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带自动分度机构的法兰盘加工回转工作台的设计【5张CAD图纸+毕业答辩论文】

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关键词：: 自动分度机构法兰盘加工回转工作台设计

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摘要

本课题是设计一种专门对法兰盘进行加工的带自动分度机构的回转工作台的设计，利用步进电动机进行自动分度的控制，再通过齿轮传动带动心轴和工件转动，配合钻床对法兰盘进行加工，使工件能任意角度的旋转。在单片机的控制下，步进电机每秒钟发出的脉冲数决定了工作台的转位角度。

关键词步进电动机；自动分度；齿轮传动

Abstract

This subject is a special design to the flange with automatic processing of the rotary table, the subject is to use a stepper motor of automatic control, then through the drive spindle and the workpiece rotation, and then processing flange plate of the drilling machine, the work piece can be revolving random angle. Under the control of the microcontroller, the pulse per second from the stepper motor decides the table of the transfer point.

Keywords stepper motor automatic degrees gear

1 绪论1

1.1 回转工作台的简介和应用1

1.1.1 回转工作台的简介1

1.1.2 回转工作台的应用2

2 方案的选择3

2.1 数控回转工作台4

2.2 分度工作台4

2.2.1 开环数控转台4

2.2.2 闭环数控回转工作台5

3工作台的设计7

3.1 加工零件分析7

3.2步进电动机的选择8

3.2.1 步进电动机简介8

3.2.2 步进电动机的选择和参数9

3.2.3单片机控制步进电机原理11

3.2.4 单片机驱动工作台上步进电机设计12

3.3锥齿轮的选择和计算21

3.3.1齿轮设计输入参数21

3.3.2齿轮的材料及热处理21

3.3.3齿轮的基本参数21

3.3.4齿面接触疲劳强度校核23

3.3.5齿根弯曲强度校核24

3.4心轴的设计25

3.4.1轴类零件的技术要求25

3.4.2轴类零件的材料、毛坯及热处理25

3.4.3心轴的较核25

3.5轴承的选择30

3.5.1轴承的分类30

3.5.2 推力球轴承的作用30

3.5.3 轴承的选定31

3.5.4轴承的动载荷和寿命计算31

3.6 夹紧装置的设计32

3.7箱体的设计33

结论33

致谢36

参考文献37

附录38

附录138

附录243

1 绪论

1.1 回转工作台的简介和应用

1.1.1 回转工作台的简介

回转工作台(以下称转台)根据其精度的不同分别是铣床、钻床和坐标镗床、坐标磨床的主要附件，高精度的转台还是计量检验工作中的测量仪器。

（1）国内转台简介

工作台直径是转台主参数，目前我国专业生产厂制造的转台有手动和手动—机动(即通过万向节传动)两种，全是水平式，规格有200, 250, 320, 400和500五种，分度精度按部标为3′。去年获得一机部质量信得过产品奖的武汉机床附件厂生产的400mm转台。

（2）国外转台简介

国外转台品种繁多，按驱动控制方式可分电动、气动、浓压和数控。按分度方式可分机械、光学、数显、端齿盘、钢球、电感和多面体。工业水平发达国家生产的转台品种多、规格全、精度高。没有单一的转台生产厂，如西德霍夫曼公司生产七十多个品种规格的转台，日本津田驹工业株式会社也有四十多种，这两家还生产多种分度头，有的产品既是转台又是分度头，而机床附件又都仅是这两家公司的一个分部。在分度精度上，首推美国莫尔公司的1440齿机械分度转台，其精度高达±0.1″。瑞士的西浦公司生产200-450 mm八种规格的转台，分度精度在4"-18"之间。以前的产品采用蜗轮副分度，近年则多采用光学分度。在锁紧机构上采用钢盘机构，不致使工作台面受力而产生变形。英国OMT光学测量工具公司生产的转台与其座标锉床配套，它采用圆柱销锁紧，.工作台面不受力、结构简单、工艺性也好，但操作不集中，它有12个品种规格，自Φ203一Φ914mm，分度精度在4 "-30″之间，全是光学转台。:日本工业株式会社以生产钢球分度超精密转台而著称，有手动和电气液压驱动两类11个规格，自Φ200-Φ1250mm,分度精度高达±1″。国外转台制造厂，据不完全统计约一百余家，以美、法、英、西德、日本、瑞士最多，下面简略介绍三家典型的公司:

