e8%ae%a1%e7%a0%94%e7%a9%b6 t _top CY4112柴油机机体加工工艺的设计研究D. 天津大学, 2003. 8 刘凤彬. HYPERLINK /kns50/detail.aspx?filename=2006053221.nh&dbnam

17、e=CMFD2006&filetitle=%e6%9f%b4%e6%b2%b9%e6%9c%ba%e6%9c%ba%e4%bd%93%e7%bc%b8%e5%ad%94%e5%8f%8a%e7%bc%b8%e5%a5%97%e5%ad%94%e5%8a%a0%e5%b7%a5%e8%b4%a8%e9%87%8f%e9%97%ae%e9%a2%98%e6%8e%a2%e8%ae%a8 t _top 柴油机机体缸孔及缸套孔加工质量问题探讨D. 天津大学, 2005. 9 孔江波. HYPERLINK /kns50/detail.aspx?filename=2006053220.nh&dbname=

18、CMFD2006&filetitle=CYQD32%e6%9f%b4%e6%b2%b9%e6%9c%ba%e6%9c%ba%e4%bd%93%e5%8a%a0%e5%b7%a5%e7%ba%bf%e7%9a%84%e8%ae%be%e8%ae%a1%e4%b8%8e%e5%ae%9e%e6%96%bd t _top CYQD32柴油机机体加工线的设计与实施D. 天津大学, 2005. 10 谭达辉. HYPERLINK /kns50/detail.aspx?filename=2006023665.nh&dbname=CMFD2006&filetitle=YC6105ZLQ%e6%9f%b4%e

19、6%b2%b9%e6%9c%ba%e6%9b%b2%e8%bd%b4%e5%89%8d%e7%ab%af%e7%bb%93%e6%9e%84%e7%a0%94%e7%a9%b6 t _top YC6105ZLQ柴油机曲轴前端结构研究D. 吉林大学, 2005.11 杨宝田. HYPERLINK /kns50/detail.aspx?dbname=CMFD2005&filename=2004125933.nh&filetitle=4D%e5%9e%8b%e6%9f%b4%e6%b2%b9%e6%9c%ba%e6%9b%b2%e8%bd%b4%e5%8a%a0%e5%b7%a5%e5%b7%a5%

20、e8%89%ba%e8%ae%be%e8%ae%a1 4D型柴油机曲轴加工工艺设计D. 天津大学,200412 孙文亮. HYPERLINK /kns50/detailref.aspx?filename=2005013463.nh&dbname=CMFD2005&filetitle=%e6%9f%b4%e6%b2%b9%e6%9c%ba%e9%9b%b6%e9%83%a8%e4%bb%b6%e5%8e%bb%e6%af%9b%e5%88%ba%e6%8a%80%e6%9c%af%e7%a0%94%e7%a9%b6 t _top 柴油机零部件去毛刺技术研究D吉林大学, 2004. 13 陆俊利.

21、 HYPERLINK /kns50/detailref.aspx?filename=2006132896.nh&dbname=CMFD2006&filetitle=%e6%9c%ba%e5%ba%8a%e4%b8%bb%e4%bc%a0%e5%8a%a8%e7%b3%bb%e7%bb%9f%e8%be%85%e5%8a%a9%e8%ae%be%e8%ae%a1 t _top 机床主传动系统辅助设计D哈尔滨工程大学, 2006. 14 刘凤彬. HYPERLINK /kns50/detail.aspx?dbname=CMFD2006&filename=2006053221.nh&filetitl

22、e=%e6%9f%b4%e6%b2%b9%e6%9c%ba%e6%9c%ba%e4%bd%93%e7%bc%b8%e5%ad%94%e5%8f%8a%e7%bc%b8%e5%a5%97%e5%ad%94%e5%8a%a0%e5%b7%a5%e8%b4%a8%e9%87%8f%e9%97%ae%e9%a2%98%e6%8e%a2%e8%ae%a8 柴油机机体缸孔及缸套孔加工质量问题探讨D. 天津大学,200515 孙云山. HYPERLINK /kns50/detail.aspx?dbname=CMFD2005&filename=2005031373.nh&filetitle=%e5%a4%a7

