机械设计外文翻译---机器和机器零件的设计
外文翻译--机器零件的设计
毕业设计(论文)外文资料翻译系部:机械工程系专业:机械工程及自动化姓名:学号:外文出处:Design of machine elements(用外文写)附件:1.外文资料翻译译文;2.外文原文。
附件1:外文资料翻译译文机器零件的设计相同的理论或方程可应用在一个一起的非常小的零件上,也可用在一个复杂的设备的大型相似件上,既然如此,毫无疑问,数学计算是绝对的和最终的。
他们都符合不同的设想,这必须由工程量决定。
有时,一台机器的零件全部计算仅仅是设计的一部分。
零件的结构和尺寸通常根据实际考虑。
另一方面,如果机器和昂贵,或者质量很重要,例如飞机,那么每一个零件都要设计计算。
当然,设计计算的目的是试图预测零件的应力和变形,以保证其安全的带动负载,这是必要的,并且其也许影响到机器的最终寿命。
当然,所有的计算依赖于这些结构材料通过试验测定的物理性能。
国际上的设计方法试图通过从一些相对简单的而基本的实验中得到一些结果,这些试验,例如结构复杂的及现代机械设计到的电压、转矩和疲劳强度。
另外,可以充分证明,一些细节,如表面粗糙度、圆角、开槽、制造公差和热处理都对机械零件的强度及使用寿命有影响。
设计和构建布局要完全详细地说明每一个细节,并且对最终产品进行必要的测试。
综上所述,机械设计是一个非常宽的工程技术领域。
例如,从设计理念到设计分析的每一个阶段,制造,市场,销售。
以下是机械设计的一般领域应考虑的主要方面的清单:①最初的设计理念②受力分析③材料的选择④外形⑤制造⑥安全性⑦环境影响⑧可靠性及寿命在没有破坏的情况下,强度是抵抗引起应力和应变的一种量度。
这些力可能是:①渐变力②瞬时力③冲击力④不断变化的力⑤温差如果一个机器的关键件损坏,整个机器必须关闭,直到修理好为止。
设计一台新机器时,关键件具有足够的抵抗破坏的能力是非常重要的。
设计者应尽可能准确地确定所有的性质、大小、方向及作用点。
机器设计不是这样,但精确的科学是这样,因此很难准确地确定所有力。
机械学英语
机械学英语
机械学(Mechanical Engineering)涉及广泛的工程领域,涵盖机械设计、制造、材料、热力学、控制等多个方面。
以下是一些常见的机械学英语术语及其解释:
1. Mechanical Engineering - 机械工程
2. Thermodynamics - 热力学
3. Fluid Mechanics - 流体力学
4. Mechanics - 力学
5. Materials Science - 材料科学
6. Manufacturing Processes - 制造工艺
7. Control Systems - 控制系统
8. Robotics - 机器人技术
9. Kinematics - 运动学
10. Dynamics - 动力学
11. Statics - 静力学
12. Heat Transfer - 热传导
13. Machine Design - 机械设计
14. CAD/CAM - 计算机辅助设计/计算机辅助制造
15. Vibration Analysis - 振动分析
16. Finite Element Analysis (FEA) - 有限元分析
17. Hydraulics - 液压学
18. Pneumatics - 气动学
19. Turbomachinery - 涡轮机械
20. Engineering Drawing - 工程制图
这些术语是在机械工程领域中常见的英语专业术语,涵盖了机械工程学科的各个方面。
深入学习这些术语可以帮助理解和掌握机械工程相关的知识和技术。
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,。
(机械设计理论)中英文对照 Machine design theory
机械设计理论The machine design theoryThe machine design is through designs the new product or improves the old product to meet the human need the application technical science. It involves the project technology each domain, mainly studies the product the size, the shape and the detailed structure basic idea, but also must study the product the personnel which in aspect the and so on manufacture, sale and use question.Carries on each kind of machine design work to be usually called designs the 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 on mechanical drawing, kinematics, engineerig material, materials mechanics and machine manufacture technology has the deep elementary knowledge.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 not 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 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.Newly designs itself can have the question occurrence which many flaws and has not been able to expect, only has after these flaws and the question are solved, can manifest new goods come into the market the product superiority. Therefore, a performance superior product is born at the same time, also is following a higher risk. Should emphas ize, if designs itself does not request to use the brand-new method, is not unnecessary merely for the goal which transform to use the new method.In 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.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. In order to carry on the effective exchange, needs to solve the following problem:(1) designs whether this product truly does need for the people? Whether there is competitive ability(2) does this product compare with other companies'' existing similar products?(3) produces this kind of product is whether economical?(4) product service is whether convenient?(5) product whether there is sale? Whether may gain?Only has the time to be able to produce the correct answer to above question. But, the product design, the manufacture and the sale only can in carry on to the above question preliminary affirmation answer foundation in. Project engineer also should through the detail drawing and the assembly drawing, carries on the consultation together with the branch of manufacture to the finally design proposal.Usually, can have some problem in the manufacture process. Possibly can request to some components size or the common difference makes some changes, causes the components the production to change easily. But, in the project change must have to pass through designs the personnel to authorize, guaranteed cannot damage the product the function. Sometimes, when in front of product assembly or in the packing foreign shipment experiment only then discovers in the design some kind of flaw. These instances exactly showed the design is a dynamic process. Always has a better method to complete the design work, designs the personnel to be supposed unceasingly diligently.Recent year, the engineerig material choice already appeared importantly. In addition, the choice process should be to the material continuously the unceasing again appraisal process. The new material unceasingly appears, but some original materials can obtain the quantity possibly can reduce. The environmental pollution, material recycling aspect and so on use, worker''s health and security frequently can attach the new limiting condition to the choice of material. In order to reduce the weight or saves the energy, possibly can request the use different material. Comes from domestic and international competition, to product service maintenance convenience request enhancement and customer''s aspect the and so on feedback pressure, can urge the people to carry on to the material reappraises. Because the material does not select when created the product responsibility lawsuit, has already had the profound influence. In addition, the material and between the material processing interdependence is already known by the people clearly.Therefore, in order to can and guarantees the quality in the reasonable cost under the premise to obtain satisfaction the result, project engineer makes engineers all to have earnestly carefully to choose, the determination and the use material.Makes any product the first step of work all is designs. Designs usually may divide into several explicit stages: (a) preliminary design; (b) functional design; (c) production design. In the preliminary design stage, the designer emphatically considered the product should have function. Usually must conceive and consider several plans, then decided this kind of thought is whether feasible; If is feasible, then should makes the further improvement to or several plans. In this stage, the question which only must consider about the choice of material is: Whether has the performance to conform to the request material to be possible to supply the choice; If no, whether has a bigger assurance all permits in the cost and the time in the limit develops one kind of new material.In the functional design and the engineering design stage, needs to make a practical feasible design. Must draw up the quite complete blueprint in this stage, chooses and determines each kind of components the material. Usually must make the prototype or the working model, and carries on the experiment to it, the appraisal product function, the reliability, the outward appearance and the service maintenance and so on. Although this kind of experiment possibly can indicate, enters in the product to the production base in front of, should replace certain materials, but, absolutely cannot this point take not earnestly chooses the material the excuse. Should unify the product the function, earnestly carefully considers the product the outward appearance, the cost and the reliability. Has the achievement very much the company when manufacture all prototypes, selects the material should the material which uses with its production in be same, and uses the similar manufacture technology as far as possible. Like this has the advantage very much to the company. The function complete prototype if cannot act according to the anticipated sales volume economically to make, or is prototypical and the official production installment has in the quality and the reliable aspect is very greatly different, then this kind of prototype does not have the great value. Project engineer is best can completely complete the material in this stage the analysis, the choice and the determination work, but is not remains it to the production design stage does. Because, is carries on in the production design stage material replacement by other people, these people are inferior to project engineer to the product all functions understanding.In the production design stage, is should completely determine with the material related main question the material, causes them to adapt with the existing equipment, can use the existingequipment economically to carry on the processing, moreover the material quantity can quite be easy to guarantee the supply.In the manufacture process, inevitably can appear to uses the material to make some changes the situation. The experience indicated that, may use certain cheap materials to take the substitute. However, in the majority situation, in will carry on the production later to change the material to have in to start before the production to change the price which the material will spend to have to be higher than. Completes the choice of material work in the design stage, may avoid the most such situations. Started after the production manufacture to appear has been possible to supply the use the new material is replaces the material the most common reason. Certainly, these new materials possibly reduce the cost, the improvement product performance. But, must carry on the earnest appraisal to the new material, guarantees its all performance all to answer the purpose. Must remember that, the new material performance and the reliable very few pictures materials on hand such understood for the people. The majority of products expiration and the product accident caused by negligence case is because in selects the new material to take in front of substitution material, not truly understood their long-term operational performance causes.The product responsibility lawsuit forces designs the personnel and the company when the choice material, uses the best procedure. In the material process, five most common questions are: (a) did not understand or cannot use about the material application aspect most newly the best information paper; (b) has not been able to foresee and to consider the dusk year possible reasonable use (for example to have the possibility, designs the personnel also to be supposed further to forecast and the consideration because product application method not when creates consequence.In r ecent years many products responsibilities lawsuit case, because wrongly uses the plaintiff which the product receives the injury to accuse produces the factory, and wins the decision); (c) uses the material data not entire perhaps some data are indefinite, works as its long-term performance data is the like this time in particular; (d) the quality control method is not suitable and not after the confirmation; (e) the personnel which completely is not competent for the post by some chooses the material.