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汽车左转向节的机械加工工艺规程及工艺夹具设计(全套含CAD图纸)

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下载后文件包含有 CAD 图纸和说明书,咨询 Q 197216396 或 119709851摘 要本次毕业设计的题目是 CA141 左转向节规程及工装设计。我主要需要完成的包括加工工艺的安排以及两种专用机床夹具设计。为了保证加工零件的精度同时节约成本和缩短加工周期以及提高加工效率,那么一个良好的工艺安排以及专用夹具的设计就是必不可少的了。在工艺的安排上不但要考虑合理的加工要求还要考虑到操作者以及加工机械的安全。同时夹具的设计上也要考虑到使用的安全性和经济性以及安装和拆卸上的方便性。设计一个良好的工艺工装安排路线那么必须要经过对加工件的详细分析以及周密的考虑后才能得出。所以分析问题是解决问题的关键,同时还要反复的调整,来寻求最好的一个路线。这样才能让工艺路线更加的完美,才能保证工件的加工精度和加工效率以及节约材料。关键词 转向节;加工工艺;专用夹具;加工精度;工艺路线下载后文件包含有 CAD 图纸和说明书,咨询 Q 197216396 或 119709852AbstractThe graduation design is the subject of CA141 cars left steering process tooling. I mainly need to complete including Processing craft arrangement as well as special-purpose drill jig design.In order to guarantee the processing components the precision Simultaneously saves cost and the reduction processing cycle as well as the enhancement processing efficiency, Then a good craft arrangement as well as unit clamps design was essential. Not only in the craft arrangement must consider that the reasonable processing request also needs to consider the operator as well as processes machinerys security. Simultaneously jigs design also needs to consider the use in secure and efficient as well as the installment and the disassemblage conveniences. Designs a good craft work clothes arrangement route that to probably pass through to the job multianalysis,After as well as thorough consideration, can obtain. Therefore the analysis question solves the question key, meanwhile must the repeated adjustment, Seeks a best route. Seeks a best route to be able to let craft route even more perfect like this, can guarantee that the work piece the working accuracy and the processing efficiency as well as save the material.Key word Steering ; Processing craft; Unit clamp; Working accuracy ; Craft route下载后文件包含有 CAD 图纸和说明书,咨询 Q 197216396 或 119709853目 录摘要 Abstract 绪论 11 零件的分析 2 1.1 零件的作用 21.2 零件的工艺分析 31.2.1 轴颈部分 31.2.2 法兰部分 41.2.3 叉架部分 41.2.4 位置精度要求 42 工艺规程设计 62.1 确定毛坯的制造形式 62.2 基面的选择 62.2.1 定位基准的选择 62.2.2 粗基准的选择 62.2.6 精基准的选择 72.3 工艺规程的设计原则 72.4 制定工艺路线 82.5 机械加工余量、工序尺寸及毛坯尺寸的确定 122.6 确定切削用量及基本工时 153 夹具设计 313.1 拉床专用夹具设计 313.1.1 问题的提出 313.1.2 夹具设计 31下载后文件包含有 CAD 图纸和说明书,咨询 Q 197216396 或 1197098543.2 钻模夹具设计 333.2.1 问题的提出 333.2.2 夹具设计 33总结 37致谢 38参考文献 39下载后文件包含有 CAD 图纸和说明书,咨询 Q 197216396 或 119709855下载后文件包含有 CAD 图纸和说明书,咨询 Q 197216396 或 119709856下载后文件包含有 CAD 图纸和说明书,咨询 Q 197216396 或 119709857下载后文件包含有 CAD 图纸和说明书,咨询 Q 197216396 或 119709858绪 论近 20 年来,随着科学与技术的迅速发展,特别是计算机科学与技术的迅速发展和广泛应用,国外在发展自动化方面也进入了一个新的时期,出现了许多新的工具和软件。自动化开始向柔性化发展,进入中小批量生产领域。在制定工艺过程中,为便于组织生产、安排计划和均衡机床的负荷,常将工艺划分为若干个工序。划分工序时有两个不同的原则,即工序的集中和工序的分散。工序集中的特点是:一是有利于采用自动化程度较高的高效率机床和工艺设备,生产效率高;二是工序数少,设备数少,可相应减少操作工人数和生产面积;三是工件的装夹次数少不但缩短辅助时间,而且由于一次装夹中可加工许多表面,有利于保证各表面之间的相互位置精度。工序分散的特点是:一是所用机床和工艺设备简单,易于调整;二是对操作工人的技术水平要求不高;三是工序数多,设备数多,操作工人多,占用生产面积大。对机床夹具的基本要求是:一是稳定地保证工件的加工精度;二是提高机械加工的劳动生产率;三是结构简单,有良好的结构工艺性和劳动条件;三是应能降低工件的制造成本。简而言之,设计夹具时必须使加工质量、生产率、劳动条件和经济性等几方面达到辨证的统一。其中保证加工质量是最基本的要求。夹具设计的工作步骤为:一是研究原始材料,明确设计任务;二是考虑和确定夹具的结构方案,绘制结构草图(定位装置、夹紧装置等等) ;三是绘制夹具总图;四是确定并标注有关尺寸和夹具技术要求;五是绘制夹具零件图。此次设计的零件为 CA141 汽车左转向节工艺规程及工装设计。通过零件,分析了它的毛坯。在毛坯制造时的方法与原则,以及所选用的工艺等。本次设计总共分为两部分, 第一部分为工艺方面:主要包括零件的功用 , 结构特点, 加工零件表面的设计基准, 设计条件, 毛坯的选择, 各个工艺方案的比较与取舍, 确定机床与工艺装备, 填写工艺过程卡片。 第二部分主要为机床夹具设计:主要包括定位方案的确定, 定位元件的选取, 夹紧方案的选取等等。毕业设计是我们学完了大学的全部基础课程、专业基础课程以及专业课程并进行了生产实习以后进行的一次培养大学生的创新能力、实践能力和创业精神的重要实践环节,也是学生完成工程师基本训练的重要环节。同时也是我们对能力的一次真正的下载后文件包含有 CAD 图纸和说明书,咨询 Q 197216396 或 119709859锻炼,它能激发我们的创新意识,增强我们的动手和动脑的能力,它使我们的思维开阔,同时也让我们了解到如何把理论与实践相结合。其目的是培养学生综合运用所学专业和基础理论知识,独立解决本专业一般工程技术问题能力,树立正确的设计思想和工作作风。本次毕业设计是理论与实践的结合,目的在于检验学生大学四年的学习成果,培养我们综合运用所学理论知识去分析和解决工程技术问题的能力,使学生建立正确设计思想和设计方法,通过毕业设计进一步巩固、深化计算机制图之基,即基本理论、基本概念、基本技能。毕业设计的范围涉及大学四年所学的专业基础课及专业课、选修课内容,知识含量大、跨度仅限于机械制造范围。设计题目由指导教师提供,其设计内容均由学生自行编排,在巩固专业知识之余意在培养思考、解决问题的能力,同时提倡创新精神。就个人而言,我通过这次毕业设计一方面能进一步培养我独立思考的能力,另一方面能提高我与同学们互助协作的能力,为以后工作打下良好基础,为伟大祖国建设贡献我的力量。由于本人能力有限,经验不足,设计过程中有不足之处,希望各位老师给予指教。我主要的是完成工艺的安排和夹具的设计,夹具是加工过程中最重要的一个组成部分,很多工件由于形状和加工要求等等特殊的原因必须要使工件很好的定位后才能进行加工,所以也就出现了夹具以及专用的夹具。下载后文件包含有 CAD 图纸和说明书,咨询 Q 197216396 或 11970985101 零件的分析1.1 零件的作用转向节(羊角)是汽车转向桥上的主要零件之一,转向节的功用是承受汽车前部载荷,支承并带动前轮绕主销转动而使汽车转向。在汽车行驶状态下,它承受着多变的冲击载荷,因此,要求其具有很高的强度。转向节形状比较复杂,集中了轴、套、盘环、叉架等四类零件的结构特点,主要由支承轴颈、法兰盘、叉架三大部分组成。支承轴颈的结构形状为阶梯轴,其结构特点是由同轴的外圆柱面、圆锥面、螺纹面,以及与轴心线垂直的轴肩、过渡圆角和端面组成的回转体;法兰盘包括法兰面、均布的连接螺栓通孔和转向限位的螺纹孔;叉架是由转向节的上、下耳和法兰面构成叉架形体的。零件的叉头部位上有两个 mm 的孔,用以连接转向节主销和滚子轴承,41+0.0390使前轮可以绕主销偏转一定角度进而起到转向的作用。