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挖掘机工作装置液压系统设计【17张CAD图纸和说明书】

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挖掘机工作装置液压系统设计【17张CAD图纸和说明书】.rar

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关键词：: 挖掘机工作装置液压系统设计 17 cad 图纸以及说明书仿单

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1 前言……………………………………………………………………1

1.1 挖掘机间介…………………………………………………………1

1.2 国内外研究现状及发展动态………………………………………2

1.3 本设计的研究内容…………………………………………………5

2 液压挖掘机结构与工作原理…………………………………………7

2.1 液压挖掘机整机性能………………………………………………7

2.2 液压挖掘机结构……………………………………………………8

2.3 液压挖掘机传动原理……………………………………………10

3 液压挖掘机工况分析及液压系统设计方案的确定………………12

3.1 液压挖掘机的工况………………………………………………12

3.2 挖掘机液压系统的设计要求……………………………………17

3.3 挖掘机液压系统的分析…………………………………………19

3.4 液压系统方案拟订………………………………………………20

4 液压系统的设计……………………………………………………21

4.1 液压系统方案及参数确定………………………………………21

4.2 执行元件液压缸及系统压力的初选……………………………22

4.3 计算工作装置铲斗液压缸的主要尺寸…………………………23

4.4 液压系统原理图的制定…………………………………………26

5 液压元件的选择与专用件的设计…………………………………31

5.1 液压泵的选择和泵的参数的计算………………………………31

5.2 柴油发动机的选择………………………………………………33

5.3 液压阀的选择……………………………………………………33

5.4 其他液压元件的选择……………………………………………36

5.5 油箱容量的确定…………………………………………………38

6 压系统性能验算……………………………………………………40

6.1 液压系统压力损失………………………………………………40

6.2 液压系统的发热温升计算………………………………………41

总结………………………………………………………………46

参考文献………………………………………………………………47

致　谢………………………………………………………………49

内容提要

挖掘机作为我国工程机械的主力机种，被广泛应用于各种各样的施工作业中。挖掘机产品的核心技术就是液压系统设计，由于挖掘机的工作条件恶劣，要求实现的动作复杂，于是它对液压系统的设计提出了很高的要求，其液压系统也是工程机械液压系统中最为复杂的。因此，对挖掘机液压系统的分析设计对推动我国挖掘机发展具有十分重要的意义。

在搜集了国内外挖掘机液压系统相关资料的基础上，了解了挖掘机液压系统的发展历史，并对挖掘机液压系统的技术发展动态进行了分析总结。论文对挖掘机的各种工况进行了分析，系统总结了挖掘机液压系统的设计要求。根据挖掘机液压系统的设计要求，论文中采用通用多路阀，配以专用控制阀和简单的电子控制系统，设计了一套适合我国生产制造的LS恒功率控制单斗挖掘机液压系统。

本次毕业设计课题是WY200型液压挖掘机。课题以企业为依托。小型挖掘机由多个系统组成，包括液压系统，传动系统，操纵系统，工作装置，底架，转台，油箱，发动机安装等。本人的设计主要致力于分析和设计小型液压挖掘机工作装置的液压系统。本课题选择了国内的质量和技术性能都接近设计要求的16~20t挖掘机作为基型，并在此基础上研究了国外的先进机型，设计出我们挖掘机的液压系统方按图，总体装配图以及相应的部件图和零件图。图纸基本采用Auto CAD二维软件绘图。本液压挖掘机的优点是采用伺服先导操纵系统，造型美观，具备挖掘，抓物，钻孔，推土，清沟和破碎等功能。平台可360°旋转，性能可靠，操作舒适，可广泛应用于建筑，市政，供水，供气，供电农林建设等工程。

Summary

The excavator is a main consrtuctional machine，which is now widely used in various construction sites.The core technique of excavator is hydrau1ic technique. Becauseofthe bad working condition and conmplicated working movements of the excavatot，it has high requitements for its hydraulic system.Since the excavator’s hydraulic system is the most complicated one in all constructional machines ,the analysis and research of its hydrau1ic system make very important sens.

