基于三维设计的系列专用夹具设计说明任务书

1、 PAGE62 / NUMPAGES71 毕业设计任务书专业 机械设计制造与其自动化 班级 091 下发日期 2013-03-01题目基于三维设计的系列专用夹具设计专题机床夹具设计主要容与要求本设计的目的：加工工艺的水平，从某种程度上来说决定制造的水平，它是提高产品质量的重要保证。因此，零件的加工工艺设计和工艺装备的设计又是制造过程的重要组成部分。重点需要解决的问题是进行高水平的工艺设计，设计出定位精度高、加紧可靠而又方便制造的夹具。要求：设计出车床、铣床等至少两种夹具。主要技术参数主要数据为：零件图或工序图上的技术要求；零件的生产纲领中批量生产。进度与完成日期4月1日4月15日 翻译外文资料

2、，搜集相关设计资料。4月16日5月8日 认真分析加工零件的结构特点，分析主要加工表面的表面精度、尺寸精度和其他面的相互位置精度，定出该零件的设计夹具的工序。5月9日5月26日 设计并绘制出机床夹具装配图。5日27日6月02日 设计并绘制夹具零件图。6日03日6月15日 整理设计结果，撰写设计说明书（注：设计说明书的大部分是穿插在上述容中进行的）。系主任签字日期教研室主任签字日期指导教师签字日期指 导 教 师 评 语 指导教师: 年 月 日毕业设计评阅意见表设计题目 机床专用夹具设计评价项目评价标准（A级）满分评 分ABCDE文献资料利用能力能独立地利用多种方式查阅中外文献；能正确翻译外文资料；

3、能正确有效地利用各种规、设计手册等。10109876综合运用能力研究方案设计合理；设计方法科学；技术线路先进可行；理论分析和计算正确；动手能力强；能独立完成设计；能综合运用所学知识发现和解决实际问题；研究结果客观真实。20192017181516131412设计质量设计结构严谨；逻辑性强；语言文字表准确流畅；格式、图、表规；有一定的学术水平或实际价值4037-4032-3628-3125-2724创新能力有较强的创新意识；所做工作有较大突破；设计有独到见解151513-1411-12109工作量工作量饱满；圆满完成了任务书所规定的各项任务。151513-1411-12109总分是否同意将该设计

4、提交答辩：是（ ） 否（ )具体评阅与修改意见： 评阅人： 年 月 日注：1.请按照A级标准，评出设计各项目的具体得分，并填写在相应项目的评分栏中； 2.计算出总分。若总分60分，“设计质量”1009.31N。故本夹具可安全工作。5.3.4 定位误差分析铣削力与夹紧力计算定位孔与定位心轴的配合尺寸取为25f6（在夹具上标出定位心轴配合尺寸25f6）。对于工序尺寸11mm而言，定位基准与工序基准重合，基准不重合误差为=0，基准位移误差为=0.027mm，所以定位误差=+=0.027mm， 而加工尺寸16mm的公差为：=0.12mm，所以，=0.027/3=0.04,因此定位方案合理。5.3.5

5、定向键与对刀装置设计1、定位键：定向键是夹具与机床的联接元件，用来确定夹具与机床工作台之间正确位置。定位键一般使用两个（其距离应尽可能布置得远些），分辨用螺钉紧固在夹具体底面的同一直线位置的键槽中，其下半部分的两侧面与铣床工作台T形槽的配合，使夹具上定位元件的工作表面对于工作台的送进方向具有正确的位置。定向键可承受铣削时产生的扭转力矩，可减轻夹紧夹具的螺栓的负荷，加强夹具在加工中的稳固性。根据参考文献2表6.4-280161999定向键结构如图：图5.3 定向键(80161999)与其与机床连接示意图根据T形槽的宽度a=14mm定向键的结构尺寸如表表5-1 定向键尺寸BLHhD1夹具体槽尺寸h

6、螺钉GB65-2000公称尺寸极限偏差h6极限偏差h8410公称尺寸极限偏差H7140-0.0110-0.0272085.71014+0.013M5*122、对刀装置：对刀装置由对刀块和塞尺组成，其中对刀块用来确定刀具与夹具的相对位置。对刀必须通过塞尺来确定刀具的位置，以免划伤对刀块的工作表面。对刀块为单独的元件，用销钉和螺钉装夹在夹具体便于操作的位置上。常见的标准对刀块有：圆形对刀块，用于加工单一平面时对刀；方型对刀块：用于调整组合铣刀位置时对刀；直角对刀块：用于加工两相互垂直面或铣槽时对刀；侧装对刀块：它安装在夹具体侧面，用于加工两相互垂直面或铣槽时对刀。常用的塞尺有：15mm的平塞尺和工

