汽车起重机毕业设计外文翻译
机械毕业设计英文外文翻译58拆装小车概述
附录附录A英文科技文献Disassembly Automotive OverviewCar shortly after the invention of the automobile repair and then had the industry. In order to convenient maintenance，with jack lifting machine maintenance tools to appear. The early simple columnar foundation type hydraulic lifting machine，is greatly raised than it was still early jack and the function of the test bench，this early lifting machine can rotate function in lifting the car later，rotating 360 °. Maybe you often go to a car maintenance，now still use the lift machine to provide daily vehicle maintenance service，this kind of lifting machine has largely work for 75 years.Along with the development of the car industry，simple columnar type elevator machine design，the limitation of shows up soon. If only in car around for testing maintenance work of words，the lifting machine will be enough，but this lifting machine and the central pillar of the hoist boom would hamper into the bottom of the car most area. For simple columnar type elevator machine of these limitations，engineers have put forward a lot of lifting machine design scheme and a lot of improvement work. Now，lifting machine selection scope of great，have foundation type，spots，cut the type，type of parallel four edges form，portable，simple columnar type，double column type，four-column type，driving type，contact the car battery，symmetric，the symmetric，small trip，big lift，queue，and other various type of lifting machine design. Some lifting machine may also.In the market can see different types of different size，lifting machine，there are some particularly suitable for engaged in special type of maintenance work，there are a few lifting machine for some other maintenance work.Double column spots car battery lifting machine is contact a widespread adoption of lifting machine，in recent years all new sales lifting machine，at least two-thirds are this type. This design is very popular，there are several reasons: one is the lifting machine installation quick，do not need a wide range of excavation，also do not need to enterprise's whole layout some permanent changes. 2 it is the diversity of function，a double column spots car battery lifting machine with almost all can be used for the car maintenance work. The lifting of the machine and contact the layout of cantilever pad，making maintenance technician can easily into the bottom of the car，the car in operation and maintenance. Therefore，almost all major liftingmachine manufacturers to at least one type of production double column spots type elevator machine.In recent years，I had a booming industry，especially the car industry，DuoNian to cars into the ordinary families dream has become a reality. Vehicle repair industry has got to develop，all kinds of maintenance equipment needs rapid expansion. Auto lift machine is necessary maintenance，is also the most important maintenance machinery.Auto lift machine is the role of the need of repair car level to the appropriate height，so that maintenance workers in car chassis of automobile maintenance. Below Auto lift machine such as mentioned above，the main divided into pillar type and shear type two kinds，no matter which kind of，the demand from both sides to car level synchronization up，and can't happen migration. And car chassis below must be empty. To facilitate the maintenance workers homework. This requires auto lift machine lifting device must be on both sides of the separation of both sides，and rise or fall must be synchronous. Because of the weight of the car generally very big，and lift for special smoothly，so auto lift machine typically use the hydraulic drive system. Besides the requirement from a certain range from cars both sides synchronous lifting the decline and car，also requires its can make cars at any height to stop and to keep still，so that different height of the workers in maintenance，at different location can adjust height，the most convenient for repair，so hydraulic system must have positioning keep function. In addition for car weight is very big，once hydraulic system failure，lifting machine for arm in car the force of gravity will decline rapidly to pull off the maintenance workers may be the life security threats，lifting the car on and broke the danger. So in order to prevent this happens，lifting machine must have mechanical locking devices，mechanical locks were installed in by lifting cylinder piston rod and the top and lifting arm connected pin shaft on the two root jagged rack，installation of the oil cylinder to the outside of the rack is stationary. And can the pin shaft do certain Angle，to the swing of the separation of the two root rack and mesh. When lifting arm in positioning state or hydraulic system failure，hydraulic below a certain value，dynamic rack will of its own gravity and spring under the action of forces and still rack meshing，mechanical locked，increased the lifting the security of the machine.Nearly 20 years the world lifting machine industry has changed greatly. RT (off-road tires lifting machine) and AT the whole earth to lifting machine () of the rapid development of products，broke original product and market structure，economic development and market in the fierce competition in the world，the impact of lifting machine market further integration trend. At present the lifting machine years sales has the world around us $7.5 billion. The mainproducers for the United States，Japan，Germany，France，Italy，etc，the world's top companies have more than 10 factories，mainly concentrated in the North America，Japan (Asia) and Europe.The United States is lifting machine main producer countries，it is one of the largest in the world market. But because Japan，Germany lifting machine rapid development of industry and RT and AT the rise of American manufacturers，products have in the s to 70 s，the world leading position in the field of possession is gradually weakened，so as to form the United States，Japan and Germany tripartite balance of power. In recent years the United States economy picks up，market，foreign manufacturers are active to participate in the competition. The strength of the American manufacturers also improved，TeLeiKeSi elevator company that is the rise of examples. TeLeiKeSi elevator company predecessor is the colin lifting depots. Since 1995，through a series of the merger activity，has become one of the world's top companies.Japan from the 1970 s become lifting machine production country，product quality and quantity improve soon，have been exported to European and American markets，annual production ranked first in the world. Since 1992，due to the yen's appreciation，domestic infrastructure investment dropped and the Asian financial crisis，the annual output to drop. At present，the market demand for years for 3000 units or so.Europe is a large market potential，European industrial nations lifting machine is the exporter，but also the important importer. Germany is the largest European market，followed by Britain，France，Italy and other countries. In Germany AT products market share，liebherr accounted for 53%，16%，DE lafugelufu horse) 14%，many fields and TeLeiKeSi each account for 10% and 5%.Lifting machine manufacture the wind of the combined with the auto industry is very similar，in the car industry，general motors，ford，BMW，Mercedes，Renault，public companies are on the way to unite，the two industries has been one of the world market. In the world to mature market for market share and maintain growth，shortcut is to buy rival，the long-term goal is to win the world market dominance. In the elevator industry，in a sense，into the world market means that into North America，Japan (Asia) and Europe market.附录B 文献翻译拆装小车概述汽车发明后不久便有了汽车维修的行业。
毕业论文外文资料翻译-现代起重机的特征和发展趋向
Characteristics and DevelopmentalTendency of Modern CranesWith rapid development of modern science and technology, magnification of industrial production scale and improvement of automation level, application of cranes is becoming widespread and its function is obvious. Meanwhile, requirements for cranes are more and more strict. Especially, the widespread use of electronic computer technology spurs lots of subject-crossing advanced design approaches and accelerates the improvement of modern manufacturing and detecting technology. Fierce competition in international market becomes more dependent on the competition of technology. All of these impel technological functions of cranes into a brand-new developmental stage. Cranes are facing a tremendous transformation.Our country is entering global international competitive market at an unprecedented rate and crane manufacture is confronted with a new situation where opportunities and challenges coexist. Thus, it is crucial for cranes to develop and innovate constantly. I want to make a brief explanation about characteristics and developmental tendency of modern cranes with examples, based on new theories, technology and trend of cranes at home and overseas.1.Make the key products large, high speed, endured and specializedBecause of continuous expansion of industrial production scale, increasingly improvement of production efficiency and rising proportion of money spending on loading and unloading and transporting materials in the process of production, required amount of large or high-speed cranes is increasing. Lifting quantities become larger, working speed becomes higher and requirements of energy-consuming and reliability become stricter. Cranes have already become a critical link in the process of automation production. Cranes should be easy to use, maintain and operate and have high security, less troubles and long average time between failures. The central issue in international market production competition is reliability, and many companies abroad have drawn up inter-controlled standard of reliability. The most important for us to catch up with and surpass world advanced level of crane’s function is to improve reliability, to make cranes durable, less troubles, maintainable and economic to be used.At the moment, the biggest floating crane in the world weighs 6500t, chain crane 3000t and bridge crane 1200t.Diversity of industrial mode of production and customers’need makes crane market expanding and products renewing constantly to satisfy special needs with specific functions and bring its best usefulness into play. Functions of various kinds of cranes are improving. DEMAG ERGOTECH has developed a crane special for aircraft maintenance, which has made its own way into international market. This crane is great in length and lifting height and has accurate halt. When a flexible maintenance platform fixed under lifting cart, it can reach every part of the aircraft. With the fast development of nuclear power stations in the world, cranes which are special for them achieve corresponding development. For example, annular bridge crane in reactors’space, working under radiative circumstances, is used to lift dangerous load such as top cover of pressure container and components in reactors. It requires high reliability, high security, the ability to determine location accurately and automatically and transfer goods to a lower level, as well as various kinds of protection and particular security devices.2. Make series of production modularized, combined, standardized and practicalMost cranes are produced by series and batch, thus use of systematic multi-objections entire optimization to design series of cranes has already become the key point in development. Through rational matching of series main parameter, its functions can be improved, manufacturing cost can be reduced, and degree of general purpose can be raised. Use less specification spare parts to compose series production with multi-species and multi-specifications. And thus, the requirements of customers can be fully satisfied.By using modularized design instead of conservative entire design, we can make components with similar functions into standard modules which have various uses, similar connective key factors and are interchangeable. Through combination of different modules, we can make different kinds and specifications of cranes. There are only several modules involved when it comes to crane improvement. To design a new style of crane, all that you do is to choose different modules to recompose. Because of improvement in degree of general purpose, single products with small serial production can transform into module production of pretty great batches. As a result, we can achieve specialization production with high efficiency and cut manufacturing cost. It can satisfy marketing demands and increase competitive capacity by composing cranes of various series and specifications using less modularized forms.Bridge crane produced by DEMAG ERGOTECH considered carefully modularization and combination. It makes inter-parameter of series, entirety, mechanism and components matched with each other. The distribution of capacity obtains most economic and suitable effects. To make the main components of lifting mechanism reaches its largest general purpose, the method that the result of lifting weights multiplying lifting speed is a constant has been used. There are more specifications derived through changes of pulley multiplying power. Series of 5-125t bridge cranes only need four basic lifting carts even with various working ranks. Module series of standard wheel cases, which are produced by the company, have various groups of linking holes which can choose different drive unit to form platform carts. They can also combine with metal construction components to be used as running machine of various kinds of cranes; its wheels have several forms of surfaces to be chosen. Because of no basic distance limit and flexible combination, they are widely used. The company’s series of end bridge standard modules have commercialized. It resorts to frictional cycle and high intensity bolt link which improves interchange and accuracy of sizes and reduces machining of connecting covers. It can connect to each main beam quickly and effectively. There are two kinds of end beam modules; one is suitable for single beam and the other is for double beams. According to length and weights, end beam style can be decided.3. Make productions for general purposes small, light, simple and diversifiedThere are quite a number of cranes used in general workshop and storehouse, and thus they have light work and the requirement is not very strict. How to improve application of these cranes and to cut manufacturing cost is critical to win in the marketing competition. Considering comprehensive benefit, the need to decrease the height of cranes as low as possible, to simplify the constructions and to reduce weights and wheel pressure can also decrease structure’s height, lighten structure composition and reduce cost of producing and maintenance. So there will be fast development of electric calabash bridge and light beam cranes, and bridge cranes for general purposes will be replaced by them.The needs of customers advance diversity of cranes. Series parameter scale of cranes expanding and functions enlarging, product of one machine for several useswill obtain further development to increase capacity of dealing with emergencies. The proportion of using wireless remote control under normal conditions will increase.DEMAG ERGOTECH has formed standard crane series of light combinations after long period explosion and innovation. The whole series compose of various productions such as combination “工” style single beam, hanging case single beam, horn cart case single beam and case double beams. There are altogether fifteen forms of connection between main beam and end beam. This is suitable for needs of different structure and lifting goods. Each specification of crane has three single speeds and three double speeds to be chosen. There are seven operating ways. In addition, different electric conduction pattern and different electric control pattern can match hundreds and thousands of cranes through different combinations to fully satisfy different needs of customers. Another advantage of the crane is that they are light. Compared to productions at home, its lifting weight is 32t and length 25.5m compared to 46.4t------weight of double beams cranes in our country, 28.3t------ electric calabash bridge cranes. Weight of DEMAG electric calabash bridge crane is only 18.5, which is lighter than domestic productions by 60 percent and 35percent respectively.现代起重机的特征和发展趋向随着现代科学技术的迅速发展，工业生产规模的扩大和自动化程度的提高，起重机在现代化生产过程中应用越来越广，作用愈来愈大，对起重机的要求也越来越高。