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 thepersonnel 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.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学。
机器和机器零件的设计外文文献翻译、中英文翻译、外文翻译
附录附录1Design of machine and machine elements Machine designMachine design is the art of planning or devising new or improved machines to accomplish specific purposes. In general, a machine will consist of a combination of several different mechanical elements properly designed and arranged to work together, as a whole. During the initial planning of a machine, fundamental decisions must be made concerning loading, type of kinematic elements to be used, and correct utilization of the properties of engineering materials. Economic considerations are usually of prime importance when the design of new machinery is undertaken. In general, the lowest over-all costs are designed. Consideration should be given not only to the cost of design, manufacture the necessary safety features and be of pleasing external appearance. The objective is to produce a machine which is not only sufficiently rugged to function properly for a reasonable life, but is at the same time cheap enough to be economically feasible.The engineer in charge of the design of a machine should not only have adequate technical training, but must be a man of sound judgment and wide experience, qualities which are usually acquired only after considerable time has been spent in actual professional work.Design of machine elementsThe principles of design are, of course, universal. The same theory or equations may be applied to a very small part, as in an instrument, or, to a larger but similar part used in a piece of heavy equipment. In no ease, however, should mathematical calculations be looked upon as absolute and final. They are all subject to the accuracy of the various assumptions, which must necessarily be made in engineering work. Sometimes only a portion of the total number of parts in a machine are designed on the basis of analytic calculations. The form and size of the remaining parts are designed on the basis of analytic calculations. On the other hand, if the machine is very expensive, or if weight is a factor, as in airplanes, designcomputations may then be made for almost all the parts.The purpose of the design calculations is, of course, to attempt to predict the stress or deformation in the part in order that it may sagely carry the loads, which will be imposed on it, and that it may last for the expected life of the machine. All calculations are, of course, dependent on the physical properties of the construction materials as determined by laboratory tests. A rational method of design attempts to take the results of relatively simple and fundamental tests such as tension, compression, torsion, and fatigue and apply them to all the complicated and involved situations encountered in present-day machinery.In addition, it has been amply proved that such details as surface condition, fillets, notches, manufacturing tolerances, and heat treatment have a market effect on the strength and useful life of a machine part. The design and drafting departments must specify completely all such particulars, must specify completely all such particulars, and thus exercise the necessary close control over the finished product.As mentioned above, machine design is a vast field of engineering technology. As such, it begins with the conception of an idea and follows through the various phases of design analysis, manufacturing, marketing and consumerism. The following is a list of the major areas of consideration in the general field of machine design:①Initial design conception;②Strength analysis;③Materials selection;④Appearance;⑤Manufacturing;⑥Safety;⑦Environment effects;⑨Reliability and life;Strength is a measure of the ability to resist, without fails, forces which cause stresses and strains. The forces may be;①Gradually applied;②Suddenly applied;③Applied under impact;④Applied with continuous direction reversals;⑤Applied at low or elevated temperatures.If a critical part of a machine fails, the whole machine must be shut down until a repair is made. Thus, when designing a new machine, it is extremely important that critical parts be made strong enough to prevent failure. The designer should determine as precisely as possible the nature, magnitude, direction and point of application of all forces. Machine design is mot, however, an exact science and it is, therefore, rarely possible to determine exactly all the applied forces. In addition, different samples of a specified material will exhibit somewhat different abilities to resist loads, temperatures and other environment conditions. In spite of this, design calculations based on appropriate assumptions are invaluable in the proper design of machine.Moreover, it is absolutely essential that a design engineer knows how and why parts fail so that reliable machines which require minimum maintenance can be designed. Sometimes, a failure can be serious, such as when a tire blows out on an automobile traveling at high speeds. On the other hand, a failure may be no more than a nuisance. An example is the loosening of the radiator hose in the automobile cooling system. The consequence of this latter failure is usually the loss of some radiator coolant, a condition which is readily detected and corrected.The type of load a part absorbs is just as significant as the magnitude. Generally speaking, dynamic loads with direction reversals cause greater difficulties than static loads and, therefore, fatigue strength must be considered. Another concern is whether the material is ductile or brittle. For example, brittle materials are considered to be unacceptable where fatigue is involved.In general, the design engineer must consider all possible modes of failure, which include the following:①Stress;②Deformation;③Wear;④Corrosion;⑤Vibration;⑥Environmental damage;⑦Loosening of fastening devices.The part sizes and shapes selected must also take into account many dimensional factors which produce external load effects such as geometric discontinuities, residual stresses due to forming of desired contours, and the application of interference fit joint.Selected from” design of machine elements”, 6th edition, m. f. sports, prentice-hall, inc., 1985 and “machine design”, Anthony Esposito, charles e., Merrill publishing company, 1975.Mechanical properties of materialsThe material properties can be classified into three major headings: (1) physical, (2) chemical, (3) mechanicalPhysical propertiesDensity or specific gravity, moisture content, etc., can be classified under this category.Chemical propertiesMany chemical properties come under this category. These include acidity or alkalinity, react6ivity and corrosion. The most important of these is corrosion which can be explained in layman’s terms as the resistance of the material to decay while in continuous use in a particular atmosphere.Mechanical propertiesMechanical properties include in the strength properties like tensile, compression, shear, torsion, impact, fatigue and creep. The tensile strength of a material is obtained by dividing the maximum load, which the specimen bears by the area of cross-section of the specimen.This is a curve plotted between the stress along the This is a curve plotted between the stress along the Y-axis(ordinate) and the strain along the X-axis (abscissa) in a tensile test. A material tends to change or changes its dimensions when it is loaded, depending upon the magnitude of the load. When the load is removed it can be seen that the deformation disappears. For many materials this occurs op to a certain value of the stress called the elastic limit Ap. This is depicted by the straight line relationship and a small deviation thereafter, in the stress-strain curve (fig.3.1). Within the elastic range, the limiting value of the stress up to which the stress and strain areproportional, is called the limit of proportionality Ap. In this region, the metal obeys hookes’s law, which states that the stress is proportional to strain in the elastic range of loading, (the material completely regains its original dimensions after the load is removed). In the actual plotting of the curve, the proportionality limit is obtained