法兰面上有 6 的螺钉孔以及 2 M16 1.5-6H 的螺纹孔,通过螺钉12.3+0.0240 将法兰面与制动器的制动盘连接在一起。转向节的轴颈通过轮毂轴承与轮毂相连接内开档部位 mm 的轴承窝,用以与汽车前桥大梁连接,实现转向动作。叉85+0.30架部位带键槽的两个锥形孔用以连接,上孔与转向节臂连接,传递转向时所需的力和扭矩,下孔与梯形臂相连接,通过横向拉杆进而于右侧转向节相连接,左右转向节协调,实现同步转向。转向节在整个机械转向系统中的位置如下图。英文资料High-speed millingHigh-speed machining is an advanced manufacturing technology, different from the traditional processing methods. The spindle speed, cutting feed rate, cutting a small amount of units within the time of removal of material has increased three to six times. With high efficiency, high precision and high quality surface as the basic characteristics of the automobile industry, aerospace, mold manufacturing and instrumentation industry, such as access to a wide range of applications, has made significant economic benefits, is the contemporary importance of advanced manufacturing technology. For a long time, people die on the processing has been using a grinding or milling EDM (EDM) processing, grinding, polishing methods. Although the high hardness of the EDM machine parts, but the lower the productivity of its application is limited. With the development of high-speed processing technology, used to replace high-speed cutting, grinding and polishing process to die processing has become possible. To shorten the processing cycle, processing and reliable quality assurance, lower processing costs.1 One of the advantages of high-speed machiningHigh-speed machining as a die-efficient manufacturing, high-quality, low power consumption in an advanced manufacturing technology. In conventional machining in a series of problems has plagued by high-speed machining of the application have been resolved.1.1 Increase productivity High-speed cutting of the spindle speed, feed rate compared withtraditional machining, in the nature of the leap, the metal removal rate increased 30 percent to 40 percent, cutting force reduced by 30 percent, the cutting tool life increased by 70% . Hardened parts can be processed, a fixture in many parts to be completed rough, semi-finishing and fine, and all other processes, the complex can reach parts of the surface quality requirements, thus increasing the processing productivity and competitiveness of products in the market.1.2 Improve processing accuracy and surface quality High-speed machines generally have high rigidity and precision, and other characteristics, processing, cutting the depth of small, fast and feed, cutting force low, the workpiece to reduce heat distortion, and high precision machining, surface roughness small. Milling will be no high-speed processing and milling marks the surface so that the parts greatly enhance the quality of the surface. Processing Aluminum when up Ra0.40.6um, pieces of steel processing at up to Ra0.2 0.4um.1.3 Cutting reduce the heat Because the main axis milling machine high-speed rotation, cutting a shallow cutting, and feed very quickly, and the blade length of the workpiece contacts and contact time is very short, a decrease of blades and parts of the heat conduction. High-speed cutting by dry milling or oil cooked up absolute (mist) lubrication system, to avoid the traditional processing tool in contact with the workpiece and a lot of shortcomings to ensure that the tool is not high temperature under the conditions of work, extended tool life.1.4 This is conducive to processing thin-walled partsHigh-speed cutting of small cutting force, a higher degree of stability, Machinable with high-quality employees compared to the company may be very good, but other than the companys employees may Suanbu Le outstanding work performance. For our China practice, we use the models to determine the method of staff training needs are simple and effective. This study models can be an external object, it can also be a combination of internal and external. We must first clear strategy for the development of enterprises. Through the internal and external business environment and organizational resources, such as analysis, the future development of a clear business goals and operational priorities. According to the business development strategy can be compared to find the business models, through a comparative analysis of the finalization of business models. In determining business models, a, is the understanding of its development strategy, or its market share and market growth rate, or the staff of the situation, and so on, according to the companies to determine the actual situation. As enterprises in different period of