毕业设计---行走式小型液压起重机设计(含外文翻译)
题目：行走式小型液压起重机设计姓名：班级学号：指导教师：摘要随着国民经济的迅速发展，国内汽车起重机的市场需求也在不断增加。
各起重机生产厂为了争夺更多的市场份额，都在不断对自己的产品进行更新换代。
谁先开发出技术含量高、适销对路的新产品，谁就能先赢得更多的市场。
面对竞争日益激烈的起重机市场，开发新一代汽车起重机成为各起重机生产厂的当务之急行走式小型液压起重机主要有行走系统，电气控制系统和液压控制系统三部分组成。
将小车底盘作为工作台，电动机，液压系统和吊臂都安装在上面，由遥控装置来控制电动机，通过电动机对液压泵的控制，从而控制液压马达的转速和液压缸的活塞速度，以实现规定的动作。
行走式小型液压以齿轮泵作为动力源，采用液压先导比例控制，符合国情，既便于生产和采购，又降低了制造成本，有利于大批量组织生产。
关键词遥控装置；齿轮泵；液压先导比例控制。
AbstractWith the rapid development of the national economy, the domestic automobile market demand crane has also increased. To the crane manufacturing plant for more market share, in the constant upgrading of their products. Whoever developed high technological content, marketable new products, which will be able to win more market? Faced with the crane in an increasingly competitive market, to develop a new generation of the crane truck crane to become the top priority production plantWalk-mainly small hydraulic crane operating system, electrical control system and hydraulic control system consists of three parts. As a car chassis will be working platforms, electrical, hydraulic systems and are installed on the crane above, by a remote control device to control the motor, the hydraulic pump through the motor control and thus control the speed of hydraulic motors and hydraulic cylinder piston speed To achieve the required action.Small walk-in hydraulic gear pump as a power source, the pilot of a hydraulic control, in line with national conditions, both for production and procurement, and lower manufacturing costs and is conducive to high-volume production.Key words a remote control device；gear pumps；hydraulic control of the pilot.毕业论文（设计）用纸目录摘要IAbstract II第 1 章绪论 (2)1.1现代制造系统物流技术 (2)1.2现代物流的发展方向 (3)1.3现代生产物流的特点 (4)1.3.1 现代化的物流设备 (4)1.3.2 计算机管理 (4)1.3.3 系统和集成化 (5)第 2 章动力及传动的设计与计算 (6)2.1系统工作原理及方案的确定 (6)2.2有轨小车运行机构计算 (6)2.2.1 确定机构运行方案 (6)2.2.2 车轮与轨道并验算其强度 (6)2.2.3 选电动机验算电动机发热条件 (9)2.2.4 选择减速器验算运行速度和实际所需功率 (10)2.2.5 选择制动器 (13)2.2.6 浮动轴设计 (14)2.3回转运行机构的计算 (15)2.3.1 确定回转机构的总体方案 (15)2.3.2 轨道直径和中心枢轴计算 (15)2.3.3 选定工业车轮 (17)2.4齿轮传动设计 (17)2.4.1 选定齿轮类型、精度等级及齿数 (17)2.4.2 按接触强度设计 (17)2.4.3 按齿根弯曲强度设计 (19)2.4.4 几何尺寸计算 (20)参考文献 (22)致谢23附录1 24附录2 31第 1 章绪论1.1 现代制造系统物流技术物流系统技术是先进制造技术中的重要组成部分，从其广义内涵分析可以看出它已从以前简单的物料搬运发展到今天的集机械设计、计算机科学、管理学和自动化控制技术等于一身的综合技术。
起重机中英文对照外文翻译文献
起重机中英⽂对照外⽂翻译⽂献中英⽂对照外⽂翻译(⽂档含英⽂原⽂和中⽂翻译)Control of Tower Cranes WithDouble-Pendulum Payload DynamicsAbstract：The usefulness of cranes is limited because the payload is supported by an overhead suspension cable that allows oscilation to occur during crane motion. Under certain conditions, the payload dynamics may introduce an additional oscillatory mode that creates a double pendulum. This paper presents an analysis of this effect on tower cranes. This paper also reviews a command generation technique to suppress the oscillatory dynamics with robustness to frequency changes. Experimental results are presented to verify that the proposed method can improve the ability of crane operators to drive a double-pendulum tower crane. The performance improvements occurred during both local and teleoperated control.Key words：Crane , input shaping , tower crane oscillation , vibrationI. INTRODUCTIONThe study of crane dynamics and advanced control methods has received significant attention. Cranes can roughly be divided into three categories based upontheir primary dynamic properties and the coordinate system that most naturally describes the location of the suspension cable connection point. The first category, bridge cranes, operate in Cartesian space, as shown in Fig. 1(a). The trolley moves along a bridge, whose motion is perpendicular to that of the trolley. Bridge cranes that can travel on a mobile base are often called gantry cranes. Bridge cranes are common in factories, warehouses, and shipyards.The second major category of cranes is boom cranes, such as the one sketched in Fig. 1(b). Boom cranes are best described in spherical coordinates, where a boom rotates aboutaxes both perpendicular and parallel to the ground. In Fig. 1(b), ψis the rotation aboutthe vertical, Z-axis, and θis the rotation about the horizontal, Y -axis. The payload is supported from a suspension cable at the end of the boom. Boom cranes are often placed on a mobile base that allows them to change their workspace.The third major category of cranes is tower cranes, like the one sketched in Fig. 1(c). These are most naturally described by cylindrical coordinates. A horizontal jib arm rotates around a vertical tower. The payload is supported by a cable from the trolley, which moves radially along the jib arm. Tower cranes are commonly used in the construction of multistory buildings and have the advantage of having a small footprint-to-workspace ratio. Primary disadvantages of tower and boom cranes, from a control design viewpoint, are the nonlinear dynamics due to the rotational nature of the cranes, in addition to the less intuitive natural coordinate systems.A common characteristic among all cranes is that the pay- load is supported via an overhead suspension cable. While this provides the hoisting functionality of the crane, it also presents several challenges, the primary of which is payload oscillation. Motion of the crane will often lead to large payload oscillations. These payload oscillations have many detrimental effects including degrading payload positioning accuracy, increasing task completion time, and decreasing safety. A large research effort has been directed at reducing oscillations. An overview of these efforts in crane control, concentrating mainly on feedback methods, is provided in [1]. Some researchers have proposed smooth commands to reduce excitation of system flexible modes [2]–[5]. Crane control methods based on command shaping are reviewed in [6]. Many researchers have focused on feedback methods, which necessitate the addition necessitate the addition of sensors to the crane and can prove difficult to use in conjunction with human operators. For example, some quayside cranes have been equipped with sophisticated feedback control systems to dampen payload sway. However, the motions induced by the computer control annoyed some of the human operators. As a result, the human operators disabled the feedback controllers. Given that the vast majority of cranes are driven by human operators and will never be equipped with computer-based feedback, feedback methods are not considered in this paper.Input shaping [7], [8] is one control method that dramatically reduces payload oscillation by intelligently shaping the commands generated by human operators [9], [10]. Using rough estimates of system natural frequencies and damping ratios, a series of impulses, called the input shaper, is designed. The convolution of the input shaper and the original command is then used to drive the system. This process is demonstrated with atwo-impulse input shaper and a step command in Fig. 2. Note that the rise time of the command is increased by the duration of the input shaper. This small increase in the rise time isnormally on the order of 0.5–1 periods of the dominant vibration mode.Fig. 1. Sketches of (a) bridge crane, (b) boom crane, (c) and tower crane.Fig. 2. Input-shaping process.Input shaping has been successfully implemented on many vibratory systems including bridge [11]–[13], tower [14]–[16], and boom [17], [18] cranes, coordinate measurement machines[19]–[21], robotic arms [8], [22], [23], demining robots [24], and micro-milling machines [25].Most input-shaping techniques are based upon linear system theory. However, some research efforts have examined the extension of input shaping to nonlinear systems [26], [14]. Input shapers that are effective despite system nonlinearities have been developed. These include input shapers for nonlinear actuator dynamics, friction, and dynamic nonlinearities [14], [27]–[31]. One method of dealing with nonlinearities is the use of adaptive or learning input shapers [32]–[34].Despite these efforts, the simplest and most common way to address system nonlinearities is to utilize a robust input shaper [35]. An input shaper that is more robust to changes in system parameters will generally be more robust to system nonlinearities that manifest themselves as changes in the linearized frequencies. In addition to designing robust shapers, input shapers can also be designed to suppress multiple modes of vibration [36]–[38].In Section II, the mobile tower crane used during experimental tests for this paper is presented. In Section III, planar and 3-D models of a tower crane are examined to highlight important dynamic effects. Section IV presents a method to design multimode input shapers with specified levels of robustness. InSection V, these methods are implemented on a tower crane with double-pendulum payload dynamics. Finally, in Section VI, the effect of the robust shapers on human operator performance is presented for both local and teleoperated control.II. MOBILE TOWER CRANEThe mobile tower crane, shown in Fig. 3, has teleoperation capabilities that allow it to be operated in real-time from anywhere in the world via the Internet [15]. The tower portion of the crane, shown in Fig. 3(a), is approximately 2 m tall with a 1 m jib arm. It is actuated by Siemens synchronous, AC servomotors. The jib is capable of 340°rotation about the tower. The trolley moves radially along the jib via a lead screw, and a hoisting motor controls the suspension cable length. Motor encoders are used for PD feedback control of trolley motion in the slewing and radial directions. A Siemens digital camera is mounted to the trolley and records the swing deflection of the hook at a sampling rate of 50 Hz [15].The measurement resolution of the camera depends on the suspension cable length. For the cable lengths used in this research, the resolution is approximately 0.08°. This is equivalent to a 1.4 mm hook displacement at a cable length of 1 m. In this work, the camera is not used for feedback control of the payload oscillation. The experimental results presented in this paper utilize encoder data to describe jib and trolley position and camera data to measure the deflection angles of the hook. Base mobility is provided by DC motors with omnidirectional wheels attached to each support leg, as shown in Fig. 3(b). The base is under PD control using two HiBot SH2-based microcontrollers, with feedback from motor-shaft-mounted encoders. The mobile base was kept stationary during all experiments presented in this paper. Therefore, the mobile tower crane operated as a standard tower crane.Table I summarizes the performance characteristics of the tower crane. It should be noted that most of these limits areenforced via software and are not the physical limitations of the system. These limitations are enforced to more closely match theoperational parameters of full-sized tower cranes.Fig. 3. Mobile, portable tower crane, (a) mobile tower crane, (b) mobile crane base.TABLE I MOBILE TOWER CRANE PERFORMANCE LIMITSFig. 4 Sketch of tower crane with a double-pendulum dynamics.III. TOWER CRANE MODELFig.4 shows a sketch of a tower crane with a double-pendulum payload configuration. The jib rotates by an angle around the vertical axis Z parallelto the tower column. The trolley moves radially along the jib; its position along the jib is described by r . The suspension cable length from the trolley to the hook is represented by an inflexible, massless cable of variable length 1l . The payload is connected to the hook via an inflexible, massless cable of length 2l . Both the hook and the payload are represented as point masses having masses h m and p m , respectively.The angles describing the position of the hook are shown in Fig. 5(a). The angle φrepresents a deflection in the radial direction, along the jib. The angle χ represents a tangential deflection, perpendicular to the jib. In Fig. 5(a), φ is in the plane of the page, and χ lies in a plane out of the page. The angles describing the payload position are shown in Fig. 5(b). Notice that these angles are defined relative to a line from the trolley to the hook. If there is no deflection of the hook, then the angleγ describes radial deflections, along the jib, and the angle α represents deflections perpendicular to the jib, in the tangential direction. The equations of motion for this model were derived using a commercial dynamics package, but they are too complex to show in their entirety here, as they are each over a page in length.To give some insight into the double-pendulum model, the position of the hook and payload within the Newtonian frame XYZ are written as —h q and —p q , respectivelyWhere -I , -J and -K are unit vectors in the X , Y , and Z directions. The Lagrangian may then be written asFig. 5. (a) Angles describing hook motion. (b) Angles describing payload motion.Fig. 6. Experimental and simulated responses of radial motion.