at a slightly lower value of the load than theelastic limit. This may be attributed to the time-lagin the regaining of the original dimensions of the material. This effect is very frequently noticed in some non-ferrous metals.Which iron and nickel exhibit clear ranges of elasticity, copper, zinc, tin, are found tobe imperfectly elastic even at relatively low values low values of stresses. Actually the elastic limit is distinguishable from the proportionality limit more clearly depending upon the sensitivity of the measuring instrument.When the load is increased beyond the elastic limit, plastic deformation starts. Simultaneously the specimen gets work-hardened. A point is reached when the deformation starts to occur more rapidly than the increasing load. This point is called they yield point Q. the metal which was resisting the load till then, starts to deform somewhat rapidly, i. e., yield. The yield stress is called yield limit Ay.The elongation of the specimen continues from Q to S and then to T. The stress-strain relation in this plastic flow period is indicated by the portion QRST of the curve. At the specimen breaks, and this load is called the breaking load. The value of the maximum load S divided by the original cross-sectional area of the specimen is referredto as the ultimate tensile strength of the metal or simply the tensile strength Au. Logically speaking, once the elastic limit is exceeded, the metal should start to yield, and finally break, without any increase in the value of stress. But the curve records an increased stress even after the elastic limit is exceeded. Two reasons can be given for this behavior:①The strain hardening of the material;②The diminishing cross-sectional area of the specimen, suffered on account of the plastic deformation.The more plastic deformation the metal undergoes, the harder it becomes, due to work-hardening. The more the metal gets elongated the more its diameter (and hence, cross-sectional area) is decreased. This continues until the point S is reached.After S, the rate at which the reduction in area takes place, exceeds the rate at which the stress increases. Strain becomes so high that the reduction in area begins to produce a localized effect at some point. This is called necking.Reduction in cross-sectional area takes place very rapidly; so rapidly that the load value actually drops. This is indicated by ST. failure occurs at this point T.Then percentage elongation A and reduction in reduction in area W indicate the ductility or plasticity of the material:A=(L-L0)/L0*100%W=(A0-A)/A0*100%Where L0 and L are the original and the final length of the specimen; A0 and A are the original and the final cross-section area.Selected from “testing of metallic materials”Quality assurance and controlProduct quality is of paramount importance in manufacturing. If quality is allowed deteriorate, then a manufacturer will soon find sales dropping off followed by a possible business failure. Customers expect quality in the products they buy, and if a manufacturer expects to establish and maintain a name in the business, quality control and assurance functions must be established and maintained before, throughout, andafter the production process. Generally speaking, quality assurance encompasses all activities aimed at maintaining quality, including quality control. Quality assurance can be divided into three major areas. These include the following:①Source and receiving inspection before manufacturing;②In-process quality control during manufacturing;③Quality assurance after manufacturing.Quality control after manufacture includes warranties and product service extended to the users of the product.Source and receiving inspection before manufacturingQuality assurance often begins ling before any actual manufacturing takes place. This may be done through source inspections conducted at the plants that supply materials, discrete parts, or subassem blies to manufacturer. The manufacturer’s source inspector travels to the supplier factory and inspects raw material or premanufactured parts and assemblies. Source inspections present an opportunity for the manufacturer to sort out and reject raw material s or parts before they are shipped to the manufacturer’s production facility.The responsibility of the source inspector is to check materials and parts against design specifications and to reject the item if specifications are not met. Source inspections may include many of the same inspections that will be used during production. Included in these are:①Visual inspection;②Metallurgical testing;③Dimensional inspection;④Destructive and nondestructive inspection;⑤Performance inspection.Visual inspectionsVisual inspections examine a product or material for such specifications as color, texture, surface finish, or overall appearance of an assembly to determine if there are any obvious deletions of major parts or hardware.Metallurgical testingMetallurgical testing is often an important part of source inspection, especially if theprimary raw material for manufacturing is stock metal such as bar stock or structural materials. Metals testing can involve all the major types of inspections including visual, chemical, spectrographic, and mechanical, which include hardness, tensile, shear, compression, and spectr5ographic analysis for alloy content. Metallurgical testing can be either destructive or nondestructive.Dimensional inspectionFew areas of quality control are as important in manufactured products as dimensional requirements. Dimensions are as important in source inspection as they are in the manufacturing process. This is especially critical if the source supplies parts for an assembly. Dimensions are inspected at the source factory using standard measuring tools plus special fit, form, and function gages that may required. Meeting dimensional specifications is critical to interchangeability of manufactured parts and to the successful assembly of many parts into complex assemblies such as autos, ships, aircraft, and other multipart products.Destructive and nondestructive inspectionIn some cases it may be necessary for the source inspections to call for destructive or nondestructive tests on raw materials or p0arts and assemblies. This is particularly true when large amounts of stock raw materials are involved. For example it may be necessary to inspect castings for flaws by radiographic, magnetic particle, or dye penetrant techniques before they are shipped to the manufacturer for final machining. Specifications calling for burn-in time for electronics or endurance run tests for mechanical components are further examples of nondestructive tests.It is sometimes necessary to test material and parts to destruction, but because of the costs and time involved destructive testing is avoided whenever possible. Examples include pressure tests to determine if safety factors are adequate in the design. Destructive tests are probably more frequent in the testing of prototype designs than in routine inspection of raw material or parts. Once design specifications are known to be met in regard to the strength of materials, it is often not necessary to test further parts to destruction unless they are genuinely suspect.Performance inspectionPerformance inspections involve checking the function of assemblies, especially those of complex mechanical systems, prior to installation in other products. Examples include electronic equipment subcomponents, aircraft and auto engines, pumps, valves, and other mechanical systems requiring performance evaluation prior to their shipment and final installation.Selected form “modern materials and manufacturing process”Electro-hydraulic drum brakesApplicationThe YWW series electro-hydraulic brake is a normally closed brake, suitable for horizontal mounting. It is mainly used in portal cranes, bucket stacker/reclaimers’slewing mechanism.The YKW series electro-hydraulic brake is a normally opened brake, suitable for horizontal mounting, employing a thruster as actuator. with the foot controlling switch the operator can release or close the brake. It is mainly used for deceleration braking of portal cranes’slewing mechanism. In a non-operating state the machinery can be braked by a manual close device.The RKW series brake is a normally opened brake, which is operated by foot driven hydraulic pump, suitable for horizontal mounting. Mainly used in the slewing mechanism of middle and small portal cranes. When needed, the brake is activated by a manual closed device.Main design featuresInterlocking shoes balancing devices (patented technology) constantly equalizes the clearance of brake shoes on both sides and made adjustment unnecessary, thus avoiding one side of the brake lining sticking to the brake wheel. The brake is equipped with a shoed autoaligning device.Main hinge points are equipped with self-lubricating bearing, making high efficiency of transmission, long service life. Lubricating is unnecessary during operation.Adjustable bracket ensure the brake works well.The brake spring is arranged inside a square tube and a surveyor’s rod is placed onone side. It is easy to read braking torque value and avoid measuring and computing.Brake lining is of card whole-piece shaping structure, easy to replace. Brake linings of various materials such as half-metal (non-asbestos) hard and half-hard, soft (including asbestos) substance are available for customers to choose.All adopt the company’s new types of thruster as corollary equipment which work accurately and have long life.Hydraulic Power TransmissionThe Two Types Of Power TransmissionIn hydraulic power transmission