development, its focus is different, which means that enterprises need to invest the manpower and financial resources the focus is different. So in a certain period of time, enterprises should accurately selected their business models compared with the departments and posts, so more practical significance, because the business models are not always good, but to compare some aspects did not have much practical significance, Furthermore This can more fully concentrate on the business use of limited resources. Identify business models, and then take the enterprise of the corresponding departments and staff with the business models for comparison, the two can be found in the performance gap, a comparative analysis to find reasons, in accordance with this business reality, the final identification of training needs. The cost of training is needed, if not through an effective way to determine whether companies need to train and the training of the way, but blind to training, such training is difficult to achieve the desired results. A comparison only difference between this model is simple and practical training.1.5 Can be part of some alternative technology, such as EDM, grinding high intensity and high hardness processingHigh-speed cutting a major feature of high-speed cutting machine has the hardness of HRC60 parts. With the use of coated carbide cutter mold processing, directly to the installation of a hardened tool steel processing forming, effectively avoid the installation of several parts of the fixture error and improve the parts of the geometric location accuracy. In the mold of traditional processing, heat treatment hardening of the workpiece required EDM, high-speed machining replace the traditional method of cutting the processing, manufacturing process possible to omit die in EDM, simplifying the processing technology and investment costs . High-speed milling in the precincts of CNC machine tools, or for processing centre, also in the installation of high-speed spindle on the general machine tools. The latter not only has the processing capacity of general machine tools, but also for high-speed milling, a decrease of investment in equipment, machine tools increased flexibility. Cutting high-speed processing can improve the efficiency, quality improvement, streamline processes, investment and machine tool investment and maintenance costs rise, but comprehensive, can significantly increase economic efficiency.2 High-speed milling High-speed milling the main technical high-speed cutting technology is cutting the development direction of one of it with CNC technology, microelectronic technology, new materials and new technology, such as technology development to a higher level. High-speed machine tools and high-speed tool to achieve high-speed cutting is the prerequisite and basic conditions, in high-speed machining in the performance of high-speed machine tool material of choice and there are strict requirements. 2.1 High-speed milling machine in order to achieve high-speed machiningGeneral use of highly flexible high-speed CNC machine tools, machining centers, and some use a dedicated high-speed milling, drilling. At the same time a high-speed machine tool spindle system and high-speed feeding system, high stiffness of the main characteristics of high-precision targeting and high-precision interpolation functions, especially high-precision arc interpolation function. High-speed machining systems of the machine a higher demand, mainly in the following areas:General use of highly flexible high-speed CNC machine tools, machining centers, and some use a dedicated high-speed milling, drilling. At the same time a high-speed machine tool spindle system and high-speed feeding system, high stiffness of the main characteristics of high-precision targeting and high-precision interpolation functions, especially high-precision arc interpolation function. High-speed machining systems of the machine a higher demand, mainly in the following areas: High-speed milling machine must have a high-speed spindle, the spindle speed is generally 10000 100000 m / min, power greater than 15 kW. But also with rapid speed or in designated spots fast-stopping performance. The main axial space not more than 0 .0 0 0 2 m m. Often using high-speed spindle-hydrostatic bearings, air pressure-bearing, mixed ceramic bearings, magnetic bearing structure of the form. Spindle cooling general use within the water or air