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生产车桥后桥减速器壳体组合车床中镗孔的精镗机床设计,生产,后桥,减速器,壳体,组合,车床,镗孔,机床,设计

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车桥后桥减速器壳体设计摘 要本设计的内容可分为机械加工工艺规程设计和机床专用夹具设计两大部分。首先，通过分析车桥后桥减速器壳体。运用机械制造技术及相关课程的一些知识，解决减速器壳体在加工中的定位、加紧以及工艺路线的安排等方面的相关问题，确定相关的工艺尺寸及选择合适的机床和刀具，保证零件的加工质量。其次，依据推动架毛坯件和生产纲领的要求及各加工方案的比较，制定出切实可行的推动架加工工艺规程路线。最后，根据被加工零件的加工要求，参考机床夹具设计手册及相关方面的书籍，运用夹具设计的基本原理和方法，拟定夹具设计的方案，设计出高效、省力、经济合理并且能保证加工质量的夹具。关键词 机械加工、工艺规程、专用夹具、减速器壳体、后桥减速器ABSTRACTThe design of the content can be divided into a point of order processing machinery and machine tools designed for the two most fixture design. First of all, through the promotion ofplaner, that promote the planer-processing role. Use of machinery manufacturing technology and related programmes of knowledge, promoting the solution-processing in the position to step up and the line of the arrangement, and so on related issues, establishing the process and choose a suitable size and machine tools, spare parts processing quality assurance . Secondly, the basis for promoting the rough-pieces and production and processing requirements of the Programme of the programme, to promote the development of a practical point of order-processing line. Finally, in accordance with the requirements of the processing parts processing, machine tool fixture design reference manual and related aspects of the books, use of fixture design of the basic principles and methods, the programme drawn up fixture design, design efficient, effort, economic and reasonable to ensure the quality of processing Fixture.Key words: Machining process planning special fixture Reducer housing rear axle reducer主要符号表符 号 单 位 意 义 M 牛.米 弯矩F 牛 力 n 转每分 转速 Z 齿数 m 模数 d 毫米 直径 v 米每秒 速度 S 转每毫米 进给量 L 毫米 长度 P 千瓦 功率 T 牛.米 扭矩 q 升每分 流量 p 帕 压力 t 秒 时间第1章 绪 言1.1 组合机床的发展现状组合机床是以通用部件为基础，配以按工件特定形状和加工工艺设计的专用部件和夹具，组成的半自动或自动专用机床。组合机床是由大量通用部件和少量专用部件组成的工序集中的高效率专用机床。组合机床一般采用多轴、多刀、多序、多面或多工位同时加工的方式，生产效率比通用机床高几倍至几十倍。由于通用部件已经标准化和系列化，可根据需要灵活配置，能缩短设计和制造周期。因此，组合机床兼有低成本和高效率的优点，在大批、大量生产中得到广泛应用，并可用以组成自动生产线。组合机床有大型组合机床和小型组合机床两大类，他们不仅在体积和功率上有大小之别，而且在结构和配置型式等方面也有很大的差异。大型组合机床按配置型式可分为：具有固定式夹具的单工位组合机床、具有移动式夹具的（多工位）组合机床、转塔车桥后桥减速器壳体式组合机床。 目前，为了使组合机床能在中小批量生产中得到应用，往往需要应用成组技术，把结构和工艺相似的零件集中在一台组合机床上加工，以提高机床的利用率。这类机床常见的有两种，可换车桥后桥减速器壳体式组合机床和转塔式组合机床。组合机床未来的发展将更多的采用调速电动机和滚珠丝杠等传动，以简化结构、缩短生产节拍；采用数字控制系统和车桥后桥减速器壳体、夹具自动更换系统，以提高工艺可调性；以及纳入柔性制造系统等。车桥后桥减速器壳体是组合机床的主要部件之一，按专门要求进行设计，由通用零件组成。其主要作用是，根据被加工零件的加工要求，安排各主轴位置，并将动力和运动由电机或动力部件传给各工作主轴，使之得到要求的转速和转向。车桥后桥减速器壳体按其结构大小，可分为大型车桥后桥减速器壳体和小型车桥后桥减速器壳体两大类。大型又可分为通用车桥后桥减速器壳体和专用车桥后桥减速器壳体两种。专用车桥后桥减速器壳体根据加工零件特点，及其加工工艺要求进行设计，由大量的专用零件组成，采用刚性主轴来保证加工孔的精度。通用多轴箱按专用要求设计，由通用零件及少量专用零件组成，采用非刚性主轴，加工时，需由导向装置引导刀具来保证被加工孔的位置精度。1.2 设计目的及要求1.2.1 目的 机械制造技术基础是以机械制造工艺技术设备为主要内容的技术科学，是机械类专业的一门主要课程，具有很强的实践性。因此在完成了理论教学和实践教学后，还需要对学生进行机械零件加工工艺设计的实际训练，使学生通过工艺设计获得综合运用所学过的全部相关课程（如机械制造技术基础，互换性及技术测量，金属学与热处理学）进行零件工艺及结构设计的基本能力，能根据被加工零件的技术要求，运用夹具设计的基本原理和方法，学会拟订夹具设计方案，完成夹具结构设计，初步具备设计出高效、省力、经济合理并能保证加工质量的专用夹具的能力，培养学生熟悉并运用有关手册、标准、图表等技术资料的能力，进一步培养学生识图、制图、运算和编写技术文件等基本技能。1.2.2 要求 掌握编制机械加工工艺规程的方法，能正确解决中等复杂程度零件在加工中的工艺问题。 根据已学的知识，提高结构设计的能力，通过设计夹具的训练，根据被加工零件要求，设计出能保证加工技术要求，经济、高效的工艺装备。 认真复习设计有关的知识，并查阅有关的资料，手册让学生会使用与机械加工工艺和工装设计有关的手册及图纸资料。1.3 机械加工工艺设计的现状 机械制造业是国民经济的支柱产业，现代制造业正在改变着人们的生产方式、生活方式、经营管理模式乃至社会的组织结构和文化。生产的发展和产品更新换代速度的加快，对生产效率和制造质量提出了越来越高的要求，也就对机械加工工艺等提出了要求。 在实际生产中，由于零件的生产类型、形状、尺寸和技术要求等条件不同，针对某一零件，往往不是单独在一种机床上用某一种加工方法就能完成的，而是需要经过一定的工艺过程。因此，我们不仅要根据零件具体要求，选择合适的加工方法，还要合理地安排加工顺序，一步一步地把零件加工出来。1.3.1 机械加工工艺规程制订生产过程是指将原材料转变为成品的全过程。它包括原材料的运输、保管于准备，产品的技术、生产准备、毛坯的制造、零件的机械加工及热处理，部件及产品的装配、检验调试、油漆包装、以及产品的销售和售后服务等。机械工工艺过程是指用机械加工方法改变毛坯的形状、尺寸、相对位置和性质使其成为零件的全过程。机械加工工艺过程的基本单元是工序。工序又由安装、工位、工步及走刀组成。规定产品或零件制造过程和操作方法等工艺文件，称为工艺规程。机械加工工艺规程的主要作用如下：1.机械加工工艺规程是生产准备工作的主要依据。根据它来组织原料和毛坯的供应，进行机床调整、专用工艺装备的设计与制造，编制生产作业计划，调配劳动力，以及进行生产成本核算等。2.机械加工工艺规程也是组织生产、进行计划调度的依据。有了它就可以制定进度计划，实现优质高产和低消耗。3.机械加工工艺规程是新建工厂的基本技术文件。根据它和生产纲领，才能确定所须机床的种类和数量，工厂的面积，机床的平面布置，各部门的安排。1.3.2机械加工工艺规程的种类机械加工工艺过程卡片和机械加工工序卡片，是两个主要的工艺文件。对于检验工序还有检验工序卡片；自动、半自动机床完成的工序，还有机床调整卡片。机械加工工艺过程卡片是说明零件加工工艺过程的工艺文件。机械加工工序卡片是每个工序详细制订时，用于直接指导生产，用于大批量生产的零件和成批生产中的重要零件。1.3.3 制订机械加工工艺规程的原始资料制订机械加工工艺规程时，必须具备下列原始资料：1.产品的全套技术文件，包括产品的全套图纸、产品的验收质量标准以及产品的生产纲领。2.毛坯图及毛坯制造方法。工艺人员应研究毛坯图，了解毛坯余量，结构工艺性，以及铸件分型面，浇口、冒口的位置，以及正确的确定零件的加工装夹部位及方法。3.车间的生产条件。即了解工厂的设备、刀具、夹具、量具的性能、规格及精度状况；生产面积；工人的技术水平；专用设备；工艺装备的制造性能等。4.各种技术资料。包括有关的手册、标准、以及国内外先进的工艺技术等。第2章 加工零件的工艺设计2.1 计算生产纲领，确定生产类型 如零件图所示为车桥后桥减速器壳体零件，该产品年产量为2000台，设其备品率为15%，机械加工废品率为2%，现制定该零件的机械加工规程。 技术要求：1、 未注明的铸造圆角半径为23。2、 退火处理。N=Qn(1+a%+b%) =20001(1+15%+2%)件/年 =2340 件/年 车桥后桥减速器壳体零件的年产量为2340年/件，现已知该产品属于轻型机械，查阅教材生产类型与生产纲领的关系，确定其生产类型为中批生产。2.2 零件的分析 车桥后桥减速器壳体零件的图样的视图正确、完整，尺寸、公差及技术要求齐全。由零件图可知其材料为ZG45。该材料具有较高的强度、耐磨性、良好的切削性能，适用于承受较大的应力，要求耐磨的零件。总之而言，该零件外型轮廓不大，各表面精度、尺寸精度都不高。 2.3 确定毛坯根据车桥后桥减速器壳体零件材料ZG45确定毛坯为铸件，又已知零件生产纲领为2340件/年，该零件轻型机械，可知，其生产类型为中批量生产，毛坯的铸造方法选用砂型机器造型。为清除残余应力，铸造完成后应安排人工时效。2.3.1 铸件尺寸公差 铸件尺寸公差分为16级，由于是中批生产，毛坯制造方法采用砂型机器造型，由工艺手册查得，铸件尺寸公差等级为CT10级，选取铸件错箱值为1.0mm。2.3.2 铸件机械加工余量 对中批量生产的铸件加工余量由工艺手册查得，选取MA为G级，查得铰孔单边加工余量为0.1mm，扩孔单边加工余量为0.9mm，端面粗铣余量为3.5mm，所以各表面的总余量见表1.1。由工艺手册可得铸件主要尺寸公差见表1.2。表2.1 各加工表面总余量/mm 加工表面基本尺寸加工余量等级加工余量数值说明E面16G3.5单面加工余量E面16H3.5单面加工余量D面16G3.5单面加工余量C面16H3.5单面加工余量F面8H3.5单面加工余量孔9H99H1扩孔和铰孔的单边总加工余量孔26H96H0.1铰孔单边的加工余量表2.2 主要毛坯尺寸及公差/mm零件尺寸加工余量毛坯尺寸公差CT163.5及3.52311163.5及3.5231183.511.5101601611120121012012102.3.3 零件毛坯综合图零件毛坯综合图一般包括以下内容：铸造毛坯形状、尺寸及公差、加工余量与工艺余量、铸造斜度及圆角、分型面、浇冒口残根位置、工艺基准及其他有关技术要求等。零件毛坯综合图上技术条件一般包括下列内容。（1）合金牌号。（2）铸造方法。（3）铸造的精度等级。（4）未注明的铸造斜度及圆角半径。（5）铸件的检验等级。（6）铸件综合技术条件。（7）铸件交货状态。如允许浇冒口残根大小等。（8）铸件是否进行气压或液压试验。（9）热处理硬度。零件毛坯综合图如下图2.1所示。图2.12.4工艺规程设计2.4.1 定位基准的选择 本零件是一个带角度的铸造车桥后桥减速器壳体，总的各种精度要求不高。