the apparatus (pump) used for conversion of the mechanical (or electrical,thermal) energy to hydraulic energy is arranged on the input of the kinematic chain ,and the apparatus (motor) used for conversion of the hydraulic energy to mechanical energy is arranged on the output (fig.2-1)The theoretical design of the energy converters depends on the component of the bernouilli equation to be used for hydraulic power transmission.In systerms where, mainly, hydrostatic pressure is utilized, displacement (hydrostatic) pumps and motors are used, while in those where the hydrodynamic pressure is utilized is utilized gor power transmission hydrodynamic energy converters (e.g. centrifugal pumps) are used.The specific characteristic of the energy converters is the weight required for transmission of unit power. It can be demonstrated that the use of hydrostatic energy converters for the low and medium powers, and of hydrodynamic energy converters of high power are more favorite (fig.2-2). This is the main reason why hydrostatic energy converters are used in industrial apparatus. transformation of the energy in hydraulic transmission.1.driving motor (electric, diesel engine);2.mechanical energy;3.pump;4.hydraulic energy;5.hydraulic motor;5.mechanical energy;6.load variation of the mass per unit power in hydrostatic and hydrodynamic energy converters1、hydrostatic; 2.hydrodynamicOnly displacement energy converters are dealt with in the following. The elements performing converters provide one or several size. Expansion of the working chambers in a pump is produced by the external energy admitted, and in the motor by the hydraulic energy. Inflow of the fluid occurs during expansion of the working chamber, while the outflow (displacement) is realized during contraction. Such devices are usually called displacement energy converters.The Hydrostatic PowerIn order to have a fluid of volume V1 flowing in a vessel at pressure work spent on compression W1 and transfer of the process, let us imagine a piston mechanism (fig.2-3(a)) which may be connected with the aid of valves Z0 and Z1 to the external medium under pressure P0 and reservoir of pressure p1.in the upper position of the piston (x=x0) with Z0 open the cylinder chamber is filled with fluid of volume V0 and pressure P0. now shut the value Z0 and start the piston moving downwards. If Z1 is shut the fluid volume in position X=X1 of the piston decreases from V0 to V1, while the pressure rises to P1. the external work required for actuation of the piston (assuming isothermal change) isW1=-∫0x0(P-P0)Adx=-∫v1v0(P-P0)dvSelect from Hydraulic Power Transmission机器和机器零件的设计机器设计机器设计为了特定的目的而发明或改进机器的一种艺术。
机械类英语论文及翻译
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 ;Rules for Design ;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 previously done by men, such as computation, assembly, or servicing. With the objective wholly or partly.In the design preliminary stage, should allow to design the personnel fullyto 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 become apparent, 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, whetherdone 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 thesuitable 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 spur gears , 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 thematerial, 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 not 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 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 certainlycannot 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.外文论文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。
文献翻译原文-机器零件的设计
编号:毕业设计(论文)外文翻译(原文)院(系):机电工程学院专业:机械设计制造及其自动化学生姓名:学号:指导教师单位:姓名:职称:2014年 5 月23 日Design of machine elementsThe principles of design are, of course, universal. The same theory or equations may be applied to a very small part, as in an instrument, or, to a larger but similar part used in a piece of heavy equipment. In no ease, however, should mathematical calculations be looked upon as absolute and final. They are all subject to the accuracy of the various assumptions, which must necessarily be made in engineering work. Sometimes only a portion of the total number of parts in a machine are designed on the basis of analytic calculations. The form and size of the remaining parts are designed on the basis of analytic calculations. On the other hand, if the machine is very expensive, or if weight is a factor, as in airplanes, design computations may then be made for almost all the parts.The purpose of the design calculations is, of course, to attempt to predict the stress or deformation in the part in order that it may sagely carry the loads, which will be imposed on it, and that it may last for the expected life of the machine. All calculations are, of course, dependent on the physical properties of the construction materials as determined by laboratory tests. A rational method of design attempts to take the results of relatively simple and fundamental tests such as tension, compression, torsion, and fatigue and apply them to all the complicated and involved situations encountered in present-day machinery.In addition, it has been amply proved that such details as surface condition, fillets, notches, manufacturing tolerances, and heat treatment have a market effect on the strength and useful life of a machine part. The design and drafting departments must specify completely all such particulars, must specify completely all such particulars, and thus exercise the necessary close control over the finished product.As mentioned above, machine design is a vast field of engineering technology. As such, it begins with the conception of an idea and follows through the various phases of design analysis, manufacturing, marketing and consumerism. The following is a list of the major areas of consideration in the general field of machine design:①Initial design conception;②Strength analysis;③Materials selection;④Appearance;⑤Manufacturing;⑥Safety;⑦Environment effects;⑨Reliability and life;Strength is a measure of the ability to resist, without fails, forces which cause stresses and strains. The forces may be;①Gradually applied;②Suddenly applied;③Applied under impact;④Applied with continuous direction reversals;⑤Applied at low or elevated temperatures.If a critical part of a machine fails, the whole machine must be shut down until a repair is made. Thus, when designing a new machine, it is extremely important that critical parts be made strongenough to prevent failure. The designer should determine as precisely as possible the nature, magnitude, direction and point of application of all forces. Machine design is mot, however, an exact science and it is, therefore, rarely possible to determine exactly all the applied forces. In addition, different samples of a specified material will exhibit somewhat different abilities to resist loads, temperatures and other environment conditions. In spite of this, design calculations based on appropriate assumptions are invaluable in the proper design of machine.Moreover, it is absolutely essential that a design engineer knows how and why parts fail so that reliable machines which require minimum maintenance can be designed. Sometimes, a failure can be serious, such as when a tire blows out on an automobile traveling at high speeds. On the other hand, a failure may be no more than a nuisance. An example is the loosening of the radiator hose in the automobile cooling system. The consequence of this latter failure is usually the loss of some radiator coolant, a condition which is readily detected and corrected.The type of load a part absorbs is just as significant as the magnitude. Generally speaking, dynamic loads with direction reversals cause greater difficulties than static loads and, therefore, fatigue strength must be considered. Another concern is whether the material is ductile or brittle. For example, brittle materials are considered to be unacceptable where fatigue is involved.In general, the design engineer must consider all possible modes of failure, which include the following:①Stress;②Deformation;③Wear;④Corrosion;⑤Vibration;⑥Environmental damage;⑦Loosening of fastening devices.The part sizes and shapes selected must also take into account many dimensional factors which produce external load effects such as geometric discontinuities, residual stresses due to forming of desired contours, and the application of interference fit joint.Mechanical properties of materialsThe material properties can be classified into three major headings: (1) physical, (2) chemical, (3) mechanicalPhysical propertiesDensity or specific gravity, moisture content, etc., can be classified under this category. Chemical propertiesMany chemical properties come under this category. These include acidity or alkalinity, react6ivity and corrosion. The most important of these is corrosion which can be explained in layman’s terms as the resistance of the material to decay while in continuous use in a particular atmosphere.Mechanical propertiesMechanical properties include in the strength properties like tensile, compression, shear, torsion, impact, fatigue and creep. The tensile strength of a material is obtained by dividing the maximum load, which the specimen bears by the area of cross-section of the specimen.This is a curve plotted between the stress along the This is a curve plotted between the stress along the Y-axis(ordinate) and the strain along the X-axis (abscissa) in a tensile test. Amaterial tends to change or changes its dimensions when it is loaded, depending upon the magnitude of the load. When the load is removed it