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1 附录 A 四 工位组合机床的设计与研制 摘要 摘要:本文介绍了一种用于加工载重汽车轮毂的单面立式 30 轴钻、扩、铰组合机床,以及机床的设计方法、结构、性能特点和使用操作等。 关键词:组合机床 ;轮毂 ;设计 ;研制 四工位组合机床用于对载重汽车前、中后轮毂 10-27+0.033孔的钻、扩、铰加工。此类机床过去已有的设备相对落后,电气系统、液压系统及机床主要部件相对过时和陈旧。本文介绍的组合机床有较先进的电气控制系统和液压系统,机床的运行采用三菱可编程控制器程序控制,程序可根据加工流程图进行调整,变成方便灵活。它集粗钻、扩加工和精铰加用于一身,自成体系地形成一条圆形加工流水线。该设备占地面积小,加工精度高,性能稳定可靠,是汽车制造工厂加工轮毂不可多得的设备。它是由专用底座,专用主轴箱,专用夹具及钻模板, THL86 立柱, HY80系列滑台及 TD80A动力头, AHY125A回转工作台等组 成。 组合机床的技术发展 1.1 组合机床 组合机床是一种专用高效自动化技术装备,目前,由于它仍是大批量机械产品实现高效、高质量和经济性生产的关键设备,因而被广泛应用于汽车、拖拉机、内燃机和压缩机等许多工业生产领域。所以说组合机床的技术性能和综合自动化水平,在很大程度上决定了这些工业部门产品的生产效率、产品质量和企业生产组织的结构,也很大程度上决定了企业产品的竞争力。 现在组合机床作为机电一体化产品,它是控制、驱动、测量、监控、刀具和机械组建等技术的综合反映。近 年来,这些技术有长足进步,同时作为组合 机床组要用户的汽车和内燃机等行业也有很大的变化,其产品市场寿命不断缩短,品种日益增多且质量不断提高。这些因素有力地推动和激励 2 了组合机床的不断发展。 1.2 组合机床品种的发展 在组合机床这类专用机床中 ,回转式多工位组合机床和自动线占有很重要的地位。因为这两类机床可以把工件的许多加工工序分配到多个加工工位上 ,并同时能从多个方向对工件的几个面进行加工 ,此外 ,还可以通过转位夹具 (在回转工作台机床上 ) 或通过转位、翻转装置 (在自动线上 ) 实现工件的五面加工或全部加工 ,因而具有很高的自动化程度和生产效率 ,被汽车、摩托 车和压缩机等工业部门所采用。 根据有关统计资料 ,德国在 1990 1992 年期间 ,回转式多工位组合机床和自动线的产量约各占组合机床总数的 50 % 左右。应指出 ,回转式多工位组合机床实际上是一种特殊型式的小型自动线 , 适合于加工轮廓尺寸 250mm 的中小件。与自动线相比 , 在加工同一种工件的情况下 ,回转式多工位组合机床所占作业面积要比自动线约小 2/ 3 。 1.3 组合机床柔性化进展迅速 十多年来 ,作为组合机床重要用户的汽车工业 ,为迎合人们个性化需求 ,汽车变型品种日益增多 ,以多品种展开竞争已成为汽车市场竞 争的特点之一 ,这使组合机床制造业面临着变型多品种生产的挑战。为适应多品种生产 ,传统以加工单一品种的刚性组合机床和自动线必须提高其柔性。在 70 年代 ,数控系统的可靠性有了很大的提高 ,故到 70 年代末和 80 年代初 ,像 Alfing 、 Hller2 的运动特性曲线。由于电液比例阀控制系统 Hille 和 Ex2cell2o 等公司相继开发出数控加工模块和柔性自动线 (F TL) ,从此数控组合机床和柔性自动线逐年增多。在 1988 年至 1992 年间 ,日本组合机床和自动线 (包括部分其它形式的专用机床 ) 产量的数控化率已达 32 % 39 % , 产值数控比率达 35 % 51 % ; 德国组合机床和自动线产量的数控化,发动机变型品种日益增多的趋向率为18 % 62 % , 产值数控化率达 45 % 66 % 四工位组合机床的设计 3 .1 工艺方案的确定 组合机床是针对某种零件或某道工工序而设计的,工艺方案又是组合机床设计的关键,它是根据被加工零件的结构特点、加工部位、加工的尺寸精度、粗糙度以及其他技术要求来确定设计的。 被加工件是汽车轮毂零件,在前道立车工序上已加工出 280-0.1的定位圆,要求在 375 的圆周面上加工出 10 个 27+0.033的孔,其位置公差为 0 0.12,粗糙度为 3.2。根据以上要求,工艺方案应确定粗精加工分开进行,即先钻 25的孔,然后扩孔到 26.6,再精饺孔到 27,考虑到零件的加工精度和工序集中原则,粗精加工合并成一道工序在一台机床上进行。由此确定机床的钻、扩、铰三个工位,加之装卸工件工位,故命名为四工位组合机床。 .2 配置型式及其结构方案 机床的配置型式主要取决于被加工零件的加工精度和工艺方案,既要考虑能实现工艺方案以保证零件的加工精度、技术要求和生产效率;又要考虑操作方便,易于维 修,冷却和排屑情况良好。该机床的配置型式属于大型组合机床,总重量约为 21t,总功率 17.5kW四套专用夹具安装在直径 1250m 的回转工作台上,形成四个工位,与之对应的立柱上安装 HY80标准滑台,滑台上安装标准动力头和专用主轴箱,主轴箱的加工中心与回转工作台的回转中心对中,成垂直立式布局。装卸工件和加工工件可同时进行,互不干扰,既机床的切削时间和辅助时间重合,从而提高机床的工作效率。 组合机床的主要组成部分 .1 床身 床身部件必须有足够的承载能力和足够的刚度动态性能及过载储备稀疏,以保证各部件之间能长 期保持其正确的相对位置。组合机床的刚度和部件之间的精度保持性要由床身部件来保证。本机床的床身不见主要由回转工作台底座、立座底座、立柱和立柱垫等构成。它们起着组合机床的基础骨架作用。床身部件包括配重在内的重量达组合机床总重量的 70%以上,因而具有良好 4 的刚性和抗振性能,为保证机床的加工精度奠定了良好的基础。 .2 滑台 滑台之用来实现进给运动的动力部件,它主要由滑台,滑台座和液压油缸三部分组成。滑台座固定在立柱上,液压油缸体固定在滑座上,活塞杆与滑台相互连接,工作时,液压油缸固定,活塞杆带着滑台在滑座的导轨上作往返运动。本机床液压滑台属于大型滑台,有足够的能量储备。滑台的工作有快进、共进和快退三种状态。其动作是由电气系统和液压系统共同控制的。在滑台上安装有动力头和主轴箱,滑台顶部装有钢丝绳滑轮组,另一端在立柱中装有配重块,目的是使滑台在滑座上移动轻便,并可防止滑台端过重而下滑。 .3 动力头及主轴箱 动力头是主轴运动的驱 动装置,它带动主轴箱的各个输出主轴使刀具作主体运动。本机床钻、扩、饺孔刀具直径分别为 25mm、 26.6mm和 27mm,被加工零件材料为 35CrMoV,硬度 HRC28 32, 考虑到扭矩储备系数,机床采用标准 TD80A 型动力头,主电机为 15KW。转速为 970r/min,输出轴转速为 475r/min。主轴箱是组合机床重要部件之一,其作用是根据被加工件的加工要求,安排各主轴的位置,并将电机的动力按不同的转速比输出分配给各工作主轴,使主轴得到要求的转速和转向,以满足对零件的加工。