为了避免不必要的基准误差，各端面加工采用了互为基准原则，加工两个6H9孔时采用了9H9孔及端面定位，这就使加工遵循了“基准重合”的原则，即设计基准与工序基准重合。2.4.2 选择加工设备及工艺装备由于生产类型为中批量生产，且零件的加工精度要求也不是很高，故加工设备宜以通用机床为主，辅以少量专用机床。其生产方式为以通用机床加专用夹具为主，辅以少量专用机床的流水生产线。工件在各机床上的装卸及各机床间的传送均由人工完成。确定工序尺寸一般的方法是由加工表面的最后工序往前推算，最后工序的工序尺寸按零件图样的要求标注。当无基准转换时，同一表面多次加工的工序尺寸只与工序（或工步）的加工余量有关。有基准转换时，工序尺寸应用工艺尺寸链解算。第3章 组合机床设计3.1 制定工艺方案零件加工工艺方案将决定组合机床的加工质量、生产效率、总体布局和夹具结构等。通过对被加工零件为车桥后桥减速器壳体分析，其材料为HT20-40，硬度为HB175-255。 因此选用粗镗、半精镗、精镗的工艺方法。由于所加工零件是孔径较大的多层壁孔，所以主轴选用非刚性主轴。3.2确定切削用量及选择刀具确定工序间余量： 为使加工过程顺利进行并稳定保证加工精度，必须合理地确定工序余量。根据组合机床设计1P52生产中出常用的组合机床对孔加工的工序间余量，见表3-1表3-1孔加工常用工序余量加工工序加工孔径（mm）直径上工序间余量(mm)粗镗4067半精镗20800.71.2801501.01.51501.31.6精镗300.200.25301300.250.401300.350.50根据生产经验，在组合机床上进行孔加工的切削用量，推荐按表3-2选取。表3-2镗孔的切削用量工序刀具材料（米/分）f（毫米/转）粗镗硬质合金钢20250.250.80半精镗硬质合金钢30500.401.50精镗硬质合金钢70900.120.15（H7）3.3确定切削力、切削扭矩、切削功率及刀具耐用度根据选定的切削用量（主要指切削速度及进给量f），确定切削力，作为选择动力部件及夹具设计的依据；确定切削扭矩，用以确定主轴及其他传动件（齿轮、传动轴等）的尺寸；确定切削功率，用以选择主传动电机（一般指动力箱电机）功率；确定刀具耐用度，用以验证所选刀具是否合理。根据生产实践及试验研究成果，已经整理出来的硬质合金镗刀在灰铸铁材料上镗孔的切削力P、切削扭矩M、切削功率N、刀具耐用度T的计算公式由组合机床设计参考图册2P10可知如下：刀具耐用度： KT2KT3KT4KT5KT6KT7 （1） 轴向力：Px=0.051t1.2f0.65HB1.1Kpx2 （2）周向力：Pz=5.14tf0.75HB0.55Kpz2K pz3 （3） 切削功率： （4）运用以上公式借助Excel软件计算出加工各孔的刀具耐用度如表3-3所示，加工各孔受的轴向力、径向力、切削功率如表3-4所示。表3-3 刀具耐用度孔直径 tsHBkt2kt3kt4kt5kt6kt7耐用度T粗镗15053.52.20.22200.7710.7710.591258.4110382.420.42200.7710.5910.591289.1110302.550.42200.7710.5910.591289.112039.872.50.2672200.7710.5910.591256.980312.60.2672200.8610.3310.591258.89037.72.70.22200.8610.3310.591258.810031.52.20.22200.8610.3310.591256.9半精镗150451.50.42200.7710.77111.5380.6110451.20.42200.7710.59111.5291.7110451.10.42200.7710.59111.5291.7120451.10.42200.7710.59111.5291.780451.10.42200.8610.33111.5326.3904510.42200.8610.33111.5292.11004510.42200.8610.33111.5326.3精镗150600.40.122200.7710.77111.61313.9110600.380.122200.7710.59111.61312.3110600.350.122200.7710.59111.61312.3120600.350.122200.7710.59111.61312.380600.30.122200.8610.33111.61267.290600.30.122200.8610.33111.61267.2100600.30.122200.8610.33111.61267.2表3-4 加工各孔受的轴向力、径向力、切削功率孔直径tfHBKpx2Kpz2Kpz3轴向力Px圆周力Pz切削功率N粗镗1504.90.52201.140.96194.13279.251.831104.50.42201.140.96173.51216.931.421104.50.42201.140.96173.51216.931.421204.50.452201.140.96179.36236.971.55804.50.42201.140.96173.51216.931.42904.50.42201.140.96173.51216.931.421004.50.452201.140.96179.36236.971.55半精镗1501.20.42201.140.96115.0557.850.381101.20.42201.140.96115.0557.850.381101.20.42201.140.96115.0557.850.381201.20.42201.140.96115.0557.850.38801.20.22201.140.9619.5934.400.22901.20.22201.140.9619.5934.400.221001.20.22201.140.9619.5934.400.22精镗1500.40.142201.140.9612.048.770.061100.30.132201.140.9611.376.230.041100.30.132201.140.9611.376.230.041200.30.132201.140.9611.376.230.04800.30.122201.140.9611.305.860.04900.30.122201.140.9611.305.860.041000.30.122201.140.9611.305.860.043.4 被加工零件图图3-1 被加工零件图3.5、组合机床“三图一卡”3.5.1 内容加工示意图是在工艺方案和机床总体方案初步确定的基础上绘制的。是表达工艺方案具体内容的机床工艺方案图。它是设计刀具、辅具、夹具、多轴箱和液压、电气系统以及选择动力部件、绘制机床总联系尺寸图的主要依据；是机床总体布局和性能的原始要求；也是调整机床和刀具所必需的重要文件。3.5.2 注意事项加工示意图应绘制成展开图。按比例用细实线画出工件外形。加工部位、加工表面用粗实线。必须使工件和加工方位与机床布局相吻合。为了简化设计，同一多轴箱上尺寸完全相同的主轴（即指加工表面，所用刀具及导向，主轴及接杆等规格尺寸、精度完全相同时）只画一根，但必须在主轴上标记与工件孔号相对应的轴号。一般主轴的分布不受真实距离的限制。当主轴彼此间很近或需设置结构尺寸较大的导向装置时，必须以实际中心距严格按比例画，以便检查相邻主轴、刀具、辅具、导向等是否干涉。主轴应从多轴箱端面画起；刀具画加工终了位置。采用标准通用结构只画外轮廓，但必须加注规格代号；对一些专用的结构，如专用的刀具、导向、刀杆托架专用接杆或浮动卡头等，需用剖视图表示其结构，并标注尺寸、配合及精度。3.5.3 选择刀具选择刀具应考虑工件材质、加工精度、表面粗糙度,排屑及生产率等要求。只要条件允许，应尽量选用标准刀具。刀具锥柄插入接杆孔内长度，在绘制加工示意图时应注意从刀具总长处减去。由于以上条件的限制，本次设计选用的刀具为硬质合金=30的精镗刀，（GB143978）如左图所示。3.5.4 主轴类型、尺寸和外伸长度的确定主轴类型主要依据工艺方法和刀杆与主轴的连接结构进行确定。主轴轴颈及轴端尺寸主要取决于进给抗力和主轴刀具系统结构。如与刀杆有浮动连接或刚性连接，主轴则有短悬伸镗孔主轴和长悬伸钻孔主轴。综合考虑加工精度和具体工作条件，按表15选定主轴的外伸长度L、外径D和内径.对于精镗类主轴，因其切削转矩较小，如按其来确定主轴直径，则刚性不足。实际生产中，应取较大值，来保证轴的刚度满足要求。表3-5 各轴基本参数轴号加工直径（mm）主轴直径d(mm)主轴外伸尺寸L(mm)n(r/min)f(mm/r)f(mm/min)110、80 501151010.440110、90501151010.440120、10060 115930.454015050115850.5 403.5.5 计算主轴直径(1)各轴转距转矩=圆周向力加工孔半径 T=PZR （5）由表(1-5)可知各主轴所受的转矩和功率如下表 表1-6主轴转速、功率轴孔数圆周力F/N转矩T/(N mm)功率P/KW2433.8620608.352.842433.86216932.842473.94 26066.73.101279.2520943.751.83（2）强度校核 选择45刚做为主轴的材料，根据机械制造装备设计3P136公式（4-7）提供的在强度条件下计算主轴直径的方法校核。 d （6）d1.826=50.06d/d=50.06/50=1.01.05 误差在5%内，故可以选50的主轴 d1.826=50.9mm d/d =50.9/50=1.021.05 d/d =60/54.14=1.111.05 为了安全起见，轴径应大于50，故选择60的主轴； d1.826=50.33mm d/d =50.33/50=1.011.05 误差在5%内，故可以选择50的主轴。根据机械制造装备设计P136公式（4-8）提供的在强度条件下计算主轴直径的方法校核。 d （7）式中：d-轴的直径 T-轴所承受的转距（N.mm） 许用剪切应力（MPa）;45钢=31MPa； B-系数，当材料的剪切弹性模量G=8.1104MPa，非刚性主轴=0.50/m,B=1.948;传动轴=10/m,B=1.638。d1.948=23.72mm d/d=50.06/50=1.01.05 误差在5%内，故可以选50的主轴d1.948=23.64mm d/d =50.9/50=1.021.05 d/d =60/54.14=1.111.05 为了安全起见，轴径应大于50，故选择60的主轴；d1.948=23.43mmd/d =50.33/50=1.01 Z2 =58由 Z / Z= Z/ Z得: Z =693)确定驱动轴0的坐标位置如图2-1，首先量出半径R3，根据R2配0轴与1轴联的 Z/Z 的齿轮。R2=182.66mm 取m=4由公式可知 由于距离较远,而电机齿轮最大齿数为25,故预取电机齿轮齿数为25。由公式可得与此啮合的传动轴齿数为66。4)验证各主轴转速n=100=99转/分 n=100=100转/分n=100=94转/分转速相对损失在5%以内，符合设计要求。5）用中间传动轴2兼作调整手柄轴，其转速如下：n2=100=117转/分轴2的转速相对较高，操作时省力，位置适当，可满足要求。6）采用R12-2型叶片泵，直接由驱动轴0经一对齿轮=直接传动。n泵 =100=114转/分由机床设计手册5第三卷n泵在100-1000转/分之内，满足要求。图3-6 主轴坐标图表3-7主轴坐标值1轴2轴轴X0Y0X1Y1XY20627411618612862轴轴轴XYXYXY2161463302601043403.10 齿轮尺寸设计 主动齿轮：根据机械原理第六版，齿轮机构机器设计部分提供的计算方法来计算齿形带的外形和传动设计。孔的加工主轴和传动轴1的中心距a为125.75mm,模数为2，参照GB/T1356-88，可以得到，。