美国莫尔公司(Moors)

1924年创立，五十年代制造转台，生产座标铣床、座标磨床，是美国精密机床厂代表之一，职工380人。莫尔转台，蜗轮副分度，不使用校正装置、操作方便、重复精度好，易于维修，制造难度大。它还可用步进电机调整角度增量，对转台进行程序控制，，实现简单的分度控制。蜗轮副加工是转台的关键，莫尔公司有一整套工艺予以保证，其分度精度为：标准级±12",精密级±6″、超精级±2″。转台直径仅有Φ726mm一种，立卧式，中心高200mm,可当分度头用。莫尔端面齿分度台，1440齿，分度精度高达±0.1″。1440齿分布在8寸的圆周长上即203×Л= 610mm，每齿间距仅为0.432mm，每一齿侧接触仅为百分之几毫米，可见端齿加工的难度。1440齿分度只能细分到十度，加装小角度发生器便可直接读到0.1"。1440齿分度盘是计量莫尔转合的仪器。

西德霍夫曼公司(Hofmann)

霍夫曼是生产分度头和转台颇具盛名的厂家，但这却是该公司一个很小的部分，霍夫曼仅有职工350人，一各类机床附件晶种达几十种，规格200余个，据统计仅转台一项就有30余种126个规格。霍夫曼GR型手动精密机械转台采用180齿的蜗轮，模数1.75，压力角10°。蜗杆升角2°13"，因而分度精度高，且蜗轮副分度误差可由杠杆机构进行补偿，转台结构紧凑、密封性好，转合高度也较低，、分度精度为±5″和±10″两种。日本北川铁工厂生产的R、RI、WR和WRI型转台均自霍夫曼引进，以同型号共商标出厂。

日本津田驹工业株式会社

津田驹主要生产纺织机械，分度头、转台、平口钳等机床附件，约占生产能力10%。现有职工1500人。1937年开始生产转台，是日本最大的机床附件生产厂之一。津田驹生产14种转台、计41个规格， CTK型手动转台，快速进给的CTM型手动转台。

津田驹转台的几种方法简介如下：

1) 手动蜗轮分度：分度精度可达10"-15"，鉴于蜗轮副节距误差和齿面接触精度直接影响分度精度，严格地控制了蜗轮的副加工和装配。

2) 伺服电机分度：利用数控装置发出信号、操纵伺服电机驱动转台。也采用蜗轮副，工作台主轴系用向心止推滚珠轴承，滑动部位用钢球支承，为适用于强力切削选用自动锁紧机构，分度精度为12"-15"。

3) 分度盘分度：为电动转台采用，在电机驱动主轴上装分度盘，分度数为一些固定量，在分度盘侧装有与分度数相等的信号销，电动机根据信号准确停止，一般可分24的约数，分度精度取决于分度盘，当然也受主轴和分度盘不同心度影响。

4) 分度盘：蜗轮并用分度。大型转台多采用并用分度，因为大规格转台定位销相应增大，使电磁吸铁吸力受到限制，大转台受冲击力，惯性力大，为此还采用了减速机构，分度精度可达3"。