23、%e5%8a%9f%e7%8e%87%e6%9f%b4%e6%b2%b9%e6%9c%ba%e6%9b%b2%e8%bd%b4%e6%a0%91%e8%84%82%e7%a0%82%e9%93%b8%e9%80%a0%e5%b7%a5%e8%89%ba%e7%9a%84%e7%a0%94%e7%a9%b6 o 大功率柴油机曲轴树脂砂铸造工艺的研究 相似度 3% t _blank 大功率柴油机曲轴树脂砂铸造工艺的研究D. 南京理工大学, 200516 邓文英. 金属工艺学D. 高等教育出版社，200517 关文达. 汽车构造.吉林大学D，199918 纪名刚. 机械设计.西北工业大学，20011

24、9 陈小复. 连铸机械设备操作、维修及20常见故障处理与自动化控制实用手册.清华大学D.200120 机械工程手册委员会. 机械工程手册.2版.北京；国防工业大学出版社，199021 成大先.机械设计图册：第一卷.化学工业出版社，2000 总结曲轴是发动机中的关键零件之一，其材质大体分为两类：一是钢锻曲轴，二是球墨铸铁曲轴。由于采用铸造方法可获得较为理想的结构形状,从而减轻质量，且机加工余量随铸造工艺水平的提高而减小。球铁的切削性能良好，并和钢制曲轴一样可以进行各种热处理和表面强化处理，来提高曲轴的抗疲劳强度和耐磨性。而且球铁中的内摩擦所耗功比钢大，减小了工作时的扭转振动的振幅和应力，应力集中

25、也没有钢制曲轴来的敏感。所以球墨铸铁曲轴在国内外得到广泛采用。本次设计中曲轴的材质为球铁。目前，国内大部分专业厂家普遍采用普通机床和专用组合机床组成的流水线生产，生产效率、自动化程度较低。曲轴的关键技术项目仍与国外相差12个数量级。但我相信我们会赶上并超过国外曲轴热处理的关键技术是表面强化处理。一般均正火处理，为表面处理作好组织准备。表面强化处理一般采用感应淬火或氮化工艺，少数厂家还引进了圆角淬火技术和设备。球铁曲轴具有诸多优点，国内外广泛采用。但整体水平与国外还有相当差距，除生产规模小、管理落后外，主要差距仍是制造工艺的落后。借鉴国外的先进技术和工艺方法是提高我国曲轴制造水平的捷径。制定工艺

26、规程的思路是：收集和熟悉制定工艺规程的有关资料图样，进行零件的结构工艺性；确定毛坯的类型及制造方法；选择定位基准；拟定工艺路线；确定各工序的工序余量、工序尺寸及其公差；确定各工序的设备，刀具、夹具、量具和辅助工具；确定各工序的切削用量及时间定额；确定主要工序的技术要求及检验方法；进行技术经济分析，选择最佳方案；编制工艺文件。夹具设计的思路是：明确设计任务，收集设计资料；拟订夹具的结构方案、绘制结构草图；绘制夹具总装图。绘制夹具总装图的顺序和方法：用双点化线或红色笔绘出工件的轮廓外形和主要表面，并用网纹线表示出加工余量；视工件轮廓为透明体，分别绘出定位、导向、夹紧及其他元件或装置，最后绘制夹具体

27、，形成一个夹具整体；标注尺寸、公差与配合和技术要求；对零件进行编号，填写零件明细栏和标题栏；绘制夹具零件图。通过本次的毕业设计，使我能够对书本的知识做进一步的了解与学习，对资料的查询与合理的应用做了更深入的了解，本次进行电火花加工机的设计，对我们在大学期间所学的课程进行了实际的应用与综合的学习。致 谢随着这篇毕业论文的完成，我四年的大学生活也即将划上一个圆满的句号。回忆这四年生活的点点滴滴，从入学时对大学生活的无限憧憬到课堂上对各位老师学术学识的深沉沉湎，从奔波于教室图书馆的来去匆匆到业余生活的五彩缤纷，一切中的一切都是历历在目，让人倍感留恋，倍感珍惜。 四年大学的学习生活注定将成为我人生中的