则齿轮各参数的计算公式如下：中心距： 总齿数：=126拟用传动比：=63分度圆直径：d=zm （13）d=d=632=126mm齿顶高：ha=ha*m （14）ha=ha=12=2mm齿根高：hf=(hz*+c*)m （15）hf=hf=(1+0.25) 2=2.5mm齿全高：h=(2ha*+c*)m （16）h=h=(2+0.25) 2=4.5mm齿顶圆直径：da1=(z+2ha*)m （17）da1=da=(63+2) 2=130mm齿根圆直径：df=(z-2ha*-c*) （18）df1=(63-2-0.25) 2=121.5mm基圆直径：db=d1cos （19）db1=126cos200=118.40齿距：p= m （20）p=3.142=6.28mm基圆齿距：pb=pcos （21）pb=6.28cos200=5.97mm 齿厚： s= m/2=3.142/2=3.14 mm （22） 齿槽高： e=m/2=3.14 mm （23） 顶隙： c=c*m=0.252=0.5 mm （24）轴上齿轮的各参数如下：Z=61分度圆直径：d=zmd=d=612=122mm齿顶高：ha=ha*mha=ha=12=2mm齿根高：hf=(hz*+c*)mhf=hf=(1+0.25) 2=2.5mm齿全高：h=(2ha*+c*)mh=h=(2+0.25) 2=4.5mm齿顶圆直径：da1=(z+2ha*)mda1=da=(61+2) 2=126mm齿根圆直径：df=(z-2ha*-c*)df1=(61-2-0.25) 2=117.5mm基圆直径：db=d1cosdb1=122cos200=114.6齿距：p= mp=3.142=6.28mm基圆齿距：pb=pcospb=6.28cos200=5.97mm 齿厚： s= m/2=3.142/2=3.14 mm 齿槽高： e=m/2=3.14 mm 顶隙： c=c*m=0.252=0.5 mm轴上齿轮各参数如下：Z=58分度圆直径：d=zmd=d=582=116mm齿顶高：ha=ha*mha=ha=12=2mm齿根高：hf=(hz*+c*)mhf=hf=(1+0.25) 2=2.5mm齿全高：h=(2ha*+c*)mh=h=(2+0.25) 2=4.5mm齿顶圆直径：da1=(z+2ha*)mda1=da=(58+2) 2=120mm齿根圆直径：df=(z-2ha*-c*)df1=(58-2-0.25) 2=111.5mm基圆直径：db=d1cosdb1=116cos20=109齿距：p= mp=3.142=6.28mm基圆齿距：pb=pcospb=6.28cos200=5.97mm 齿厚： s= m/2=3.142/2=3.14 mm 齿槽高： e=m/2=3.14 mm 顶隙： c=c*m=0.252=0.5 mm 轴上齿轮各参数如下：总齿数： Z=69分度圆直径：d=zmd=d=692=138mm齿顶高：ha=ha*mha=ha=12=2mm齿根高：hf=(hz*+c*)mhf=hf=(1+0.25) 2=2.5mm齿全高：h=(2ha*+c*)mh=h=(2+0.25) 2=4.5mm齿顶圆直径：da1=(z+2ha*)mda1=da=(69+2) 2=142mm齿根圆直径：df=(z-2ha*-c*)df1=(69-2-0.25) 2=133.5mm基圆直径：db=d1cosdb1=138cos20=129.68齿距：p= mp=3.142=6.28mm基圆齿距：pb=pcospb=6.28cos200=5.97mm 齿厚： s= m/2=3.142/2=3.14 mm 齿槽高： e=m/2=3.14 mm 顶隙： c=c*m=0.252=0.5 mm油泵轴的齿轮：根据机械原理10第六版，齿轮机构机器设计部分提供的计算方法来计算齿形带的外形和传动设计。参照GB/T1356-88，可以得到，取m=4,又已知Z0=25，Z3=22。 根据机械原理10第六版P327表 （104）齿轮各参数的计算公式如下：中心距：a=m(Z1+Z)/2=4（2522）/2=94mm总齿数：Z0+Z3=47节圆直径：d=zmd3=224=88mm齿顶高：ha=ha*mha3=14=4mm齿根高：hf=(hz*+c*)mhf3=(1+0.25) 4=5mm齿全高：h=(2ha*+c*)mh3 (2+0.25) 4=9mm齿顶圆直径：da=(z+2ha*)mda3 (22+2) 4=96mm齿根圆直径：df=d-2hfdf388-25=78mm3.11 校核对各个齿轮进行分析，知主动齿轮比起过桥齿轮和驱动齿轮更容易失效，据机械设计17（高等教育出版社，濮良贵主编）P202 提供的计算方法校核。接触疲劳校核1.接触疲劳许用应力： （25）查得接触疲劳寿命KHN1=0.96按齿面硬度查得齿轮的接触强度疲劳极限2.接触疲劳计算应力： （26）式中：弹性影响系数，单位为；齿轮强度用的载荷系数；齿轮水平方向受力，单位为N.m；齿轮分度圆直径，单位为mm；b齿轮宽度，单位为mm;齿数比。计算载荷系数： （27）查得使用系数=1.00查得动载系数=1.0 齿间载荷分配系数 = 1.1齿向载荷分布系数所以： 对=20的直齿齿轮，=2.5，查得=189.816.84MPa576 MPa因此 ，合适弯曲疲劳校核1.弯曲疲劳许用应力： （28）查得弯曲疲劳寿命KFN1=0.85按齿面硬度查得齿轮的弯曲强度疲劳极限Flim=750MPa2.弯曲疲劳计算应力： （29）式中：齿轮强度用的载荷系数；齿形系数；应力校正系数；b-齿轮传动的齿宽系数;m齿轮模数。计算载荷系数K取法如接触疲劳校核，取K=1.27查得齿形系数为2.80，应力校正系数为1.55 =因此 ，合适。结 论本次毕业设计主要为了检验过去所学的知识的专业综合应用。通过本次毕业设计，使我对过去所学知识进行了较为系统的回顾，不仅对车桥后桥减速器壳体的作用及工作的效率有了一定的了解，而且初步具备了设计组合机床的能力，组合机床是以大量通用部件为基础，配以少量的专用部件所组成的一种高效专用机床，它因为生产效率高，加工精度稳定，设计研制周期较短，自动化程度高所以特别适用大批量生产。这次的设计感到颇为有收获，使我在过程中无形的总结了不少的宝贵经验，一笔不小的财富，在我的整个设计过程中，由于老师的悉心指导，加上同学的耐心帮助，使我在大学里最后一个设计中受益匪浅，也是在综合性最强的一次设计中得到了实践性的锻炼最多的一次，为我以后步入工作岗位打下了坚实的基础。对此，学生对您们表示衷心的感谢和深深的敬意。致 谢本设计在选题、设计研究及设计说明书的完成整个过程中始终得到指导老师的悉心指导。加上同学的共同努力，历经三个月的毕业设计终于按时完成了。本次生产车桥后桥减速器壳体，组合车床中镗孔的精镗机床设计原理基本正确、结构紧凑、工艺性良好、结构基本合理、加工质量稳定，基本上满足了任务书的要求。当然这次设计对我们这些理论知识不扎实，实际设计水平有限，幸亏有老师的悉心教导和同学的帮助才使我能按时完成设计任务。但是，由于自己缺少对事物理性认识的深刻性，设计中难免存在很多较大的失误和错误，请指导老师给予批正。在整个设计过程中，老师给予提供图纸和一些参考材料，使我得以顺利完成设计，在此深表感谢！老师对我严格的要求和教诲将在我以后的人生道路上竖起风标指我前航，为以后步入工作岗位打下了坚实的基础。对此，学生对您们表示衷心的感谢和深深的敬意。同时在设计过程中，同学也给予了很的帮助和支持。我们共同研究，互相探讨，使我们之间营造了一个良好的团体协作精神，这也是我们的设计得以顺利完成的另一主要因素。 最后学生向在百忙之中评阅本论文的各位老师表示衷心的感谢!参考文献1沈阳工业大学，大连铁道学院，吉林工学院.组合机床设计M.上海：科学技术出版社，19872大连组合机床研究所.组合机床设计参考图册M. 北京：机械工业出版社，19753李庆余，张佳主编.机械制造装备设计M.北京：机械工业出版社，20034谢家瀛.组合机床简明设计手册M. 北京：机械工业出版社，19925机床设计手册编写组.机床设计手册M.第三卷：部件、机构及总体设计.北京：机械工业出版社，19866第一汽车制造厂工艺装备设计室.齿轮传动多轴头设计M. 北京：机械工业出版社，19777赵长发主编.机械制造工艺学M. 哈尔滨：哈尔滨工程大学出版社，20038曾志新，吕明.机械制造技术基础M.武汉：武汉理工大学出版社，20019 顾维邦.金属切削机床M.北京：机械工业出版社，199510 孙桓 陈作模主编.机械原理M.第六版.北京：高等教育出版社，200111 彭文生，李志明，黄华梁.机械设计M. 北京： 高等教育出版社，200212吴宗泽，罗圣国.机械设计课程设计M.北京：高等教育出版，199813杨黎明，黄凯，李恩至，陈仕贤.机械零件设计手册M.北京：国防工业出版，199014 杨培源，朱福元.液压系统设计简明手册M.北京：机械工业出版，199515 刘华明.金属切削刀具设计简明手册M.北京：机械工业出版社，197816 廖念钊，莫雨松，李硕根，杨兴骏.互换性与技术测量M.第四版.北京：中国计量出版.198117 濮良贵，纪名刚主编.机械设计M.第七版. 北京： 高等教育出版社，2001附件1：毕业设计(论文)指导教师评语学生: 学号: 专业: 年级: 指导教师评语: 指导教师签名: 20 年 月 日附件2：毕业设计(论文)评阅人评语学生: 学号: 专业: 年级: 题目: 生产车桥后桥减速器壳体，组合车床中镗孔的精镗机床设计 评阅人评语: 评阅人签名: 日期:20 年 月 日附件3：毕业设计(论文)答辩小组评语学生: 学号: 专业: 年级: 题目: 生产车桥后桥减速器壳体，组合车床中镗孔的精镗机床设计 答辩小组评语: 答辩成绩: 组长签名: 附件4： Numerical control technology development Numerical control system develop biref history and trend the first electronic computer in the world borned 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, numerical control system go through two stage and six development of generation. The stage of numerical control (NC ) (1952-1970 years) The operation of the early computer is low in speed, influence not also big scientific caculation and data processing at that time, but cant meet the needs of real-time control of the lathe . People have to adopt the digital logical circuit to put up and become the special-purpose computer of a lathe as the numerical control system, known as the hardware and connect numerical control (HARD-WIRED NC ) , abbreviate as the numerical control (NC ). With the development of components and parts, does this stage go through y? of the sixth of the twelve Earthly Branches? First generation in 952 -Electron tube ; Second generation in 1959 -Transistor; The third generation in 1965 -Small-scale integrated circuit. The stage of numerical control of the computer (CNC ) (1970 - now) By 1970, the small-scale computer industry in common use has already appeared and produced by batch. Then transplant it over as the key part of system of numerical control, enter computer numerical control stage from now on (whether due in common use two words omit computer). By 1971, in the world for the first time two central part most of computer Company , INTEL of U.S.A. , -arithmetic unit and controller , adopt the technology intergration of the large scale integrated circuit on a chip, call it microprocessor (MICROPROCESSOR ) , can call central authorities punish Entrance (abbreviate as CPU). The microprocessor is applied the numerical control system by 1974. This because being