cooled. High-speed processing machine-driven system should be able to provide 40 60 m / min of the feed rate, with good acceleration characteristics, can provide 0.4 m/s2 to 10 m/s2 acceleration and deceleration. In order to obtain good processing quality, high-speed cutting machines must have a high enough stiffness. Machine bed material used gray iron, can also add a high-damping base of concrete, to prevent cutting tool chatter affect the quality of processing. A high-speed data transfer rate, can automatically increase slowdown. Processing technology to improve the processing and cutting tool life. At present high-speed machine tool manufacturers, usually in the general machine tools on low speed, the feed of the rough and then proceed to heat treatment, the last in the high-speed machine on the half-finished and finished, in improving the accuracy and efficiency at the same time, as far as possible to reduce processing Cost.2.2 High-speed machining tool High-speed machining tool is the most active one of the important factors, it has a direct impact on the efficiency of processing, manufacturing costs and product processing and accuracy. Tool in high-speed processing to bear high temperature, high pressure, friction, shock and vibration, such as loading, its hardness and wear-resistance, strength and toughness, heat resistance, technology and economic performance of the basic high-speed processing performance is the key One of the factors. High-speed cutting tool technology development speed, the more applications such as diamond (PCD), cubic boron nitride (CBN), ceramic knives, carbide coating, (C) titanium nitride Carbide TIC (N) And so on. CBN has high hardness, abrasion resistance and the extremely good thermal conductivity, and iron group elements between the great inertia, in 1300 would not have happened significant role in the chemical, also has a good stability. The experiments show that with CBN cutting toolHRC35 67 hardness of hardened steel can achieve very high speed. Ceramics have good wear resistance and thermal chemical stability, its hardness, toughness below the CBN, can be used for processing hardness of HRC 5 0 parts. Carbide Tool good wear resistance, but the hardness than the low-CBN and ceramics. Coating technology used knives, cutting tools can improve hardness and cutting the rate, for cutting HRC40 50 in hardness between the workpiece. Can be used to heat-resistant alloys, titanium alloys, hightemperature alloy, cast iron, Chungang, aluminum and composite materials of high-speed cutting Cut, the most widely used. Precision machining non-ferrous metals or non-metallic materials, or the choice of polycrystalline diamond Gang-coated tool.2.3 High-speed processing technology High-speed cutting technology for high-speed machining is the key. Cutting Methods misconduct, will increase wear tool to less than high-speed processing purposes. Only high-speed machine tool and not a good guide technology, high-speed machining equipment can not fully play its role. In high-speed machining, should be chosen with milling, when the milling cutter involvement with the workpiece chip thickness as the greatest, and then gradually decreased. High-speed machining suitable for shallow depth of cut, cutting depth of not more than 0.2 mm, to avoid the location of deviation tool to ensure that the geometric precision machining parts. Ensure that the workpiece on the cutting constant load, to get good processing quality. Cutting a single high-speed milling path-cutting mode, try not to interrupt the process and cutting tool path, reducing the involvement tool to cut the number to be relatively stable cutting process. Tool to reduce the rapid change to, in other words when the NC machine tools must cease immediately, or Jiangsu, and then implement the next step. As the machine tool acceleration restrictions, easy to cause a waste of time, and exigency stop or radical move would damage the surface accuracy. In the mold of high-speed finishing, in each Cut, cut to the workpiece, the feed should try to change the direction of a curve or arc adapter, avoid a straight line adapter to maintain the smooth process of cutting.3 Die in high-speed milling processing of Milling as a highly efficient high-speed cutting of the new method,in Mould Manufacturing has been widely used. Forging links in the regular production model, with EDM cavity to be 12 15 h, electrodes produced 2 h. Milling after