28、一段重要旅程。四年来，我的师长、我的领导、我的同学给予我的关心和帮助，使我终身收益，我真心地感谢他们。 在本文的撰写过程中，李燕老师作为我的指导老师，他治学严谨，学识渊博，视野广阔，为我营造了一种良好的学术氛围。 在此特向李燕老师致以衷心的谢意！置身其间，耳濡目染，潜移默化，使我不仅接受了全新的思想观念，树立了明确的学术目标，领会了基本的思考方式，掌握了通用的研究方法，而且还明白了许多待人接物与为人处世的道理。其严以律己、宽以待人的崇高风范，朴实无华、平易近人的人格魅力，与无微不至、感人至深的人文关怀，令人如沐春风，倍感温馨。正是由于他在百忙之中多次审阅全文，对细节进行修改，并为本文的撰写提供

29、了许多中肯而且宝贵的意见，本文才得以成型。在这次毕业设计中也使我们的同学关系更进一步了，同学之间互相帮助，有什么不懂的大家在一起商量，听听不同的看法对我们更好的理解知识，所以在这里非常感谢帮助我的同学。 此外，本文参考了大量杂志期刊和专业丛书，由于参考期刊太多，不能一一注明，敬请原谅并向所有作者和刊物致以诚挚的谢意！由于本人水平有限，纰漏之处在所难免，恳请各位老师不吝赐教。外文翻译Crank the engine of development of processing technology trendsAfter entering the 21st century, the engine c

30、rankshaft manufacture process, tools in all aspects. Leadership for nearly half a century of many knives cutting process and manual process, due to the low and the poor flexible machining precision, is gradually from the stage of history. High-speed, high efficient compound processing technology and

31、 equipment quickly into the automobile and automobile parts manufacturing, high efficient compound processing technology in the crankshaft production process in a degree of application, and will be the inevitable developing trend.The crankshaft processing technology and equipment statusAt present, t

32、he domestic older crankshaft production by ordinary machine and the most special machine, production efficiency and automation is relatively low. Balancing device generally adopted the crankshaft lathe cutting knife shaft neck and neck connecting shaft, working procedure quality stability, easy to p

33、roduce large processing stress, difficult to achieve reasonable limits.but. Widely used as ordinary precision MQ8260 crankshaft grinding machine for the coarse grinding and fine grinding, polishing, grinding, usually by artificial operation, the processing quality instability, dimension tolerance.On

34、e of the main characteristics of old line is too common, processing equipment, ductile iron crankshaft assembly line has 35 to 40 sets of equipment. The author examines the domestic a crankshaft forging steel production, the neck and the milling spindles and nc precise neck connecting shaft neck and

35、 neck car after a number of processes to finishing processes. Grinding side So this line of more than 60 sets of equipment, product line, site turnaround occupied large area, the production efficiency is completely by multiple devices decomposition processes and allowance to improve.But todays car e

36、ngine crankshaft manufacture is facing the following problemsIt is based on the above situation, since the beginning of the 21st century, high-speed, high precision, high efficient compound processing technology and equipment in automobile crankshaft manufacture rapidly, production efficiency improv

37、ed, so the crankshaft production line production equipment engine number was reduced. The author once in a car engine crankshaft production line equipment, including heat treatment, surface strengthening) only 13 equipment, product line, short cycle of high efficiency, easy machining quality control

38、.The crankshaft compound machining technology developmentIn the late 1980s, Germany BOEHRINGER company and HELLER company developed perfect crankshaft car - car pulled machine, this process is turning process and crankshaft crankshaft wheeled craft perfect combination, high production efficiency and

39、 machining precision, good flexibility, high automation degree, in short time, especially for the sword of the crankshaft is heavy cutting groove, processing can be directly after the crankshaft jingmo, save the coarse grinding process. Therefore, the crankshaft car - car pull processing technology

40、is an international popular in balancing the crankshaft processing.In the mid 1990s appeared new CNC milling machine makes the crankshaft high-speed balancing process and the crankshaft on a new step. CNC milling and CNC within the crankshaft speed milling, internal and external crankshaft mill has

41、disadvantages: not easy to knife and cutting speed is low (usually less than 160m/min), the cutting time longer, more investment, circulation machine for a long time. And CNC milling speed, has the following advantages of the crankshaft, high speed cutting ($350m/min), cutting time is shorter, proce

42、ss cycle time is shorter, cutting force is lesser, low temperature workpiece, the tool life, high in fewer knife, machining accuracy is higher, flexible better. Therefore, CNC milling is outside the crankshaft high-speed balancing the development direction of the crankshaft. According to expert intr

