机械设计外文翻译中英文

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机械设计外文文献翻译、中英文翻译

外文原文Mechanical DesignAbstract:A machine is a combination of mechanisms and other components which transforms, transmits. Examples are engines, turbines, vehicles, hoists, printing presses, washing machines, and movie cameras. Many of the principles and methods of design that apply to machines also apply to manufactured articles that are not true machines. The term "mechanical design" is used in a broader sense than "machine design" to include their design. the motion and structural aspects and the provisions for retention and enclosure are considerations in mechanical design. Applications occur in the field of mechanical engineering, and in other engineering fields as well, all of which require mechanical devices, such as switches, cams, valves, vessels, and mixers.Keywords: Mechanical Design mechanisms Design ProcessThe Design ProcessDesigning starts with a need real.Existing apparatus may need improvements in durability, efficiency, weight, speed, or cost. New apparatus may be needed to perform a function previouslydone by men, such as computation, assembly, or servicing. With the objective wholly or partlyIn the design preliminary stage, should allow to design the personnel fully to display the creativity, not each kind of restraint. Even if has had many impractical ideas, also can in the design early time, namely in front of the plan blueprint is corrected. Only then, only then does not send to stops up the innovation the mentality. Usually, must propose several sets of design proposals, then perform the comparison. Has the possibility very much in the plan which finally designated, has used certain not in plan some ideas which accepts.When the general shape and a few dimensions of the several components becomeapparent, analysis can begin in earnest. The analysis will have as its objective satisfactory or superior performance, plus safety and durability with minimum weight, and a competitive cost. Optimum proportions and dimensions will be sought for each critically loaded section, together with a balance between the strengths of the several components. Materials and their treatment will be chosen. These important objectives can be attained only by analysis based upon the principles of mechanics, such as those of static for reaction forces and for the optimum utilization of friction; of dynamics for inertia, acceleration, and energy; of elasticity and strength of materials for stress and deflection; of physical behavior of materials; and of fluid mechanics for lubrication and hydrodynamic drives. The analyses may be made by the same engineer who conceived the arrangement of mechanisms, or, in a large company, they may be made by a separate analysis division or research group. Design is a reiterative and cooperative process, whether done formally or informally, and the analyst can contribute to phases other than his own. Product design requires much research and development. Many Concepts of an idea must be studied, tried, and then either used or discarded. Although the content of each engineering problem is unique, the designers follow the similar process to solve the problems. Product liability suits designers and forced in material selection, using the best program. In the process of material, the most common problems for five (a) don't understand or not use about the latest application materials to the best information, (b) failed to foresee and consider the reasonable use material may (such as possible, designers should further forecast and consider due to improper use products. In recent years, many products liability in litigation, the use of products and hurt the plaintiff accused manufacturer, and won the decision), (c) of the materials used all or some of the data, data, especially when the uncertainty long-term performance data is so, (d) quality control method is not suitable and unproven, (e) by some completely incompetent persons choose materials.Through to the above five questions analysis, may obtain these questions is does not have the sufficient reason existence the conclusion. May for avoid these questions to these questions research analyses the appearance indicating the direction. Although uses the best choice of material method not to be able to avoid having the product responsibility lawsuit, designs the personnel and the industry carries on the choice of material according to the suitable procedure, may greatly reduce the lawsuit the quantity.May see from the above discussion, the choice material people should to the material nature, the characteristic and the processing method have comprehensive and the basic understanding.Finally, a design based upon function, and a prototype may be built. If its tests are satisfactory, the initial design will undergo certain modifications that enable it to be manufactured in quantity at a lower cost. During subsequent years of manufacture and service, the design is likely to undergo changes as new ideas are conceived or as further analyses based upon tests and experience indicate alterations. Sales appeal.Some Rules for DesignIn this section it is suggested that, applied with a creative attitude, analyses can lead to important improvements and to the conception and perfection of alternate, perhaps more functional, economical,and durable products.To stimulate creative thought, the following rules are suggested for the designer and analyst. The first six rules are particularly applicable for the analyst.1. A creative use of need of physical properties and control process.2. Recognize functional loads and their significance.3. Anticipate unintentional loads.4. Devise more favorable loading conditions.5. Provide for favorable stress distribution and stiffness with minimum weight.6. Use basic equations to proportion and optimize dimensions.7. Choose materials for a combination of properties.8. Select carefully, stock and integral components.9. Modify a functional design to fit the manufacturing process and reduce cost.10. Provide for accurate location and noninterference of parts in assembly.Machinery design covers the following contents.1. Provides an introduction to the design process , problem formulation ,safety factors.2. Reviews the material properties and static and dynamic loading analysis ,Including beam , vibration and impact loading.3. Reviews the fundamentals of stress and defection analysis.4. Introduces fatigue-failure theory with the emphasis on stress-life approaches to high-cycle fatigue design, which is commonly used in the design of rotation machinery.5. Discusses thoroughly the phenomena of wear mechanisms, surface contact stresses ,and surface fatigue.6. Investigates shaft design using the fatigue-analysis techniques.7. Discusses fluid-film and rolling-element bearing theory and application8. Gives a thorough introduction to the kinematics, design and stress analysis of spurgears , and a simple introduction to helical ,bevel ,and worm gearing.9. Discusses spring design including compression ,extension and torsion springs.10. Deals with screws and fasteners including power screw and preload fasteners.11. Introduces the design and specification of disk and drum clutches and brakes. Machine DesignThe complete design of a machine is a complex process. The machine design is a creative work. Project engineer not only must have the creativity in the work, but also must in aspect and so on mechanical drawing, kinematics, engineerig material, materials mechanics and machine manufacture technology has the deep elementary knowledge. One of the first steps in the design of any product is to select the material from which each part is to be made. Numerous materials are available to today's designers. The function of the product, its appearance, the cost of the material, and the cost of fabrication are important in making a selection. A careful evaluation of the properties of a. material must be made prior to any calculations.Careful calculations are necessary to ensure the validity of a design. In case of any part failures, it is desirable to know what was done in originally designing the defective components. The checking of calculations (and drawing dimensions) is of utmost importance. The misplacement of one decimal point can ruin an otherwise acceptable project. All aspects of design work should be checked and rechecked.The computer is a tool helpful to mechanical designers to lighten tedious calculations, and provide extended analysis of available data. Interactive systems, based on computer capabilities, have made possible the concepts of computer aided design (CAD) and computer-aided manufacturing (CAM).How does the psychologist frequently discuss causes the machine which the people adapts them to operate. Designs personnel''s basic responsibility is diligently causes the machine to adapt the people. This certainly is not an easy work, because certainly does not have to all people to say in fact all is the most superior operating area and the operating process.Another important question, project engineer must be able to carry on the exchange and the consultation with other concerned personnel. In the initial stage, designs the personnel to have to carry on the exchange and the consultation on the preliminary design with the administrative personnel, and is approved. This generally is through the oral discussion, the schematic diagram and the writing material carries on.If front sues, the machine design goal is the production can meet the human need the product. The invention, the discovery and technical knowledge itself certainly notnecessarily can bring the advantage to the humanity, only has when they are applied can produce on the product the benefit. Thus, should realize to carries on before the design in a specific product, must first determine whether the people do need this kind of product Must regard as the machine design is the machine design personnel carries on using creative ability the product design, the system analysis and a formulation product manufacture technology good opportunity. Grasps the project elementary knowledge to have to memorize some data and the formula is more important than. The merely service data and the formula is insufficient to the completely decision which makes in a good design needs. On the other hand, should be earnest precisely carries on all operations. For example, even if places wrong a decimal point position, also can cause the correct design to turn wrongly.A good design personnel should dare to propose the new idea, moreover is willing to undertake the certain risk, when the new method is not suitable, use original method. Therefore, designs the personnel to have to have to have the patience, because spends the time and the endeavor certainly cannot guarantee brings successfully. A brand-new design, the request screen abandons obsoletely many, knows very well the method for the people. Because many person of conservativeness, does this certainly is not an easy matter. A mechanical designer should unceasingly explore the improvement existing product the method, should earnestly choose originally, the process confirmation principle of design in this process, with has not unified it after the confirmation new idea.外文资料翻译译文机械设计摘要：机器是由机械装置和其它组件组成的。