function too strong, minicom control one lathe ability have rich (use for controlling many lathes at that time, call it team control ), have more rational economy than the adoption microprocessor. And the minicomputer dependability at that time was unsatisfactory. Early microprocessor speed and function although enough high, can solve through many processor structure. Because the microprocessor is a key part of the all-purpose computer , so still called the numerical control of the computer. By 1990, the performance of the PC (personal computer , is used to calling the computer at home ) has already developed into very high stage, can meet the demand which is regarded as the key part of the numerical control system . The numerical control system entered the stage based on PC from then on. In a word, the computer went through three generations too at numerical control stage. Namely the fourth generation in 1970 -Minicom ; The fifth generation in 1974 -The microprocessor and the sixth generation of 1990 -Because of PC (call PC-BASED abroad). The ones that were also wanted and is pointed out are, though has already renamed as the numerical control of the computer (namely CNC ) abroad, and our country is still used to being called the numerical control (NC ). So our daily numerical control that speak, has already referred to the numerical control of the computer in fact. Future development trend of numerical control 1. 3. 1 continue to open , based on PC six generation cubic meter to develop Characteristic of enriching on the basis of opening , low cost , high dependability , software and hardware resource that PC has etc., more systematic manufacturers of numerical control will go on this road . Adopt PC as front machine of it , is it deal with man-machine interface , programming , network communication ,etc. problem to come at least, undertaken the task of numerical control by the already existing system. The friendly man-machine interface that the PC has, will run through all numerical control systems. Telecommunication , will diagnose long-rangly and maintain more general. Develop to high speed and high accuracy This is meeting the need that the lathe is developed in the high-speed and high-accuracy direction. Develop toward intellectuality With the constant infiltration and development in the field of computer of artificial intelligence, the intelligent degree of the numerical control system will be improved constantly. 1)Use the adaptive control technology Numerical control system can of the detection procedure some important information, and adjust the relevant parameters of the system automatically, achieve the goal of improving systematic operation state. 2)Introduced to the expert system and guided and processedExperienced operator and experience of expert, universal law and special law of processing deposit system, regard parameter database of the craft as support, set up the expert system with artificial intelligence. 3)Introduce the trouble and diagnose the expert system (4)Intelligent digital servo drive Can through discern load automatically , adjust parameter automatically, is it urge system win the best operation to make. Second, necessity 2 of lathe numerical control transformation. 1, Watch the necessity transformed a little Looking from microcosmic, the numerical control lathe has the following and outstanding superiority more than the traditional lathe , and superiority the come from numerical control might of computer system include. 2. 1. 1 can process such complicated parts as the curve coming out in traditional machine tooling , curved surface ,etc. Because computer have superb operation ability, can instantaneous to calculate out each coordinate axis instantaneous amount of exercise that should move accurate, so can compound into the complicated curve or curved surface . 2. 1. 2 can realize automation that process, and flexible automation, thus efficiency raise than the traditional lathe by 3-7 times. Because the computer has memory and stores ability, can remember and store the procedure input , then carry out automatically according to the order that the procedure stipulates , thus realize automation. So long as numerical control lathe changes a procedure , can realize the automation that another work piece is processed , thus make single piece and produce automation of must using in small batches, so known as realizing flexible automation . 2. 1. 3 The precision of 3 processing parts is high, the size is dispersed degree small, it is easy to enable assembling, no longer need to repair the damaged parts of a machine and supply replacements . 2. 1. 4 concentration that can realize many processes , reduce the frequently carrying among the lathes of part. 2. 1. 5 has such many kinds of self-containment functions as autoalarm , controlling , automatic compensation automatically ,etc., therefore can realize nobody guards and processes for a long time 2. 1. 6 is by the above five spin-off advantages. For instance: Have reduce workers labour intensity, has saved the workforce (a person can guard many lathes ), reduce frocks, shorten trial production of new products cycle and production cycle , can make fast reaction ,etc. to market demand . The above superiority could not be imagined by forefathers , was an extremely great break-through. In addition, the numerical control of the lathe pursues FMC Foundation in such enterprises information-based transformations as (flexible manufacturing unit ) , FMS (flexible manufacturing system ) and CIMS (CIMS ) ,etc. Numerical control technology has already become key technology of automation of manufacturing industry and basic technology. 