5) 端齿盘分度： CTPM-300型转台系超精密自动分度转台，即是此法分度。分度精度可达4"。能承受重切削，自动定心精度高。

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内容简介：: 徐州工程学院毕业设计（论文）任务书徐州工程学院机械设计制造及其自动化专业设计（论文）题目带自动分度机构的法兰盘加工回转工作台设计学生姓名陆爱军班级 04机本2班起止日期 2008.02.25到2008.06.02 指导教师陈跃教研室主任李志发任务书日期 2008 年 2月 25 日1.毕业设计的背景：回转工作台是各种机床上必不可少的配件，目前应用在各种铣床和数控机床上，它配合步进电动机的自动分度加工在机械领域有更大的应用。它能准确的加工所需要的零件，而且加工方便简单。2.毕业设计(论文)的内容和要求：设计内容： 1. 工作台机械机构设计2. 自动分度控制电路设计设计要求：设计一种专门加工法兰盘的钻床工作台，可以针对不同的法兰盘，进行自动分度加工，要求分度方便准确，工作台便于安装。1A0图纸三张，分别为系统装配图和各零件图，电路图；2毕业设计说明书一本（2万字）；3相关外文资料翻译（5000字）。3.主要参考文献：1 实用机械设计手册上册，机械工业出版社，实用机械设计手册编写组编，1992 年9月。2 机械精度设计基础，科学出版社，孙玉芹，孟兆新主编，2004年2月。3 电动机的单片机控制，北京航空航天大学出版社，2002年。4 金属切削原理，上海科学技术文献出版社，上海纺织工业专科学院，刘源灿主编，1984年4月。5 自动控制原理，机械工业出版社，陈玉宏主编，2003年。4.毕业设计(论文)进度计划(以周为单位)：起止日期工作内容备注第1周第2周第3，4周第5，6周第7，8周第9周第10周第11，12周第13，14周第15，16周2008.6.2了解设计的机本要求，查阅相关资料查阅相关资料，写开题报告外文资料翻译设计方案比较选择工作台设计计算分度部分设计计算分度控制电路设计分度程序设计绘制机械和电路图撰写毕业设计说明书答辩准备教研室审查意见：室主任年月日学院审查意见：教学院长年月日附录附录1英文翻译Dimensional ControlIn the early days of engineer, the mating of parts was achieved by machining one part as nearly as possible to the required size, machining the mating part nearly to size, and then completing its machining, continually offering the other part to it, until thedesired relationship was obtained. If it was inconvenient to offer one part to the other part during machining, the final work was done at the bench by a fitter, who scraped the mating parts until the desired fit was obtained, the fitter therefore being a fitter in the literal sense. It is obvious that the two parts would have to be done all over again. In these days, we expect to be able to purchase a replacement for a broken part, and for it to function correctly without the need for scraping and other fitting operations. When one part can be used off the shelf to replace another of the same dimension and material specification, the parts are said to be to be interchangeable. A system of interchangeability usually lowers the production costs, as there is no need for an expensive fiddling operation, and it also benefits the customer in the event of the need to replace worn parts. It also, however, demands that the dimension of mating parts be specified, and that dimensional variations, due to machine and operator shortcomings, be taken into account. Some form of inspection must be introduced to ensure that the manufacture is controlled; this is particularly important, because dimensional errors may not be revealed until some time has elapsed, and often many miles from the place where the machining was done.1. Tolerance and Limits of sizeSince it is accepted that it is virtually impossible to manufacture a part without error, or in the rare event of a part being without error, to be able to proclaim it to be perfect (because the measuring instruments are subject to errors), it is necessary to indicate the maximum errors permitted. The draughtsman must indicate the largest and smallest sizes that the limits of size, and the difference between them is called the tolerance, the actual tolerance must be increased with size. The tolerance should be as large as possible, to keep the cost to a minimum.The method of indicating, on a drawing, the permitted tolerance depends mainly upon the type of operation involved, but local preference must also be taken into account. The following examples will illustrate some of the methods used,(1) Unilateral limits. These are usually used when the distance between two faces, or the diameter of a hole or shaft id specified. For example, when a diameter is being ground, the machinist would prefer to aim at the largest size permitted, so that, in the event of his reaching a diameter that is just a little larger than the maximum size permitted, he can take another cut, knowing that he can use up the whole of the tolerance before the job is rejected. A draughtsman might dimension a nominal 75-0.012 mm diameter shaft as D75. Similarly, a nominal 75mm hole might dimensioned as D75-0.012, the same reasoning applies as for shafts.