(a) Hook responses (φ) for m 48.01=l ，(b) Hook responses for m 28.11=lThe motion of the trolley can be represented in terms of the system inputs. The position of the trolley —tr q in the Newtonian frame is described byThis position, or its derivatives, can be used as the input to any number of models of a spherical double-pendulum. More detailed discussion of the dynamics of spherical double pendulums can be found in [39]–[42].The addition of the second mass and resulting double-pendulum dramatically increases the complexity of the equations of motion beyond the more commonly used single-pendulum tower model [1], [16], [43]–[46]. This fact can been seen in the Lagrangian. In (3), the terms in the square brackets represent those that remain for the single-pendulum model; no —p q terms appear. This significantly reduces the complexity of the equations because —p q is a function of the inputs and all four angles shown in Fig. 5.It should be reiterated that such a complex dynamic model is not used to design the input-shaping controllers presented in later sections. The model was developed as a vehicle to evaluate the proposed control method over a variety of operating conditions and demonstrate its effectiveness. The controller is designed using a much simpler, planar model.A. Experimental V erification of the ModelThe full, nonlinear equations of motion were experimentally verified using several test cases. Fig.6 shows two cases involving only radial motion. The trolley was driven at maximum velocity for a distance of 0.30 m, with 2l =0.45m .The payload mass p m for both cases was 0.15 kg and the hook mass h m was approximately 0.105 kg. The two cases shown in Fig. 6 present extremes of suspension cable lengths 1l . In Fig. 6(a), 1l is 0.48 m , close to the minimum length that can be measured by the overhead camera. At this length, the double-pendulum effect is immediately noticeable. One can see that the experimental and simulated responses closely match. In Fig. 6(b), 1l is 1.28 m, the maximum length possible while keeping the payload from hitting the ground. At this length, the second mode of oscillation has much less effect on the response. The model closely matches the experimental response for this case as well. The responses for a linearized, planar model, which will be developed in Section III-B, are also shown in Fig. 6. The responses from this planar model closely match both the experimental results and the responses of the full, nonlinear model for both suspension cable lengths.Fig. 7. Hook responses to 20°jib rotation:(a) φ (radial) response;(b) χ (tangential) response.Fig. 8. Hook responses to 90°jib rotation:φ(radial) response;(b) χ(tangential) response.(a)If the trolley position is held constant and the jib is rotated, then the rotational and centripetal accelerations cause oscillation in both the radial and tangential directions. This can be seen in the simulation responses from the full nonlinear model in Figs. 7 and 8. In Fig. 7, the trolley is held at a fixed position of r = 0.75 m, while the jib is rotated 20°. This relatively small rotation only slightly excites oscillation in the radial direction, as shown in Fig. 7(a). The vibratory dynamics are dominated byoscillations in the tangential direction, χ, as shown in Fig. 7(b). If, however, a large angular displacement of the jib occurs, then significant oscillation will occur in both the radial and tangential directions, as shown in Fig. 8. In this case, the trolley was fixed at r = 0.75 m and the jib was rotated 90°. Figs. 7 and 8 show that the experimental responses closely match those predicted by the model for these rotational motions. Part of the deviation in Fig. 8(b) can be attributed to the unevenness of the floor on which the crane sits. After the 90°jib rotation the hook and payload oscillate about a slightly different equilibrium point, as measured by the overhead camera.Fig.9.Planardouble-pendulummodel.B.Dynamic AnalysisIf the motion of the tower crane is limited to trolley motion, like the responses shown in Fig. 6, then the model may be simplified to that shown in Fig. 9. This model simplifies the analysis of the system dynamics and provides simple estimates of the two natural frequencies of the double pendulum. These estimates will be used to develop input shapers for the double-pendulum tower crane.The crane is moved by applying a force )(t u to the trolley. A cable of length 1l hangs below the trolley and supports a hook, of mass h m , to which the payload is attached using rigging cables. The rigging and payload are modeled as a second cable, of length 2l and point mass p m . Assuming that the cable and rigging lengths do not change during the motion, the linearized equations of motion, assuming zero initial conditions, arewhere φ and γ describe the angles of the two pendulums, R is the ratio of the payload mass to the hook mass, and g is the acceleration due to gravity.The linearized frequencies of the double-pendulum dynamics modeled in (5) are [47]Where Note that the frequencies depend on the two cable lengths and the mass ratio.Fig. 10. Variation of first and second mode frequencies when m l l 8.121=+.。
汽车起重机设计(毕业论文)
摘要随着经济建设的迅速发展，我国的基础建设力度正逐渐加大，道路交通，机场，港口，水利水电，市政建设等基础设施的建设规模也越来越大，市场汽车起重机的需求也随之增加。
本文通过对徐工50吨汽车起重机主臂进行研究，进一步进行主臂设计，通过计算对主臂的三铰点、主臂的长度、及每节臂的长度、液压缸尺寸进行确定，选择零部件，确定主臂伸缩方式及主臂内钢丝绳的缠绕方法，通过SOLID WORKS软件对主臂进行三维建模。
关键词：50吨汽车起重机、主臂设计、三铰点、伸缩方式、三维建模AbstractWith the rapid development of economic construction, China's infrastructure is gradually increase the intensity, road traffic, airports, ports, water conservancy and hydropower, municipal construction of infrastructure such as the scale of construction is also growing, crane truck crane market demand with the increase. Based on the Xu Gong 50 tons of truck crane boom study, further boom design, by calculating the main arm of the three hinges, the main arm length, and the length of each arm, hydraulic cylinder size identify, select Parts and components, identify the main telescopic arm and the boom in the way of winding rope method, SOLID WORKS software on the main arm for three-dimensional modeling.Keywords: 50-ton truck crane，the boom design，the three hinge points ，stretching，three-dimensional modeling目录摘要 (I)ABSTRATE (II)1绪论 (1)起重机械的工作特点及其在国民经济中的作用 (1)国内汽车起重机的发展概况和发展趋势 (2)国内汽车起重机的发展概况 (2)国内汽车起重机发展趋势 (3)国外汽车起重机发展概况及发展趋势 (4)国外汽车起重机发展概况 (4)国外汽车起重机发展趋势 (5)SOLID WORKS软件的介绍 (6)本课题内容及重要意义 (7)250吨汽车式起重机的主要技术参数和工作级别 (8)50吨汽车式起重机的主要技术参数 (8)50吨汽车起重机的工作级别 (10)350吨汽车起重机主臂尺寸确实定 (13)吊臂跟部铰点位置确实定 (13)吊臂各节尺寸确实定 (14)变幅液压缸铰点确实定 (15)吊臂截面的选择及截面尺寸确定 (17)4主臂伸缩机构的设计计算 (19)臂架伸缩机构的驱动形式 (19)臂架伸缩液压缸的计算及选择 (20)缸筒内径计算 (20)活塞杆直径 (21)缸筒壁厚及外径计算 (23)5零部件的选择 (24)钢丝绳的计算和选择 (24)钢丝绳结构形式的选用 (24)起升用钢丝绳直径的计算 (24)主臂伸缩用钢丝绳的计算选用 (25)滑轮及滑轮组的选择 (25)构造和材料的选用 (25)起升用滑轮尺寸确实定及选用 (26)滑轮组的选择 (27)6主臂的三维建模及装配 (28)基本臂的建模 (29)基本臂臂箍的建模 (29)理绳器的建模 (32)变幅缸支撑座建模 (34)基本臂的总装配 (36)主臂建模总装配 (37)结论 (42)致谢 (43)参考文献 (44)附录A (45)附录B (57)1绪论1.1 起重机械的工作特点及其在国民经济中的作用起重机械式用来对物料进行起重、运输、装卸和安装作业的机械。
机械毕业设计英文外文翻译304栏板起重装置的结构与设计 (2)
附录Steeplechase lifting device structure and design Lifting Gear steeplechase and design of the structure of the lifting mechanism is relatively traditional, the tail plate lifting mechanism using only a single fuel tank, so that the hydraulic system of the pipe is simple, convenient control and high reliability of the hydraulic system, and and ease of installation. The above analysis and calculation of the institutions such as the structure and properties of the mathematical relationship between parameters. To promote inter-related with the sleeve of the friction and wear, the sleeve guide groove angle and flip angle and a high degree of adaptability, such as lifting will be subject to further research and the analysis of the structure of hair.Lifting Gear steeplechase vehicle movements in foreign countries as the rear door (end plate), its installed in the car named after the tail. In this paper, according to national standards call a lifting gear steeplechase. Steeplechase a lifting device installed on the van in the carriage of goods, not only to demonstrate its proprietary water-resistant dust-proof function, but also in the loading and unloading of goods mechanization achieved.1. steeplechase development Lifting GearLifting Gear steeplechase development, largely in foreign countries can be divided into four periods. The first generation of products in the 30's at the end of this century, characterized mainly lifting cylinder, and the steeplechase manually turned on, from or about the quality of 500kg, steeplechase (also known as loading platforms) touchdown angle 9 ° ~ 10 °. At present, this product in South-East Asia, Japan still in use, 90 years, is still the United States by the new development. Second-generation products in the early 50's the European market, in the first generation of products based on the increase of turnover to close the fuel tank. Lift and flip the fuel tank by two to achieve independence. The most common is a type 4 tank, but also of the double. Lifting the quality of more than 500 kg, platform loading touchdown angle 10 °, flip action control based on the experience of the operator. The products are mainly used in the Americas and Southeast Asia. Third-generation products in the 70's at the end of the European market is the second generation of products based on the increase in the fuel tank of the fifth. Only the fuel tank of the hydraulic system in the relative positions of the main effect of memory function, so that touchdown to loading platform, off the flip action is no longer controlled by the operator by the hydraulic control system itself, so that the process is relatively smooth take-off and landing and security. Touchdown angle is generally 8 °~ 10 °. If itdoubles as a car door, and a result of increased platform size, angle may also be less than 8 °. At present these products to Europe and America in general. Fourth-generation products during the early 90s, and its hydraulic system and function of principles with the third-generation products, only an increase of the fuel tank the size of memory, so memory and increase the scope of action. It is different from the third generation of the product lies in the loading platform to increase its special structure, from one body to two activities connected to the platform after the touchdown, not only can automatically flip, but there is a sinking action to achieve the touchdown angle 6 °, even in 6 below. At present, the products in the Netherlands, Yugoslavia and China has applied for a utility model patent. The domestic market has been stereotyped. From the performance, security, reliability results, the fourth-generation products will be gradually replaced the second and third generation products. The first generation of products, because of its simple structure, light weight, although the technical content, but with the advantages of easy maintenance, etc., in developing countries will still have a certain market. Lifting Gear steeplechase development in China only a few things more than a decade. The former Ministry of Posts and Telecommunications in 1985 imported from Japan with a number of lifting devices steeplechase van. Since then, by the Special Purpose Vehicle Institute of Hanyang, Hubei auto parts plant andCommunication Ministry of Posts and Telecommunications Machinery Factory Mingshui three cooperation made the research and development, which lasted more than two years, due to various reasons can not be put into use. In early 1988, Ministry of Posts and Telecommunications Communications Machinery Factory Mingshui technical staff, continue to develop. Post Office in Beijing to help the strong, thanks to the efforts of the past four years, increasing product quality stabilized. Early use of domestic products as a driving force for car engines. To achieve in 1992 a car battery as the driving force of the hydraulic pump station. After 1992, lifting gear steeplechase van due to the development of domestic and began to develop, the skill level is gradually close to the international. According to the current understanding of the situation, the domestic production steeplechase of the enterprises, including Lifting Gear Mingshui, such as posts and telecommunications equipment factory at least five, the product structure have a single-cylinder, four-cylinder, five-cylinder and the early 90's and the latest U.S. technology-based The five-cylinder technology. Although the product mix in the form, the international four-generation products are produced in China, but its development is still in its infancy. The expansion of the domestic market, but also the need for inter-and opportunities. Speaking time may not last long, from the varieties ofspeaking, a short period of time will still exist a variety of forms, but in the end may be the single-cylinder and five-cylinder products.2. steeplechase of the basic principles of lifting gearLifting Gear steeplechase varieties are numerous, but the basic fundamental tenets of the original but it is the same, that is, parallel four-bar linkage of the practical application of the principle of parallel move, it is two sets of parallel four-bar linkage, sub-put longeron on both sides of car, synchronous movements, while the DCE is the above mentioned loading platform (steeplechase). Design, the following three issues to be resolved: BC under the driving force for rotation; BC under the role of rotational dynamics and the role of the form of points; CD under the C-point after touchdown, there must be a rotationaround the point D moves to E end of touchdown to facilitate loading and unloading of goods.2.1 Power SystemSteeplechase early in the development of lifting devices for the automotive engine through the oil pump driven from power-driven devices. Working hours as a result of the need to idle the engine running, is now seldom used. At present, the basic use of micro-driven hydraulic pump station, a car battery for power source. Micro-pump station has the basic components of DC motors (with the car battery voltage to match), control valves, gear pumps, combination valve(overflow, cutting one-way), and the fuel tank, electric start switch, control switch and so on. According to different vehicle battery voltage, DC motors are 12 V, 24 V are two different power according to the weight since there are 018 kW, 110 kW, 112 kW, 115 kW, 2 kW, 3 kW and so on. Gear pump according to the number of tanks (mainly hydraulic flow) and the hydraulic system pressure to choose, there is displacement 1 ml, 112 ml, 116 ml, 210 ml, 215 ml, 410 ml wide range of specifications, the maximum output pressure gear pump up to 25M Pa. Hydraulic Pump Station has been the international product quality is stable, less quality of domestic products, mainly the quality of the solenoid valve or volume too large, however.2.2 The form and the role of driving force transmission pointBoth rely on power through the pressure of hydraulic oil system from the fuel tank to the BC transmission poles. Fuel tanks and installation of the number of different positions, and to take the DC bar the difference in the rotation, the power transmission lines are also different. a1 cylinder on the front. Hinge for a long shaft B, the two parallel four-bar linkage mounted on the shaft at both ends, a shaft connected to the middle arm, then the fuel tank of the piston rod end of the fuel tank on the other side of the fixed bracket on the transmission of power as follows: oil tumbler cylinder → → BC rod shaft, the working process in Figure 2. b1 on the rear cylinder. The fuel tank24 is located in the middle of linkage, the two four-bar linkage in the middle of the BC bar with fixed beams together, the middle beam connecting rod and the fuel tank, fuel tank connected to the other side with the stent. c1 four-cylinder and five-cylinder type. Five-cylinder structure of the memory of the fifth hydraulic cylinder is a cylinder in the hydraulic circuit, the loading platform to participate in only touchdown after the reversal platform action, without reference platform for take-off and landing, and its basic structure with the same four-cylinder. Four-cylinder under the structure of the fuel tank of BC, which is different from the distinction between single-cylinder.2.3 CD under the rotationCD of the rotation pole, four-cylinder with five-cylinder fuel tank of the type of contraction depend on the realization of single-cylinder rear-mounted on, CD can not be achieved under rotation (but can be reversed to achieve at the highest position, because the structure of more complex, and I shall not introduce) ; for the single-cylinder front-on, based on the structural changes under BC achievable. The actual design, AD is also required under certain technical processing to meet the requirements. In addition, note that, D CE articulated only in the D point, the other type for the D, C two hinged.3 steeplechase lifting device to determine the technical parametersLifting Gear steeplechase main technical parameters: Rated lifting the quality of travel movements, take-off and landing speed, shot size, platform size, operating voltage and power motor, gear pump row weight (rated output flow), control valves, the type and quantity of and the fuel tank of the bore and stroke, rated working pressure. Under normal circumstances, the beginning of the design parameters are known to width and height from the floor, battery voltage and capacity, beam spacing and beam auto height and size of rear overhang. Known p a r a m e t e r s a r e t h e f u n d a m e n t a l b a s i s f o r d e s i g n.栏板起重装置的结构与设计相对传统的举升机构,该尾板举升机构只采用了单油缸,使液压系统的管路简单,控制方便,液压系统的可靠性高,且安装方便。