On the basis of comprehensive co11ection of re1ated information about the excavator’s hydraulic system at home and abroad，the main working conditions of the excavator are studied and the design requitments of its hydraulic system are systematically summarized. According to the design pressure compensated hydraulic system is creatively designed using general multiple until value equipped with special contol valve and electronic contor systems,which has useful reference value for the future research and development of the excavator’s hydraulic system in our country.

The name of this graduated task is “WY200 medium type hydraulic excavator”.This task is requested by company. My task is to analyze and design the hydraulic system of the medium type hydraulic excavator. This task choose the domestic excavator whose quality and character is most similar to our request as the basic type, further study the overseas advanced type. Then I designed projects of hydraulic system of our excavator,collectivity assemblage drawing and interrelated parts drawing, accessory drawing. All the blueprints drawn by the soft of AutoCAD. The strongpoint of this hydraulic excavator is used servo forerunner control system. It has beautiful sculpt. Beijing provided with the fuction of excavating, grappling, drilling, pushing, cleaning channel and crashing etc. 360°swwing plat roof,good quality, controlling comfortable, be widely used in construction,supply and city planning.

１　前言

液压挖掘机是一种多功能机械，目前被广泛应用于水利工程，交通运输，电力工程和矿山采掘等机械施工中，它在减轻繁重的体力劳动，保证工程质量。加快建设速度以及提高劳动生产率方面起着十分重要的作用。由于液压挖掘机具有多品种，多功能，高质量及高效率等特点，因此受到了广大施工作业单位的青睐。液压挖掘机的生产制造业也日益蓬勃发展。

挖掘机液压传动紧密地联系在一起，其发展主要以液压技术的应用为基础。由于挖掘机的工作条件恶劣，要求实现的动作很复杂，于是它对液压系统的设计提出了很高的要求，其液压系统也是工程机械液压系统中最为复杂的。因此，对挖掘机液压系统的分析设计已经成为推动挖掘机发展中的重要一环[1]。

1.1　挖掘机简介

挖掘机行业的发展历史久远，可以追溯到1840年。当时美国西部开发，进行铁路建设，产生了模仿人体构造，有大臂、小臂和手腕，能行走和扭腰类似机械手的挖掘机，它采用蒸汽机作为动力在轨道上行走。但是此后的很长时间挖掘机没有得到很大的发展，应用范围也只局限于矿山作业中。

导致挖掘机发展缓慢的主要原因是:其作业装置动作复杂，运动范围大，需要采用多自由度机构，古老的机械传动对它不太适合。而且当时的工程建设主要是国土开发，大规模的筑路和整修场地等，大多是大面积的水平作业，因此对挖掘机的应用相对较少，在一定程度上也限制了挖掘机的发展。