(2) Bilateral limits. These are usually applied when, for example, the position of a hole is specified. The machine operator may position he hole nearer the datum or further from the datum than intended, he must aim between the limits of position, so that the maximum error can be made without causing the part to be rejected. The center distance between two holes would therefore be specified as, for example, 100+0.02mm.2. Fits are concerned with the relationship between two parts. Consider a shaft and a hole combination: if the shaft is larger than the hole, the condition is said to be of interference; and if smaller than the hole, the condition is said to be of clearance. The interference may be such that the two parts can be assembled only by shrinking, or it may be very slight, so that the parts can be assembled by hand-operated press. Similarly, the clearance can be slight, so that the shaft can rotate easily in the hole, or be large, so that there is ample clearance for bolts to pass through.In order that the precise condition is ensured, the limits of size of both the shaft and the hole must be stipulated.(1) Classes of fit. These are classified as follows.Clearance fit. When the limits of size of both the hole and the shaft are such that the shaft is always smaller than the hole, the fit id said to be a clearance fit.Interference fit. When the limits of size of both the hole and the shaft are such that the shaft is always larger than the hole, the fit id said to be a interference fit.Transition fit. When the limits of size of both the hole and the shaft are such that the condition may be clearance or interference, the fit id said to be a transition fit.(2) Hole-based system and Shaft-based system. In order to obtain a range of degrees of clearance, and degrees of interference, it is necessary to use a wide variation of hole sizes and shaft sizes. For example, a manufacturing company could be making a number of parts, all of a nominal 25-mm diameter, but which are all slightly different in actual limits of size, to suit the actual fit required of each pair of parts. This situation could mean that a large number of drills, reamers, gauges, etc. were required.It is logical that, to reduce this number, a standard hole could be used for each nominal size, and the variation of fit e obtained by making the mating shaft smaller or larger than the hole. This is known as a hole-based system. Alternatively, a standard shaft could be used for each nominal size, and the variation of fit is obtained by making the mating hole larger or smaller, as required. This is known as a shaft-based system. a hole-based system is usually preferred, because it standardizes “fixed size” equipment such as reamer and pluggauges; but a shaft-based system is usually also provided, because sometimes it is more convenient to employ a common shaft to which a number of components is assembled, each with a different fit, and sometimes it is convenient to use bar stock without further machining.3. Systems of limits and fits It is convenient to establish a standardized system of limits and fits, not only to eliminate the need for the draughtsman to determine the limits each time an assembly is detailed, but also to standardize the tools and gauges required. A system of limits and fits should cater for a wide range of nominal sizes. To satisfy the various needs of industry, and should cater for a wide range of quality of work. The system should, if possible, be tabulated, to save the user the trouble of having to calculate the limits of size to suit of the class of fit, the quality of the work, and the size