2. 2, See the necessity transformed in macroscopic Look from macroscopic, the army of the industrially developed country, the peoples mechanical industry, by the end of the 70 s, already begin to use the numerical control lathe on a large scale at the beginning of the eighties. Its essence is, adopt the information technology to carry on technological transformation to the traditional industry (including the army , the peoples mechanical industry ). Except that adopt the numerical control lathe in the course of making, FMC, outside the FMS , pursue CAD , CAE , CAM , fictitious to make and pursue MIS (the management information system ) , CIMS ,etc. in production management in product development also. And increase the information technology , including the content in artificial intelligence ,etc. in the products that its produce. Adopt information technology carry on the deep transformation to foreign countries army , the people mechanical industry (call it the informationization), make products of them competitiveness strengthen very at international military products and market of civilian goods finally. And we are 20 years for about backwardness than developed country in traditional industry of technological transformation of information. In the owning amount of lathe of our country, there is only 1 by 1995 in the proportion (numerical control rate ) of the numerical control lathe . 9%, and Japan had already been up to 20 in 1994. 8%, so a large number of electronic products are imported every year. This states the necessity of numerical control transformation of the lathe from macroscopic too. Third, the markets of the lathe and production line numerical control transformation 3. 1, Market of numerical control transformation of the lathe The total amount of the lathe at present of our country is more than 3,800,000, and the total amount of numerical control lathes is 11 among them. 340,000, namely the numerical control rate of lathe of our country is less than 3%. In the past 10 years, the annual production of numerical control lathe of our country is about 0. 6-0. 80,000, annual output is about 1,800 million yuan. The annual production numerical control of the lathe turns rate into 6%. To account for more than 60% of our country more than 10 years such as enlistment age such as lathe; In the lathe under 10 years, automatic / semi-automatic lathe is less than 20%, there are very fewer such automatic production lines as FMC/FMS ,etc. (the automatic and semi-automatic lathe of U.S.A. and Japan accounts for more than 60%). It is obvious most manufacturing and production of enterprise of us , is it equip hopeless great number traditional lathe to process, and more than half is the old lathe in above 10 years of enlistment age. Have quality to be poor with the equipment products come out to process variety little of low grade with high costs, thus uncompetitive on world, domestic market, influence products , market , benefit of an enterprise directly, influence the existence and development of enterprises. So must improve the numerical control rate of the lathe in a more cost-effective manner . 3. 2, The numerical control of import equipment and production line transforms the market Our country has introduced the technology , equipment and production line to carry on technological transformation from foreign countries in a lot of enterprises since reform and opening-up. According to incomplete statistics, from 10 year past 1979-1988, the whole country introduce technological transformation project have 18446 items, about 165. 800 million dollars. In these projects, most projects have played a due role for the economic construction of our country. But some introduce projects for various reasons, equipment or the production line cant run well , even paralysed, make the benefits of enterprises influenced , the serious one makes enterprises get into a difficult position . After some equipment , production line introduce from foreign countries, it is kind for some to digest and assimilate, the spare part is not complete, it is improper to safeguard, the result operates badly ; Some only pay attention to introducing the equipment , instrument , production line while introducing , ignoring software , craft , management ,etc., causing the project to be incomplete, the potentiality of the equipment cant be given play to; Some cant even start and run , have not given play to the role of should have ing ; Some products of production line sell quickly, but because equipment fault can is it produce up to standard to reach; Some cause loss because energy consumption is high , the product percent of pass is low; Some have already introduced longer time, have needed to carry on technology innovation. All sorts of reasons make some equipment not create the wealth , is consuming the wealth instead Equipment , production line that cant use these pieces of burden, one heavy stock assets very too, it is the wealth to repair. So long as find out main technological difficult point, solve key technology problem, can minimum investment vitalize the heaviest stock assets, strive for to the greatest economic benefits and social benefit. This is a great transforming the market too. Content and excellent and scarce of fourth , numerical control transformation 4. 