can be seen that the deformation disappears. For many materials this occurs op to a certain value of the stress called the elastic limit Ap. This is depicted by the straight line relationship and a small deviation thereafter, in the stress-strain curve (fig.3.1). Within the elastic range, the limiting value of the stress up to which the stress and strain are proportional, is called the limit of proportionality Ap. In this region, the metal obeys hookes’s law, which states that the stress is proportional to strain in the elastic range of loading, (the material completely regains its original dimensions after the load is removed). In the actual plotting of the curve, the proportionality limit is obtained at a slightly lower value of the load than theelastic limit. This may be attributed to the time-lagin the regaining of the original dimensions of the material. This effect is very frequently noticed in some non-ferrous metals.Which iron and nickel exhibit clear ranges of elasticity, copper, zinc, tin, are found to be imperfectly elastic even at relatively low values low values of stresses. Actually the elastic limit is distinguishable from the proportionality limit more clearly depending upon the sensitivity of the measuring instrument.When the load is increased beyond the elastic limit, plastic deformation starts. Simultaneously the specimen gets work-hardened. A point is reached when the deformation starts to occur more rapidly than the increasing load. This point is called they yield point Q. the metal which was resisting the load till then, starts to deform somewhat rapidly, i. e., yield. The yield stress is called yield limit Ay.The elongation of the specimen continues from Q to S and then to T. The stress-strain relation in this plastic flow period is indicated by the portion QRST of the curve. At the specimen breaks, and this load is called the breaking load. The value of the maximum load S divided by the original cross-sectional area of the specimen is referred to as the ultimate tensile strength of the metal or simply the tensile strength Au.Logically speaking, once the elastic limit is exceeded, the metal should start to yield, and finally break, without any increase in the value of stress. But the curve records an increased stress evenafter the elastic limit is exceeded. Two reasons can be given for this behavior:①The strain hardening of the material;②The diminishing cross-sectional area of the specimen, suffered on account of the plastic deformation.The more plastic deformation the metal undergoes, the harder it becomes, due to work-hardening. The more the metal gets elongated the more its diameter (and hence, cross-sectional area) is decreased. This continues until the point S is reached.After S, the rate at which the reduction in area takes place, exceeds the rate at which the stress increases. Strain becomes so high that the reduction in area begins to produce a localized effect at some point. This is called necking.Reduction in cross-sectional area takes place very rapidly; so rapidly that the load value actually drops. This is indicated by ST. failure occurs at this point T.Then percentage elongation A and reduction in reduction in area W indicate the ductility or plasticity of the material:A=(L-L0)/L0*100%W=(A0-A)/A0*100%Where L0 and L are the original and the final length of the specimen; A0 and A are the original and the final cross-section area.Quality assurance and controlProduct quality is of paramount importance in manufacturing. If quality is allowed deteriorate, then a manufacturer will soon find sales dropping off followed by a possible business failure. Customers expect quality in the products they buy, and if a manufacturer expects to establish and maintain a name in the business, quality control and assurance functions must be established and maintained before, throughout, and after the production process. Generally speaking, quality assurance encompasses all activities aimed at maintaining quality, including quality control. Quality assurance can be divided into three major areas. These include the following:①Source and receiving inspection before manufacturing;②In-process quality control during manufacturing;③Quality assurance after manufacturing.Quality control after manufacture includes warranties and product service extended to the users of the product.Source and receiving inspection before manufacturingQuality assurance often begins ling before any actual manufacturing takes place. This may be done through source inspections conducted at the plants that supply materials, discrete parts, or subassemblies to manufacturer. The manufacturer’s source inspector travels to the supplier factory and inspects raw material or premanufactured parts and assemblies. Source inspections present an opportunity for the manufacturer to sort out and reject raw materials or parts before they are shipped to the manufacturer’s production facility.The responsibility of the source inspector is to check materials and parts against design specifications and to reject the item if specifications are not met. Source inspections may include many of the same inspections that will be used during production. Included in these are:①Visual inspection;②Metallurgical testing;③Dimensional inspection;④Destructive and nondestructive inspection;⑤Performance inspection.Visual inspectionsVisual inspections examine a product or material for such specifications as color, texture, surface finish, or overall appearance of an assembly to determine if there are any obvious deletions of major parts or hardware.Metallurgical testingMetallurgical testing is often an important part of source inspection, especially if the primary raw material for manufacturing is stock metal such as bar stock or structural materials. Metals testing can involve all the major types of inspections including visual, chemical, spectrographic, and mechanical, which include hardness, tensile, shear, compression, and spectr5ographic analysis for alloy content. Metallurgical testing can be either destructive or nondestructive.Dimensional inspectionFew areas of quality control are as important in manufactured products as dimensional requirements. Dimensions are as important in source inspection as they are in the manufacturing process. This is especially critical if the source supplies parts for an assembly. Dimensions are inspected at the source factory using standard measuring tools plus special fit, form, and function gages that may required. Meeting dimensional specifications is critical to interchangeability of manufactured parts and to the successful assembly of many parts into complex assemblies such as autos, ships, aircraft, and other multipart products.Destructive and nondestructive inspectionIn some cases it may be necessary for the source inspections to call for destructive or nondestructive tests on raw materials or p0arts and assemblies. This is particularly true when large amounts of stock raw materials are involved. For example it may be necessary to inspect castings for flaws by radiographic, magnetic particle, or dye penetrant techniques before they are shipped to the manufacturer for final machining. Specifications calling for burn-in time for electronics or endurance run tests for mechanical components are further examples of nondestructive tests.It is sometimes necessary to test material and parts to destruction, but because of the costs and time involved destructive testing is avoided whenever possible. Examples include pressure tests to determine if safety factors are adequate in the design. Destructive tests are probably more frequent in the testing of prototype designs than in routine inspection of raw material or parts. Once design specifications are known to be met in regard to the strength of materials, it is often not necessary to test further parts to destruction unless they are genuinely suspect.Performance inspectionPerformance inspections involve checking the function of assemblies, especially those of complex mechanical systems, prior to installation in other products. Examples include electronic equipment subcomponents, aircraft and auto engines, pumps, valves, and other mechanical systems requiring performance evaluation prior to their shipment and final installation.。
机械外文翻译--机构与机器