43、oduction, crankshaft car, car, suitable for shaft neck is heavy cutting groove, the balance blocks side of the crankshaft; without processing But the milling process is not high axial have heavy cutting slots of the crankshaft. The milling machine for Germany BOEHRINGER company VDF 315 OM - 4 with t

44、he high-speed milling machine, it is specially designed for the German BOEHRINGER automobile engine crankshaft design and manufacture of CNC milling machine, the flexible application of workpiece and milling equipment for servo control technology, can a year-end clamping dont change the crankshaft r

45、otary center, and following the crankshaft connecting shaft neck milling. VDF 315 OM - 4 with high-speed milling and integration of the composite structure of bed, workpiece, electronic synchronization driver ends with dry cutting machining, high precision, high efficient cutting, This machine use 8

46、40D CNC control system, SIEMENS through input parts of basic parameters can be automatically generate processing procedure, can be processed in length and diameter of 4.5-700mm 380mm in all kinds of crankshaft connecting within its axis, 0.02 mm diameter error for.By comparison, balancing the popula

47、r process of crankshaft is: by car and main journal and high-speed milling process, the neck and the high speed milling speed servo tend to outside, adopt dry milling machining. Because the overseas such equipment, product processing cost price is expensive, some domestic tool manufacturers (e.g., q

48、inghai second machine manufacturing Co., LTD) successively developed nc crankshaft lathe, milling machine, high-speed nc crankshaft lathe, nc crankshaft car special machine.The crankshaft grinding precision CNC cylindrical grinder with domestic situation has quite common, product processing precisio

49、n has considerable improvement. To meet the increasing demands of the crankshaft, crankshaft grinding machining forward high requirements. In addition to modern crankshaft grinding machine with high static, dynamic stiffness and high machining accuracy, still require a high grinding efficiency and m

50、ore flexible. In recent years, the more the requirement of crankshaft grinding machine with stable machining precision of the crankshaft grinding machine, therefore, provided the process capability coefficient, which means 1.67 experiment.it Cp requirement of crankshaft grinding machine processing t

51、olerance than the crankshaft given half of tolerance. With modern drive and control technology, measurement and control (cubicborazin CBN grinding and advanced machine), the application of components for crankshaft grinding high-precision grinding efficiency, created conditions. As a kind of connect

52、ing with the grinding process neck. It reflects the comprehensive application of these new technologies specific results achieved. With this technology can significantly improve grinding crankshaft connecting the grinding efficiency, neck and flexible machining precision machining. On the neck for c

53、onnecting with the crankshaft grinding, with spindle rotation axis, neck for clamping down at once and for all the neck. Connecting grinding In grinding process, grinding head swinging into to realize reciprocating the eccentric, tracking the connecting rod neck for turning grinding. To realize the

54、X axis with grinding, but must have high dynamic performance, still must have enough, to ensure the tracking accuracy requirements of neck connecting shape tolerance. The application of CBN wheels is connecting with neck important condition of grinding. Due to the high resistance CBN wheels in the g

55、rinding process, the diameter of the grinding wheel is almost constant, a dressing grinding 600-800 can crank. CBN wheels can also adopts high grinding speed, in general can adopt the crankshaft grinding up to 120 140m/s grinding speed, high grinding efficiency. Fixture systemFixture first appeared

56、in the 18th century fixture later. Along with the science and technology unceasing progress, already from a fixture auxiliary tool development becomes a complete range of process equipment. 1 The machine tools fixtureThe international association for the study of the production of statistics shows t

57、hat in the present, and small batch production of workpiece varieties of workpiece species varieties has total 85%. Modern production requirements of products manufactured by enterprises, in order to adapt to the frequently update market demand and competition. However, general enterprises are still

58、 used the traditional special jig, usually in a medium production capacity of the plant, to have about 10,000 sets of even special jig, On the other hand, in many varieties of production enterprises, every 3 4 years will update 50 80% special jig and fixture actual wear only for 10-20%. Especially i

59、n recent years, nc machine tools and machining center, the group technology, flexible manufacturing systems (FMS) new processing technology, the application of the machine tools fixture to put forward new requirements as follows: 1) can be quickly and easily equipment production of new products, to

60、shorten the production preparation period, lower production cost, 2) can have a group of clamping workpiece similarity characteristics, 3) could be used for precision machining precision machine tool fixtures, 4) to be applicable to all kinds of modern manufacturing technology of the new type of mac