机械毕业设计英文外文翻译72车架
附录附录AThe frame is the most basic test bench car, all the suspension and turned to connect components are installed in frame above. If car frame flexible is too big, can make cars can neither turned, also cannot normal control. And if the car too rigid frame structure, and would cause unnecessary vibration passed to the driver and passenger's seat cabins. Auto frame and suspension structure design is not only the vehicle noise size and the decision of the vibration amplitude strength, but also will affect the quality of the car and the normal control vehicle. Car manufacturers in their production car are used in several different frame structure. Among them, through the seventy s the most commonly used is shell and girders of fission structure.At present it is still in large trucks, small tonnage truck and a truck on the application. In car shell and the beam structure in the fission, engine, transmission device, transmission gear and the car is through shell insulation devices in the body on the sole fixed. The frame of the internal insulation devices is artificial rubber pad to be able to stop road uneven and engine noise and vibration of the work related to the driver and passenger's cockpit. The second isthe single structure of automobile frame. This kind of design so far in the modern car is the most commonly used. According to the strength of the frame monomer to points, design have light structure. In this car structure as part of the beam frame welding to be directly on the shell. The weight of the chassis increased the strength of the beam. Transmission gears and transmission device via big and soft artificial rubber insulation mat installed in the frame monomer. Insulation pad weakened the noise transmission and vibration. If the insulation pad too soft, will cause transmission gears and transmission device displacement. The displacement called soft quantity, it will affect the manipulation of car performance and control performance. If the insulation pad too hard, cannot play its isolation and reduce the role of the vibration noise. Car manufacturers well-designed insulation mat, put them in proper place device car, in order to reduce the noise, vibration, make the transmission buffer for driving car, drivers and passengers take comfort. The performance of the insulation mat with use fixed number of year changing, when the old car becomes the performance of the original also changed.He third kind of structure is the first two kinds of structure of the main characteristics unifies in together. It in front of the car used car beam, in the short HouCang use a frame. A monomer, and shortrigid part of the beam's action is insulation to enhance the car.Car manufacturers in the car that choose low production cost and at the same time to meet with noise, vibration control performance requirements of high driving frame structure. The old large vehicles, trucks, and trucks often use shell and girders of fission structure. A new, smaller vehicles often use single structure frame.Engine piston connecting rod groupThe piston connecting rod group of piston, piston, piston pins, connecting rod, connecting rod bearings etc.Function: the piston is the work of gas pressure to bear, and through the piston pin to connecting rod rotation, the piston driven crankshaft top or part of the combustion chamber. Working conditions: the piston in high temperature and high pressure, high speed, bad lubrication under the conditions of the job. The piston directly with high temperature, gas contact instantaneous temperatures up to 2500 K above, therefore, heat, and cooling conditions and serious is very poor, so the piston work temperature is very high, the top as high as 600 to 700 K, and the temperature distribution is not uniform; The piston top bear gas pressure to do work, especially the greatest pressure, the gasoline engine trip up to 3 ~ 5 MPa, diesel engine as high as 6 ~ 9 MPa, this makes the piston impact, and bear the role of the lateral pressure, therefore,the piston should have enough heat resistance, to try to reduce the piston, piston cooling heating strengthen heat transfer surface, suitable enlargement, make the tops of the pistons. The highest temperature drop Inside the cylinder piston at high speed (8 to 12 m/s) reciprocating motion, and speed changing constantly, which has made a big inertia force, driving the piston is much additional load. The piston in this harsh conditions, can produce deformation work and accelerated wear, still can produce additional load and thermal stress, and the chemical corrosion function by gas. In order to reduce reciprocating inertia force, must reduce the weight of the piston as much as possible. The piston is in high temperature and high pressure, high speed (piston average speed can reach 101115 m/s) under the working conditions of the poor, the lubrication, piston and cylinder wall friction between serious. To reduce the friction, the piston surface must wear-resisting. Requirements:1)To have enough stiffness and strength, power transmission and reliable;2)Thermal conductivity, resistance to high pressure, high temperature resistant, wear resistance;3) Quality, light weight, small to minimize reciprocating inertia force. Aluminum alloy material basically meet the above requirements,therefore, the piston typically use the high-strength aluminum alloy, but in some low speed diesel engine USES the senior cast iron or heat resistant steel.Suspension systemSuspension shock absorbers and control including a spring, connecting rod device. It must be able to support the body weight and enough to load. Suspension also should be able to withstand the engine and braking to it an opposite reaction. Suspension system is the most important function of the tire and road surface contact time as far as possible the long. In support of body and load, even in rough roads should be more so. The four tire tread come in contact with the car is the only part. All output power, engine to force and power system through come in contact with the pavement of the tire tread work. Whenever tires and road surface contact or car started when the car skid, control ability (power, to force, braking force) will be weakened or even lost.Car body is supported by spring, spring can be divided into the spiral, steel plate type, twist bar type and inflatable. The spiral spring is the most widely used in modern car type. The spiral, torsion bar type and inflatable spring is need to use the connecting rod and connecting with the wheel arm in place. Leaf spring provide the horizontal and vertical vehicle control, in order to prevent thecar wheel in cars, they often unnecessary displacement with truck in the van and truck.Suspension system is along with the development of the passenger car and change and improvement. A luxury car, special vehicle, small cars and light trucks are designed completely different. Modern tire improvement continuously improve the vehicles operating performance, it is the improvement and shock absorbers, steering system and suspension control device of synchronous improvement together.In modern car of the manipulation conditions need to tires and the road, so that safe, correct contact to control and motor vehicles. To want to maximum driving safety, to remember this four tires must in any time and the road phase contact. At the same time to consider the vehicle steering flexibility, tire wear resistance, automobile driving comfort and driving safety, in order to achieve the effective control of the car. Suspension system is divided into front suspension and after suspension.The front suspension design has been rapid development. From relatively coarse hard shaft structure to the development of the modern light, high strength, support type independent suspension structure, and by increasing the connecting rod device and make the car's performance is improved. Suspension structure isimproved with the improvement of the road, and drivers need and the improvements.Most lead the engine, rear wheel drive car USES a simple after the dependency of the suspension. But a rear wheel drive independent suspension structure is complex, and high cost, and only used for a bus.To lead the engine of the car front wheel drive, through the transmission device, moved to the front suspension after only used to regulate driving control and the reaction of braking. This has the simplified of independent suspension institutions, half independent suspension institutions and independent suspension after the application, the latter a large institutions used in the design of the structure of new vehicles.附录B车架是汽车最基本的台架，所有的悬架和转向连接部件都安装在车架上面。
机械毕业设计英文外文翻译345起重机介绍
附录外文文献原文：The Introduction of cranesA crane is defined as a mechanism for lifting and lowering loads with a hoisting mechanism Shapiro, 1991. Cranes are the most useful and versatile piece of equipment on a vast majority of construction projects. They vary widely in configuration, capacity, mode of operation, intensity of utilization and cost. On a large project, a contractor may have an assortment of cranes for different purposes. Small mobile hydraulic cranes may be used for unloading materials from trucks and for small concrete placement operations, while larger crawler and tower cranes may be used for the erection and removal of forms, the installation of steel reinforcement, the placement of concrete, and the erection of structural steel and precast concrete beams.On many construction sites a crane is needed to lift loads such as concrete skips, reinforcement, and formwork. As the lifting needs of the construction industry have increased and diversified, a large number of general and special purpose cranes have been designed and manufactured. These cranes fall into two categories, those employed in industry and those employed in construction. The most common types of cranes used in construction are mobile, tower, and derrick cranes.1.Mobile cranesA mobile crane is a crane capable of moving under its own power without being restricted to predetermined travel. Mobility is provided by mounting or integrating the crane with trucks or all terrain carriers or rough terrain carriers or by providing crawlers. Truck-mounted cranes have the advantage of being able to move under their own power to the construction site. Additionally, mobile cranes can move about the site, and are often able to do the work of several stationary units.Mobile cranes are used for loading, mounting, carrying large loads and for work performed in the presence of obstacles of various kinds such as power lines and similar technological installations. The essential difficulty is here the swinging of the payload which occurs during working motion and also after the work is completed. This applies particularly to the slewing motion of the crane chassis, for which relatively large angular accelerations and negative accelerations of the chassis are characteristic. Inertia forces together with the centrifugal force and the Carioles force cause the payload to swing as a spherical pendulum. Proper control of the slewing motion of the crane serving to transport a payload to the defined point with simultaneous minimization of the swings when theworking motion is finished plays an important role in the model.Modern mobile cranes include the drive and the control systems. Control systems send the feedback signals from the mechanical structure to the drive systems. In general, they are closed chain mechanisms with flexible members [1].Rotation, load and boom hoisting are fundamental motions the mobile crane. During transfer of the load as well as at the end of the motion process, the motor drive forces, the structure inertia forces, the wind forces and the load inertia forces can result in substantial, undesired oscillations in crane. The structure inertia forces and the load inertia forces can be evaluated with numerical methods, such as the finite element method. However, the drive forces are difficult to describe. During start-up and breaking the output forces of the drive system significantly fluctuate. To reduce the speed variations during start-up and braking the controlled motor must produce torque other than constant [2,3], which in turn affects the performance of the crane.Modern mobile cranes that have been built till today have oft a maximal lifting capacity of 3000 tons and incorporate long booms. Crane structure and drive system must be safe, functionary and as light as possible. For economic and time reasons it is impossible to build prototypes for great cranes. Therefore, it is desirable to determinate the crane dynamic responses with the theoretical calculation.Several published articles on the dynamic responses of mobile crane are available in the open literature. In the mid-seventies Peeken et al. [4] have studied the dynamic forces of a mobile crane during rotation of the boom, using very few degrees of freedom for the dynamic equations and very simply spring-mass system for the crane structure. Later Maczynski et al. [5] studied the load swing of a mobile crane with a four mass-model for the crane structure. Posiadala et al. [6] have researched the lifted load motion with consideration for the change of rotating, booming and load hoisting. However, only the kinematics were studied. Later the influence of the flexibility of the support system on the load motion was investigated by the same author [7]. Recently, Kilicaslan et al. [1] have studied the characteristics of a mobile crane using a flexible multibody dynamics approach. Towarek [16] has concentrated the influence of flexible soil foundation on the dynamic stability of the boom crane. The drive forces, however, in all of those studies were presented by using so called the method of ‘‘kinematics forcing’’ [6] with a ssumed velocities or accelerations. In practice this assumption could not comply with the motion during start-up and braking.A detailed and accurate model of a mobile crane can be achieved with the finite element method. Using non-linear finite element theory Gunthner and Kleeberger [9] studied the dynamic responses of lattice mobile cranes. About 2754 beam elements and 80 truss elements were used for modeling of the lattice-boom structure. On this basis a