the switch to high-speed, high-speed milling cutter on the hardness of HRC 6 0 hardened tool steel processing. The forging die processing only 3 h20min, improve work efficiency four to five times the processing surface roughness of Ra0.5 0.6m, fully in line with quality requirements.High-speed cutting technology is cutting technology one of the major developments, mainly used in automobile industry and die industry, particularly in the processing complex surface, the workpiece itself or knives rigid requirements of the higher processing areas, is a range of advanced processing technology The integration, high efficiency and high quality for the people respected. It not only involves high-speed processing technology, but also including high-speed processing machine tools, numerical control system, high-speed cutting tools and CAD / CAM technology. Die-processing technology has been developed in the mold of the manufacturing sector in general, and in my application and the application of the standards have yet to be improved, because of its traditional processing with unparalleled advantages, the future will continue to be an inevitable development of processing technology Direction.4 Numerical control technology and equipping development trend and countermeasureEquip the engineering level, level of determining the whole national economy of the modernized degree and modernized degree of industry, numerical control technology is it develop new developing new high-tech industry and most advanced industry to equip (such as information technology and his industry, biotechnology and his industry, aviation, spaceflight, etc. national defense industry) last technology and getting more basic most equipment. Marx has ever said “the differences of different economic times, do not lie in what is produced, and lie in how to produce, produce with some means of labor “. Manufacturing technology and equipping the most basic means of production that are that the mankind produced the activity, and numerical control technology is nowadays advanced manufacturing technology and equips the most central technology. Nowadays the manufacturing industry all around the world adopts numerical control technology extensively, in order to improve manufacturing capacity and level, improve the adaptive capacity and competitive power to the changeable market of the trends. In addition every industrially developed country in the world also classifies the technology and numerical control equipment of numerical control as the strategic materials of the country, not merely take the great measure to develop ones own numerical control technology and industry, and implement blockading and restrictive policy to our country in view of “ high-grade, precision and advanced key technology of numerical control “ and equipping. In a word, develop the advanced manufacturing technology taking numerical control technology as the core and already become every world developed country and accelerate economic development in a more cost-effective manner, important way to improve the overall national strength and national position. Numerical control technology is the technology controlled to mechanical movement and working course with digital information, integrated products of electromechanics that the numerical control equipment is the new technology represented by numerical control technology forms to the manufacture industry of the tradition and infiltration of the new developing manufacturing industry, namely the so-called digitization is equipped, its technological range covers a lot of fields: (1)Mechanical manufacturing technology; (2)Information processing, processing, transmission technology; (3)Automatic control technology; (4)Servo drive technology; (5)Technology of the sensor; (6)Software engineering ,etc. Development trend of a numerical control technologyThe application of numerical control technology has not only brought the revolutionary change to manufacturing industry of the tradition, make the manufacturing industry become the industrialized symbol , and with the constant development of numerical control technology and enlargement of the application, the development of some important trades (IT , automobile , light industry , medical treatment ,etc. ) to the national economy a
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本文标题:汽车左转向节的机械加工工艺规程及工艺夹具设计(全套含CAD图纸)
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