7、作直径为3mm和5mm的圆柱塞尺两类。其公差均按h8制造。对刀时，铣刀不能与对刀块的工作表面直接接触，以免损坏切削刃或造成对刀块过早磨损，而应通过塞尺来校准它们之间的相对位置，即将塞尺放在刀具与对刀块工作表面之间。采用直角对刀块与平塞尺对刀。确定对刀块的对刀面与定位元件定位表面之间的尺寸，水平方向尺寸为16/2(槽宽一般尺寸)+3（塞尺厚度尺寸）=11mm,其公差取工件相应尺寸公差的1/3。槽宽尺寸为16mm，则水平尺寸公差取（1/3X0.12）mm=0.04mm，对称标注为（110.02）mm，同理确定垂直方向尺寸为8（槽底尺寸）-3（塞尺厚度尺寸）=5mm,槽底长度为自由尺寸，查公差表IT

8、11级公差值为0.09mm，则水平尺寸公差取（1/3X0.09）mm=0.03mm，确定垂直方向尺寸为（50.03）mm。由于本工序是完成此拨叉的槽粗、精铣加工，所以选用直角对刀块。根据/T8044-1999直角对刀块的结构和尺寸如图。塞尺选用平塞尺，其结构如图所示表5-2 塞尺尺寸公称尺寸H允差dC3-0.0060.25夹具上所装的对刀块，可使夹具在一批零件的加工前很好地对刀（与塞尺配合使用）；同时，夹具体底面上的一对定位键可使整个夹具在机床工作台上有一个正确的安装位置，有利于铣削加工。参考文献2选用直角对刀块，其结构尺寸如图所示：图5.4直角对刀块(GB224180 A型)塞尺选用平塞尺，

9、其结构如图所示：图5.5平塞尺(/T8032.1-1999)3、夹具体的设计：由于铣削时的切削力较大，因此，铣床夹具的夹具体不仅要有足够的刚度和强度，其高度和宽度之比也应恰当，一般为H/B11.25以降低夹具的重心，使工件的加工表面尽量靠近工作台面，提高加工时夹具的稳定性。5.3.6 绘制夹具总装图用点化线划出工件的轮廓和主要表面，主要表面是指定位基准面。夹紧表面和被加工表面总装配图上所绘制的工件视为假想的透明体，因此不影响其他元件的绘制。然后按定位元件、对刀引导元件、夹紧机构传动装置为顺序画出各图的具体结构，最后画夹紧件。图5.6 连接螺栓图5.7 定位长圆柱销图5.8 压紧螺母图5.9 连

10、接螺栓图5.10 菱形销螺栓图5.11 菱形销5.12 定位键图5.13 压块机构图5.14 手动螺旋压紧机构、图5.15 夹具体底座图5.16 夹具装配图结 论基于三维的的系列专用夹具毕业设计即将结束。回顾整个过程，经过老师和同学的帮助，还有自己不懈的努力，终于与时定量的完成了这次毕业设计。毕业设计在机械制造与自动化专业中使得理论与实践结合，对理论知识加深了理解，同时也使我们对生产实习的理解和认识得到了强化。本次毕业设计主要是基于三维的专用夹具设计。机械夹具设计的运用了工件定位、夹紧机构等知识。通过此次设计，使我基本掌握了零件的加工过程分析、工艺文件的编制、专用夹具设计的方法和步骤等。学会了

11、查相关手册、选择使用工艺装备等等。本次设计还存在很多不足之处。由于对知识的掌握不够扎实，在设计过程中不能全面地考虑问题。仍需要进一步研究和实践。这次设计，让我对基本理论的综合运用与正确解决实际问题等方面得到了一次较好的训练。提高了思考、解决问题，创新设计的能力。为以后的设计工作打下了较好基础。本设计存在很多不足之处，最后恳请各位老师批评指正！致 通过这一阶段的努力，我的毕业设计说明书理工大学毕业设计终于完成了。在大学阶段，我在学习上和思想上都受益非浅，这除了自身的努力外，与各位老师、同学和朋友的关心、支持和鼓励是分不开的。写作毕业论文是再一次系统学习的过程，毕业论文的完成，同样也意味着新的学习