机械设计过程外文文献翻译、中英文翻译

附录英文Machine design processThe machine is the organization with other components combinations, transforms，the transmission or using the energ，the strength or the movementexample for the beneficial use has the engine．the turbine wheel，the vehicles．the hoist，the printer，the washer and the movie camera Many is suitable tbr themachine design principle and the strength law also is suitable to is not thegenuine machine finished product．the driven wheel hub and the file cabinet tothe measuring appl iance and the nuclear pressure vessel．”Machine designt thisterminology compared to”machine design”more generalized，it including machine design．But regarding certain instruments．1ike uses to determine hot，the mobile line and the volume thermal energy as well as the fluid aspect question needs alone to consider．But when machine design must consider themovement and the structure aspect question as well as preserved and the sealstipulation．In the mechanical engineering domain and all that project domainapplication machine design，all need such as mechanism and so on the svdtch,cam，valve，vessel and mixer．The design beginning tO being true or the imagination need．The existing instrument possibly needs in the durability，the efficiency，the weight，the speedor the cost performs to improve．]he possible need new instrument tO completebefore made the function by the person．1ike t was abundant Assembly or maintenance．After the goal completely or partially determines，the design nextstep is the idea carl complete needs the ffmction the organization and its thearrangement for this，the free hand drawing schematic diagram value is enormous，it not only takes a person idea the recording and the auxiliary．methodwhich if the other people discusses，moreover especially is suitable for with ownidea exchange，also needs to concern as the creative mentality stimulant to thepart widespread knowledge，because a new machine frequently by knew very well each kind of components rearrange or the replace become，perhaps changedthe size and the material．Regardless of after idea process or，a designer callcarry on fast either the sketchy computation or the analysis determines thegeneral size and the feasibility．After about need or may use the spatial meteidea determination，may start according to the proportion picture schematicdiagram．When several components approximate shapes and several sizes come out，the analysis was allowed truly to start．The analysis goal lies in enable it to havesatisfying or the superior performance，as well as will seek the best proportionand the size under the smallest weight security and the durability and thecompetitive cost designer for each essential load bearing section，as well asseveral components intensities balance then choice material and processingmethod．These important goals only have through only then may obtain based on the mechanism analysis，like about reacting force and friction most superioruse principie of statics；About inertia，acceleration and energy principle ofdynamics：About stress and deflection material elasticity and intensity principle；About material physical behavior principle；About lubrication and water poweractuation hydromechanics principle．The analysis may identical engineer whicharranges by the idea machinery do，or makes the analysis in the big company bythe independent analysis department or the research group the result，possibleneed new arrangement and new size．No matter is officially does orunofficialdoes，supposes Japan is relapse and the cooperation process．the analysis staffmay play the role to all stages but not merely is he stage.Some design criteriaIn this part，some people suggested carries on the analysis using the creative manner，this kind of analysis may cause the significant improvement aswell as to the spare product idea and the consummation，the product functionmore．more economical，is perhaps more durable． The creation stage does notneed is at first and the independent stage．Alttlough the analysis staff possiblycertainlv is not responsible for the entire design，but he not meyely is can fromthe numeral proposc wants question correct answer which he soIVes，not merelyis Droduces the stress value，the size or the work limit. He may propose a morewidespread opinion，in order to improvement standard or plan. Because beforethe analysis or in the analysis process，he can familiar install and its the workingcondition．he is in an idea to prepare chooses the plan the rantage Poinl．Best hecan propose the suggestion transfigure eliminates the moment of force or thestress concentration，but was not the permission constructs has the blgsectlonand the excessively many dynamic loads organization should better be he discards his careful desi{；n but is not afterwards saw the machinery discarded.In order to stimulate the creative thought，below suggested designs thepersonnel and the analysis staff uses the criterion.The first 6 criteria especially are suitable for the analysis staff,although he possibly involves to possesses this l o items.1．Creatively the use needs the physical performance and the control doesnot need．2．Knows the practical load and its the importance.3．D00s not consider the function load in advance.4．Invents the more advantageous loading environment.5．Provides the minimurn weight the most advantageous stress distributionand the rigidity．6．uses the fundamental equation computation proportion and causes thesize optimization．7．The selection material obtains the perlbrmance combination．8．In between spare parts and integrated components carefid choice． 9．Revisions functional design adapts the production process and reduces thecost．10．In the consideration assembly causes the part pintpointing and mutuallydoes not disturb．Designs the personnel to have in such domain，like the statics，the inematics，dynamics and the materials mechanics have the good accomplishment，in addition．but also must familiar make the material and themanufacture craft．Designs the personnel to have to be able to combine allcollrelations the fact，carries on teaches Wei．the manufacture schematic diagramand the charting comes the manufacture request totransmit the workshop． Any product design one of first step of work is the choice uses in to makeeach part the material．Today design personnel may obtain innumerably．When choice，the product function，the outward appearance，the material cost and theproduction cost very are all important．Before any computation must carefullyappraise the material the performance．It is the necessary careful computation toguarantee the design the validity The computation ever does not appear on thechart，but is saved by ten each kind of reason．Once any part expires，had makeclear when is designing at first this had the flaw the components has made any；Moreover，。