efficient software for mobile crane calculation––NODYA has been developed. However, theinfluences of the drive systems must be determined by measuring on hoisting of the load [10], or rotating of the crane [11]. This is neither efficient nor convenient for computer simulation of arbitrary crane motions.Studies on the problem of control for the dynamic response of rotary crane are also available. Sato et al. [14], derived a control law so that the transfer a load to a desired position will take place that at the end of the transfer of the swing of the load decays as soon as possible. Gustafsson [15] described a feedback control system for a rotary crane to move a cargo without oscillations and correctly align the cargo at the final position. However, only rigid bodies and elastic joint between the boom and the jib in those studies were considered. The dynamic response of the crane, for this reason, will be global.To improve this situation, a new method for dynamic calculation of mobile cranes will be presented in this paper. In this method, the flexible multibody model of the steel structure will be coupled with the model of the drive systems. In that way the elastic deformation, the rigid body motion of the structure and the dynamic behavior of the drive system can be determined with one integrated model. In this paper this method will be called ‘‘complete dynamic calculation for driven“mechanism”.On the basis of flexible multibody theory and the Lagrangian equations, the system equations for complete dynamic calculation will be established. The drive- and control system will be described as differential equations. The complete system leads to a non-linear system of differential equations. The calculation method has been realized for a hydraulic mobile crane. In addition to the structural elements, the mathematical modeling of hydraulic drive- and control systems is decried. The simulations of crane rotations for arbitrary working conditions will be carried out. As result, a more exact representation of dynamic behavior not only for the crane structure, but also for the drive system will be achieved. Based on the results of these simulations the influences of the accelerations, velocities during start-up and braking of crane motions will be discussed.2.Tower cranesThe tower crane is a crane with a fixed vertical mast that is topped by a rotating boom and equipped with a winch for hoisting and lowering loads (Dickie, 990). Tower cranes are designed for situations which require operation in congested areas. Congestion may arise from the nature of the site or from the nature of the construction project. There is no limitation to the height of a high-rise building that can be constructed with a tower crane. The very high line speeds, up to 304.8 mrmin, available with some models yield good production rates at any height. They provide a considerable horizontal working radius, yet require a small work space on the ground (Chalabi, 1989). Some machines can also operate in winds of up to 72.4 km/h, which is far above mobile crane wind limits.The tower cranes are more economical only for longer term construction operations and higher lifting frequencies. This is because of the fairly extensive planning needed forinstallation, together with the transportation, erection and dismantling costs.3. Derrick cranesA derrick is a device for raising, lowering, and/or moving loads laterally. The simplest form of the derrick is called a Chicago boom and is usually installed by being mounted to building columns or frames during or after construction (Shapiro and Shapiro, 1991).This derrick arrangement. (i.e., Chicago boom) becomes a guy derrick when it is mounted to a mast and a stiff leg derrick when it is fixed to a frame.The selection of cranes is a central element of the life cycle of the project. Cranes must be selected to satisfy the requirements of the job. An appropriately selected crane contributes to the efficiency, timeliness, and profitability of the project. If the correct crane selection and configuration is not made, cost and safety implications might be created (Hanna, 1994). Decision to select a particular crane depends on many input parameters such as site conditions, cost, safety, and their variability. Many of these parameters are qualitative, and subjective judgments implicit in these terms cannot be directly incorporated into the classical decision making process. One way of selecting crane is achieved using fuzzy logic approach.Cranes are not merely the largest, the most conspicuous, and the most representative equipment of construction sites but also, at various stages of the project, a real “bottleneck” that slows the pace of the construction process. Although the crane can be found standing idle in many instances, yet once it is involved in a particular task ,it becomes an indispensable link in the activity chain, forcing at least two crews(in the loading and the unloading zones) to wait for the service. As analyzed in previous publications [6-8] it is feasible to automate (or, rather, semi-automate) crane navigation in order to achieve higher productivity, better economy, and safe operation. It is necessary to focus on the technical aspects of the conversion of existing crane into large semi-automatic manipulators. By mainly external devices mounted on the crane, it becomes capable of learning, memorizing, and autonomously navigation to reprogrammed targets or through prêt aught paths.The following sections describe various facets of crane automation:First, the necessary components and their technical characteristics are reviewed, along with some selection criteria. These are followed by installation and integration of the new components into an existing crane. Next, the Man –Machine –Interface (MMI) is presented with the different modes of operation it provides. Finally, the highlights of a set of controlled tests are reported followed by conclusions and recommendations.Manual versus automatic operation: The three major degrees of freedom of common tower cranes are illustrated in the picture. In some cases , the crane is mounted on tracks , which provi de a fourth degree of freedom , while in other cases the tower is “telescope” or extendable , and /or the “jib” can be raised to a diagonal position. Since these additionaldegrees of freedom are not used routinely during normal operation but rather are fixed in a certain position for long periods (days or weeks), they are not included in the routine automatic mode of operation, although their position must be “known” to the control system.外文文献中文翻译：起重机介绍起重机是用来举升机构、抬起或放下货物的器械。
机械外文文献翻译----起重机调度与空间限制
毕业设计方案中起重机的英文翻译
The Use and History of CraneEvery time we see a crane in action we remains without words, these machines are sometimes really huge, taking up tons of material hundreds of meters in height. We watch with amazement and a bit of terror, thinking about what would happen if the load comes off or if the movement of the crane was wrong. It is a really fascinating system, surprising both adults and children. These are especially tower cranes, but in reality there are plenty of types and they are in use for centuries. The cranes are formed by one or more machines used to create a mechanical advantage and thus move large loads. Cranes are equipped with a winder, a wire rope or chain and sheaves that can be used both to lift and lower materials and to move them horizontally. It uses one or more simple machines to create mechanical advantage and thus move loads beyond the normal capability of a human. Cranes are commonly employed in the transport industry for the loading and unloading of freight, in the construction industry for the movement of materials and in the manufacturing industry for the assembling of heavy equipment.1. OverviewThe first construction cranes were invented by the Ancient Greeks and were powered by men or beasts of burden, such as donkeys. These cranes were used forthe construction of tall buildings. Larger cranes were later developed, employing the use of human treadwheels, permitting the lifting of heavier weights. In the High Middle Ages, harbor cranes were introduced to load and unload ships and assist with their construction –some were built into stone towers for extra strength and stability. The earliest cranes were constructed from wood, but cast iron and steel took over with the coming of the Industrial Revolution.For many centuries, power was supplied by the physical exertion of men or animals, although hoists in watermills and windmills could be driven by the harnessed natural power. The first 'mechanical' power was provided by steam engines, the earliest steam crane being introduced in the 18th or 19th century, with many remaining in use well into the late 20th century. Modern cranes usually use internal combustion engines or electric motors and hydraulic systems to provide a much greater lifting capability than was previously possible, although manual cranes are still utilized where the provision of power would be uneconomic.Cranes exist in an enormous variety of forms –each tailored to a specific use. Sizes range from the smallest jib cranes, used inside workshops, to the tallest tower cranes, used for constructing high buildings. For a while, mini - cranes are also used for constructing high buildings, in order tofacilitate constructions by reaching tight spaces. Finally, we can find larger floating cranes, generally used to build oil rigs and salvage sunken ships. This article also covers lifting machines that do not strictly fit the above definition of a crane, but are generally known as cranes, such as stacker cranes and loader cranes.2. HistoryAncient GreeceThe crane for lifting heavy loads was invented by the Ancient Greeks in the late 6th century BC. The archaeological record shows that no later than c.515 BC distinctive cuttings for both lifting tongs and lewis irons begin to appear on stone blocks of Greek temples. Since these holes point at the use of a lifting device, and since they are to be found either above the center of gravity of the block, or in pairs equidistant from a point over the center of gravity, they are regarded by archaeologists as the positive evidence required for the existence of the crane.The introduction of the winch and pulley hoist soon lead to a widespread replacement of ramps as the main means of vertical motion. For the next two hundred years, Greek building sites witnessed a sharp drop in the weights handled, as the new lifting technique made the use of several smaller stones more practical than of fewer larger ones. In contrast to the archaic period with its tendency to ever-increasing block sizes, Greek temples of theclassical age like the Parthenon invariably featured stone blocks weighing less than 15-20 tons. Also, the practice of erecting large monolithic columns was practically abandoned in favor of using several column drums.Although the exact circumstances of the shift from the ramp to the crane technology remain unclear, it has been argued that the volatile social and political conditions of Greece were more suitable to the employment of small, professional construction teams than of large bodies of unskilled labor, making the crane more preferable to the Greek polis than the more labor-intensive ramp which had been the norm in the autocratic societies of Egypt or Assyria.The first unequivocal literary evidence for the existence of the compound pulley system appears in the Mechanical Problems (Mech. 18, 853a32-853b13> attributed to Aristotle (384-322 BC>, but perhaps composed at a slightly later date. Around the same time, block sizes at Greek temples began to match their archaic predecessors again, indicating that the more sophisticated compound pulley must have found its way to Greek construction sites by then.Ancient RomeThe heyday of the crane in ancient times came during the Roman Empire, when construction activity soared and buildings reached enormous dimensions. The Romans adopted the Greek crane and developed it further. We are relatively well informed about theirlifting techniques, thanks to rather lengthy accounts by the engineers Vitruvius (De Architectura 10.2, 1-10> and Heron of Alexandria (Mechanica 3.2-5>. There are also two surviving reliefs of Roman treadwheel cranes, with the Haterii tombstone from the late first century AD being particularly detailed.The simplest Roman crane, the Trispastos, consisted of a single-beam jib, a winch, a rope, and a block containing three pulleys. Having thus a mechanical advantage of 3:1, it has been calculated that a single man working the winch could raise 150 kg (3 pulleys x 50 kg = 150>, assuming that 50 kg represent the maximum effort a man can exert over a longer time period. Heavier crane types featured five pulleys (Pentaspastos> or, in case of the largest one, a set of three by five pulleys (Polyspastos> and came with two, three or four masts, depending on the maximum load. The Polyspastos, when worked by four men at both sides of the winch, could already lift 3000 kg (3 ropes x 5 pulleys x 4 men x 50 kg = 3000 kg>. In case the winch was replaced by a treadwheel, the maximum load even doubled to 6000 kg at only half the crew, since the treadwheel possesses a much bigger mechanical advantage due to its larger diameter. This meant that, in comparison to the construction of the Egyptian Pyramids, where about 50 men were needed to move a 2.5 ton stone block up the ramp (50 kg per person>, the lifting capability ofthe Roman Polyspastos proved to be 60 times higher (3000 kg per person>.However, numerous extant Roman buildings which feature much heavier stone blocks than those handled by the Polyspastos indicate that the overall lifting capability of the Romans went far beyond that of any single crane. At the temple of Jupiter at Baalbek, for instance, the architrave blocks weigh up to 60 tons each, and one corner cornice block even over 100 tons, all of them raised to a height of about 19 m. In Rome, the capital block of Trajan's Column weighs 53.3 tons, which had to be lifted to a height of about 34 m (see construction of Trajan's Column>.It is assumed that Roman engineers lifted these extraordinary weights by two measures (see picture below for comparable Renaissance technique>: First, as suggested by Heron, a lifting tower was set up, whose four masts were arranged in the shape of a quadrangle with parallel sides, not unlike a siege tower, but with the column in the middle of the structure (Mechanica 3.5>. Second, a multitude of capstans were placed on the ground around the tower, for, although having a lower leverage ratio than treadwheels, capstans could be set up in higher numbers and run by more men (and, moreover, by draught animals>. This use of multiple capstans is also described by Ammianus Marcellinus (17.4.15> in connection with the lifting of the Lateranense obelisk in the Circus Maximus (ca. 357 AD>. Themaximum lifting capability of a single capstan can be established by the number of lewis iron holes bored into the monolith. In case of the Baalbek architrave blocks, which weigh between 55 and 60 tons, eight extant holes suggest an allowance of 7.5 ton per lewis iron, that is per capstan. Lifting such heavy weights in a concerted action required a great amount of coordination between the work groups applying