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内容简介：: 毕业设计（论文）任务书专业班级学生姓名学号课题名称挖掘机工作装置液压系统设计设计(论文)起止时间 2007 年 3 月 26 日至 200 7 年 6 月 8 日课题类型工程设计课题性质真实一、课题研究的目的与主要内容研究目的：设计多功能液压挖掘机的液压系统，驱动挖掘机完成多功能作业。与山河智能机械股份有限公司校企合作。学生在生产现场做毕业设计，全面提高综合设计能力，工程实践能力。主要内容： 1、对挖掘机进行结构分析。2、设计挖掘机工作装置的液压系统。3、绘制挖掘机的液压系统原理图。二、基本要求1、必须独立完成毕业设计工作。2、按制图标准设计多功能液压挖掘机液压系统图和有关零件的零件图，图纸比例 11，毕业设计图纸总工作量不少于 2 张零号图纸。3、按学院毕业设计的书写格式要求，撰写设计说明书，毕业设计说明书不少于 20000 字。4、每个学生应完成与毕业设计有关的 3000-5000 个文字的外文资料翻译, 译文要求准确,文字流畅。注：1、此表由指导教师填写，经各系、教研室主任审批生效；2、此表 1 式 3 份，学生、指导教师、教研室各 1 份。三、课题研究已具备的条件（包括实验室、主要仪器设备、参考资料）1、邵阳学院的实习工厂。2、机械与能源工程系机械设计实验室，数控加工中心实验室，主要仪器设备有：线切割加工机床，电火花成形加工机床，数控加工中心，类型较多的机械设计零件等。3、邵阳学院图书馆。3、主要参考资料：机械工程设计手册，期刊杂志工程机械。4、山河智能有限公司挖掘机装配车间实习、技术部资料查阅。四、设计（论文）进度表1、2007.3.262007.3.28 确定课题。1、2007.3.292007.4.4 搜集资料，完成开题报告。2、2007.4.52007.5.6 挖掘机结构的确定。 3、2007.4.262007.5.10 绘制多功能液压挖掘机液压系统图。4、2007.5.112007.5.25 外文资料翻译，撰写设计说明书。5、2007.5.262007.6.8 毕业设计文件打印、撰写答辩提纲准备答辩。五、教研室审批意见教研室主任（签名）年月日六、院（系）审批意见院（系）负责人（签名）单位（公章）年月日指导教师（签名）学生（签名）1Modern construction machinery industry of technical progressLarge-size mechanical mining excavator is used widely in international and domestic engineering construction and mining performance, and its property defines the efficiency much.Now because the international market is opened step step, how to promote the quality of excavator is the key that a factory reinforces its competing force.In our country，the designing elevation and production quality on excavator can not keep up with international advanced technology applying on excavator.Now the advanced technology has already applied advanced designing method on excavator designing，such as electronic simulating theory，dynamic design， reliability design and so on.But in our country ,the most excavator design has still applied the traditional design method ,the modern design method has not began to be actually applied .The prime display is that the capability of self-design is not enough and the basic work has not done perfectly especially the excavator kinetics .The construct of excavator is very complex and the multiple movers often work simultaneously.at the same time its working environment is very bad and the eternal load varies randomly.As a result ,when designing the new product of excavator ,in order to ensure the performance safety，the designer not only has the basic theory analysis on static load computing ,but also do necessary work about the kinetics of mechanism to qualify the dynamic reliability in the period of designing .Trough the kinetic analysis ,the load property of all the elements in excavator can be decided so as to design reliable product .From the 1980s of the 20th century to the beginning of this century. Chinese and foreign engineering machinery technology products come from a maturity period of modernization along with a new technological revolution, Mechanical engineering products integrated technology to a new level. Electronic technology, micro-computer, sensors, electro-hydraulic servo control system integration and transformation of the traditional mechanical engineering products, Computer-aided design and computer-aided 2manufacturing and computer-aided management of construction machinery and equipment manufacturing, IT network technology equipment, construction machinery sales and information transfer systems, thus enabling people to see a brand new construction machinery industry. New construction machinery products in the efficiency and operational quality, environmental protection, performance and automation are many areas due to the past. and toward the further robotic and intelligent direction. 1、 operating principles of Innovation : groundbreaking new law with the high-frequency vibration With scientific and technological research in the development, engineering machinery operating theory is constantly innovating. Operating mechanical engineering principles, including the cutting of earth, broken ground on the screen geotextile material, mixed with heating, right mixture of paving, leveling and compaction, etc These operations Jimmy initially bionics and Newtonian mechanics-based, Modern science and the development of engineering machinery operating principle of laying the foundation for innovation. For example, mechanical vibration and pulse jet, the photoelectric effect and thermal physics, the application of mechanical engineering to save resources and improve the quality of construction improve production efficiency, reliability and driving comfort and a degree of automation to create conditions. Excavators, bulldozers, loaders, and other earthmoving machinery cutting groundbreaking project, we had no struggle milling, high-frequency vibration, Liquid gas jet method and porous ground breaking law. Groundbreaking use of the new operating principle of transformation to a bucket, can loosen the soil excavation for the high-intensity rock, Under normal circumstances can reduce the unit cost of earthwork and improve production efficiency, and the soil near the building when substitute bored-blasting method.Vibratory Roller is a mechanical vibration and have reached a “sluggish vibration to“ operational effectiveness of the most powerful note. High-3frequency vibration compaction technology is the application of modern dynamics in the mechanical engineering important research results, In vibratory roller simultaneously with the application of vibration isolation theory. 