机械专业毕业设计外文翻译12

Development of a high-performance laser-guided deep-holeboring tool: optimal determination of reference origin for precise guidingAbstractA laser-guided deep-hole boring tool using piezoelectric actuators was developed to prevent hole deviation. To extend the depth o controll able boring further, the following were improved. The tool’s guiding error, caused by misalignment of the corner cube prism and the mirror in the optical head from the spindle axis, was eliminated using an adjustment jig that determined the reference origins of the two position-sensitive detectors (PSDs) precisely. A single-edge counter-boring head is used instead of the double-edge head used up to now The former was thought to be better in attitude control than the latter. A new boring bar, which was lower in rigidity and better in Controllability of tool attitude, was used. Experiments were conducted to examine the performance of the new tool in detail and to determin its practical application, using duralumin (A2017-T4) workpieces with a prebored 108-mm diameter hole. The experiments were performed with a rotating tool–stationary workpiece system. Rotational speed was 270 rpm and feed was 0.125 mm/rev. Tool diameter was 110 mm Asaresult,controlled boring becomes possible up to a depth of 700 mm under the stated experimental conditions.700 mm is the maximum machinable length of the machine tool. The tool can be put to practical use.Keywords: Deep hole-boring; Adaptive control; Laser application1.IntroductionTo bore a precise straight hole, a deep-hole boring tool should be guided toward a target. From this point of view, the laser-guided deep-hole boring tool was developed [1–6]. The latest tool using piezoelectric actuators could be guided to go straight toward the target,despitedisturbances up to a depth of 388 mm [6].In the present paper, before the performance of the tool is examined, the following points are improved to extend the depth. The tool’s guiding error, caused by misalignment of the corner cube prism and the mirror in the optical head from the spindle axis, is eliminated using a jig that deter- mines the reference origins of the two position-sensitive detectors (PSDs) precisely. A single-edge counter-boring head is used instead of the double-edge head used up to now. The former is thought to be better in attitude control than the latter. A new boring bar, which is 15% lower in both bending and torsional rigidity and which is better in controllability of tool attitude, is used.2. Experimental apparatusFigs. 1 and 2 show the tool head and the experimental apparatus, respectively [6]. The head is the same as that used in experiments up to now. One cutting edge of the double-edge counter-boring head is replaced by a guide pad,And six guide pads are removed[4].By removal of the guide pads, cutting oil is supplied better between the other guide pads and hole wall. The tool head consists of an optical head, a counter-boring head, piezoelectric actuators, and an actuator holder (Fig. 1). The optical head is attached to the front surface of the counter-boring head through an adjust- ment jig. The actuator holder is connected to a rotation stopper 14 behind the tool head by two parallel plates of phosphor bronze 6 (Fig. 2). A laser source 11, and PSDs 9, 10 are set in front of the tool. The rectangular coordinates XAnd Y are set on a plane perpendicular to the spindle rotation axis(Z-axis).The optical distancebetween a dichroic mirror in the optical head and PSD 10 for measuring tool inclina- tion is 2,040 mm [2].3. Method for detection of tool position and its inclinationFig. 3 shows the method used for measuring the tool position and its inclination. The laser beam, radiated from an argon laser, reaches the dichroic mirror 6 through the beam expander 5 and the half mirror 1. The dichroic mirror separates the two beams of wavelengths 514 nm (green) and 488 nm (blue). The green beam for measuring tool position passes through the dichroic mirror 6 and reachesthe corner cube prism 8. The reflected beam passes again through 6 and is deflected by the half mirror 1 toward dichroic mirror 2. By passing through the dichroic mirror 2, it reaches the PSD 9 used for measuring tool position. The blue beam for measuring tool inclination reaches the dichroic mirror 7 with an angle of incidence equal to 0°. The dichroic mirror 7 reflects the blue beam and trans- mits parts of the green beam, which are not completelyseparated by the dichroic mirror 6. The returning beam from the dichroic mirror 7 is deflected by the mirrors 6, 1, and 2, then passing through the dichroic mirror 4, and reaches the PSD 10 for measuring tool inclination. Re- flective characteristics of dichroic mirror 4 differs from that of dichroic mirror 7.4. Acquisition of data for controlling the toolData for tool attitude control are acquired from the two PSDs for tool position and its inclination every rotation of the counter-boring head. Until now, outputs of the two PSDs (measuring tool position and its inclination) some- times did not correspond well to the measured hole devia- tion. To determine what causes this, the following is exam- ined. The tool head with the optical head is supported by two V-blocks and is aligned on the Z-axis at the same longitudinal position as in the experiment. Then, the laser beam is radiated, and the optical head is rotated manually.Fig. 4 shows variations of outputs of two PSDs with encoder pulse during one rotation of the optical head fixed on the counter-boring head. Theoretically, outputs of two PSDs are constant during one rotation of the optical head corresponding to a 1,400 pulse of output of an encoder. Changes of X- and Y-outputs of tool position are caused by change of darkness of the laser spot because of interference and polarization of the laser beam. Changes of X- and Y- outputs of tool inclination are caused by inclination of the reflecting mirror in the optical head from the Z-axis. From the last experiment [6] on, tool position and its inclination are measured at rotational pulse position 700, where the brightness of the two PSDs are preferable at the same time.5. Misalignment of the optical parts in the optical headEven if the laser source and the PSDs for tool position and its inclination are aligned on Z-axis, hole deviation appeared. To discover its cause, the misalignment of the corner cube prism and inclination of reflecting mirror in the optical head from the Z-axis are examined.Fig. 5 shows all cases of alignment errors. Fig. 5(a) shows that the corner cube prism and the reflecting mirror are precisely aligned on the Z-axis. Figs. 5(b) and 5(c) are, the cases in which the corner cube prism is displaced by and the reflecting mirror is inclined byfrom the Z-axis, respectively.IncaseofFig.5(d),errorsofFigs.5(b)and(c) occur together. Fig. 5(e) shows the case when the optical head is inclined byduring the setup of the counter-boring head. Fig. 5(f) is the worst case, when all errors occur together. These errors cannot be eliminated by conventional adjustment. Therefore a new guiding strategy is developed to ensure that the tool can be guided straight, even if errors should occur.6. Optimal setup of reference origin for precise guidingFig. 6 shows the optimal setup method of reference origins. The laser source is aligned on the Z-axis [Fig. 6(a)] [6]. The optical head is fixed to the front surface of a cylindrical alignment jig through an adjustment jig. The alignment jig is inserted into the guide bush, which is fixed on a machine table, and the centers of both alignment jig and the optical head are aligned on Z-axis. Then the laser beam is radiated. Reflected beams reach the PSDs for tool position and its inclination. When the cylinder is rotated by hand, the rotational position, at which the output is most reliable, can be found. Next, the PSDs are moved until the spots lie at their centers. This position corresponds to the pulse position 700 of the encoder. The centers are reference origins for tool position and its inclination.At this rotational position,the optical head is fixed to the counter-boring head using the adjustment jig [Fig.6(b)].When the control starts, the tool head follows the alignment jig’s axis.7. Mechanism of tool displacementFig. 7 shows the mechanism of tool displacement. Fig. 7(a) shows the normal cutting condition [7]. The cutting force P is acting on the cutting edge and is counterbalanced by the guide pads. Fig. 7(b) shows the case where the tool is to correct for a deviation. A chain double-dashed line shows the hole wall before correction of hole deviation. A Directed line shows the direction of the correction.When the tool is controlled to incline toward the direction of the directed line, a cutting edge set ahead of the guide pads overcuts the hole wall. When the guide pad on the opposite side comes to the position of the overcutting zone, the cutting edge leaves a noncutting zone on the hole wall Opposite the overcutting zone.As a result,tool shifts toward the direction of the directed line.In the case of double-edge counter-boring head, the cut- ting force acting on one cutting edge is balanced by the force that acts on the other cutting edge [7]. As a result, the head is easy to vibrate, and the mechanism of tool displace- ment does not function well.Form: Precision Engineering 24 (2000) 9–14 开发高性能的激光制导deep-holeboring工具：最佳测定参考来源精确指导摘要激光制导深孔钻具使用压电致动器是防止孔偏差。

机械设计专业外文文献翻译

机械设计专业外文文献翻译general。

however。

materials that are easy to machine have high machinability。

while those that are difficult to machine have low XXX。

microstructure。

and mechanical properties。

as well as the XXX。

material。

and wear resistance.XXX factors。

cutting speed。

feed rate。

and depth of cut also play XXX the amount of heat generated in the cutting zone and decreasing the time that the cutting tool is in contact with the XXX。

at high cutting speeds。

tool wear and cutting forces can increase。

which can ce tool life and surface finish quality.Feed rate and depth of cut also XXX the amount of material that is removed and the forces that are generated during cutting。

Higher feed rates and deeper cuts can improve material removal rates。

but they can also increase cutting forces and heat n。

which can ce tool life and surface finish quality.Overall。

机械设计外文翻译

机械设计外文翻译Mechanical DesignMechanical design is a branch of engineering that deals with the creation and development of machines and mechanical systems. It involves the application of principles and methodologies from various disciplines such as physics, materials science, and mathematics to design machines that are safe, reliable, and efficient.Mechanical design is a crucial aspect of engineering because it is responsible for creating machines that are used in a wide range of industries. From automobiles and airplanes toindustrial machinery and consumer products, mechanical design plays a vital role in the development of these machines. It requires a deep understanding of the principles of mechanics, thermodynamics, and materials science, as well as a creative and problem-solving mindset.In addition to designing machines, mechanical design also involves considerations of cost, safety, and environmental impact. Engineers must balance the performance and functionality of a machine with its cost and the impact it may have on the environment. They must also ensure that the machine is safe to use and meets all relevant regulations and standards. This often involves conducting risk assessments and performing stress andfailure analysis to identify potential issues and ensure the machine meets the required safety and quality standards.。