主轴箱主轴的排列根据被加工零件的工艺要 求进行设计,并与回转工作台上的夹具工位向对应,主轴箱的传动齿轮及传动轴可选标准件。 .4 主轴及钻模板 主轴的结构取决于零件的加工工艺以及主轴的受力情况。对于钻削加工的主轴,受轴向切削力较大,应采用推力球轴承或滚锥轴承定位。主轴与刀具的连接方式采用莫氏 3#导向套接杆,刀具的长短比例可视加工情况调整接杆。用于钻、扩孔加工的主轴转速为 175r/min。切削速度 V=13.7m/min,进刀量 S=0.17mm/r.铰孔加工的主轴转速为 50r/min,切削速度 V=4.24m/min,进 5 刀量 S=0.6mm/r,进刀速 度 Sv=30mm/min。 钻模板主要起对刀具的辅助定位作用,防止刀具在加工时摆动,从而提高被加工件的精度。 .5 回转工作台 回转工作台是多工位组合机床的输送部件。本机床的回转工作台分四个工位, 1 工位用于装、卸工件, 2.3.4 分别是钻、扩、铰工位。回转工作台作单方向的回转运动,相当于一条圆形自动生产线,其结构紧凑,生产效率高,可以方便的实现电气自动控制。该机床是齿盘定位回转工作台,其主要组成有:花盘、工作台体、多齿定位盘、集屑槽、呼吸器、卡紧油缸、活塞、转位齿轮、转位离合器、液压阀、转位齿条等。回转工作台 的齿盘是圆周分布的一对相互啮合的端面齿轮,靠圆周多齿啮合定位,具有定位精度高和刚性好的特点,所以在转台上无论径向力、轴向力或切向力,都可以起到自动定心的作用。 .6 夹具 夹具使用来防止并固定被加工零件的。正确选择加工用定位基准是确保加工精度的重要条件。夹具的尺寸精度和安装精度的高低直接影响到零件的加工精度,本机床共有四套尺寸相同的夹具,均布在回转工作台上并与回转台中心形成同心圆流水线。夹具主要有四个夹具体、定位圈、夹紧油缸等组成。每套夹具有四个夹紧油缸,等分固定在夹具体的四个方向上,夹紧工件时受力均衡, 防止零件变形。定位圈时夹具的关键部件,必须使四套夹具的定位圈尺寸公差相一致,而且四套夹具的回转中心与回转工作台的回转中心也应绝对重合,才能保证零件的加工精度。 .7 液压系统 机床的液压系统相当于人体的血液喜欢系统,被加工零件的夹紧、放松,工作台的抬起、旋转和落下,动力头滑台的快进、共进和快退等都是靠液压系统来实现。液压系统主要由液压站集中控制,液压电机为 22KW,液压泵为变量叶片泵,滑台的动作是由一个三位五通电磁阀和调速阀来控制。回转工 6 作台的抬起、落下、回转和复位,以及工件的夹紧和放松,主要由三个两位四 通电磁阀来控制。另外专设一路由程序控制的对液压滑台自动定时润滑。 .8 电气系统 本机床采用 F1-60MR 三菱可编程控制器作为中央控制枢纽。它是由中、大规模集成电路组成,具有强大的逻辑控制功能和逻辑存储功能,响应速度快,功耗小,体积小,受命小,可靠性高,通用性强,可不受条件限制地对程序进行在线编程、调试和修改。它可以实现对程序的自我诊断和故障检测,可进行逻辑运算和编程的控制,定时和计数的控制,可以容易地实现机、电、液一体化。电气系统的交流在、输出控制主要有主轴电机,液压电机,冷却电机。直流输出主要控制液压站的十路电磁阀。 电气系统的硬件主要有可编程控制器、变压器、接触器、操纵按钮和保险器、整流二极管和续流二极管 、以及行程开关等组成;软件主要包括主程序,同时有为程序服务的各个期间的输入输出地址标和程序梯形图等。 机床的操作分调整和自动两种方式,调整方式为手动控制机床的单步操作;自动方式由程序控制按加工流程图实现自动循环。 .9 冷却系统 机床外部设有专用的带脚轮的冷却箱,便于维修和清理,冷却泵电机为0.12KW。容量为 50L/min,冷却水到达钻模板后分成三路,每一路有 10个导向水嘴,对应于 10 把刀具,俄有效地实现刀具的冷却。冷却泵在滑台工进时由程序控制自动启动,实施对被加工工件的冷却,工进到终点时自动关闭。 4 组合机床的安装调试及精度检验 在组装过程中始终贯穿着对系统部件的不断调试,以及对影响加工尺寸的主要部件的自身精度和结合精度进行调整。 系统的调试是根据各个系统的要求和机床工作循环图的要求来对电气系统、液压系统、冷却系统、主机系统自身和相互之间进行有关调整。 对主要部件自身精度和结合精度进行调整是指以下几个方面: 7 ( 1)机床侧底座、立柱底座的安装水平。 ( 2)机床侧底座、立柱底座、机床导轨的扭曲。 ( 3)主轴孔轴线的径向跳动。 ( 4)主轴孔轴线对机床导轨的平行度。 ( 5)夹具衬套孔轴线或样件孔轴线对导轨的平 行度。 ( 6)主轴和夹具衬套孔或样件孔对导轨的等距度。 ( 7)回转工作台的回转中心与主轴箱的加工中心的同轴度。 5 试车 当工件状态旋钮开关置于“调整”位置时,操作各按钮如夹紧、放松、前进、后退等,可进行机床的单步动作,此功能主要用于机床试运行或刀具的调整等。当开关置于“自动”状态时,机床的动作完全由程序自动进行控制,每次装卸完工件后,只需按“夹紧”、“抬起”按钮,机床就会自动循环、周而复始的工作下去,直到按“停止”按钮为止,此功能主要用于对零件的自动加工。 经试车运转一切正常,并对零件进行了加工试切验证, 经过机械工业部第十七计测试中心检测,尺寸公差及精度符合零件图纸的技术要求。 6 本组合机床特点 (1)机床上的通用部件和标准零件约占机床零部件总量的 以上,因此设计和制造的周期短,经济效益好。 (2)机床采用专用的夹具、刀具及钻模板,一次性调整后,其加工质量全靠工艺装备来保证,对操作人员的技术水平要求不高,且劳动强度低。 (3)该设备占地面积小,加工精度高,性能稳定可靠,是汽车制造厂加工轮毂的专 用设备。 (4)机床有钻、扩、铰及装卸四个工位,装卸及加工同步进行,因此机床的生产效率高,每小时可加工零件 件以上,加工质量稳定。 8 (5)机床采用可编程控制程序控制,因而自动化程度高,且机床的动作在不改变电气线路的情况下可在线编制程序,随机调整。 附录 B Design and reseach of four engineering location association lathes17 ABSTRACT Abstract:This text introduce one is it process form , truck of hub vertical 30 axle get into , expand , cut with scissors and make the lathe up to use for, And lathe design method , structure , performance characteristic and uses and operates etc.ing. Keywords: Combination machine; Hub Design; Reseach Preface Four worker location association lathe use for10-27+0.033 to drill , hub of hole under truck , expand , cutting with scissors