90s of the 20th century, there have been a level of vibration (vibration) and vertical vibration directional vibration compaction method, and an AM-vibration and different from the harmonic vibration of chaotic vibration vibratory compaction operating principle, and the formation of the corresponding series of vibratory roller. Impact Roller broke the existing traditional cylindrical roller structure, Use 3-5 edge with the pressure roller polygon dragged by a tractor, 2-3 times per second in order to impact on the ground. This has dramatic impact on the seismic wave propagation characteristics, the depth of compaction several times with the RCC and incremental, 5m in the depths of the degree of compaction of up 90%-92%. Impact Roller is static shock, vibration and rub it smashes the comprehensive role for large fill, Collapse dry sand and soil filling the compaction. Asphalt paver Weiping equipment is operating principles of mechanical engineering innovation typical example. Fung plate diesel, liquefied petroleum gas or electric heating and 60 Hz frequency of vibration, and using infrared, ultrasonic or laser leveling, is a multidisciplinary high-tech applications. This leveling the technology can be applied to the ground plane, as amlodipine or fine leveling the slope. Transfer frequency mechanical vibration is also commonly used for drilling, stone crushing and sieving and Shen pulling piling works. The stone drying can use diesel, fuel oil and coal combustion of various fuels on the asphalt from the barrel, heating and asphalt mixture, stirring and insulation process is the full use of thermal theory of physics. Asphalt emulsion and some are modified chemical reaction physical specific application. 2、drive innovation : universal hydraulic and electric drive Hydraulic drive in the 20th century, the 1960s applied to the roller, only 10 years on the time has been spread and popularize. Now roller travel, vibration, steering and braking systems has achieved the full hydraulic drive. 4Hydraulic drive greatly simplified the roller drive and control system design, hydraulic drive a smooth, convenient manipulation effort, easy to achieve variable speed and automation, in general, improve the production efficiency of roller compaction and quality. Now foreign markets have seen very little mechanical transmission of the roller.Hydrostatic drive technology in the 1970s began to use bulldozers, and will soon be extended to a number of small and medium bulldozers and loaders, the United States John Deere, Caterpillar, Germany Bohai benefit companies and Dole produced by Komatsu of Japan has production and sales pushed Temple hydraulic machines and loaders. Hydrostatic drive not to use hydraulic torque converter, which dispense with the left lane and brake parts and mechanical drive, use of a safety valve on mechanical and hydraulic systems overload protection, and the index of smaller power play biggest index, its remaining power available in the auxiliary machinery operation. German company Deutsche mark and Lee Bohai Fall of other public companies in 1954 and in 1955 took the lead in developing a hydraulic excavator , but the hydrostatic transmission in large excavator is the popularization and application of the 1970s. Since the early 1980s, excavators and subdivided, is gradually realized - powered, rotary and the hydraulic excavator of. In the international market excavators, were all eliminated various mechanical drive. Late history of the birth of the road is more mechanical hydraulic drive-based, such as paver, soil stabilizer, Pavement milling machine, hydraulic transmission smoothness help improve the quality of the roads paved. Drilling in the car and drilling machines, hydraulic transmission has replaced the previous aerodynamic, Wheeled modern cranes and machinery also piling work to the whole in the direction of hydraulic development. Electricity in industrial production while the application has a long history, but in mobile machinery is seldom