机械设计外文文献翻译、中英文翻译

机械设计外文文献翻译、中英文翻译unavailable。

The first step in the design process is to define the problem and XXX are defined。

the designer can begin toXXX evaluated。

and the best one is XXX。

XXX.Mechanical DesignA XXX machines include engines。

turbines。

vehicles。

hoists。

printing presses。

washing machines。

and XXX and methods of design that apply to XXXXXX。

cams。

valves。

vessels。

and mixers.Design ProcessThe design process begins with a real need。

Existing apparatus may require XXX。

efficiency。

weight。

speed。

or cost。

while new apparatus may be XXX。

To start。

the designer must define the problem and XXX。

ideas and concepts are generated。

evaluated。

and refined until the best one is XXX。

XXX.XXX。

assembly。

XXX.During the preliminary design stage。

it is important to allow design XXX if some ideas may seem impractical。

they can be corrected early on in the design process。

机械设计外文翻译英文原文1

Study on cascaded whole-leaf spring oscillation mechanism for mould in continuous castingL.-P.Zhang*1,X.-K.Li2,Y.-F.Yao2and L.-D.Yang3A design method of a cascaded whole-leaf spring mechanism is proposed,which is a new oscillation guidance device for the mould in continuous casting.Then its prototype designed in this paper is produced in the lab,of which kinematics and dynamics simulations are carried out based on the rigid–flexible coupling virtual model.Simulation curves of the displacement and velocity of the mould are almost consistent with the ideal ones,which verifies the model built in this paper is rational.Furthermore,natural frequencies and mode shapes of the mechanism are calculated by dynamics simulation,and forces applied on leaf springs and revolute joints are analysed and effects of the basic parameters on these forces are also studied,which establish the basis for further studies and next application of this mechanism.Keywords:Continuous casting,Mould,Cascaded whole-leaf spring oscillation mechanism,Design method,Dynamics analysisIntroductionThe oscillation system for the mould is the key equipment to the modern continuous casting technol-ogy,of which the technical performance and reliability directly affect the quality and production of continuous casting slabs.The oscillation system is composed of the oscillation generating device and guiding mechanism, and the latter is studied in this paper.During continuous casting,the oscillation guiding mechanism plays a guidance role in the motion of the mould.Only when the mould vibrates along the correct track,the quality of the strand can be ensured.So the strand requires very high guidance accuracy of the oscillation guiding mechanism for the mould.But for inevitable gap and wear of the bearings,the four-eccentric axes and four-bar linkage oscillation mechanisms widely used in modern casting will cause uncontrolled deviation in motions of the mould,which badly affects the quality of the strand.1Therefore,the semi-and whole-leaf spring mechanisms are gradually used as guidance mechanisms for the mould in billet and slab continuous casting.2,3In recent years,with further development of the semi-and whole-leaf spring oscilla-tion mechanisms,the cascaded whole-leaf spring oscilla-tion mechanism is developed abroad,4which has a longer life,higher lateral rigidity and reliability and so on.However,until now,reports on this oscillation mechanism are few.5,6Its working principle has been proposed by the authors,7based on which design method of the cascaded whole-leaf spring oscillation mechanism is proposed in this paper and its experi-mental prototype is manufactured.Furthermore,the rigid–ﬂexible coupling virtual model of the cascaded whole-leaf spring oscillation mechanism is built and its kinematics and dynamics simulations are analysed using many types of software,such as ANSYS.System modes and the forces applied on leaf springs and revolute joints of the mechanism are analysed,which establish the basis for further studies and application of this mechanism.Working principle of cascaded whole-leaf spring guidance mechanismThe structure of the cascaded whole-leaf spring oscilla-tion mechanism is shown in Fig.1.It mainly consists of the cascaded leaf spring,vibration table and frame, which can be driven by machinery(Fig.1a),or hydraulics servo(Fig.1b),generating device of sinusoi-dal or non-sinusoidal oscillation.And the cascaded leaf spring is composed of four steel plate springs divided into two sets.All leaf springs’extension lines join to the circular arc centre of the continuous caster and their ends are separately connected to the vibration table and the frame,as shown in Fig.2,and then two sets of leaf springs,the vibration table and the frame form two four-bar linkage guidance devices.During the mould vibrat-ing,ﬂexible leaf springs produce elastic deformations, which make two leaf spring four-bar linkage guidance devices alternately play a guidance role in the mould without any interference by the generating device.71The Mechatronics and Information Engineering School,Foshan University,Foshan528000,China2College of Mechanical Engineering,Yanshan University,Qinhuangdao 066004,China3No.2Research Development Department,Xi’an Heavy Machinery Research Institute,Xi’an710032,China*Corresponding author,email zhanglpok@204ß2010Institute of Materials,Minerals and MiningPublished by Maney on behalf of the InstituteReceived14November2008;accepted16September2009DOI10.1179/030192309X12573371383677Ironmaking and Steelmaking2010VOL37NO3Design of cascaded whole-leaf spring oscillation mechanismFrom working principle of the cascaded whole-leaf spring oscillation mechanism,it can be seen that two leaf spring four-bar linkages carry on the guidance to the mould.If design is unreasonable,the motion of the two leaf spring four-bar linkages will interfere during vibration,which will block the mould.Therefore,how to design these two leaf spring four-bar linkages becomes the key problem.Design method of cascaded whole-leaf spring oscillation mechanismAccording to the characters of the cascaded whole-leaf spring mechanism developed from the short-arm four-bar linkage,its design method is proposed as following:(i)based on the design principles of the short-armfour-bar linkage simulating arc,8design two rigid four-bar linkages under the same basic para-meters of the mould by optimum design,which fulfil the requirement for guiding accuracy of the mould simulating arc(ii)for settling interference of the two four-barlinkages,rigid linkages optimised in step (i)are substituted by steel plate springs with elastic deformation and then form two leaf spring four-bar linkages(iii)based on the basic principles of the short-armfour-bar linkage,arrange two leaf spring four-bar linkages according to Fig.2.That is,end-points A 1,C 1and A 2,C 2are fixed on the frame;endpoints B 1,D 1and B 2,D 2are connected to the vibration table of the mould.In this way,two leaf spring four-bar linkages are cascaded,so a cascaded whole-leaf spring mechanism is designed.Calculation exampleCalculations of parameters and guidance accuracy of rigid four-bar linkagesAccording to the geometry relations and the movement relationships of the four-bar linkage guidance devices of the arc caster (see Fig.2),the position of any point on the mould can be calculated during the mould vibration.In this paper,taken the bottom point E on the outer arc of the mould as an example,formulas of the track and the guiding accuracy of point E are deduced,as listed in Table 1,with only one rigid four-bar linkage guiding for the mould.To calculate conveniently,it is assumed that l 1,l 2,l 3and l 4are respectively the lengths of linkages of A 1C 1,A 1B 1,B 1D 1and C 1D 1,and A 2C 2,A 2B 2,B 2D 2and C 2D 2;S is the amplitude of the mould;D Q is the swing angle of the linkage of B 1D 1and B 2D 2under the max displace-ment of the mould downward;R is the caster’s basic radius;R 1and R 2are radius respectively from the arc centre to two endpoints of linkages A 1C 1,B 1D 1,A 2C 2and B 2D 2;H 1and H 2are the heights of both sides to the horizontal centerline of the mould;a is the included angle between OE and the horizontal centreline of the arc caster when the mould is at equilibrium position;h 1,h 2,r 1and r 2are respectively the included angles between linkages of A 1C 1,A 2C 2,B 1D 1,B 2D 2and the horizontal centreline of the caster;D R E is the simulated arc error of the mould.Mathematical model and optimisation of linkagesOscillation parameters of the mould and the installation positions of linkages are the primary designing terms of the guidance mechanism.Taking arc caster for example,outside penalty function optimisation method is adopted in optimum design of the two rigid four-bar linkages.In four-bar linkages design,it is the goal that the trajectory error of the mould meets the requirement for guiding accuracy.So the objective function of the optimisation mathematical model can be written by f(x )~D R E ~OE ’{R ¡0:02(1)According to Table 1,it can be seen that the design optimisation variables are x ~R ,S ,h ,r ,R 1,R 2½ T(2)By experience,geometric dimensions and installation positions of two four-bar linkages must meet the followingconstraints2Layout of cascaded whole-leafspringa mechanic driven;b hydraulics servodriven1Cascaded