12、生活的开始。在本论文的写作过程中，AAA老师和BBB老师倾注了大量的心血，我非常感AAA老师和BBB老师在我大学的最后学习阶段毕业设计阶段给予我的指导，从最初的定题，到资料收集，到写作、修改，到论文定稿，他们一遍又一遍地指出设计中的具体问题，严格把关，循循善诱，他们给了我耐心的指导和无私的帮助。为了指导我的毕业论文，他们在百忙的工作中安排时间，他们的这种敬业奉献的精神令人钦佩，在此我向AAA老师和BBB老师表示我诚挚的意。同时，感所有任课老师和所有同学在这四年来给自己的指导和帮助，是他们教会了我专业知识，教会了我如何学习，教会了我如何做人。正是由于他们，我才能在各方面取得显著的进步，在此向他们

13、表示我由衷的意，并祝所有的老师培养出越来越多的优秀人才，桃满天下！参考文献1 朱诗顺,骆素君.机械课程设计简明手册.化学工业出版,20112王先奎,旦主编.机械加工工艺手册.机械工业,20063 王先奎，凤池.机械加工工艺手册第二卷.加工技术卷.机械工业,20064 叶伟昌.机械工程与自动化简明设计手册.机械工业,20015 洪.机械加工工艺手册M .，19966 徐鸿本.机床夹具设计手册M.科学技术，20037 朱冬梅，胥北澜,何建英.画法几何与机械制图-6版，高等教育,20088王光斗，王春福.机床夹具设计手册M.科学技术，20009 黄继昌，徐巧鱼，海贵.实用机构图册.机械工业，2008

14、10 于惠力，新敏.新编实用紧固件手册.机械工业，201111 宏钧.实用金属切削手册M .机械工业，200512市金属切削技术协会.金属切削手册M .科学技术，200213 Machine classification and pose fixture. Prenfice Hall,Inc2002. th 414M.Lv*，X.Yang.Design and manufacture of a shaving cutter with unequal depth gashes.Journal of Materials Processing Technology 129(2002)193-195.

15、附录1 外文资料Machine classification and pose fixture1 fixture in the role of machining Workpiece clamping fixture is a kind of process equipment, it is widely used in mechanical machining of the manufacturing process, heat treatment, assembly, welding and testing processes.In the use of metal-cutting mac

16、hine tools collectively referred to as the jig fixture. N a modern production machine is an indispensable fixture of the process equipment, machining of the workpiece, the processing requirements in order to ensure. First of all to the workpiece and machine tool relative to a correct position, and t

17、his location during processing dose not change the impact of external forces. To this end, during the pre-machining, workpiece clamping must be good .There are two ways to clamp workpiece: one is directly clamping the workpiece in the machine table or on the chuck; the other is the workpiece in the

18、fixture on the fixture. The first method used when the workpiece clamping , the general design requirements have to press lines in the surface to draw the size and location , clamping ,or when the needle is zoned dial indicator to find is after the clamping. This method need special equipment, but l

19、ow efficiency, are generally used for one-piece and small batch production. Large quantities, mostly with the workpiece clamping fixture. With the merits of the workpiece clamping fixtures are as follows. Guarantee the stability of the machining accuracy of workpiece. Workpiece with clamping fixture

20、 ,the workpiece relative to the location of tool and machine tool to ensure the accuracy of the fixture from the technical level of workers , so that a number of workpiece machining accuracy of the line .To improve labor productivity. Workpiece clamping fixture can facilitate the user easily 、rapidl

21、y, and the workpiece dose not need to find is crossed, can significantly reduce the supplementary working hours, to improve labor productivity; workpiece in the fixture after the fixture to improve the rigidity of the workpiece , thus cutting the amount of increase , to improve labor productivity; c

22、an use more pieces of multi-workpiece clamping fixture , and the use of efficient clamping bodies , to further improve labor productivity.To expand the use of machine tools. Machine tools in general use a dedicated machine tool fixture can expand the scope of the process and give full play to the po

23、tential of machine tools to achieve a multi-machine use. For example, the use of a dedicated fixture can be easily Lathe processing small box to the workpiece. .Even in the lathe out of oil, a reduction of expensive dedicated machines, reducing the cost, which is particularly important for small and

24、 medium-sized factories.To improve the operators working conditions. As the pneumatic, hydraulic,electro-magnetic power source, such as the application in the fixture, on the one hand to reduce the labor intensity of workers; the other hand, it guarantees the reliability of the workpiece clamping, a