processing. This kind of existing equipment in the past of lathe lagged behind relatively, electric system , hydraulic pressure system and main part of lathe were relatively out of date and outmoded. Association lathe that this text introduce have more advanced electric control system and hydraulic pressure system, the operation of the lathe adopts Mitsubishis programmable controller procedure to control, the procedure can adjust according to processing the flow chart , become convenient and flexible. It is thick to bore , is it process and not precise to is it is it is it all over , afford to establish ones own system to used in to add to cut with scissors to expand for it 9 to collect. This equipment is small in floor space, the machining accuracy is high, it is reliable that performance is steady, it is the manufacturing plant of the automobile that processes the equipment with rare hub. It is by the special-purpose base , special-purpose main shaft case, special-purpose jig and boring the template , THL86 post, HY80 serial slippery platform and TD80A power head, AHY125A turn round workingbench ,etc. make up. 1. Make the technical development of the lathe up 1.1 Association lathe It is the automatic technical equipment of a kind of special-purpose university to make the lathe up, At present. Because it is still the key equipment that the engineering goods in enormous quantities were realized high-efficiently , the high quality and economy produced, Widely used in such a lot of industry production fields as the automobile , tractor , internal-combustion engine and compressor ,etc. So say that makes the technical feature of the lathe and comprehensive automation level up , determine these industrial department production efficiency , product quality and enterprise of product produce the structure organized to a great extent, have determined the competitiveness of the enterprise products to a great extent too. Make the lathe up as the integrated products of electromechanics now, It controls, urges, measures, control, the comprehensive reflection of technology that the cutter and machinery are set up ,etc. The past 20 years, Technology the make considerable progress, at the same time as make up lathe group want automobile and internal-combustion engine of user trade change a great deal too, Its life-span of product market is shortening constantly, the variety increases day by day and quality is being improved constantly. These factors have promoted and encouraged making the constant development of the lathe up effectively. Make the development of the variety of lathe up 10 In making the lathe up this kind of special-purpose lathe , Turning round type many workers location association lathes and transfer machine occupy very important status. Because two lathe these can is it get a lot of location , Engineer of processing , have to assign a lot of processing process of work piece, and can process several of the work piece from a