whole-leaf spring oscillation mechanismZhang et al.Cascaded whole-leaf spring oscillation mechanism for mould in continuous castingIronmaking and Steelmaking 2010VOL37NO320530D ¡R ¡50D 2¡S j j ¡10R 1w 0,h w 0R 2w R 1,r w h 0:91R ¡R 2v R 0:82R ¡R 1¡0:91R(3)where D is the thickness of billet;h and r are included angles between linkages and horizontal centreline of the caster.Based on the objective function (equation (1)),optimisation variables (equation (2))and constraints established in equation (3),optimisation procedure of outside penalty function is compiled by C language and two four-bar linkages are separately optimum designed.Optimisation resultsIn optimisation,it is assumed that the mould is arranged symmetrically about its equilibrium position and its height H 1z H 25900mm;the thickness of the billet D 5150mm;the guiding accuracies of two rigid four-bar linkages D R E 50?02mm.Therefore,the geometrical parameters and the guiding accuracies of the two rigid four-bar linkages are optimum designed (Table 2).By the optimised results,rigid linkages are substituted by leaf springs arranged according to Fig.2;then a cascaded whole-leaf spring mechanism is designed.Experimental prototype of cascaded whole-leaf spring oscillation mechanismBased on the optimised results,the experimental proto-type of the cascaded whole-leaf spring oscillation mechan-ism for the mould is manufactured,as shown in Fig.3,in which leaf spring four-bar linkage A 1C 1B 1D 1is composed of leaf springs 1and 4;and leaf spring four-bar linkage A 2C 2B 2D 2is made up of leaf springs 2and 3.Leaf spring four-bar linkages A 1C 1B 1D 1and A 2C 2B 2D 2are located at both sides of the mould in the vertical direction of casting.And parameters of the prototype are rounded numbers of Table 2and guidance accuracy is calculated after round-ing,as listed in Table 3.Flexible multibody theoryVectors of location,velocity and acceleration of point on flexible bodyBased on the small deformation theory,complicated motion of the ﬂexible body can be decomposed to severalTable 2Optimised results of two rigid four-bar linkagesFour-bar linkage A 1B 1C 1D 1Four-bar linkage A 2B 2C 2D 2R ,mm 5974.695902.74S,mm ¡3.33¡3.19h ,rad 0.050.08r ,rad 0.170.14R 1,mm 5219.795233.23R 2,mm 5490.995505.41D R ,mm20.020.0193Experimental prototypeTable 1Formulas of parameters of two rigid four-bar linkages and error of bottom point E on mould Four-bar linkage A 1B 1C 1D 1Four-bar linkage A 2B 2C 2D 2l 15l 35R 22R 1l 15l 35R 22R 1a 5arcsin(H 2/R )a 5arcsin(H 2/R )D Q 52arcsin(S /2l 1cos r 1)D Q 52arcsin(S /2l 1cos r 1)l 252R 1sin[(r 12h 1)/2]l 252R 1sin[(r 12h 1)/2]l 452R 1sin[(r 12h 1)/2]l 452R 1sin[(r 22h 2)/2]D 1E ~½R 22z R 2{2R 2R cos (r 1{a ) 1=2D 2E ~½R 21z R 2{2R 1R cos (r 2{a ) 1=2C 1E ~½R 22z R 2{2R 2R cos (h 1{a ) 1=2C 2E ~½R 21z R 2{2R 1R cos (h 2{a ) 1=2A 1D 1’~f l 21z l 22z 2l 1l 2sin ½(r 1{h 1)=2z D Q g 1=2A 2D 2’~f l 21z l 22{2l 1l 2sin ½(r 2{h 2)=2{D Q g 1=2c ~arccos ½(l 24z D 1E 2{C 1E 2) (2l 4:D 1E )c ~arccos ½(l 24z D 2E 2{C 2E 2) (2l 4:D 2E )v ~arccos ½(l 24z AD 1’2{l 23).(2l 4:AD 1’) v ~arccos ½(l 24z AD 2’2{l 23).(2l 4:AD 2’)b ~arccos ½(l 21z AD 1’2{l 22).(2l 1:AD 1’)b ~arccos ½(l 21z AD 2’2{l 22).(2l 1:AD 2’)OD 1’~½R 21z l 21z 2R 1l 1cos D Q 1=2OD 2’~½R 22z l 21{2R 2l 1cos D Q 1=2w ~arccos ½(OD 1’2z l 21{R 21).(2OD 1’:l 1)w ~arccos ½(OD 2’2z l 21{R 22).(2OD 2’:l 1)d 5w z c z v z bd 5w z c 2(v z b )OE ’~½D 1E 2z OD 1’2{2D 1E :OD 1’:cos d 1=2OE ’~½D 2E 2z OD ’22{2D 2E :OD 2’:cos d 1=2D R E 5OE 92R D R E 5OE 92RTable 3Parameters of prototypeLeaf spring four-bar linkage A 1B 1C 1D 1Leaf spring four-bar linkage A 2B 2C 2D 2R ,mm 6000.006000.00S ,mm ¡3.00¡3.00h ,u 3.005.00r ,u 10.008.00R 1,mm 5220.005235.00R 2,mm 5490.005505.00D R ,mm20.0160.018Zhang et al.Cascaded whole-leaf spring oscillation mechanism for mould in continuous casting206Ironmaking and Steelmaking 2010VOL37NO3simple motions.So the location vector of any point on the ﬂexible body can be expressed as equation (4).9r p ~r 0z A (s P z u P )(4)where A is the matrix of direction cosine;r P is the vector of point P in the inertial coordinate system;r 0is the vector of the origin of moving coordinate in the inertial coordinate system;s P is the vector of point P in moving coordinate system when the ﬂexible body is undeformed;and u P is the relative deﬂection of point P expressed by modal coordinates namely u P 5W P q (where W P is the assumed modal matrix and q is the generalised coordinate of deformation).Differentiating equation (4)with respect to time,vectors of velocity and acceleration are calculated:r p ~:r 0z :A (s P z u P )z A W P :q::r p ~::r 0z ::A (s P z u P )z 2:A W P :q z A W P ::q(5)Flexible multibody dynamic equationConsidering the location,direction and mode of point P on the ﬂexible body,the generalised coordinate is selected,as in equation (6).j ~x y z y h w q i (i ~1,:::,M )½ T ~r y q ½ T(6)The motion equation of ﬂexible body is deduced from d L L: {L L z l L y T {Q ~0y ~08><>:(7)where y is restraint equation;l is Lagrange multiplier corresponding to restraint equation;Q is generalised force projected to generalised coordinate j ;L is Lagrange item with L 5T 2W ,and T and W respectively denote kinetic energy and potential energy.The kinetic energy of ﬂexible body is calculated by T ~12:j T M (j ):j(8)where M (j )is mass matrix and M (j )~M tt M tr M tm M T tr M rrM rm M T tm M Trm M mm2435;subscripts t ,r and m respectively denote translation,revolution and modal freedom.The potential energy of ﬂexible body includes the gravitational potential energy and the elastic potential energy,that isW ~W g (j )z 12j T K j(9)where K is generalised stiffness matrix corresponding to modal coordinates and is a constant.Because the mass of the ﬂexible leaf springs is very small comparing to other parts of the oscillation mechanism with cascaded whole-leaf spring,its potential energy could be ignored.So substituting equations (8)and (9)into equation (7),differential equation of motion of the ﬂexible body is written as follows M ::j z :M :j {12L M L j :j T :j z K j z l L y L jjT~Q (10)Kinematics simulation of cascadedwhole-leaf spring oscillation mechanismBased on the ﬂexible multibody theory,the virtual design and then kinematics simulation of the experi-mental prototype of the cascaded whole-leaf spring oscillation mechanism for the mould with non-sinusoi-dal oscillation are carried out using many types of softwares,such as ANSYS,10,11and curves of displace-ment and velocity of the mould are obtained and compared with the ideal ones.Simulation modelBased on the structural characteristic of the cascaded whole-leaf spring oscillation mechanism,it is assumed as follows:(i)the vibration table is symmetric about x –y planeand direction of –y is the casting direction,with the coordinate as shown in Fig.4(ii)leaf springs with elastic deformation are regardedas flexible bodies.Eccentric shaft,connecting rod,vibration table and frame with big stiffness are taken for rigid bodies.So the simulation model of the experimental prototype is built,in which leaf springs 1and 4are composed of two groups of leaf spring four-bar linkage A 1C 1B 1D 1;and leaf springs 2and 3are formed by two groups of leaf spring four-bar linkage A 2C 2B 2D 2(Fig.4).Kinematics simulation and resultsTo simulate the actual non-sinusoidal motion law of themould with the guidance of the cascaded whole-leaf spring mechanism,a non-uniform rotational speed is imposed on the eccentric shaft,as shown in Fig.4,in which the frequency f 52Hz,the deﬂection ratio of oscillation a 530%and the amplitude of the mould h 53mm.The displacement and velocity curves of the vibration table (i.e.movement curves of the mould)are shown in Fig.5,of which the errors compared with the ideal curves are shown in Fig.6.From Fig.5,it can be seen the virtual vibration table can move along the given non-sinusoidal rule.Although the oscillation waveform of the mould in simulation has error compared with the ideal curves (Fig.6),the maximum errors of the displacement and the velocity are very small (0?0068mm and 0?1287mm s 21respec-tively),and can be ignored.Therefore,it is concluded that the virtual model is rational and can be usedfor4Simulating modelZhang et al.Cascaded whole-leaf spring oscillation mechanism for mould in continuous castingIronmaking and Steelmaking 2010VOL37NO3207further study on the cascaded whole-leaf spring mechanism.Dynamics simulation of oscillation mechanismBased on the dynamic simulation of the cascaded whole-leaf spring oscillation mechanism,system modal and the forces applied on leaf springs and revolute joints are analysed.Modal analysis of oscillation mechanismUsing the instantaneous freezing method of mechan-ism,12modal analysis of the cascaded whole-leaf springguidance mechanism is carried out,from which system modals and natural frequencies are obtained.For the frequency of non-sinusoidal oscillation in continuous casting is not very high,13natural frequencies and mode shapes from the ﬁrst to the ﬁfth are emphasised in this paper with related information of the modals listed in Table 4.Limited by space,only the ﬁrst to the third mode shapes are shown in Fig.7.From modal analysis of the mechanism above,it is known that the ﬁrst and the second natural frequencies