Mechanism and MachinesA system that transmits forces in a predetermined manner to accomplish specific objectives may be considered a machine. A mechanism may be defined in a similar manner, but the term mechanism is usually applied to a system where the principal function is to transmit motion. Kinematics is the study of motion in mechanism, while the analysis of force and torques in machined is called dynamics.Once the need for a machine or mechanism with given characteristics is identified, the design process begins. Detailed analysis of displacements, velocities, and accelerations is usually required. This part of the design process is then followed by analysis of force and torques. The design process may continue long after first model have been produce and include redesigns of component that affect velocities, accelerations, force, and torques. In order to successfully compete form year to year, most manufacturers must continuously modify their product and their methods of production. Increases in production rate, upgrading of product performance, redesign for cost and weight reduction, and motion analysis of new product lines are frequently required. Success may hinge on the correct kinematic and dynamic analysis of the problem.Many of the basic linkage configurations have been incorporate into machines designed centuries ago, and the term we use to describe then have change over the year. Thus, definitions and terminology will not be consistent throughout the technical literature. In most cases, however, meanings will be clear form the context of the descriptive matter. A few terms of particular interest to the study of kinematic and dynamics of machines are define below.Link A link is one of the rigid bodies or members joined together to form a kinematic chain. The term rigid link or sometimes simply link is an idealization used in the study of that does not consider small deflections due to strains in machine members. A perfectly rigid or inextensible link can exist only as a textbook type of model of a real machine member. For typical machine part, maximum dimension changes are of only a one-thousandth of the part length. We are justified in neglecting this small motion when considering the much greater motion characteristic of most mechanisms. The word link is used in a general sense to include cams, gears, and other machine members in addition to cranks, connecting rods and otherpin-connected components.Degrees-of-freedom The number of degrees-of-freedom of a linkage is the number of independent parameters required to position of every link relative to the frame or fixed link. If the instantaneous configuration of a system may be completely defined by specifying one independent variable, that system has onedegree-of-freedom. Most practical mechanisms have one degree-of-freedom.An unconstrained rigid body has six degrees-of-freedom: translation in three coordinates and rotation about three coordinate axes. If the body is restricted to motion in a plane, there are three degrees-of-freedom: translation in two coordinate directions and rotation within the plane.Lower and Higher Pairs Connections between rigid bodies consist of lower andhigher pairs of elements. The two elements of a lower pair have theoretical surface contact with one another, while the two elements of a higher pair have theoretical point or line contact (if we disregard deflections).Lower pairs are desirable from a design standpoint since the load at the joint and the resultant wear is spread over the contact surface. Thus, geometric changes or failure due to high contact stresses and excessive wear may be prevented.Mechanism A mechanism is a kinematic chain in which one link is considered fixed for the purpose of analysis, but motion is possible in other links. As noted above, the link designated as the fixed link need not actually be stationary relative to the surface of the earth. A kinematic chain is usually identified as a mechanism if its primary purpose is the modification or transmission of motion.Machine A mechanism designed for the purpose of transmitting forces or torques is usually called a machine.Engine A machine that involves conversion of energy to produce mechanical power is commonly called an engine. Thus, the crankshaft, connecting rod, piston, and cylinder of an automotive engine would be an engine by the above definitions, while other drive train components such as the transmission, differential, and universal joint would be considered machines. Machines and engines may have the same configuration as other mechanisms that do not convert energy and are not intended to transmit significant levels of force or torque. Thus, for the purpose of kinematic analysis, the above distinction between mechanism, machine, and engine may be of only academic importance.A Mechanism has been defined as “a combination of rigid or resistant bodies so formed and connected that they move upon each other with definite relative motion.”Mechanisms form the basic geometrical elements of many mechanical devices including automatic packaging machinery, typewriters, mechanical toys, textile machinery, and others. A mechanism typically is designed to create a desired motion of a rigid body relative to a reference member. Kinematic design of mechanisms is often the first step in the design of a complete machine. When forces are considered, the additional problems of dynamics, bearing loads, stresses, lubrication, and the like are introduced, and the larger problem becomes one of machine design.The function of a mechanism is to transmit or transform motion from one rigid body to another as part of the action of a machine. There are three types of common mechanical devices that can be used as basic elements of a mechanism.Gear Systems Gear systems, in which toothed members in contact transmit motion between rotating shafts. Gears normally are used for the transmission of motion with a constant angular velocity ratio, although noncircular gears can be used for nonuniform transmission of motion.Cam Systems Cam systems, where a uniform motion of an input member is converted into a nonuniform motion of the output member. The output motion may be either shaft rotation, slider translation, or other follower motions created by directcontact between the input cam shape and the follower. The kinematic design of cams involves the analytical or graphical specification of the cam surface shape required to drive the follower with a motion that is a prescribed function of the input motion.Plane and Spatial Linkages They are also useful in creating mechanical motions for a point or rigid body. Linkages can be used for three basic tasks.(1) Rigid body guidance. A rigid body guidance mechanism is used to guide a rigid body through a series of prescribed positions in space.(2) Path generation mechanism will guide a point on a rigid body through a series of points on a specified path in space.(3) Function generation. A mechanism that creates an output motion that is a specified function of the input motion.Mechanisms may be categorized in several different ways to emphasize their similarities and differences. One such grouping divides mechanisms into planar, spherical, and spatial categories. All three groups have many things in common; the criterion which distinguishes the groups, however, is to be found in the characteristics of the motions of the links.A planar mechanism is one in which all particles describe plane curves in space and all these curves lie in parallel planes; i.e. the loci of all points are plane curves parallel to a single common planar mechanism in its true size and shape on a single drawing or figure. The plane four-bar linkage, the plate cam and follower, and the slider-crank mechanism are familiar examples of planar mechanisms. The vast majority of mechanisms in use today are planar.A spherical mechanism is one in which each link has some point which remains stationary as the linkage moves and in which the stationary points of all links lie at a common location; i.e., the locus of each point is a curve contained in a spherical surface, and the spherical surfaces defined by several arbitrarily chosen points are all concentric. The motions of all particles can therefore be completely described by their radial projections, or “shadows,” on the surface of a sphere with properly chosen center. Hooke’s universal joint is perhaps the most familiar example of a spherical mechanism.Spatial mechanisms, on the other hand, include no restrictions on the relative motions of the particles. The motion transformation is not necessarily coplanar, nor must it be concentric. A spatial mechanism may have particles with loci of double curvature. Any linkage which contains a screw pair, for example, is a spatial mechanism, since the relative motion within a screw pair is helical.机构与机器一个系统,它按预先确定的方式来传输动力完成的具体的目标也许可以被认为是机器。
机械设计基础(英汉互译)
Fundamentals of Mechanical DesignMechanical design means the design of things and systems of things and systems of a mechanical nature-machines, products, structures, devices, and instruments. For the most part mechanical design utilizes mathematics, the materials sciences, and the engineering-mechanics sciences.The total design process is of interest to us. How does it begin? Does the engineer simply sit down at his desk with a blank sheet of paper? And, as he jots down some ideas, what happens next? What factors influence or control the decisions which have to be made? Finally, then, how does this design process end?Sometimes, but not always, design begins when an engineer recognizes a need and decides to do something about it. Recognition of the need phrasing it in so many words often constitute a highly creative act because the need may be only a vague discontent, a feeling of uneasiness, or a sensing that something is not right.The need is usually not evident at all. For example, the need to do something about a food-packaging machine may be indicated by the noise level, by the variation in package weight, and by slight but perceptible variations in the quality of the packaging or wrap.There is a distinct difference between the statement of the statement of the need and the identification of the problem which follows this statement. The problem is more specific. If the need is for cleaner air, the problem might be that of reducing the dust discharge from power-plant stacks, or reducing the quantity of irritants from automotive exhausts.Definition of the problem must include all the specifications for the thing that is to be designed. The specifications are the input and output quantities, the characteristics and dimensions of the space the thing must occupy and all the limitations on these quantities. We can regard the thing to be designed as something in a black box. In this case we must specify the inputs and outputs of the box together with their characteristics and limitations. The specifications define the cost, the number to be