the force to the capstans.Middle AgesDuring the High Middle Ages, the treadwheel crane was reintroduced on a large scale after the technology had fallen into disuse in western Europe with the demise of the Western Roman Empire. The earliest reference to a treadwheel (magna rota> reappears in archival literature in France about 1225, followed by an illuminated depiction in a manuscript of probably also French origin dating to 1240. In navigation, the earliest uses of harbor cranes are documented for Utrecht in 1244, Antwerp in 1263, Brugge in 1288 and Hamburg in 1291, while in England the treadwheel is not recorded before 1331.Generally, vertical transport could be done more safely and inexpensively by cranes than by customary methods. Typical areas of application were harbors, mines, and, in particular, building sites where the treadwheel crane played a pivotal role in the construction of the lofty Gothic cathedrals. Nevertheless, both archival and pictorial sources ofthe time suggest that newly introduced machines like treadwheels or wheelbarrows did not completely replace more labor-intensive methods like ladders, hods and handbarrows. Rather, old and new machinery continued to coexist on medieval construction sites and harbors.Apart from treadwheels, medieval depictions also show cranes to be powered manually by windlasses with radiating spokes, cranks and by the 15th century also by windlasses shaped like a ship's wheel. To smooth out irregularities of impulse and get over 'dead-spots' in the lifting process flywheels are known to be in use as early as 1123.The exact process by which the treadwheel crane was reintroduced is not recorded, although its return to construction sites has undoubtedly to be viewed in close connection with the simultaneous rise of Gothic architecture. The reappearance of the treadwheel crane may have resulted from a technological development of the windlass from which the treadwheel structurally and mechanically evolved. Alternatively, the medieval treadwheel may represent a deliberate reinvention of its Roman counterpart drawn from Vitruvius' De architectura which was available in many monastic libraries. Its reintroduction may have been inspired, as well, by the observation of the labor-saving qualities of the waterwheel with which early treadwheels shared many structural similarities.Structure and placementThe medieval treadwheel was a large wooden wheel turning around a central shaft with a treadway wide enough for two workers walking side by side. While the earlier 'compass-arm' wheel had spokes directly driven into the central shaft, the more advanced 'clasp-arm' type featured arms arranged as chords to the wheel rim, giving the possibility of using a thinner shaft and providing thus a greater mechanical advantage.Contrary to a popularly held belief, cranes on medieval building sites were neither placed on the extremely lightweight scaffolding used at the time nor on the thin walls of the Gothic churches which were incapable of supporting the weight of both hoisting machine and load. Rather, cranes were placed in the initial stages of construction on the ground, often within the building. When a new floor was completed, and massive tie beams of the roof connected the walls, the crane was dismantled and reassembled on the roof beams from where it was moved from bay to bay during construction of the vaults. Thus, the crane ‘grew’ and ‘wandered’ with the building with the result that today all extant construction cranes in England are found in church towers above the vaulting and below the roof, where they remained after building construction for bringing material for repairs aloft.Less frequently, medieval illuminations also show cranes mounted on the outside of walls with the stand of the machine secured to putlogs.Mechanics and operationIn contrast to modern cranes, medieval cranes and hoists - much like their counterparts in Greece and Rome - were primarily capable of a vertical lift, and not used to move loads for a considerable distance horizontally as well. Accordingly, lifting work was organized at the workplace in a different way than today. In building construction, for example, it is assumed that the crane lifted the stone blocks either from the bottom directly into place, or from a place opposite the centre of the wall from where it could deliver the blocks for two teams working at each end of the wall. Additionally, the crane master who usually gave orders at the treadwheel workers from outside the crane was able to manipulate the movement laterally by a small rope attached to the load. Slewing cranes which allowed a rotation of the load and were thus particularly suited for dockside work appeared as early as 1340. While ashlar blocks were directly lifted by sling, lewis or devil's clamp (German Teufelskralle>, other objects were placed before in containers like pallets, baskets, wooden boxes or barrels.It is noteworthy that medieval cranes rarely featured ratchets or brakes to forestall the load from running backward. This curious absence isexplained by the high friction force exercised by medieval treadwheels which normally prevented the wheel from accelerating beyond control.Harbor usageAccording to the "present state of knowledge" unknown in antiquity, stationary harbor cranes are considered a new development of the Middle Ages. The typical harbor crane was a pivoting structure equipped with double treadwheels. These cranes were placed docksides for the loading and unloading of cargo where they replaced or complemented older lifting methods like see-saws, winches and yards.Two different types of harbor cranes can be identified with a varying geographical distribution: While gantry cranes which pivoted on a central vertical axle were commonly found at the Flemish and Dutch coastside, German sea and inland harbors typically featured tower cranes where the windlass and treadwheels were situated in a solid tower with only jib arm and roof rotating. Interestingly, dockside cranes were not adopted in the Mediterranean region and the highly developed Italian ports where authorities continued to rely on the more labor-intensive method of unloading goods by ramps beyond the Middle Ages.Unlike construction cranes where the work speed was determined by the relatively slow progress of the masons, harbor cranes usually featured double treadwheels to speed up loading. The two treadwheelswhose diameter is estimated to be 4 m or larger were attached to each side of the axle and rotated together. Today, according to one survey, fifteen treadwheel harbor cranes from pre-industrial times are still extant throughout Europe.[28] Beside these stationary cranes, floating cranes which could be flexibly deployed in the whole port basin came into use by the 14th century.RenaissanceA lifting tower similar to that of the ancient Romans was used to great effect by the Renaissance architect Domenico Fontana in 1586 to relocate the 361 t heavy Vatican obelisk in Rome. From his report, it becomes obvious that the coordination of the lift between the various pulling teams required a considerable amount of concentration and discipline, since, if the force was not applied evenly, the excessive stress on the ropes would make them rupture.Early modern ageCranes were used domestically in the 17th and 18th century. The chimney or fireplace crane was used to swing pots and kettles over the fire and the height was adjusted by a trammel.3. Mechanical principlesThere are two major considerations in the design of cranes. The first is that the crane must be able to lift a load of a specified weight and the second is that the crane must remain stable and not toppleover when the load is lifted and moved to another location.Lifting capacityCranes illustrate the use of one or more simple machines to create mechanical advantage.•The lever. A balance crane contains a horizontal beam (the lever> pivoted about a point called the fulcrum. The principle of the lever allows a heavy load attached to the shorter end of the beam to be lifted by a smaller force applied in the opposite direction to the longer end of the beam. The ratio of the load's weight to the applied force is equal to the ratio of the lengths of the longer arm and the shorter arm, and is called the mechanical advantage.•The pulley. A jib crane contains a tilted strut (the jib> that supports a fixed pulley block.Cables are wrapped multiple times round the fixed block and round another block attached to the load. When the free end of the cable is pulled by hand or by a winding machine, the pulley system delivers a force to the load that is equal to the applied force multiplied by the number of lengths of cable passing between the two blocks. This number is the mechanical advantage.•The hydraulic cylinder. This can be used directly to lift the load or indirectly to move the jib or beam that carries another lifting device.Cranes, like all machines, obey the principle of conservation of energy. This means that the energy delivered to the load cannot exceed the energy put into the machine. For example, if a pulley system multiplies the applied force by ten, then the load moves only one tenth as far as the applied force. Since energy is proportional to force multiplied by distance, the output energy is kept roughly equal to the input energy (in practice slightly less, because some energy is lost to friction and other inefficiencies>.StabilityFor stability, the sum of all moments about any point such as the base of the crane must equate to zero. In practice, the magnitude of load that is permitted to be lifted (called the "rated load" in the US> is some value less than the load that will cause the crane to tip (providing a safety margin>.Under US standards for mobile cranes, the stability-limited rated load for a crawler crane is 75% of the tipping load. The stability-limited rated load for a mobile crane supported on outriggers is 85% of the tipping load. These requirements, along with additional safety-related aspects of crane design, are established by the American Society of Mechanical Engineers in the volume ASME B30.5-2007 Mobile and Locomotive Cranes.Standards for cranes mounted on ships or offshore platforms are somewhat stricter because of thedynamic load on the crane due to vessel motion. Additionally, the stability of the vessel or platform must be considered.For stationary pedestal or kingpost mounted cranes, the moment created by the boom, jib, and load is resisted by the pedestal base or kingpost. Stress within the base must be less than the yield stress of the material or the crane will fail.4. Types of the cranesMobileMain article: Mobile craneThe most basic type of mobile crane consists of a truss or telescopic boom mounted on a mobile platform - be it on road, rail or water.FixedExchanging mobility for the ability to carry greater loads and reach greater heights due to increased stability, these types of cranes are characterized that they, or at least their main structure does not move during the period of use. However, many can still be assembled and disassembled.5. Overhead CranesUseThe most common overhead crane use is in the steel industry. Every step of steel, until it leaves a factory as a finished product, the steel is handled by an overhead crane. Raw materials are poured into a furnace by crane, hot steel is stored for cooling by an overhead crane, the finished coils are lifted andloaded onto trucks and trains by overhead crane, and the fabricator or stamper uses an overhead crane to handle the steel in his factory. The automobile industry uses overhead cranes for handling of raw materials. Smaller workstation cranes handle lighter loads in a work-area, such as CNC mill or saw.HistoryAlton Shaw, of the Shaw Crane Company, is credited with the first overhead crane, in 1874. Alliance Machine, now defunct, holds an AISE citation for one of the earliest cranes as well. This crane was in service until approximately 1980, and is now in a museum in Birmingham, Alabama. Over the years important innovations, such as the Weston load brake (which is now rare> and the wire rope hoist (which is still popular>, have come and gone. The original hoist contained components mated together in what is now called the built-up style hoist. These built up hoists are used for heavy-duty applications such as steel coil handling and for users desiring long life and better durability. They also provide for easier maintenance. Now many hoists are package hoists, built as one unit in a single housing, generally designed for ten-year life or less.Notable cranes and dates•1874: Alton Shaw develops t he first overhead crane.•1938: Yale introduces the Cable-King hoist.•1944: Shepard-Niles supplies a hoist for lifting atomic bombs for testing in New Mexico.•1969: Power Electronics International, Inc. developed the overhead hoist variable speed drive. •1983: The world's biggest overhead crane from Bardella Company starts its operation at Itaipu dam Hydro Power Plant Brazil.•1997: Industry giant P&H files for chapter eleven bankruptcy. Later renamed Morris Material Handling but still using the P&H tradename, they again went bankrupt.•1998: Dearborn Crane supplies two 500-ton capacity overhead cranes to Verson Press of Chicago. The cranes were never used due to Verson's bankruptcy.。
机械毕业设计英文外文翻译579重型汽车驱动桥的基本结构及发展趋势
机械毕业设计英文外文翻译579重型汽车驱动桥的基本结构及发展趋势The Basic Structure and Development Trend of Heavy-Duty Automotive Drive AxlesKeywords: heavy-duty automotive, drive axle, structure, development trend1. IntroductionThe drive axle plays a crucial role in heavy-duty automotive systems, as it is responsible for transmitting power from the engine to the wheels. Over the years, significant improvements have been made in the design, structure, and materials of drive axles to meet the increasing demands for vehicle performance, efficiency, and durability. This paper aims to analyze the basic structure of heavy-duty automotive drive axles and explore their development trend.2. Traditional Drive Axle Structure2.1 Axle Housing2.2 DifferentialThe differential distributes power evenly between the left and right wheels, enabling smooth turning and preventing wheel slippage. It consists of bevel gears and a pinion gear, ensuring power transmission at different speeds and loads.2.3 Gears2.4 Bearings3. Development Trend3.1 Lightweight MaterialsThe adoption of lightweight materials in the construction of drive axles is a significant trend. This helps in reducing the overall weight of the vehicle, improving fuel efficiency and load capacity, and enhancing vehicle performance.3.2 Electronic Control Systems3.3 Advanced Manufacturing Techniques4. Challenges and OpportunitiesThe development of heavy-duty automotive drive axles faces several challenges, such as meeting increasingly stringent emission regulations, improving energy efficiency, and addressing the demand for autonomous driving capabilities. However, these challenges also bring opportunities, such as the development of hybrid and electric drive axles, as well as the integration of connectivity and intelligent control systems.5. Conclusion。
车辆工程专业 毕业设计外文翻译5