are lower and resonance may occur on the mould in continuous casting.14When resonance occurs,the mould will deﬂect from the correct trajectory,which badly impacts on the quality of strand.So it must be ensured that the working frequency in continuous casting is far from the ﬁrst and the second natural frequencies of the cascaded whole-leaf spring oscillation mechanism.Analysis of forces applied on leaf springsOwing to the symmetry about the x –y plane,leaf springs in both sides of the cascade whole-leaf spring oscillation mechanism have the same forces and deformations,only the one at the positive axis of z is analysed.For the cascade whole-leaf spring mechanism,leaf spring four-bar linkage A 1C 1B 1D 1and A 2C 2B 2D 2alternately play the guidance role on the mould and forces applied on the leaf spring and their deformations are very complicated.So it is difﬁcult to analyse leaf springs well only by experiments and computer simulation has important signiﬁcance.In this paper,based on the virtual proto-type technology,dynamics simulation is carried out,by which forces curves of leaf springs are obtained during the mould movement.Furthermore,effects of basic oscillation parameters on these forces are analysed,which establish the basis for further study on the reliability of themechanism.5a displacement and b velocity curves of vibrationtableTable 4Natural frequencies and modes shapes from ﬁrst to ﬁfth order Modality order Natural frequency,Hz Mode shapes172058Vertical vibration of the vibration table along the casting direction (–y )211.4723Deviated swing of the vibration table about the axis of x 323.7038Vibration of leaf spring 1423.7068524.0872Transverse vibration of the vibration table along the z axis z vibration of leaf spring17a ﬁrst and b second modal mode shapes of systemZhang et al.Cascaded whole-leaf spring oscillation mechanism for mould in continuous casting208Ironmaking and Steelmaking 2010VOL37NO3Forces applied on leaf springs at different amplitudesTo understand the forces applied on leaf springs under different amplitudes,the motion of the mould with different lengths of the eccentric shaft respectively h 53mm and h 52mm (that is the amplitudes of the mould)are taken for example to simulate in which the deﬂection ratio of oscillation and the frequency are the same to those in the section on ‘Kinematics simulation and results’.Forces applied along the length direction of leaf springs,for example,are analysed in this paper.Based on the dynamic simulations,forces applied on the ends of leaf springs 1,4and 2,3in a period are obtained as shown in Fig.8.It can be seen that the forces applied on the ends of leaf springs 1and 4are similar and vary at non-sinusoidal rules.When the mould works above its equilibrium position at the ﬁrst half-period,two leaf springs are compressed on the action of negative forces;when the mould moves under side of its equilibrium position at the second half-period,these two leaf springs are tensioned with positive forces.Furthermore,the values of forces are directly proportional to the distance of the mould departing from its equilibrium position.When the mould moves to its max.displacement,both leaf springs will bear the largest forces.And forces applied on the leaf springs get bigger as the amplitude of mould increases.Forces applied on leaf springs 2and 3vary with the same law,yet opposite to those of leafsprings 1and 4.When the mould is above its equilibrium position at the ﬁrst half-period,leaf springs 2and 3bear tensile forces;however,at the other half-period,both leaf springs bear pressure.Similarly the values of forces are proportional to the distance of the mould off its equilibrium position and the forces get bigger as the amplitudes of the mould increase.Forces applied on leaf springs at different deflection ratio of oscillationWith the same frequency and amplitude in the section on ‘Kinematics simulation and results’,based on the dynamic simulations at different deﬂection ratios of oscillation a 1510%,a 2530%,a 3550%,force curves of each leaf spring are obtained,as shown in Fig.9.From Fig.9,it can be seen that with the same frequency and amplitude of oscillation,deﬂection ratios of the force curves of leaf springs become bigger as the deﬂection ratio of oscillation enlarges,but the amplitudes of forces applied on every leaf spring keep constant.At the same time there are forces applied in the normal direction of the length of leaf spring,which vary with the same rule to the forces along the length direction.In general,forces applied on leaf springs periodically vary with the same periodicity to the system’s during the mould vibration,the values of which are proportional to the distance of the mould departing from its equilibrium position and get bigger as the amplitude of the mould increases.Deﬂection ratiosofa leaf spring 1;b leaf spring 4;c leaf spring 2;d leaf spring 38Forces applied on leaf springs at differentamplitudesa leaf spring 1;b leaf spring 2;c leaf spring 3;d leaf spring 49Forces applied on leaf springs at different deﬂection ratioZhang et al.Cascaded whole-leaf spring oscillation mechanism for mould in continuous castingIronmaking and Steelmaking 2010VOL37NO3209the force curves of leaf springs become bigger with the deﬂection ratio of oscillation enlarging,but the ampli-tudes of forces of every leaf spring are invariant. Effect of basic oscillatory parameters on joint forcesThe basic oscillatory parameters are often adjusted to meet different technologies in continuous casting,which will affect the joint forces of kinematic pairs and then the dynamic characteristic of the mechanism.Therefore, joint forces are analysed of the cascade whole-leaf spring oscillation mechanism,which shows that amplitude and deﬂection ratio of oscillation affect joint forces with the similar law to forces applied on leaf springs.Joint forces get bigger as the amplitude of the mould increases and deﬂection ratios of joint force curves become bigger with increasing the deﬂection ratio of oscillation;however, the amplitudes of joint forces are constant.Based on analyses above,the cascaded whole-leaf oscillation mechanism can be properly designed for the mould in continuous casting according to practical conditions,which can make the mould vibrate along the correct track with better performance and higher reliability of production.Therefore,the theory basis for application is established.Conclusions1.A design method of the cascaded whole-leaf spring oscillation mechanism is proposed at first.Then a cascaded whole-leaf spring mechanism is designed using the method and its experimental prototype is produced.2.Rigid–flexible coupling full scale model of the prototype of the cascaded whole-leaf spring oscillation mechanism is established;furthermore,its kinematic and dynamic simulations are analysed and compared to those of ideal curves,the results of which verify that the virtual model is rational.3.Working frequency of the system in continuous casting must be kept away from its first and second natural frequencies to avoid resonance.4.The amplitudes of forces applied on leaf springs and revolute joints are only determined by the amplitude of the mould and enlarge with the amplitudes of the mould increasing;and as the deflection ratio of oscillation increases,the deflection of force curves becomes greater.OutlookSuch a system is now being planned for use in industry. References1.Y.G.Yan and X.J.Wang:‘Error analysis and comparison of twotypical mold oscillators’,Heavy Mach.,2006,3,46–48,54.2.in‘800problems of steel-making-continuous casting technology’,214–216;2004,Beijing,Metallurgical Industry Press.3.E.S.Szekeres:‘Overview of mold oscillation in continuouscasting’,Iron Steel Eng.,1996,7,29–37.4.F.Wimmer:‘High speed billet casting:theoretical investigationsand practical experience’,Proc.VAI CCC’96,Linz,Austria,May 1996,VAI,Paper1.TE:‘The cascaded whole-leaf springs oscillation device’,Chinese patent no.ZL02238393.x,February2003.6.R.Ko¨hl,K.Mo¨rwald,J.Po¨ppl and H.Tho¨ne:‘The DYNAFLEXoscillator–a technology breakthrough in billet casting’,Iron Steel, 2001,36,(8),22–25,29.7.L.P.Zhang,X.K.Li,Q.J.Zou and Y.F.Yao:‘Research of theseries whole-leaf spring oscillation mechanism’,Mach.Design Res.Suppl.,2008,24,79–81.8.Z.X.Lei and D.K.Xu:‘Optimum design and analysis of four-barlinkage oscillation mechanism of arc continuous caster’,J.Univ.Iron Steel Beijing,1982,3,80–89.9.Y.Lu:‘Dynamics of flexible multi-body system’,109–165;1996,Beijing,Advanced education Press.10.B.O.Al-Bedoor and A.A.Almusallam:‘Dynamics of flexible-jointmanipulator carrying a payload with rotary inertia’,Mech.Mach.Theory,2000,35,785–820.11.B.O.Al-Bedoor and Y. A.Khulief:‘Finite element dynamicmodeling of a translating and rotating flexible link’,Comput.Methods Appl.Mech.Eng.,1996,131,173–189.12.X.Tang and D.Jin:‘Dynamics of machinery’,169–170;1984,Beijing,Advanced education Press.13.X.K.Li and D.M.Zhang:‘Technology of the mold oscillation incontinuous casting’,20–25;2000,Beijing,Metallurgical Industry Press.14.R.Shao:‘Dynamics of mechanical system’,30–34;2005,Beijing,Mechanical Industry Press.Zhang et al.Cascaded whole-leaf spring oscillation mechanism for mould in continuous casting 210Ironmaking and Steelmaking2010VOL37NO3。