manufactured, the expected life, the range, the operating temperature, and the reliability.There are many implied specifications which result either from the designer’s particular environment or from the problem itself. The manufacturing processes which are available, together with the facilities of a certain plant, constitute restrictions on a designer’s freedom, and hence are a part of the implied specifications. A small plant, for instance, may not own cold-working machinery. Knowing this, the designer selects other metal-processing methods which can be performed in the plant. The labor skills available and the competitive situation also constitute implied specifications.After the problem has been defined and a set of written and implied specifications has been obtained, the next step in design is the synthesis of an optimum solution. Now synthesis cannot take place without both analysis and optimization because the system under design must be analysis and optimization because the system under design must be analyzed to determine whether the performance complies with the specifications.The design is an iterative process in which we proceed through several steps, evaluate the results, and then return to an earlier phase of the procedure. Thus we may synthesize several components of a system, analyze and optimize them, and return to syntheses to see what effect this has on the remaining parts of the system. Both analysis and optimization require that we construct or devise abstract models of the system which will admit some form of mathematical analysis. Wecall these models mathematical models. In creating them it is our hope that we can find one which will simulate the real physical system very well.Evaluation is a significant phase of the total design process. Evaluation is the final proof of a successful design, which usually involves the testing of a prototype in the laboratory. Here we wish to discover if the design really satisfies the need or needs. Is it reliable? will it compete successfully with similar products? Is it economical to manufacture and to use? Is it easily maintained and adjusted? Can a profit be made from its sale or use?Communicating the design to others is the final, vital step in the design process. Undoubtedly many great designs, inventions, and creative works have been lost to mankind simply because the originators were unable or unwilling to explain their accomplishments to others. Presentation is a selling job. The engineer, when presenting a new solution to administrative, management, or supervisory persons, is attempting to them that this solution is a better one. Unless this can be done successfully, the time and effort spent on obtaining the solution have been largely wasted.Basically, there are only three means of communication available to us. These are the written, the oral. And the graphical forms. Therefore the successful engineer will be technically competent and versatile in all three forms of communication. A technically competent person who lacks ability in any one of these forms is severely handicapped. If ability in all three forms is locking, no one will ever know how competent that person is!The competent engineer should not be afraid of the possibility of not succeeding in a presentation. In fact, occasional failure should be expected because failure or criticism seems to accompany every really creative idea. There is a great deal to be learned form a failure, and the greatest gains are obtained by those willing to risk defeat. In the final analysis, the real failure would lie in deciding not to make the presentation at all.机械设计基础机械设计是指机械装置和机械系统——机器、产品、结构、设备和仪器的设计。
机械工程及自动化专业外文翻译--机械系统设计
外文原文:INTRODUCTIONThe rapid development of science and technology, product features requirements of the growing number and complexity of the increase in life expectancy shortened, replacement faster. However, the design of the products, especially mechanical products in the design means, is unable, failed to keep pace with the needs of the times. At present, computer-aided product design drawings, design, manufacturing, production planning has been a relatively extensive and in-depth study and achieved initial results, and product development programmes of the early computer-aided design is far from meeting a need. To this end, the author read a lot of literature on the basis of a summary of the design and scholars at home and abroad to design the method used, and discussed the various methods of organic link between product design and mechanical Computer trend of development.Under the current domestic and foreign scholars to design machinery design methods used by the main features of the programme can be summed up modern design for the following four major types.1, systematic design methodSystematic design of the main features are: design as from a number of design elements of a system, every design element of independence, there are various elements of the organic links and a level of all the design elements Combined, you can design systems to achieve the task.Systematic design idea in the 1970s by the German scholar Professor Pahl and Beitz, a system based on the theory, developed a design of the general pattern, and advocate of the design work should be rational. German Engineers Association in this on the basis of design, develop standards VDI2221 "technology systems and product development design methods.The development of the product design process of mechanical model, basically follow the German standards VDI2221 the design. In addition, many of our product design and scholars in the programme design and also learn from other developed countries cited the systematic design, which is representative:(1) The user needs as the product concept of functional characteristics, structural design and part design, process planning, operations control, and so on the basis of the product development process of the macro, the use of Quality Function layout methods, systems and information needs of users will be reasonable and effective Andconverted to the various stages of product development objectives and operations control technology means a point of order.(2) products as organisms on the level of life, and life systems through the use of the product design process can demand level of success and realize the concept of functional requirements of the specific levels and product design level. At the same time using the system icons to life the abstract expression of the functional requirements of products, product features a system structure.(3) the mechanical design system in the application of science into two basic questions: First, to design products as a system to process, to determine the best of its components (modules) and their mutual relations and the other is the product design Process as a system, according to the design objectives, correct and reasonable to determine the design of all aspects of the work and the various design stage.As each designer to study issues and to consider the perspective of the different emphases, to design a programme of specific research methods also differ. Here are some representative of the systematic design methods.1.1 design elements ofWith five design elements (functions, effects, effects of vector, shape and surface elements parameters) described "product solution" that a product design elements of the five identified, all the characteristics of products and value characteristics already identified. Chinese scholars have also adopted similar design methods described product of the original understanding.1.2 graphical modeling lawDevelopment of the design analysis and guidance systems "KALEIT, with a clear level of the graphic description of the product structure and functions related to the abstract information, and the system structure and function of the graphical modeling, and the function of the connection between.Will be assisted design divided into two methods and information exchange, the use of Nijssen information analysis methods can be used graphic symbols, with a variety of semantic model structure, the integration can be described conditions can be divided into binding type, can relations between any combination of features , Will design solutions and information technology integration, the design process to achieve a different level of abstraction of information between the graphical modeling.The literature [11] semantic network design as a design tool in the development of the semantic network design ASK, using nodes and a network of lines describingthe design, components of the node that the unit design tasks, functions, components or processing Equipment, etc.), and lines used to adjust the definition node between different semantic relations, which in the design process for all the activities and results of pre-built model, the early design requirements to the definition of a specific structure can be described by the relationship between The definition of the expression, and a computer-aided design process from abstract to concrete leap.1.3 "idea" - "design" lawWill be divided into product design "concept" and "design" in two stages. "Idea" phase of the mission is to seek, select and design portfolio to meet the requirements of the original understanding of tasks. "Design" stage of work is the concrete realization of the original understanding of the conceptual stage.The programme will be "ideas" for the specific description: According to a suitable functional structure, designed to meet the requirements of the mandate of the original understanding. Functional structure of the sub-function by "structural elements" to