TransmissionsTransmissions have to compromise on either ride comfort or efficiency, but a new approach to the dog engagement gearbox could improve both.With tightening emissions regulations, carmakers are not just confining their efforts to improving combustion and after-treatment. Many are finding that modern engines are so advanced that the benefits of some engine technologies are small compared to the huge development costs involved.It's important to look at the whole vehicle in order to improve emissions. As the second most expensive piece of kit in the car, the transmission is the logical next place to look.Of all transmission technologies, the manual gearbox is the most efficient; around 96percent of the energy that is put in comes out of the other end. But not everyone can drive one or wants to. Because you have to dip the clutch pedal, it's less comfortable to drive in heavy traffic. It makes the driver tired and the torque interruptions' head-nod effect on passengers can be wearing.The driver's clutch control and corresponding torque interruptions are also the manual's weak point. When accelerating up through the gearbox, each up-shift requires the driver to cut the torque momentarily by lifting the gas pedal and dipping the clutch. It may just take a second to complete the operation, but during this time the vehicle is losing speed and acceleration.At the opposite and of the spectrum is the traditional automatic. Its shift quality is good thanks to its torque converter, but efficiency is relatively poor despite recent advances. Because of this ,a lot of the current research is trying to find an efficient alternative to the conventional automatic.The main technologies are continuously variable transmissions (CVTs); dual clutch transmissions(DCTs) and automated manual transmissions(AMTs).They all offer different benefits over the conventional planetary automatic.The CVT uses a belt chain or toroidal shaped dish drive to vary an infinite number of gear ratios. It has improved efficiency and cost when compared to conventional automatics.Its advantage comes from its simplicitu. It consists of very few components; usually a rubber or metal-link belt; a hydraulically operated driving pulley, a mechanical torque-sensing driving pulley, microprocessors and some sensors.The transmissions works by varying the distance between the faces of the two main pulleys.The pulleys have V-shaped grooves in which the connecting belt rides. One side of the pulley is fixed axially; the other side moves, actuated by hydraulics.When actuatec, the cylinder can increase or reduce the amount of space between the two sides of the pulley. This allows the belt to ride lower or higher along the walls of the pulley, depending on driving conditions. This changes the gear ratio. A torodial-type design works in a similar way but runs on discs and power-rollers.The "stepless" nature of its design is CVT's biggest draw for automotive engineers. Because of this, a CVT can work to keep the engine in its optimum power range, thereby increasing efficiency and mileage. A CVT can convert every point on theengine's operating curve to a corresponding point on its own operating curve.The transmission is most popular with Japanese carmakers and Japanese supplier JATCO is a major producer. But in the US and Europe driving styles are different. Uptake has been slow despite Audi and other manufacturers having offered CVT otions on their ranges.The DCT is, in effect, two manual gearboxes coupled together. Gear shifts are made by switching from one clutch on one gearbox to another clutch on the other. The shift quality is equal to a conventional automatic, but slip, fluid drag and lydraulic losses in the system result in only slightly improved efficiency and acceleration over the conventional planetary automatic. Developing the control strategy is costly too."Recent advances in conventional automatic technology have weakened the argument to develop and set up production for CVT or DCT." says Bill Martin, managing director of transmission firm zeroshift. "Some carmakers have cancelled DCT projects because of the cost."The cheapest way to build an automatic is with an AMT. AMTs use actuators to replace the clutch pedal and gear stick of a conventional manual. They keep the high efficiency and acceleration of a manual gearbox, but the shift quality on some models is lacking. Torque interruptions and the head-nod effect are the most common complaint.so what is the alternative? There are always new ideas in transmissions, but Zeroshift says that its technology has efficiency benefits over a manual, delivering fuel economy improvements to city driving. Shift quality can also be equal to that of a refined automatic.Zeroshift's approach is an upgrade to the AMT. The synchromesh is replaced with an advanced dog enqaqement system.Dog engagement has been used for many years in motor sport to allow fast shifts. Conventional dog boxes are unsuitable for road use as the large spaces between the drive lugs or "dogs" create backlash, an uncomfortable shunt caused by the sudden change in torque direction.Zeroshift's technology solves this problem by adding a second set of drive dogs. It has also made each of the two sets of dogs only capable of transmitting torque in one or other opposing directions. "By controlling the engagement and disengagement of the two sets you can shift into the new gear befor disengaging the previous gear, "says Martin. "The shift quality is smoother than a typical modern six-speed automatic luxury car."The shift is instant and the torque is not interrupted.This philosophy is used for both up and down shifts."In conventional AMT there is an emissions spike during a shift due to the need to back off and reintroduce throttle, this is eliminated by going seamless, "says Martin. "This also reduces fuel consumption."It is a relative newcomer to the transmission sector, but the firm says that it is already attracting the attention of major European and US carmakers. The big draw is as a low-cost alternative to DCT, says Martin.Because the manual gearbox architecture is largely maintained, production costs and complexity are not greater than for a conventional AMT. Development of the controlsside is also considerably cheaper. Music to the ears of engineers trying to cut emissions and costs."Most of the carmakers have seen the system at least once," says Martion. "Some signed us immediately. Some have said not yet. None have said no. "That may be the clearest sign yet that when it comes to powertrain developments, carmakers are starting to focus on the transmission.HOW ZWROSHIFT WORKSThe hardware consists of two sets of bullets. mounted and actuated on two independent bullet rings. both sets of bullets run on the common hub, which is attached to the shaft with splines.Each bullet has a special profile. On one side they have an angled face for engagement. These are diagonally opposed, allowing the bullet to have a drive function for one gear and an overrun function for the other gear. The engagement faces taper backwards slightly to ensure the bullet latches onto the engaged gear under load.the opposite corners have a ramp, which pushes the bullet out of the previous gear once the new gear has been engaged.In neutral both bullet rings are positioned midway between the ratios. To select first gear, the bullets are moved into mesh with the engagement dogs.The bullets are actuated via shift forks conected to the shift actuators.The driving bullets lock first gear to the output shaft and transfer torque from the gearwheel onto the output shaft. The first gear overrun bullets are also moved into gear to lock the wheel to the output shaft in the opposite direction. This transfrs torque from the gearwheel onto the output shaft when the throttle closes and the engine overruns. This eliminates the backlash you'd expect from a dog engagement gearbox.To shift up with an open throttle, first gear's overrun bullets are unloaded and move in to engage second gear. This is followed by the previous driving ring which becomes unloaded when second gear is taken up.If the bullet is stopped from engaging fully-dog-face to dog-face-the second gear wheel opens an engagement window due to the relative speed difference. With the bullet pushed against the engagement dog compliance between the fork and actuator allows the stored energyto fire the bullet into the window.The first gear overrun bullets have now become the second gear drive bullets. As second gear takes over, the load is removed from the first gear drive bullets. These bullets are now no longer held by their retention angie and can be either moved out of gear by actuators or pushed out of gear by contact with the ramp face of the bullet.The first gear drive bullets then move across into engagement with second gear. In second gear, the roles of the bullets are reversed.Audi RoadjetAudi plans to add comfort, luxury and practicality without increasing emissionsThe Roadjet concept, first shown at Detroit in January 2006,indicates a number of technical directions that Audi going to take in the coming year. The firm is focusing on interior design, powertrain, chassis, electronics and safety innovations.These new directions will help Audi strengthen its position in the sub-luxury market that it previously had to itself. Audi has two main tactics to attract new customers in the US. It is breaking into the sports utility vehicle(SUV)and compact utility vehicle(CUV)markets.It also introduces new luxury and lifestyle features to strengthen its position in the US; sales there still lag behind those of BMW, Lexus and Mercedes-Benz. The recently launched Q7 off-road luxury vehicle is a late bid to capitalise on the SUV boom.In Europe, the carmaker's technical innovations such as aluminium construction, four-wheel-drive, and novel powertrain technologies have been successful. But if Audi wants to increase its US market share, it needs to innovate in those areas valued by American customers: comfort, luxury and practicality.Audi's designers have focused on this in the interior. They have devised a new wrap-around instrument panel shape to replace the more functional design in existing models. They have expanded the vehicle's multi-media interface (MMI)control system, used for cruise control, suspension, climate and entertainment separate controls. Combined with an upgraded climate system, occupants can set their own individual climate settings.Soft, warm, earthy colours are used in the Roadjet to create a feeling of well-being. The concept uses high quality functional materials: the upholstery is fine leather; the floor is neoprene. The space between the rear seats can house a range of optional equipment: the show car featured an espresso coffee machine. Storage boxes and baby carriers are more realistic alternatives.To enhance practicality, the rear seats slide backwards and forwards diagonally to increase shoulder and leg-room or rear load space. When the rear seats are in their most forward position, an oblique-facing child seat can be used behind the seats.Roadjet's load bay features an eletrically extending load floor to ease loading, offering unmerous lashing points to secure luggage items. The sliding seats and extending load floor are very likely to enter production on Audi's Q5 and A4 models.To heighten the sense of luxury, the concept uses a costly 1,000W Bang & Olufsen sound system with 14-speakers.This incorporates a "digital voice support" function that uses microphones and the car's speakers to pick up and amplify passengers' voices to ensure clear conversation even at high speeds.In a bid to improve road safety, convenience and traffic management, carmakers are working to common standards to develop a new in-car system to talk to other cars and roadside wireless olcal area networks. In traffic jams, bad weather or accident situations, cars send information to emergency services, other cars and traffic computers. The Roadjet concept featres previews such a system.The weight of all the new electronics and luxury equipment in this segment, combined with customers' growing demand for power is having a negative effect onexhaust emissions and fuel consumption. Audi is looking at sophisticated technical solutions to balance the equation.Roadjet's 3.2-litre gasoline direct injection engine is based on an existing engine but features a new fixed intake manifold with an integral vacuum reservoir to increase its output. This is combined with a two-stage cam operated variable valve lit technology to increase output.Despite the sports car performance, the Roadjet's overall fuel consumption is slightly lower than the current A4 Quattro 3.2FSI.The valve train technology, due to enter production later in 2006,lets the engine perform economically and smoothly during normal driving, switching automatically to more responsive, more powerful characteristics when the driver demands.Roadjet also has the first Audi application of speeddependent variable ratio dynamic steering for a stable highspeed motorway ride but with enhanced control on twisty country roads. Electronically-controlled variable rate dampers automatically adjust from soft and comfortable to firm and sporty to enhance safety and handling.Audi's engineers have electronically linked all of these systems to create three driver-selectable programmes: dynamic, comfort and sport. Each programme adjusts the dampers, steering, gearbox and engine eletronics to give different driving experiences.Roadjet's body styling marks a new direction for the carmaker.At 1.55m high with a wheelbase 4.7m long and 2.85m wide, the concept is roomy. The firm has used a combination of sharp feature lines and careully-sculpted concave-section doors to disguise the height. While the trademark LED tail lights are likely to enter production unchanged, steerable xenon gas discharge lights will replace the LEDs in the headlamps.Around the end of 2007 Audi will launch the Q5 CUV, based on the next A4 platform. Smaller and lighter than the Q7,it will be well placed to compete in the profitable CUV segment in the US. The Roadjet previews elements of the interior and exterior styling of this model.The Q5 will need to be more rugged to match the outdoor lifestyle image of the CUVsegment. At the same time, for the European market, the Roadjet's sharp style previews the next A4 model range, which may produce a new hatchback body in 2007 to join the conventional saloon and Avant estate. The dashboard and other new interior refinements are likely to spread across the rest of the Audi range over the next 24 months.变速器变速箱通常不得不在舒适性和效率之间做出选择，但一种新型的“犬牙啮合式”变速箱可以同时改善这两种性能。
起重机专业英语词汇
起重机专业英语词汇1. 起重机（Crane）2. 桥式起重机（Overhead Crane）3. 门式起重机（Gantry Crane）4. 塔式起重机（Tower Crane）5. 行车（Hoist）6. 吊钩（Hook）7. 钢丝绳（Wire Rope）8. 滑轮（Pulley）9. 制动器（Brake）10. 电动机（Motor）11. 限位器（Limit Switch）12. 变频器（Inverter）13. 载荷（Load）14. 起升高度（Lifting Height）15. 工作半径（Working Radius）16. 起重量（Lifting Capacity）17. 最大起升速度（Maximum Lifting Speed）18. 运行速度（Running Speed）19. 安全装置（Safety Device）20. 驾驶室（Cab）21. 操作手柄（Control Lever）22. 控制系统（Control System）23. 液压系统（Hydraulic System）24. 电气系统（Electrical System）25. 轨道（Rail）26. 支腿（Outrigger）27. 防摇摆装置（AntiSway Device）28. 定滑轮（Fixed Pulley）29. 动滑轮（Moveable Pulley）30. 钢丝绳夹（Wire Rope Clamp）掌握这些专业英语词汇，有助于在起重机行业中进行顺畅的沟通与交流，提高工作效率。
在今后的工作中，不断积累和丰富自己的专业英语词汇，将为您的职业生涯增添更多亮点。