25、nd to achieve the interlocking machine, to avoid accidents, ensure the operator safety and machine tool equipment.To reduce costs. In mass production after use of fixture, from stem to increase labor productivity, lower level technical workers, as well as lower scrap and other reasons, obviously to

26、reduce the production costs.Fixture manufacturing cost-sharing in a group of workpiece, each workpiece to increase the cost is very minimal, far less than as a result of increased labor productivity and reduce costs. The greater volume of workpiece, fixture made to use has become more significant ec

27、onomic benefits. 2 Fixture Categories2.1 General characteristics of the fixture by Category According to the production in different types in the common characteristics of machine tool fixture. Fixture can be divided into general, special fixture, adjustableclamp, and automatic line of modular fixtu

28、re fixture, such as :( 1) General Fixture. Universal fixture refers to the structure; size has been standardized, and has a certain universal fixture. This type of fixture adaptable can be used to setup the scope of a certain shape and size of various parts. (2) A dedicated fixture. This type of fix

29、ture is designed for a particular part of the processing procedures and the design and manufacture. Relatively stable in the product, the production of large quantities used a variety of special fixture, access to higher productivity and machining accuracy. (3) Adjustable fixture. Adjustable fixture

30、 for general fixture and special fixture and the defects developed a new kind of fixture. Of different types and sizes of the workpiece, simply adjust or replace the fixture at the original location of the individual components and will be used to clamp components. (4) Modular Fixture. Modular fixtu

31、re is a modular fixture. Standard components of the modular with high precision and resistance to abrasion can be assembled into a variety of fixtures. Removable fixture used to clean the assembly after the new fixture left. (5) Automatic line fixture .Automatic line clamp generally divided into two

32、 categories: fixed-type fixture,which is similar to a dedicated fixture; other accompanying a fixture for the use of the workpiece in the fixture, together with the movement, and automatic workpiece along the line from a move to the next position for processing.2.2 Classification by the use of machi

33、ne tools Classification By the use of machine tools can be divided into lathe jig fixtures, milling fixtures, drilling fixtures, hang-bed fixture, jig gear machine, CNC machine tool fixture, automatic machine tool fixtures, accompanied by automatic line, and other fixtures, such as machine tools .Th

34、is is a special fixture design of the classification method used. Dedicated fixture design, the machine group, the type and the main parameters have been determined. Their difference is the cutting forming machine tool movements, so the connection fixture with the machine in different ways. Machinin

35、g accuracy of their different requirements. 2.3 Clamping fixture according to the power source Clamping fixture according to the power source can be divided into manual fixture, pneumatic fixtures, hydraulic fixtures, gas fixtures by force, electromagnetic fixture, vacuumfixtures, fixture, such as c

36、entrifugal force.3 the composition of fixture Although the structure of machine tool fixture range, but their components can be summarized as the following sections.Positioning components. Typically, when the shape of the work piece datum position established, the position will be the basic componen

37、ts of the structure identified.Clamping device. Positioning of the work piece in the fixture, the need to clamp the work piece before processing to ensure that the work piece during processing is not due to external force and undermine its position.The specific folder. Fixture and the skeleton matri

38、x, all the components through the fixture it will constitute a whole.Of the knife or the guide. Tool used to determine position relative to the correct position of components. Of the knife device common in milling fixture. Used to adjust the cutter knife block position before machining.To connectcom

39、ponents. Connected components in the machine tool fixture are to determine the correct position on the component, therefore, can double as a specific folder to connect components. Lathe fixture on the transition plate, the positioning of milling machine fixture on key components is connected.Other d

40、evices or components. According to the processing needs, some degree fixture devices were used by mode device, the whole device, and the balance of the top block and so on. There components or devices specially designed need.Journal of Materials Processing Technology 129(2002)193-195Design and manuf

41、acture of a shaving cutter with unequal depth gashesM.Lv, X.YangCollege of Mechanical Engineering, TaiyuanUniversity of Technology,Taiyuan, Shanxi 030024, PR ChinaAbstract Gear shaving is a gear finishing operation with high efficiency and high precision. When a work gear has been shaved by a shavin

42、g cutter with a true involute profile, the “mid-concave” phenomena inevitably exist around the pitch points of the work gear tooth flanks. Aiming at this problem, a new-style shaving cutter with unequal depth gashes is designed and manufactured. This paper analyses the forming of the gash on the bas

43、is of the slotting principle, and proposes a gash-designing method. Experiment has proven that the shaved gear has a better surface finish that achieves the anticipated effect.Keywords: Gearshaving; Tooth form error, Mid-concave; Unequal depth gashes Introduction Gear shaving is applied widely to ge