1, Rise of the transforming industry abroad In such developed countries as U.S.A. , Japan and Germany ,etc., their lathe transformation is regarded as the new economic growth trade, full of life, the straight place is at gold age. Because the constant progress of the lathe and technology, the transformation of the lathe is an eternal subject . The industry that transforms lathe of our country, enter into the new trade relying mainly on numerical control technology from old trade too. In U.S.A. , Japan , Germany , transform with numerical control technology the lathe and production line have wide markets, have already formed the new trade transformed in the lathe and production line numerical control. In U.S.A., lathe transformation industry call lathe regeneration family property. The famous company which is engaged in the recycled family property is as follows, Bertsche project. U.S.A. get treasure Company already open and run the company in China. In Japan, lathe transformation industry call lathe refit (Retrofitting ) the family property. The famous company of the repacking industry is as follows, that engaged in Big Wei project group , hillock three mechanical company , a thousand generation Tian worker machine Company , wild rugged engineering company , Hamada engineering company , mountain this engineering company ,etc. 4. 2, Content of the numerical control transformation There are the following several points in the numerical control of the lathe and production line main content of transformation: First resume the original function , diagnose and resume to the trouble part existing in the lathe , production line ; Second NC, addend show the device at ordinary lathe, or add the numerical control system, transform into NC lathe , CNC lathe Third renovate , in order to improve the precision , efficiency and automatic degree , renovate to machinery , electric part, reassemble and process the mechanical part, resume original precision; Go on newer to his CNC system which is unsatisfied with the production demand with the newest CNC; Fourth technology innovation or technological innovation, in order to improve performance or grade, or in order to use the new craft , new technology, carry on more extensive technology innovation or technological innovation on the original foundation, the ones that improved the standard with grade were renovated by a relatively large margin. , Numerical control transformation excellent and scarce. The capital cost , delivery date are short that 1 reduces Compared with the situation that purchase the new lathe , can generally save 60%-80% of the expenses , it is low to transform the expenses. Especially the large-scale , special lathe is especially obvious. General large-scale lathe transformation, spend new lathe 1/3 to purchase expenses only, delivery date is short. But there are special circumstances, if the making and installation of high-speed main shaft , automatic switch of tray overly takes a lot of work , costly, transform cost raise 2-3 , compared with the situation that purchase the new lathe , can only save 50% investment to be about often. It is reliable that 2 mechanical performance is steady, the structure is limited Such basic parts as the lathe bed , post utilized ,etc. are all heavy and firm casting components, but not the welding component, transform lathe after performance high of high quality, can continue to use for many years as the new equipment . But receive mechanical restriction of structure originally, unsuitable to make the breakthrough transformation familiarizes with the equipment, benefits and operates maintaining While buying the new equipment , do not understand whether new equipment can meet its processing demand . It is quite different to transform , can calculate out the working ability of the lathe accurately ; In addition, has used because for many years, the operator has already understood about the characteristic of the lathe , training time is short , with instant effect in view of operation and maintaining. As soon as the lathe transformed can fully utilize the existing condition Can fully utilize the existing ground , neednt need to construct the ground again like the thing that while buying the new equipment . can adopt the newest control technology But according to the development speed of technological innovation , improve the automatic level and efficiency of the production equipment in time, improve the quality of the equipment and grade, make the old lathe into the lathe of the current level. Fifth, choice of the numerical control system Numerical control system have three kind mainly , when transforming , should choose according to the concrete conditions. 