lot of directions at the same time , In addition, Can also through transfer to location jig (turn workingbench round at the lathe ) or through transfer to location , upset device (at transfer machine ) realize 5 processing or processing of work piece, Therefore have very high automatic degree and production efficiency , is adopted by such industrial departments as the automobile , motorcycle and compressor ,etc. According to relevant statistical data, Germany is here 1990-1992 During annual ,Person who turn round many worker location association lathe and output of transfer machine is it is it make about 50 , lathe of total amount up to take each to invite. Should point out , Turning round type many workers location association lathes are a small-scale transfer machine of a kind of special pattern in fact, Suited to processing medium and small one of the size 250mm of outline. Compared with transfer machine, In case of processing the same kind of work pieces, person who turn round many worker location association lathe account for homework area invite than transfer machine 2/ 3little. Make the flexibility progress of the lathe up rapidly During the last ten years, Regarded as the auto industry which makes important users of the lathe up , In order to cater to individualized demands of people, Automobile person who become variety increases day by day, Is it become characteristic , automobile of market competition one of already to compete with many variety, This is it make up lathe manufacturing industry face many variety challenge of production of becoming etc. to make. In order to adapt to many variety production, With process single rigidity of variety make up the lathe and 11 transfer machine must raise his flexibility tradition. In the 1970s, the dependability of the numerical control system was improved a lot, So with the beginning of the eighties by the end of the seventies, like Alfing , H Movement characteristic curve of ller2. Because electric liquid proportion valve control system Hille and Ex2cell2o ,etc. company develop numerical control process module and flexible transfer machine in succession (F TL), Numerical control made the lathe and flexible transfer machine up and increased year by year from then on. Between 1988 and 1992, Japan made the lathe and transfer machine (the special-purpose lathe including some other forms ) up the numerical control rate of the output has already reached 32- 39, The numerical control rate of output value reaches 35- 51; Germany make lathe and numerical control , transfer machine of output up, engine for 18 - 62 trend rate that variety increase day by day of becoming etc., the numerical control rate of output value is up to 45 %-66 % 2 The designs of four engineering location association lathes 2.1 Sureness of a craft scheme Make up lathe to a certain part or some Engineer process and design, The craft scheme is the key to making the lathe up to design, It according to process into structure characteristic of part , process position , size precision , roughness and other specification requirement that process is it is it design to confirm to come. It is an automobile hub to process one .In before whether dish set up car the processes last 280-0.1localization round already, Require that processes the hole of 10 times 27+0.033 on circumference one of 375, The persons on a public errand of its position are 0-0. 