44、ar manufacturing in various fields for its high efficiency, high precision and low cost. Nevertheless, there are “mid-concave” phenomena around the pitch points of the work gear it has been shaved using shaving cutter with a trueinvolute profile. This problem seriously affects the tooth surface fini

45、sh and the transmission quality of gear. It is one of the difficulties that many scholars and specialists have been studying and necessitates the improvement of the gear shaving. Thus far various methods have been employed to solve the problem in production that can reduce the mid-concave error to s

46、ome degree but cannot eliminate the error thoroughly. Gear shaving is a complicated process. Under the combined action of many factors, more materials is removed from the gear tooth surface around its pitch points and the “mid-concave” problem is caused consequently 1.If the shaving cutter has no cu

47、tting edges (i.e. no gashes) at its pitch points, the work gear will not be shaved around its pitch points and then the mid-concave error can be greatly reduced. In the light of the analysis, a new concept is proposed, namely, unequal depth gashes (i.e. the depth of the gashes is not the same along

48、the cutter tooth length). In this paper the authors not only state the reason why this shaving cutter can reduce and even eliminate tooth form error, but also analyze the forming of the gash and provide the solution.Principle of slottingThe serrations in the tooth surfaces of a common shaving cutter

49、 are produced on a special slot-generating machine. The principle of slotting is follows (Fig.1). The roll gear (1) and shaving cutter (2) are mounted and fixed on the arbor. Roll gear (1) is located between the upper rack (3) and the lower rack (4) engages with them. The upper rack (3) is fixed in

50、the runner beneath the support and the runner can keep roll gear 910 from axial movement. Lower rack (4) is fixed plate that reciprocates, pushed by the crank-link framework (5). Crank-link framework (5) is driven by electromotor (7) that is shifted by a pulley and then decelerated by reducer (6). S

51、ince the upper rack (3) is fixed, the pitch circle of roll gear (1) moves back and forth with pure rolling action along the pitch line of the upper (or lower) rack. When the diameter of the cutter base circle is equal to that of roll gear pitch circle, the base circle of cutter (2) also makes the sa

52、me movement as the pitch circle of roll gear (1) in roll-generating motion. When the tips of slotting cutter (8) are adjusted to be flush with the pitch line of the upper rack (3), shaving cutter (2) is in mesh with a moving imaginary generating rack that is reproduced in space with the tips. Genera

53、ted involute surface are produced that are identical to the cutter surface, i.e. the slotted gashes are as the cutter tooth surfaces.1. Roller rear2. Shaving cutter3. Upper rack4.lower rack5.crank-link framework6.reducer7.electrotmor8.slotting cutterFig 1 Structure diagram of slotting machineForming

54、 principle of unequal depth gashesDuring the gear shaving process, the meshing of the cutter and the work gear is the meshing of crossed axes helical gears. The shaving cutter is made in the form of a high-precision helical gear that has gashes in the tooth flanks that act as the cutting edges. The

55、cutting edges perform a cutting action depending on the relative velocity over the tooth width between the cutter and the work gear. Traditional shaving methods reduce and eliminate tooth form error by correcting the cutter tooth surfaces. However, a shaving cutter with unequal depth gashes has been

56、 designed by remodeling the gashes on the basis of mechanism of mid-concave error.As far as common shaving cutter is concerned, the profile of its gash bottom is the same as that of the cutter tooth profile, even if gashes differ in shape. As to a shaving cutter tooth with unequal depth gashes, the

57、depth of the gashes varies along the tooth length, which is zero at the pitch point and gradually becomes deeper to its maximum from the pitch point to the top and root of the cutter tooth. Because there are no gashes at the pitch point, there are no cutting edges, that is, no cutting action. Theref

58、ore, the middle part of the shaved tooth profile is not shaved and is only pressed. Thus the gear tooth from error is greatly reduced (Fig.2)Fig2.Gash profile of the shaving cutter with unequal depth gashes.The serrations of the designed shaving cutter are also produced on a special slotting machine

59、. According to the slotting principle, in order to perform gash machining, the cutter gash bottom should have an involute profile. Moreover, the base circle of the cutter involute profile is concentric with that of the gash bottom profile and the diameter of the latter is equal to the diameter of th

60、e roll gear pitch circle. The design method proposed is as follows. The gash bottom is formed by two involutes that intersect at the pitch point of the cutter tooth, and the base circles of the two involutes are concentric with that of tooth involute profile. If two corresponding roll gears are prod