5. A one that walk into the electrical machinery and pull turns on the ring system System this servo drive to walk into electrical machinery , power walk into electrical machinery , electric liquid pulse motor ,etc. mainly. The ones that are sent by the numerical control system are entered to the order pulse, after urging the circuit to control and power amplification, is it walk into electrical machinery rotate , through vice guide screw urge and carry out the part while being vice with ball gear wheel have to make. So long as control quantity , frequency , order of pulse and set up an electric circuit order , can is it carry out displacement amount , speed and sport direction , part of sport to control. The system need actual position and speed had to examine feedback the input end, so is it hold ring system to call it, system this displacement precision is it walk into precision of angle displacement of electrical machinery to decide by mainly, gear wheel guide screw ,etc. section, transmission of component from precision, so systematic displacement relatively low in precision This system is of simple structure, debug and maintain it conveniently, it is reliable to work, with low costs, easy to repack successfully. Asynchronous motor or direct current machine pull, grating measure feedback close the numerical control system of the ring This system and difference of making ring system are: Measure by grating , reaction synchronizer ,etc. position device examine actual position feedback signal that have, compare with setting value at any time, enlarge and vary the difference of the two, drive the executive body, by moving towards the direction of dispelling the deviation for the speed definitely, until giving definitely the position and real position feedbacked Difference equal zero. Close ring enter give system at structure than turn on ring is it give system to be complicated to enter , have higher costs even, require the environmental room temperature tightly. Design and debug than hold ring to be system difficult. Can obtain than make ring is it give system high precision to enter , fast speed, drive the more powerful characteristic index . But according to the specification requirement of the products , determine whether to adopt this kind of system or not. Pay / pull by direct current servo electrical machinery, half-closed ring numerical control system that encoder feedback Half-closed ring system measure component installation spread moveable piece in the middle , is it carry out position of part to measure indirectly. It can only compensate the errors of some components within the systematic cycle , so, its precision is lower than to close the precision of the ring system, but structure and debugging of it close ring to be system simple relatively. Measure angle displacement component and speed measure component and servo electrical machinery is it consider position measure installation issue of device to need at making one whole. Present manufacturer which produce company of the numerical control system many, such as Company , Company , FANUC of Japan , , SIEMENS of Germany , foreign famous company; Such as Company , Beijing spaceflight lathe numerical control systematic group company , Central China numerical control company , Shenyang top-grade numerical control national project research center , Mount Qomolangma of China , domestic corporation. Choose numerical control lathe want various kinds of precision that up to , urge power and users demand of electrical machinery after the transformation according to numerical control mainly at the system Sixth, numerical control the main mechanical part refits the discussion of transforming A new numerical control lathe , should reach in the design: There is high quiet dynamic rigidity ; The coefficient of friction between the vice sport is small, the transmission has no interval ; The power is large; Easy to operate and maintenance. Should try ones best to reach above-mentioned demands at the time of the numerical control transformation of the lathe . Cant is it is it meet the requirement of numerical control lathe right away to link numerical control device and ordinary lathe together to think, should go on corresponding transformation make their reach certain designing requirement to main part also, purpose of transforming that could be expected. Slip the guide pair To numerical control lathe, the guide is besides should have ordinary lathes to lead the precision and craft ing, still there should the good one that is able to bear rubing , wearing and tearing characteristic , reduce the causing death area because of rubing obstruction. There should be enough rigidity at the same time, in order to reduce the impact on machining accuracy out of shape of guides, there should rational guides that are protected and lubricated. The gear wheel of the general lathe concentrates on main shaft case and gearbox mainly. In order to guarantee the precision of transmission, the precision of gear wheel used at the numerical control lathe is higher than the ordinary lathe in grade . Can is it have interval transmission to reach at structure, therefore when transforming, lathe main gear wheel must meet demand , numerical control of lathe, so as to ensure the machining accuracy of the lathe . Slip the guide screw and ball guide screw. The guide screw transmission concerns the precision of drive chain directly. Exertion of guide screw depend on precision to process piece require and pull torsion not to require mainly. Can be adopted and slipped the guide screw while expecting much by a precision of processing, but should check the wearing and tearing situation of the original guide screw , if pitch error and pitch error match the nut interval totally. General situation slip guide screw should lower than 6 , nut interval too big to change nut. Is it slip guide screw relative guide screw price relatively low ball to adopt, but difficult to meet precision high part process. Ball guide screw friction loss light , with high efficiency, transmission its efficiency above 90% very; The precision is high , longe-lived; The moment is close while starting the moment and movement, can reduce the electrical machinery and start the moment . So can meet