机械专业毕业设计外文翻译1

本科毕业设计（本科毕业论文）外文文献及译文文献、资料题目：High-rise Tower Crane designed文献、资料来源：期刊（著作、网络等）文献、资料发表（出版）日期：2000.3.25院（部）：机电工程学院专业：机电工程及自动化High-rise Tower Crane designed under Turbulent Winds At present, construction of tower cranes is an important transport operations lifting equipment, tower crane accident the people's livelihood, major hazards, and is currently a large number of tower crane drivers although there are job permits, due to the lack of means to monitor and review the actual work of a serious violation . Strengthen the inspection and assessment is very important. Tower crane tipping the cause of the accident can be divided into two aspects: on the one hand, as a result of the management of tower cranes in place, illegal operation, illegal overloading inclined cable-stayed suspended widespread phenomenon; Second, because of the tower crane safety can not be found in time For example,Took place in the tower crane foundation tilt, micro-cracks appear critical weld, bolts loosening the case of failure to make timely inspection, maintenance, resulting in the continued use of tower cranes in the process of further deterioration of the potential defect, eventually leading to the tower crane tipping. The current limit of tower crane and the black box and can not be found to connect slewing tower and high-strength bolts loosening tightened after the phenomenon is not timely, not tower verticality of the axis line of the lateral-line real-time measurement, do not have to fight the anti-rotation vehicles, lifting bodies plummeted Meng Fang, hook hoists inclined cable is a timely reminder and record of the function, the wind can not be contained in the state of suspended operation to prevent tipping on the necessary tips on site there is a general phenomenon of the overloaded overturning of the whole security risks can not be accurately given a reminder and so on, all of which the lease on the tower crane, use, management problems,Through the use of tower crane anti-tipping monitor to be resolved. Tower crane anti-tipping Monitor is a new high-tech security monitoring equipment, and its principle for the use of machine vision technology and image processing technology to achieve the measurement of the tilt tower, tower crane on the work of state or non-working state of a variety of reasons angle of the tower caused by the critical state to achieve the alarm, prompt drivers to stop illegal operation, a computer chip at the same time on the work of the state of tower crane be recorded. Tower crane at least 1 day overload condition occurs, a maximum number of days to reach 23 overloading, the driver to operate the process of playing the anti-car, stop hanging urgency, such as cable-stayed suspended oblique phenomenon often, after verification and education, to avoid the possible occurrence of fatal accidents. Wind conditions in the anti-tipping is particularly important, tower cranes sometimes connected with the pin hole and pin do not meet design requirements, to connect high-strength bolts are not loose in time after the tightening of the phenomenon, through timely maintenance in time after the tightening of the phenomenon, through timely maintenance and remedial measures to ensure that the safe and reliable construction progress. Reduced lateral line tower vertical axis measuring the number of degrees,Observation tower angle driver to go to work and organize the data once a month to ensure that the lateral body axis vertical line to meet the requirements, do not have to every time and professionals must be completed by Theodolite tower vertical axismeasuring the lateral line, simplified the management link. Data logging function to ensure that responsibility for the accident that the scientific nature to improve the management of data records for the tower crane tower crane life prediction and diagnosis of steel structures intact state data provides a basis for scientific management and proactive prevention of possible accidents, the most important thing is, if the joint use of the black box can be easily and realistically meet the current provisions of the country's related industries. Tower crane safety management at the scene of great importance occurred in the construction process should be to repair damaged steel, usually have to do a good job in the steel tower crane maintenance work and found that damage to steel structures, we must rule out potential causes of accidents, to ensure safety in production carried out smoothly. Tower crane in the building construction has become essential to the construction of mechanical equipment, tower crane at the construction site in the management of safety in production is extremely important. A long time, people in the maintenance of tower crane, only to drive attention to the conservation and electrical equipment at the expense of inspection and repair of steel structures, to bring all kinds of construction accidents.Conclusion: The tower crane anti-tipping trial monitor to eliminate potential causes of accidents to provide accurate and timely information, the tower crane to ensure the smooth development of the leasing business, the decision is correct, and should further strengthen and standardize the use of the environment (including new staff training and development of data processing system, etc.).The first construction cranes were probably invented by the Ancient Greeks and were powered by men or beasts of burden, such as donkeys. These cranes were used for the 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, harbour 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 utilised 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, and the largest floating cranes, 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.The 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 the classical 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 favour 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 labour, making the crane more preferable to the Greek polis than the more labour-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.During 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 of the 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.In 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.[25] This curious absence is explained by the high friction force exercised by medieval treadwheels which normally prevented the wheel from accelerating beyond control.目前，塔式起重机是建筑工程进行起重运输作业的重要设备，塔机事故关系国计民生、危害重大，而目前众多的塔机司机虽然有上岗证，由于缺少监督和复核手段，实际工作中违规严重。

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.机械设计理论机械设计是一门通过设计新产品或者改进老产品来满足人类需求的应用技术科形状和详细结构的基本主要研究产品的尺寸、学。