起重机专业英语词汇扩展31. 起重机操作员（Crane Operator）32. 起重机维护工程师（Crane Maintenance Engineer）33. 起重机设计工程师（Crane Design Engineer）34. 起重机安全规程（Crane Safety Regulations）35. 起重机载荷表（Crane Load Chart）36. 起重机检验（Crane Inspection）37. 起重机租赁服务（Crane Rental Service）38. 起重机安装（Crane Installation）39. 起重机拆卸（Crane Dismantling）40. 起重机故障排除（Crane Troubleshooting）41. 起重机配件（Crane Spare Parts）42. 起重机制造商（Crane Manufacturer）43. 起重机经销商（Crane Dealer）44. 起重机售后服务（Crane AfterSales Service）45. 起重机操作培训（Crane Operation Training）46. 起重机认证（Crane Certification）47. 起重机保险（Crane Insurance）48. 起重机载荷测试（Crane Load Test）49. 起重机远程控制（Crane Remote Control）50. 起重机节能技术（Crane EnergySaving Technology）了解这些词汇，不仅有助于您在起重机行业中的专业交流，还能让您在阅读相关英文资料、参加国际会议或与外国同行沟通时更加得心应手。
汽车式起重机液压系统外文文献翻译中英文
外文文献翻译(含：英文原文及中文译文)文献出处：K Tanizumi. Truck Crane Hydraulic System: Technical Status and Development Trend [J]. Advanced Materials Research, 2015, 310-319中文译文汽车式起重机液压系统: 技术现状与发展趋势K Tanizumi1行业背景1.1工程汽车起重机的发展趋势近20年世界工程起重机行业发生了很大变化。
RT(越野轮胎起重机) 和AT(全地面起重机) 产品的迅速发展,打破了原有产品与市场格局,在经济发展及市场激烈竞争冲击下, 导致世界市场进一步趋向一体化。
为与RT 和AT 产品抗衡, 汽车起重机新技术、新产品也在不断发展。
近年来汽车起重机在英、美等国市场的复兴,使人们对汽车起重机产生新的认识。
几年前某些工业界人士曾预测, RT 和AT 产品的兴起将导致汽车起重机的衰退。
日本汽车起重机在世界各地日益流行,以及最近格鲁夫、特雷克斯、林克.贝尔特、德马泰克等公司汽车起重机的产品进展, 已向上述观念提出挑战。
随着工程起重机各机种间技术的相互渗透与竞争,汽车起重机会在世界市场中继续占有一席之地。
国外工程起重机从整体情况分析, 领先国内10~20年(不同类型产品有所不同) 。
随着国外经济发展速度趋于平稳,工程起重机向智能、高性能、灵活、适应性强、多功能方向发展。
25t 以下基本上不生产,产品向高附加值、大吨位发展, 住友建机、多田野和加藤公司曾于1989年相继推出360t 汽车起重机。
住友建机在90年代开发出80t ~250t 共4种AT 产品。
多田野也在90年代相继推出100t ~550t 共6种特大型AT 产品。
加藤公司则研制成NK5000型500t 汽车起重机。
行业配套也与国内有所不同:(1)下车主要是300kW 以上柴油大功率发动机,与之配套的液力变矩器和自动换档变速箱、12吨级驱动转向桥及越野轮胎。
汽车起重机主要部件中英文对照
汽车起重机主要部件中英对照随着越来越多的外资品牌起重机进入中国市场，汽车起重机行业的竞争也越来越激烈，用户的选择和需要接触的信息也越来越多。
用户在面对一款外国起重机产品手册时，往往束手无策。
本文将向大家介绍汽车起重机产品和各项性能的对照英文翻译，让你在面对英文版产品手册时也不再发愁。
汽车起重机整体结构（）中英文对照①副臂Boom with extension②起重臂伸缩机构Boom telescopic③主臂Main boom④变幅机构Luffing⑤起升机构Hoist⑥卷扬马达Hoist motor⑦支腿机构Outrigger⑧回转机构Slewing⑨底盘Chassis⑩液压系统Hydraulics⑪驾驶室Driver Cab一、汽车起重机外形尺寸（Mobile Crane Dimensions）中英文对照接近角Approach angle 30离去角Departure angle 10.5最小离地间隙260（320）轴距Wheel Base 3950高度Height 3080长度Length 8440汽车地盘长度Chassis Length 7002基础臂长Base boom length 68001-支腿纵向跨距Outrigger Longitudinal span2-2-支腿横向跨距Outrigger Transverse span 3-3、4-机身宽度WidthCrane Weights 起重机总重量Gross vehicle weight (GVW) 车辆总重量(GVW)Axle Loads 桥负荷Steering axle (axle 1) 转向桥(桥1)Drive axle (axle 2) 驱动桥(桥2)Ground Clearances 通过性参数Minimum ground clearance 最小离地间隙Ramp angle 纵向通过角Approach angle 接近角Departure angle 离去角Wheel Base 轴距Distance between axle 1 and 2 桥1 和2 之间的距离Wheel Track 轮距Axle 1 桥1Axle 2 桥2Outrigger Dimensions 支腿跨距Longitudinal span 纵向跨距Transverse span 横向跨距Outrigger Forces 支腿反力Maximum counterforce 最大支反力Overall Dimensions 外形尺寸(Length x Width x Height) (长x 宽x 高)技术描述Lifting Capacity 起重量Maximum rated capacity for main hook主钩额定起重量Maximum load moment最大起重力矩Boom and Components 主臂和零件Profile截面形状Number of sections节数Base boom length基本臂长度Base boom maximum lift height基本臂最大起升高度Base boom maximum working radius基本臂最大作业半径Fully extended boom length全伸臂长度Fully extended boom maximum lift height全伸臂最大起升高度Fully extended boom maximum working radius全伸臂最大作业半径Jib 副臂Jib length副臂长度Slewing speed回转速度Winch Performance 起升机构工作速度Main hoist – 3rd layer – single rope speed主卷扬- 第三层- 单绳速度Crane Boom Function Speeds 起重臂工作速度Elevation – up起臂Elevation – down落臂Full extension全伸Full retract全缩Outrigger Function Speeds 支腿工作速度Simultaneous full extension同步伸出Simultaneous full retract同步收缩Outrigger Controls 支腿操纵Dual outrigger controls – LH and RH side支腿操纵- 左侧和右侧Ambient working temperature作业温度Engine and Transmission 发动机和变速箱Engine发动机Emission compliance排放标准Number of cylinders缸数Aspiration进气Rated power额定功率Maximum torque最大扭矩Estimated fuel consumption per 100 km100 km 油耗Fuel type燃油类型Fuel tank capacity燃油箱容积Manual gearbox手动变速箱Hydraulics 液压装置Combined system with dual pump带有双泵的组合系统Hydraulic controls:液压控制：Mechanical, multi-lever controls机械式，多杆控制底盘基本构造1-发动机Engine2-离合器Cluth3-变速箱Transmission Case4-万向节Universal Flange5-后桥壳Rear Axle Housing6-差速器Differential7-半轴Axle Shaft8-后桥Rear Axle9-中桥Intermediate Axle10-主减速器Reducer11-传动轴Drive ShaftEngineChassis and Components 底盘及其部件Axle drive system桥驱动系统Minimum turning radius最小转弯半径Maximum gradeability最大爬坡度Maximum traveling speed最高行驶速度Driver Cab 驾驶室Dong Feng truck cab东风卡车驾驶室Adjustable driver seat调式司机座椅可Fitted with heater加热器Operator Cab 操纵室Adjustable seat可调式座椅Ergonomically placed switches and gauges开关和仪表的布置符合人机工程学Recirculation fan循环风扇主要参数表最大起重量Max.Rated Lifting Capacity最大起升高度Max.Lifting Height主臂Main Boom副臂JibM最大起升力矩ax.Hoisting Moment最大起升速度(单绳) Max.Lifting Rope Speed 回转速度Slewing Speed外形尺寸Qutline Dimension整机重量Weight Data底盘号Chassis Model发动机型号Diesel Model发动机功率Max.Power of engline最大扭矩Max.Torque of engine最小转弯半径Min.Turing Radius最大爬坡度Max.Gradeabilitg最高行驶速度Max.Trave Ling Speed接近角Approach Angle离去角Angle of Departure支腿距离(纵向×横向) Qutriggers Di Stance。
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本科毕业设计（论文）外文翻译译文题目：使用智能液压缸增加起重机的稳定性学院：机电学院专业：机械设计制造及其自动化学生姓名：XXX学号：**********指导教师：XXX完成时间：2017年3月12日From：Hitchcox, Alan. Smart cylinders stabilize cranes[J]. Hydraulics & Pneumatics; Cleveland (Sep 12, 2013): n/a.Smart cylinders stabilize cranesHitchcox, Alan.ASM International, Penton Media, OTP Industrial Solutions(formerly Ohio Transmission & Pump Co)Abstract：It's not unusual for cranes to reach 100 ft or more into the air at major construction sites. Traditionally, cranes are transported to a work area and assembled on-site. More recently, as truck-mounted cranes become bigger and more powerful, they have found favor because they are quicker to set up than traditional cranes. Truck-mounted cranes have a telescoping hydraulic boom mounted on commercial truck chassis. Their portability and lower setup costs have led to their widespread use at construction and utility sites around the world. But as loads get heavier and lifting distances become higher, designers of truck-mounted cranes must provide the stability to ensure that safety remains the top priority.Truck-mounted cranes use outrigger systems to ensure stable operation. The outriggers extend from the main body of the truck and contact the ground several feet away from the truck. This distributes the crane's load over a much larger area, thereby increasing stability. Manitowoc Company Inc., Manitowoc, Wis., takes this a step further by using smart cylinders in the A-frame outrigger systems of its National Crane line of truck-mounted cranes. The crane's hydraulic system is driven from a power takeoff on the truck's transmission. The crane operator then runs all crane functions through a series of lever-operated valves at a control station.The ELA is an externally mounted LDT that uses Hall-effect technology to sense the location of a magnet embedded in the cylinder's piston through the cylinder's carbon steel barrel. A microprocessor then assigns an analog voltage to the magnet's corresponding absolute position. For example, when the cylinder is fully retracted; the voltage may be 0.55 V. As the cylinder extends, the voltage gradually increases until 4.5 V is reached at full extension.Accuracy of the transducer is typically +-0.5 mm (0.02 in.) - more than adequate for most mobile equipment. That position is then sent to the ECM and compared to the known maximum horizontal extension. After this, an indication is given to the operator about the outrigger state. The position update happens within milliseconds.Full TextIt's not unusual for cranes to reach 100 ft or more into the air at major construction sites. Traditionally, cranes are transported to a work area and assembled on-site. More recently, as truck-mounted cranes become bigger and more powerful, they have found favor because they are quicker to set up than traditional cranes. Truck-mounted cranes have a telescoping hydraulic boom mounted on commercial truck chassis. Their portability and lower setup costs have led to their widespread use at construction and utility sites around the world. But as loads get heavier and lifting distances become higher, designers of truck-mounted cranes must provide the stability to ensure that safety remains the top priority.Truck-mounted cranes use outrigger systems to ensure stable operation. The outriggers extend from the main body of the truck and contact the ground several feet away from the truck. This distributes the crane's load over a much larger area, thereby increasing stability. Manitowoc Company Inc., Manitowoc, Wis., takes this a step further by using smart cylinders in the A-frame outrigger systems of its National Crane line of truck-mounted cranes. The crane's hydraulic system is driven from a power takeoff on the truck's transmission. The crane operator then runs all crane functions through a series of lever-operated valves at a control station.An important function for lifting, moving, and lowering heavy loads is to ensure that outrigger beams are properly positioned. The outriggers are attached to the truck frame and are extended downward by hydraulic cylinders at an angle to create an A-frame structure that is wider at its base than at the top. This provides a stable framework to level and support the loaded and extended crane.Adding smarts to outriggersFor the past several years, National Crane has added outrigger-monitoring systems (OMSs) to its cranes. With the OMS, operators monitor the horizontal extension of the crane's outriggers at a control station. The OMS used with A-frame model cranes includes an ELAposition-sensing linear-displacement transducer (LDT) from Rota Engineering, Dallas, an electronic control module (ECM), and bicolor indication LEDs at each station.The ELA is an externally mounted LDT that uses Hall-effect technology to sense the location of a magnet embedded in the cylinder's piston through the cylinder's carbon steel barrel. A microprocessor then assigns an analog voltage to the magnet's corresponding absolute position. For example, when the cylinder is fully retracted; the voltage may be 0.55 V. As the cylinder extends, the voltage gradually increases until 4.5 V is reached at full extension. Accuracy of the transducer is typically +-0.5 mm (0.02 in.) - more than adequate for most mobile equipment. That position is then sent to the ECM and compared to the known maximum horizontal extension. After this, an indication is given to the operator about the outrigger state. The position update happens within milliseconds.Mark Hoffman, of Rota Engineering, pointed out that because mobile equipment has a human operator, position feedback from cylinders generally only needs to be within hundredths of an inch. Put simply, he says that magnetostrictive LDTs are overkill for most mobile-equipment applications. He suggests that an LDT with slightly less precision, but substantially lower cost, would enable designers to provide cylinder position feedback more often - not just for the most critical applications that justify high cost.Simple electronic displayThe electronic control module on the A-frame units serves only to monitor the position of the outriggers and provide feedback to the operator. As the analog voltage from the ELA transducer is read into the ECM, it sends a signal to a set of bicolor LEDs - one set per operator's station. The indications available are:Red for system error (sensor out of range, electrical short, etc.).Blinking red to indicate the operator is not at a valid working position as directed by the operation manual.Green to inform the operator that full horizontal extension has been accomplished. The ECM can be configured through the use of a service tool to also help diagnose any issues related to the OMS.Made for mobileDesigned for use with mobile equipment, the ELA transducer matches this application well because of several physical and intrinsic attributes. The most important of these is theability to mount the sensor along the exterior of the hydraulic outrigger-cylinder barrel. Although the cylinder gains added functionality, in many cases it retains the same form and fit as the original cylinder; the smart cylinder is essentially a drop-in replacement. The envelope in which the cylinder is mounted does not change. Only additional harnessing and the ECM are added - plus there are minor physical changes to the rear stabilizers.The cylinder bores used in A-frame outriggers range from 3 to 4.5 in. Strokes may be as long as of 66.9 in., depending on lifting capacity. According to Hoffman added, "Eliminating the expense of gun-drilling the piston rod and machining the end cap reduces the cost of creating this smart cylinder. The cylinder's structural integrity remains the same, and it is easier to assemble, install, and service than cylinders with magnetostrictive sensors."Other positive attributes: the Hall-effect sensor is noncontact for long service life, its temperature rating is high, it performs well in high shock and vibration applications, and its aluminum housing resists damage from impact and corrosion. The external transducer can be replaced in the field without difficulty.Cylinders can be supplied with magnets already fitted, so that if the stroke-sensing function is required later, the transducer can easily be added. The magnet assembly for the EL transducer is designed to match the bore of the cylinder. A slot is milled into the piston to accommodate the magnet assembly. Service life is not a factor because the magnet assembly is made of the same quality as piston-wear rings.A different kind of linear sensorModel ELA linear-displacement transducers (LDTs) use Hall-effect technology and mount externally to mobile hydraulic cylinders. Unlike other types of in-cylinder LDTs, they can be used in double-ended cylinders. They can also be used effectively in steering and long-stroke cylinders, where gun drilling can become cost prohibitive and are easily field replaceable.Hall-effect LDTs can be manufactured for strokes exceeding 50 ft and for use 20,000 ft below the surface of the ocean and other demanding environments.Hall-effect technologyLDTs from Rota Engineering use a microprocessor that transmits and receives signals from Hall-effect chips mounted to a printed-circuit board. The circuit board is contained within a stainless-steel or aluminum housing, depending on application requirements. Apiston-mounted magnet causes a voltage drop when it passes over the Hall-effect chip. The microprocessor calculates the position of the Hall-effect chip and correlates the voltage drop to a proportional voltage, current, PWM, or CANbus output.Hoffman explains, "Hall-effect sensors do not have as high a resolution as magnetostrictive sensors, which can achieve resolution measured in ten-thousandths of an inch. Hall-effect LDTs, however, generally have resolution of 0.012 to 0.020 in. The tighter resolution of magnetostrictive LDTs is needed for many process applications, such as a rolling mill. Most of the time, though, 0.020-in. resolution is more than sufficient for mobile hydraulic applications."An additional benefit of the Hall-effect technology is small size. In most instances, the pin-to-pin dimension of a cylinder need not be increased to accommodate a Hall-effect LDT. Also, the surface-mount technology tolerates high levels of vibration, and potting can provide additional vibration resistance.For more information, contact Rota Engineering at (972) 359-1041, or visit . For information on Manitowoc's truck-mounted cranes and other products, visit www.manitowoc.译自：希契科克斯，艾伦. 使用智能液压缸增加起重机的稳定性[J]. 液压与气动技术；克利夫兰（2013年9月12日）：n/a使用智能液压缸增加起重机的稳定性希契科克斯，艾伦ASM国际片通媒体,OTP工业解决方案(以前俄亥俄州传输和泵有限公司)摘要:在大型的建筑工地上起重机将重物举至空中100英尺及以上的情况并不罕见。