used. This is because, firstly, to the motor capacity of, a motor with the same power as compared to the hydraulic motor, its weight and bulk to good times, to the machinery space 5layout brought great difficulties. In addition, the efficiency of electrical transmission over low efficiency and consumption of a large volume of non-ferrous metals. But electric drive can be well realized variable speed, braking and electrical power streaming - Drive more convenient and easy to large tub, large excavator and large loaders, engine-generator-electric wheels will transfer power. Germany Vogele also been developed for electric power will transfer wheel. Germany Vogele also been developed electric drive an asphalt paver, the aircrafts systems are all rotary motor driven electricity, Only Hopper CDCC and comfort slab leveling tank still use hydraulic transmission. The other is the regional mobile operations in the smaller mining site, the use of electric drive large excavator loaders, Such use of electric drive power transmission cables without the engine installed on the machines.3、ergonomic innovations : a people-oriented and simplified operation 1980s of the 20th century, Many of the worlds largest engineering machinery manufacturing company has invested considerable human and financial resources for modern design methodology of the research and used. Ergonomics is a “people-oriented“ design, with emphasis on the machines mutual coordination and crew safety, driving comfort, convenience in the drivers operation and maintenance technologies, such drivers both improved working conditions, and increased production efficiency, and some of the engineering machinery vibration, noise, emissions and the prevention of roller drop from the development of the new standard, and even those laws. Now all kinds of projects are mechanical design roller defense and falling-object protective devices to protect the personal safety of the drivers, with the cab and are designed and installed. Indoor driving sufficient human space and broad vision, and to take the necessary seals, vibration, noise and temperature control measures. Indoor chairs, pieces of the stick, gauges and the monitor according to ergonomics and design and minimize the manipulation and control of parts. To reduce driver fatigue, to choose the suspension damping chairs, and to develop a gas-liquid system hanging with the cab floor. 6Electronic technology, mechanical engineering applications, which greatly simplifies the drivers operational procedures and to the machines technical performance. The use of electronic control machine can automatically choose the mode of operation, such as excavators to the three operating modes - boom priority, Rotary priorities and micro-adjustment tandem wheels all vibration and vibration. Electronic monitoring can detect and remove machines system failures, such as engine oil pressure loss. Fan fracture belt drive, hydraulic oil contamination or overheating and oil filter blockage, can promptly lights or audible alarm, by the use of electronic sensor device can handle automatic detection machines quality of the work, If random vibration testing of the degree of compaction roller, automatic detection and adjustment of the asphalt mixture ratio and size distribution outlet temperature.American muffler technology company developed an electronic silencer, electronic equipment engine exhaust noise analysis of the wave structure, and produce a phase difference of 180 with the acoustic interference, This “anti-noise“ and the engine exhaust noise offset, which over the purpose of the muffler. Such a muffler - can be used to eliminate the basic engine noise and the noise indoor driving. Muffler and isolation through the engineering machinery driving indoor noise can be reduced to 70dB (A) below.In addition, by concentrating on lubrication, automatic lubrication and fault alarm, greatly reducing the engineering and mechanical maintenance workload. Dreiser companies axis articulated loader lubrication cycle extended to 2000h. oil and filter replacement cycle extended to 250h; Caterpillar loader routine maintenance to shorten the time 3.45min. 100 hours use of the technical maintenance for only 6-7min. 4、Creative : industrial design with the environment Modern science and technology of high-speed development, promoting social progress, for humanity to a high degree of material civilization and spiritual civilization. Industrial design is the product of industrial product design, product also known as the art form. Mechanical Products art forms 7should be able to demonstrate its function in a rational and external quality of uniformity, the product should reflect the advanced technology