of the part.4. British Standard 4500: 1969, ISO limits and fitsThis standard replace BS 4500 is essentially a revision of BS 1961 to bring the British Standard into line with the latest recommendations of the International Organization for Standardization (ISO). The system refers to holes and shafts, but these terms do not only apply to cylindrical parts but can equally well be applied to the space contained by. Or containing, two parallel faces or tangent planes. The system is tabulated,and covers sizes up to 3150mm.The Numerical Controls developmentThe first electronic computer in the world emerged in 1946, this indicates the mankind has created the tool that can strengthen and replace the mental labour partly . It, and mankind those that create to strengthen tool of manual labor compare among agriculture, industrial society, the qualitative leap has arisen , has established the foundation that the mankind enters the information-intensive society . 6 years later, namely in 1952, the technology of the computer was applied to the lathe , the first numerical control lathe has emerged in U.S.A. From then on, the traditional lathe had produced the change of the quality. In nearly half a century, the numerical control system went through two stages and six generations development The numerical control lathe is regarded as the integrated typical products of electromechanics, play an enormous role among mechanical manufacturing industry , solve structure complicated , accurate , batch little , changeable processing problem of part in the modern machine-building well, and can stabilize the processing quality of the products , improve production efficiency by a large margin . But seen from situation which enterprises face at present, because the numerical control lathe price is relatively expensive, ambassadors enterprises are unable to do what one wants very much to do to relatively make the investment once only. Our country can yet be regarded as a kind of better good plan to the numerical control transformation of the ordinary lathe as the lathe big country . This text proposes to the domestic enterprises current situation at present the economic numerical control of the simple and easy type transforms the thinking and design method for technical staff of numerical controls reference.Numerical control transformation mean to ordinary lathe some position make certain transformation generally, match the numerical control device, thus make the lathe have working ability of numerical control, its purpose is for improving machining accuracy of the old equipment and production efficiency, adapt to many variety and production , short run of part , can make industrial grade can process the high-quality part too than low worker at the same time, reduce investment of technological transformation of the equipment ,etc.Price performance on all these for improving been for lathe than,namely last mechanical performance and the working ability not higher with less money. So transform ordinary lathe as numerical control lathe whether one improve numerical control effective way of rate. Generally speaking, carry on the transformation concrete method of numerical control to the existing ordinary lathe, main transmission make change seldom, is it adopt high-accuracy ball guide screw is it is it give axle already existing ordinary guide screw to enter to replace to enter the transmission of giving. Machinery some transformation after finishing , mix M C S - 51 one-chip computer as numerical control system , with walk into electrical machinery urge the component, first class to moderate gear wheel urge X , sport , Z of axle. In our country in the numerical control lathe is transformed , the microcomputers mostly adopt M C S - type 51 one slice of microcomputers of systematic form, it