the more high-accuracy part and process the demand . Safe protection It is necessary if safe. It cant ignore to take the corresponding measure according to the actual conditions in the transformation of the lathe. The vice ball guide screw is the accurate component , prevent the dust especially smear metal and hard sand one strictly from entering and rolling dish while working. Can add the protection cover of whole iron plate on the vertical guide screw. Heavy to tow board and slip two terminal surface that guide exposed to is it seal kind to want , prevent hard quality foreign matter , particle of form from is it slip surface damage guide to enter definitely. Make the overall development strategy which accords with the Chinas actual conditions, establish the development path in line with international standards, technology and development of industry essential to 21st century of our country numerical control. This text is in the analysis on numerical control technology and industrys development trend, carry on the domain existing problem of numerical control of our country on the foundation of research, have carried on the discussion to the technology of numerical control of our country and approach to development of the industry in the 21st century, propose regarding scientific and technical innovation as the guide, regard commercializing as the backbone , regard managing and marketting as the focal point, is it for backing , insist sustainable overall development strategy of development path to serve with technical support. On this basis , have studied the concrete technological way to develop new-type numerical control system , numerical control function part , numerical control lathe complete machine ,etc. We hope sincerely , scientific and technological circle , industrial circle and education circle of our country work in concert, get hold of the rare opportunity that the kownledge economy brings to us, meet the severe challenge brought in competition globalization, arranging ago in order to make technology and industry of numerical control of our country more competitive in the world in the 21st century, make the economy of our country continue keeping the powerful growth momentum making joint efforts to struggle。数控技术的发展1、数控系统发展简史及趋势 1946年诞生了世界上第一台电子计算机，这表明人类创造了可增强和部分代替脑力劳动的工具。它与人类在农业、工业社会中创造的那些只是增强体力劳动的工具相比，起了质的飞跃，为人类进入信息社会奠定了基础。 1.1、数控（NC）阶段 早期计算机的运算速度低，对当时的科学计算和数据处理影响还不大，但不能适应机床实时控制的要求。人们不得不采用数字逻辑电路“搭”成一台机床专用计算机作一、数控系统发展简史及趋势 1946年诞生了世界上第一台电子计算机，这表明人类创造了可增强和部分代替脑力劳动的工具。它与人类在农业、工业社会中创造的那些只是增强体力劳动的工具相比，起了质的飞跃，为人类进入信息社会奠定了基础1.1、数控（NC）阶段（19521970年）早期计算机的运算速度低，对当时的科学计算和数据处理影响还不大，但不能适应机床实时控制的要求。人们不得不采为数控系统，被称为硬件连接数控（HARD-WIRED NC），简称为数控（NC）。随着元器件的发展，这个阶段历经1952年的第一代电子管；1959年的第二代晶体管；1965年的第三代小规模集成电路。 1.2、计算机数控（CNC）阶段（1970年现在） 到1970年，通用小型计算机业已出现并成批生产。于是将它移植过来作为数控系统的核心部件，从此进入了计算机数控（CNC）阶段（把计算机前面应有的“通用”两个字省略了）。到1971年，美国INTEL公司在世界上第一次将计算机的两个最核心的部件运算器和控制器，采用大规模集成电路技术集成在一块芯片上，称之为微处理器（MICROPROCESSOR），又可称为中央处理单元（简称CPU）。 到1974年微处理器被应用于数控系统。这是因为小型计算机功能太强，控制一台机床能力有富裕（故当时曾用于控制多台机床，称之为群控），不如采用微处理器经济合理。而且当时的小型机可靠性也不理想。早期的微处理器速度和功能虽还不够高，但可以通过多处理器结构来解决。由于微处理器是通用计算机的核心部件，故仍称为计算机数控。 到了1990年，PC机（个人计算机，国内习惯称微机）的性能已发展到很高的阶段，可以满足作为数控系统核心部件的要求。数控系统从此进入了基于PC的阶段。 总之，计算机数控阶段也经历了三代。即1970年的第四代小型计算机；1974年的第五代微处理器和1990年的第六代基于PC（国外称为PC-BASED）。 还要指出的是，虽然国外早已改称为计算机数控（即CNC）了，而我国仍习惯称数控（NC）。所以我们日常讲的“数控”，实质上已是指“计算机数控”了。 1.3、数控未来发展的趋势 1.3.1继续向开放式、基于PC的第六代方向发展 基于PC所具有的开放性、低成本、高可靠性、软硬件资源丰富等特点，更多的数控系统生产厂家会走上这条道路。至少采用PC机作为它的前端机，来处理人机界面、编程、联网通信等问题，由原有的系统承担数控的任务。PC机所具有的友好的人机界面，将普及到所有的数控系统。远程通讯，远程诊断和维修将更加普遍。 1.3.2向高速化和高精度化发展 这是适应机床向高速和高精度方向发展的需要。 1.3.3向智能化方向发展 随着人工智能在计算机领域的不断渗透和发展，数控系统的智能化程度将不断提高。 （1）应用自适应控制技术 数控系统能检测过程中一些重要信息，并自动调整系统的有关参数，达到改进系统运行状态的目的。 （2）引入专家系统指导加工 将熟练工人和专家的经验，加工的一般规律和特殊规律存入系统中，以工艺参数数据库为支撑，建立具有人工智能的专家系统。 （3）引入故障诊断专家系统 （4）智能化数字伺服驱动装置 可以通过自动识别负载，而自动调整参数，使驱动系统获得最佳的运行。2、机床数控化改造的必要性 2.1、微观看改造的必要性 从微观上看，数控机床比传统机床有以下突出的优越性，而且这些优越性均来自数控系统所包含的计算机的威力。 2.1.1 可以加工出传统机床加工不出来的曲线、曲面等复杂的零件。 由于计算机有高超的运算能力，可以瞬时准确地计算出每个坐标轴瞬时应该运动的运动量，因此可以复合成复杂的曲线或曲面。 2.1.2 可以实现加工的自动化，而且是柔性自动化，从而效率可比传统机床提高37倍。 由于计算机有记忆和存储能力，可以将输入的程序记住和存储下来，然后按程序规定的顺序自动去执行，从而实现自动化。数控机床只要更换一个程序，就可实现另一工件加工的自动化，从而使单件和小批生产得以自动化，故被称为实现了“柔性自动化”。 2.1.3 加工零件的精度高，尺寸分散度小，使装配容易，不再需要“修配”。 2.1.4 可实现多工序的集中，减少零件 在机床间的频繁搬运。 2.1.5 拥有自动报警、自动监控、自动补偿等多种自律功能，因而可实现长时间无人看管加工。 2.1.6 由以上五条派生的好处。 如：降低了工人的劳动强度，节省了劳动力（一个人可以看管多台机床），减少了工装，缩短了新产品试制周期和生产周期，可对市场需求作出快速反应等等。以上这些优越性是前人想象不到的，是一个极为重大的突破。此外，机床数控化还是推行FMC（柔性制造单元）、FMS（柔性制造系统）以及CIMS（计算机集成制造系统）等企业信息化改造的基础。数控技术已经成为制造业自动化的核心技术和基础技术。 2.2、宏观看改造的必要性 从宏观上看，工业发达国家的军、民机械工业，在70年代末、80年代初已开始大规模应用数控机床。其本质是，采用信息技术对传统产业（包括军、民机械工业）进行技术改造。除在制造过程中采用数控机床、FMC、FMS外，还包括在产品开发中推行CAD、CAE、CAM、虚拟制造以及在生产管理中推行MIS（管理信息系统）、CIMS等等。以及在其生产的产品中增加信息技术，包括人工智能等的含量。由于采用信息技术对国外军、民机械工业进行深入改造（称之为信息化），最终使得他们的产品在国际军品和民品的市场上竞争力大为增强。而我们在信息技术改造传统产业方面比发达国家约落后20年。如我国机床拥有量中，数控机床的比重（数控化率）到1995年只有1.9%，而日本在1994年已达20.8%，因此每年都有大量机电产品进口。这也就从宏观上说明了机床数控化改造的必要性。 3、机床与生产线数控化改造的市场 3.1、机床数控化改造的市场 我国目前机床总量380余万台，而其中数控机床总数只有11.34万台，即我国机床数控化率不到3%。近10年来，我国数控机床年产量约为0.60.8万台，年产值约为18亿元。机床的年产量数控化率为6%。我国机床役龄10年以上的占60%以上；10年以下的机床中，自动/半自动机床不到20%，FMC/FMS等自动化生产线更屈指可数（美国和日本自动和半自动机床占60%以上）。可见我们的大多数制造行业和企业的生产、加工装备绝大数是传统的机床，而且半数以上是役龄在10年以上的旧机床。用这种装备加工出来的产品普遍存在质量差、品种少、档次低、成本高、供货期长，从而在国际、国内市场上缺乏竞争力，直接影响一个企业的产品、市场、效益，影响企业的生存和发展。所以必须大力提高机床的数控化率。 3.2、进口设备和生产线的数控化改造市场 我国自改革开放以来，很多企业从国外引进技术、设备和生产线进行技术改造。据不完全统计，从19791988年10年间，全国引进技术改造项目就有18446项，大约165.8亿美元。 这些项目中，大部分项目为我国的经济建设发挥了应有的作用。但是有的引进项目由于种种原因，设备或生产线不能正常运转，甚至瘫痪，使企业的效益受到影响，严重的使企业陷入困境。一些设备、生产线从国外引进以后，有的消化吸收不好，备件不全，维护不当，结果运转不良；有的引进时只注意引进设备、仪器、生产线，忽视软件、工艺、管理等，造成项目不完整，设备潜力不能发挥；有的甚至不能启动运行，没有发挥应有的作用；有