and meet the aesthetic requirements of modernity. For mechanical engineering, said it was “a Paper goods sold,“ That is an exaggeration, but not to modeling design is certainly not desirable. Modeling the mechanical engineering design of the machine can shape their structure, function and use requirements, paying and with the psychological and physical coordination. This modeling design should include ministries of proper body fluid, color coordination, Instrumentation layout beautiful and easy to operate and intuitive sign in the trademark symbol. Now the worlds major companies have attached great importance to the products of industrial design, and a specialized research and design. A world leader left the compactor manufacturers - BMW, his third of the mechanical compaction machine modeling experts from the industrial design Louis.L.lepoix design, have a good overall result. The series dismounting replacement filter, transmission pieces, hoses and routine maintenance is very convenient. Adopt modern arc-shaped dip in the cab and the engine hood broadminded, fluent lines, with the flavor of the times. Driving the steering wheel height and angle adjustable, choose a comfortable high back seats adjustable damping. Drivers prepare for a good operating environment. Instrumentation site design, easier to observe and control, tilt hood of the driver to provide a good perspective. Hydraulic steering gear shifted to the cab, driving to reduce indoor heat and noise. Arc-shaped windscreen of the cab and four SUPPORT able to isolate noise and vibration. indoor noise below 70dB (A).Many other engineering machinery are also different degrees of emphasis on industrial design, layout components such as depression, to reduce the center of gravity of the aircraft; Supporting appropriate to expand the area to increase the machines stability; about as symmetrical layout, to meet the aesthetic; Appearance removed some of the corner, the edge, to show the fluency, and other lines. Construction Machinery paint more of its 8industrial design is an important part of the unit should be interesting colors, increase the safety of the working environment, and with the field construction site is pure green fields, coordination, Topping the use of the waist line and increase the level to get off the color machines can increase the concentration of visual stability.、artificial intelligence Innovation : intelligent robotic machines Mechanical engineering in the construction field instead of the manual to expand the functions of the hands and feet, traditional machinery can be resolved in good physical and physiological burden, not to mention the relief of spiritual and psychological burden. Modern engineering machinery should be given its soulful, intelligent engineering machinery is a thinking mind (microcomputer) sensorium (sensors), neural network (electronic transmission). Derrnatopathy (power and transmission), and hand, foot bones (work with devices running) for telecommunications systems integration. Machine is not electromechanical integration of telecommunications and information technology with a simple, it poses the system must have five functions : detection and identification with the objects of their work and working conditions of the function; goal with under their own decision-making function; have to respond to the decision-making, implementation support movement functions; with automated monitoring and self-revision process functions; z own self-protection and security troubleshooting functions. This is the Intelligent Engineering Machinery some specific goals. In mechanical engineering intelligent process, from beginning to end, filled with self-learning technology and the use of adaptive technology. Now for the integration of telecommunications technology for the engine and hydraulic system and electrical system of full control machines are being given various feelings and wisdom. In the process with the state of real-time monitoring on the basis of mechanical engineering from the partial automation of the transition to full automation, and toward unmanned remote control and the trend of development. With the intervention of artificial intelligence, engineering machinery will accelerate its modern fast process, 9Gradual transition to a fully operational wisdom of the target robot. At that time, some new robotic operating procedures will come into being.10现代工程机械行业的技术进步大型机械式挖掘机在目前国际国内在矿山开采及工程施工中有着广泛的应用，其性能的优劣对生产率有很大的影响.在国际市场竟争日趋激烈的今天，如何提高产品的质量是提高其市场竞争力的关键。目前，我国的大型机械式挖掘机在设计水平，设计手段及产品质量上与国外同类产品相比尚有较大差距.国外已经将人一机一环境作为一个系统统一考虑，提倡低振动、低噪音的绿色设计，将现代设计方法(电子模拟理论、动态设计、可靠性设计等)普遍地应用于挖掘机设计，使产品设计现代化，性能可靠。而我国仍然主要采用传统的仿型

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