12, The roughness is 3. 2. Craft scheme should confirm crude finish machining goes on separately , Namely get into 25 hole first, then reaming reach 26. 6, precise dumpling hole reach 27, Consider the machining accuracy and process of the part concentrate the principle , thick finish machining 12 is amalgamated a process is carried on on a lathe. Therefore confirm drill of lathe , expand , cut with scissors three worker person, in addition worker of loading and unloading work piece location, so named four engineering location association lathes . 2.2 Dispose the pattern and structure scheme The disposition pattern of the lathe depends on the machining accuracy of the part and craft scheme processed mainly, Should consider that can realize the craft scheme soes as to ensure the machining accuracy , specification requirement and production efficiency of the part ; And also it is easy to operate to consider, easy to maintain, cool and arrange the bits in sound conditionly . The disposition pattern of this lathe belongs to and makes the lathe up large-scaly, Total weight is about 21t, total power 17. 5kW Four sets of special-purpose jigs are installed on the gyration workingbench of diameter 1250m, Form four pieces of engineering location , Install HY80 standard slippery platform with its corresponding post, Install the standard power head and special-purpose main shaft case on the slippery platform, Gyration centre on and cant turn machining center , main shaft of case round workingbench of to in, become the vertical vertical overall arrangement. Loading and unload the work piece and processing the work piece can go on at the same time , does not interfere each other, Already cutting time and auxiliary time of the lathe has been coincident, thus improve the working efficiency of the lathe . 3.Make the main component of the lathe up 3.1 Lathe bed The lathe bed part must be enough bearing capacity and enough dynamic performance of rigidity and overload and store sparsly, so as to ensure that can keep its correct relative position for a long time between every part. Make up rigidity and precision keeping of part of lathe guarantee by the lathe bed part 13 Lathe this lathe bed is it turn workingbench base round , set up of base , post and post cushion ,etc. form mainly to disappear. They play a making the basic skeleton of the lathe up role. Lathe bed part including counterweight weight is it make lathe total more than 70% of weight up to reach, therefore have good rigidity and antivibration performance , settle good foundation for guaranteeing the machining accuracy of the lathe . 