is a result of very large scale integration development, widely used in the controlled field, develop very fast.According to the function level of the numerical control system , can divide the numerical control system into high , middle and low three to block , the low-grade numerical control system can be regarded as the economy numerical control system. The economy numerical control system is as to standard numerical control system, different periods, the meaning of different countries and regions is different. According to practising the instructions for use of the lathe, rational reduced system, lower costs , can be called economily. Different from the economy numerical control system , call the numerical control system with more complete function numerical control system of the whole function, or is called the standard numerical control system.As regards its function, economy numerical control system general resolution ratio is it give speed to be low moving axle count little , man-machine relatively simple excuse in succession to enter. If position /last control system sharply can last numerical control system not economy. As to its structure, make ring numerical control system general high performance, but of simple structure, the fabrication cost is cheap, can be the most economic numerical control system . So economy numerical control system mainly refer to turning on the numerical control system of the ring at the present stage at home.Have close standard numerical control system of ring, economy numerical control system is it change numerical control system right away there is no ample scope for abilities to turn on. In fact , make ring numerical control system use quite extensive even in our country. The high-performance standard numerical control system costs an arm and a leg, a lot of enterprises are difficult to bear . In addition recommend precise festival produce now, with what whom equipment process with low costs and quality can guarantee, process some equipment, if pursue the high precise equipment blindly, then the production cost increases, this is unnecessary.附录2中文译文尺寸控制在早期的工程（问题）中，配合零件获得的方法是，首先尽可能把一个零件加工到所需的尺寸，再将与它相配合的零件加工到接近所需尺寸，不断将这两个零件试配，再进一步加工直至获得所许的配合关系。如果加工中不便于将两个零件进行试配，则最后的工作是由钳工在钳工台完成，钳工刮削配合零件直至达到所许配合，因此“钳工”在英文中用fitter（适当的，适配的）这一词。显然，两个配合件应该总是在一起（工作）当其中任意一个需要替换时，所有的适配刮削工作又要从头开始。这时，我们期盼能购买到可以替换坏掉零件的替用品，而无须刮削或其它钳工操作就能正常工作。当一个零件一从架子上拿来就可以替换同样尺寸同样材料规格的另一个零件，就说这个零件是可互换的。具有可互换性的系统不必进行高成本的辅助刮削工作，因此降低了产品的成本。在要替换掉磨损的零件时，零件的可互换性对维护而言也是大有好处的。然而，可互换系统要求配合件的尺寸必须规格化，还必须考虑由于加工操作的不足之处引入的尺寸变化。必须采用某种形式的检测方法以确保对加工的控制。这一点非常重要。因为尺寸误差有时可能要过一段时间才会发现，而此时却已远离加工的地方。1 公差与极限尺寸大家知道，事实上零件不可能毫无误差的加工出来，或者说没有误差的零件是不可能的，要说明尺寸的好坏（因为测量仪器必然有误差），就有必要指出最大允许误差。绘图人员必须标明零件正常工作时的最大允许尺寸和最小允许尺寸。这些尺寸的极限值就称作极限尺寸，它们之间的差值称为公差。公差的大小取决于所涉及的加工操作类型、机械工的技能、机床的精确度以及零件的尺寸。对于给定级别的公差，实际公差应随着尺寸的增大而增大。公差应尽可能取大以使加工成本最小。在图上标注公差时，许用公差主要取决于所用操作类型，但也必须考虑本国的优先级。以下用例子说明用到的一些标注方法：（1）单边极限。单边极限通常用于当两个面之间的距离，或孔径、轴径被指定的情况下。例如，当直径要圆整时，机械工更愿意向最大允许尺寸圆整，这样，当他加工到所得直径尺寸略大于最大允许尺寸时，还可以在整个公差范围内再切一次而不产生废品。制图员可能将公称直径是75-0.012mm 的轴标注为D75mm。同样的，公称直径是75mm 的孔也可能标的尺寸是D75-0.012mm，这同样也适用于轴的标注。（2）双边极限。双边极限通常用于：比如当孔的位置已确定的情况下。机床操作人员可能将孔的位置定得较接近或远离所需数据，而且，当孔的加工已经开始，操作人员不可能改变孔的位置，他必须在尺寸位置限度间加工，以便在最大误差时不会使零件变成废品。因此，应将两个孔的中心距规定出来，比如，为100+0.02mm。2. 配合配合是关于两个零件之间的关系。考虑孔和轴的装配；如果轴的尺寸大于孔的尺寸，这种情况称为过盈配合；如果轴的尺寸小于孔的尺寸，这种情况称为间隙配合。过盈配合的两个零件只有通过收缩才能装配，或者过盈量非常小可通过用手压力的操作装配零件。同样，间隙非常小，轴可以很容易的在孔中旋转，或者孔的尺寸大一些，以便于有足够的间隙供螺栓从中穿过。为了确保精确，孔和轴的极限尺寸都必须予以规定。（1）装配分类如下：间隙配合当孔和轴的尺寸界限满足轴总是小于孔，则其配合为间隙配合。过盈配合当孔和轴的尺寸界限满足轴总是大于孔，则其配合为过盈配合。过渡配合当孔和轴的尺寸界限所处的情况可能是间隙也可能是过盈，则称为过渡配合。( 2 ) 基孔制和基轴制。为了得到不同程度的间隙和过盈，有必要使孔和轴的尺寸有变化范围。比如，制造公z_j_(躝_z_司可能生产许多零件，它们的基本直径都是25mm，但它们的实际尺寸都是在允许极限尺寸内稍有不同，以满足每对零件的实际装配要求。这就是说需要大量的钻头、绞刀和量具等。从逻辑上看，要减小钻头、绞刀和量具等的数量，应对每种基本的尺寸用一个标准的孔，通过把与它配合的轴的尺做得稍大或稍小以获得不同的配合关系，这就是基孔制。另一种方法，每种基本尺寸

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