它涉及工程技术的各个领域，构思，还要研究产品在制造、销售和使用等方面的问题。

机械设进行各种机械设计工作的人员通常被称为设计人员或者机械设计工程师。

还必须在机械制设计工程师不仅在工作上要有创造性，计是一项创造性的工作。

材料力学和机械制造工艺学等方面具有深厚的基础知识。

工程材料、图、运动学、发现和科技机械设计的目的是生产能够满足人类需求的产品。

发明、如前所诉，知识本身并不一定能给人类带来好处，只有当它们被应用在产品上才能产生效必须先确定人们是否需因而，应该认识到在一个特定的产品进行设计之前，益。

要这种产品。

系统分析应当把机械设计看成是机械设计人员运用创造性的才能进行产品设计、掌握工程基础知识要比熟记一些数据和公和制定产品的制造工艺学的一个良机。

仅仅使用数据和公式是不足以在一个好的设计中做出所需的全部决式更为重要。

定的。

另一方面，应该认真精确的进行所有运算。

例如，即使将一个小数点的位置放错，也会使正确的设计变成错误的。

当新的方而且愿意承担一定的风险，一个好的设计人员应该勇于提出新的想法，所花费法不适用时，就使用原来的方法。

因此，设计人员必须要有耐心，因为为要求屏弃许多陈旧的，的时间和努力并不能保证带来成功。

一个全新的设计，一位机由于许多人墨守成规，这样做并不是一件容易的事。

人们所熟知的方法。

在此过程中应该认真选择原有械设计师应该不断地探索改进现有的产品的方法，的、经过验证的设计原理，将其与未经过验证的新观念结合起来。

只有当这些缺陷和问题被解决新设计本身会有许多缺陷和未能预料的问题发生，之后，才能体现出新产品的优越性。

因此，一个性能优越的产品诞生的同时，也就没如果设计本身不要求采用全新的方法，伴随着较高的风险。

应该强调的是，有必要仅仅为了变革的目的而采用新方法。

即使产不受各种约束。

应该允许设计人员充分发挥创造性，在设计的初始阶段，只有也会在设计的早期，生了许多不切实际的想法，即绘制图纸之前被改正掉。

这样，才不致于堵塞创新的思路。

通常，要提出几套设计方案，然后加以比较。

很有可能在最后选定的方案中，采用了某些未被接受的方案中的一些想法。

...设计人员的基本职责是努心理学家经常谈论如何使人们适应他们所操作的机器。

因为实际上并不存在着一个对力使机器来适应人们。

这并不是一项容易的工作，所有人来说都是最优的操作范围和操作过程。

在开始另一个重要问题，设计工程师必须能够同其他有关人员进行交流和磋商。

这一并得到批准。

阶段，设计人员必须就初步设计同管理人员进行交流和磋商，，需要解决般是通过口头讨论，草图和文字材料进行的。

为了进行有效的交流下列问题：）所设计的这个产品是否真正为人们所需要？（1 此产品与其他公司的现有同类产品相比有无竞争能力？2（）生产这种产品是否经济？（3）产品的维修是否方便？（4）5）产品有无销路？是否可以盈利？（产品的设计、制造和销售只能在只有时间能对上述问题给出正确答案。

但是，设计工程师还应该通过零件图和装配对上述问题的初步肯定答案的基础上进行。

图，与制造部门一起对最终设计方案进行磋商。

，在制造过程中会出现某个问题。

可能会要求对某个零件尺寸或公差作一通常工程上的更改必须要经过设计人员批准，些更改，使零件的生产变得容易。

但是，在产品的装配时或者装箱外运前的试验中才以保证不会损伤产品的功能。

有时，总是存在着发现设计中的某种缺陷。

这些事例恰好说明了设计是一个动态过程。

更好的方法来完成设计工作，设计人员应该不断努力，寻找这些更好的方法。

选择过程应该是一个对材料的工程材料的选择已经显得重要。

此外，近些年来，而一些原有的材料的能够获得的数新材料不断出现，连续不断的重新评价过程。

工人的健康及安全等方面经常会对材料的回收利用、量可能会减少。

环境污染、可能会要求使用不同材料选择附加新的限制条件。

为了减轻重量或者节约能源，对产品维修保养方便性要求的提高和顾客的反馈的材料。

来自国内和国际竞争、由于材料选用不当造成的产等方面的压力，都会促使人们对材料进行重新评价。

材料与材料加工之间的相互依赖关此外，品责任诉讼，已经产生了深刻的影响。

为了能在合理的成本和确保质量的前提下获系已经被人们认识得更清楚。

因此，确定和使用材设计工程师的制造工程师都必须认真仔细地选择、得满意的结果，料。

...）a制造任何产品的第一步工作都是设计。

设计通常可以分为几个明确的阶段：（）生产设计。

在初步设计阶段，设计者着重考虑cb）功能设计；（初步设计；（然后决定这种思想是否可行；通常要设想和考虑几个方案，产品应该具有的功能。

关于材料在此阶段，如果可行，则应该对其中一个或几个方案作进一步的改进。

如果没有的话，是否有性能符合要求的材料可供选择；选择唯一要考虑的问题是：是否有较大的把握在成本和时间都允许的限度内研制出一种新材料。

在这个阶段要绘制出在功能设计和工程设计阶段，要做出一个切实可行的设计。

通常要制造出样机或者实物模型，相当完整的图纸，选择并确定各种零件的材料。

并对其进行试验，评价产品的功能、可靠性、外观和维修保养性等。

虽然这种试验可能会表明，在产品进入到生产阶段之前，应该更换某些材料，但是，绝对不认真仔细地考虑能将这一点作为不认真选择材料的借口。

应该结合产品的功能，所选用成本和可靠性。

一个很有成就的公司在制造所有的样机时，产品的外观、这样对并尽可能使用同样的制造技术。

的材料应该和其生产中使用的材料相同，公司是很有好处的。

功能完备的样机如果不能根据预期的销售量经济地制造出则这种样机或者是样机与正式生产的装置在质量和可靠性方面有很大不同，来，选择和设计工程师最好能在这一阶段完全完成材料的分析、就没有多大的价值。

在生产设计阶段材料的更因为，确定工作，而不是将其留到生产设计阶段去做。

换是由其他人进行的，这些人对产品的所有功能的了解不如设计工程师。

使它们在生产设计阶段中，与材料有关的主要问题是应该把材料完全确定下来，而且材料的数量能够与现有的设备相适应，能够利用现有设备经济地进行加工，比较容易保证供应。

经验表明，不可避免地会出现对使用中的材料做一些更改的情况。

在制造过程中，在进行生产以后改换在大多数情况下，可采用某些便宜材料作为替代品。

然而，在设计阶段做好材料选择工材料要比在开始生产前改换材料所花费的代价要高。

在生产制造开始后出现了可供使用的新材料是更可以避免多数这样的情况。

作，换材料的最常见的原因。

当然，这些新材料可能降低成本、改进产品的性能。

但是，必须对新材料进行认真的评价，以确保其所有性能都满足要求。

应当记住，大部分的产品失效和新材料的性能和可靠性很少像现有材料那样为人们所了解。

没有真正了解它们的产品责任事故案件是由于在选用新材料作为替代材料之前，长期使用性能而引起的。

...在材料过产品的责任诉讼迫使设计人员和公司在选择材料时，采用最好的程序。

）不了解或者不会使用关于材料应用方面的最程中，五个最常见的问题为：（a未能预见和考虑擦黑年品可能的合理用途（如有可能，(b)新最好的信息资料；在近年来的设计人员还应进一步预测和考虑由于产品使用方法不当造成的后果。

许多产品责任诉讼案件中，由于错误地使用产品而受到伤害的原告控告生产厂所使用的材料的数据不全或是有些数据不确定，尤其(c)家，并且赢得判决）；由(e)(d)质量控制方法不适当和未经验证；是当其长期性能数据是如此的时候；一些完全不称职的人员选择材料。

对通过对上述五个问题的分析，可以得出这些问题是没有充分理由存在的结论。

尽管采用最好的材料这些问题的研究分析可以为避免这些问题的出现指明方向。

设计人员和工业界按照适当的程序进行选择方法也不能避免发生产品责任诉讼，材料选择，可以大大减少诉讼的数量。

特点和加工方法有选择材料的人们应该对材料的性质，从以上的讨论可以看出，一个全面而基本的了解。

...Machine design theoryThe machine design is through designs the new product or improves the old product project involves the application technical science. It to meet the human need thethe shape and the size, the technology each domain, mainly studies the product detailed structure basic idea, but also must study the product the personnel which in aspect the and so on manufacture, sale and use question.the designs be usually called kind of machine design work to Carries on each personnel or machine design engineer. The machine design is a creative work. Project engineer not only must have the creativity in the work, but also must in aspect and so and mechanics material, materials on mechanical drawing, kinematics, engineerig machine manufacture technology has the deep elementary knowledge.If front sues, the machine design goal is the production can meet the human need the not itself certainly discovery and technical knowledge The product. invention, the necessarily can bring the advantage to the humanity, only has when they are applied can produce on the product the benefit. Thus, should realize to carries on before the design in a specific product, must first determine whether the people do need this kind of productMust regard as the machine design is the machine design personnel carries on using product formulation analysis and a ability creative the product design, the system manufacture technology good opportunity. Grasps the project elementary knowledge to have to memorize some data and the formula is more important than. 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