3.2 Slippery platform To is it is it enter give power part of sport to realize to used for slippery platform, It mainly by slippery platform, slippery pedestal and hydraulic pressure cylinder 3 part make up. The slippery pedestal is fixed on post, the cylinder block of hydraulic oil is fixed on slide , cylinder rod and slippery platform join each other, When working, hydraulic pressure cylinder regular, cylinder rod bring slippery platform make round sport at guide of slide. This slippery platform of hydraulic pressure of lathe belongs to the large-scale slippery platform, enough energy stores . Slippery work of platform is it enter , stock and soon retreat 3 kinds of states altogether soon to have. Its movement was controlled together by the electric system and hydraulic pressure system. Install power heads and main shaft case on the slippery platform , is equipped with the pulley block of steel wire rope on the slippery tops , another end contains the counterweight one in the post, the purpose is to make the slippery platform move lightly on the slide , and can prevent the slippery ends from being overweight and glide . 3.3 Power head and main shaft case The power head is the drives of sports of the main shaft , It drive each , main shaft of case output main shaft make cutter decide body sport. This lathe is got into, expanded , the diameter of hole cutter of dumpling is 25mm , 26 respectively. 6mm and 27mm, It is 35CrMoV to process the part material, hardness HRC28-32, Consider the torsion stores coefficient , the lathe adopts the power very beginning 14 of standard Model TD80A , the main electrical machinery is 15KW. The rotational speed is 970r/min, the rotational speed of the output shaft is 475r/min. The main shaft case makes one of the important parts of the lathe up , Function its according to process processing of piece require , arrange every position of main shaft, is it distribute every work main shaft to output power of electrical machinery according to different rotating ratio, make the main shaft get the rotational speed required and change direction, Israel satisfies the processing of the part. 3.4 Main shaft and boring the template The structure of the main shaft depends on receiving the strength situation of the processing technology of the part and main shaft . For get into main shaft processed to sharpen , cut strength to be relatively heavy axial , should adopt thrust ball bearing or get away the bearing of the awl orientate. Main shaft and connection way of cutter adopt 3 lead set connect pole , size proportion of cutter can is it process situation change and answer the pole to depend on. The rotational speed of main shaft that used for boring , reaming is processed is 175r/min. Cut speed V =13. 7m/min, feed amount S =0. 17mm/r. The rotational speed of main shaft of reaming and proce

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