achieve, and "structural elements" of the physical connection between the definition of "functional carrier", "functional carrier" and "structural elements" and formation of the interaction between the functional diagram ( Mechanical movement diagram). Programme of "design" is based on functional diagram, the first qualitative description of all the "functional carrier" and "structural elements", then all the quantitative description of "structural elements" and connecting pieces ( "functional vector") the shape and location have The structure of. Roper, H. use of graph theory theory, the help from his definition of "total design unit (GE)", "structure elements (KE)", "functional structure elements (FKE)", "connecting structure elements (VKE)", "Structural parts (KT)", "structural elements parts (KET)" concept, and describes elements of size, location and transmission parameters of the relationship between the number of thumbs, the design intuitive design experts design "stage.From the design methodology of the point of view, the design task will be clear after the design work is divided into three steps: 1) access to functions and functional structure (referred to as "functional"), 2) find effects (referred to as the "effect"); ) To find structure (referred to as "the configuration of the Rules"). And use the following four strategies described machinery idea stage of the process: Strategy 1: were considered "functional" and "effect" and "configuration rules." Therefore, we can work in various steps to create variations in the respective programmes, resulting inthe original understanding of the broad spectrum. Strategy 2: "effect" and "configuration rules" (including the designer to create the rules) association, to consider a separate function (usually associated with the design task). At this point, to identify the typical configuration rules and their effects need to have a wealth of experience, the programme spectrum far less than a strategy of the programme spectrum. Strategy 3: "functional" and "effect", "configuration rules" are closely related. Applicable to the function, and the configuration of the rules of no choice, with special requirements of the areas, such as ultra-small machinery, large machinery, high-value function parts, and those with special requirements of the functional components, and so on. Strategy 4: In view of the structural design requirements of the solution. The strategy starting from the existing parts, through different parts of the order and connection, was expected to function.1.4 Matrix DesignIn the programme design process used in "requirement - to" logic tree ( "or" tree) described requirements, the relationship between the function, to satisfy the requirements of functional design solution set, a different design. According to "request - to" logic tree establishment of a "request - to" association matrix, meet the requirements necessary to describe the complex relationship between function, expressed functional requirements and the relationship between the one-to-one.otaetal will matrix as a mechanical system design basis, the mechanical system design space as a functional decomposition of space, only that each sub-space design of a module, in the abstract phase of the high-level, with each module design movement conversion matrix And a vector for the operation of restraint that in the abstract phase of the low-rise, each module design parameters were expressed as a matrix and the equation of motion.1.5 bond graph LawWill form a system components into the function to generate energy, energy consumption, changing energy forms, such as various types of energy transmission and use of bond graph of the function of the components that will be based on the functions of the model and bonding with plans to achieve functional The automatic generation of structural and functional structure and bonding between the automatic conversion plans to seek bond graph generated by a number of design methods.2, modular design structureFrom the perspective of planning products: the definition of its mandate todesign features of the product structure is based on the use of existing products (such as GM parts components, etc.) described the design task, that is, when the mandate of decomposition on each task to consider whether there is the corresponding Solutions products, so that in the planning stages of product design tasks to eliminate the contradictions that might exist in the early forecast production capacity, costs and the development of the process of designing the plan adjustable, which can improve the design efficiency and design of reliability, At the same time also reduce the cost of new products. Feldmann will describe the function of the design task is divided into four levels of product structure, (1) products → (2) functional components → (3) main function components → (4) functional components. And the use of application-oriented features of the directory structure, a more specific functional components of the qualitative and quantitative description. At the same time developed for early in the product development and design tools used by early STRAT.Machinery specialized for most of that function can be used existing product solutions and new solutions with only a small number of special features, therefore, for the use of mechanical design features of the product structure, machinery specialized for the evaluation of the design, manufacture risk is very beneficial.Functional Analysis of the products promoted on the basis of the product is broken down into a function of one or more of the basic modular structure, through the selection and combination of these modular structure formed into various products. These basic structure can be parts, components, or even a system. The ideal modular structure should be standardized interface (connectivity and with the Department of), and is serialized, universal, integrated, hierarchical, flexible, economic, with interchangeable, compatibility and relevance of the . China's combination of software component technology and CAD technology, design and composition of deformation design combined, according to grade modular theory, machine processing center will be divided into Youdadaoxiao product level, component level, component-level and component level, and use CAD technology and expertise to their portfolio into different species, different specifications of the functional module, the module from the combination of these functions into different processing center overall programme.To select a design for the directory structure of the variation machinery tools, the design of the proposed elements for a complete, structured format, a solution setdesign directory. And Set Design listed in the directory comment on each of the additional information, very beneficial to design engineers choice of the elements.According to the connectivity features of mechanical parts and components, will be summarized into four types: 1) The components of direct targeting, and self-adjustment of parts, 2) a common structure of the assembly, 3) have nested structure and inlay Shell-like components of the connection, 4) a modular architecture and modular components of the connection. And a quasi-symbols that the typical components and rules of the connection between the components, to achieve this connection between the components of the algorithm and the concept of visualization.In the mechanical system design, "features a" module on the functions of decomposition, and provides the best functional decomposition "tablets" of the extent of the functional and institutional forms of one-to-one. "Structure to establish" as a function of the module is the choice of targets in order to achieve mapping algorithm.3, based on knowledge of product design featuresKnowledge-based product design features of the main features are: to use the computer to identify the language describing the characteristics of the product design experts in the field of knowledge and experience to establish the appropriate knowledge base and reasoning machine, and then use the storage areas have been established by the knowledge and reasoning Mechanisms to achieve computer-aided design products.The mechanical system design is based on products with the characteristics, and design experts in the field of knowledge and experience to push volume and decision-making, the completion of several comprehensive. To achieve this stage of the computer-aided design, we must study the automatic acquisition of knowledge, expression, integration, coordination, management and use. To this end, the scholars at home and abroad designed for mechanical systems design knowledge of automated processing done a lot of research work, the method used can be summarized in the following few.3.1 coding methodAccording to "campaign conversion" feature (the function million) institutions will be classified, described and use the code function yuan and institutional categories, which established a "body system design expert system" Knowledge Base. On this basis, will be the dual logic and fuzzy comprehensive evaluation of combining theory, the establishment of the "expert systems" reasoning mechanism, and for thefour-position for the design of the machine.Use of biological evolution theory, through natural selection and sexual reproduction to the principle of evolution of organisms to the body design, use of network theory methods to express the structure for topology, and then through the coding technology, the structure and institutions Performance of individual chromosomes into the binary string, and in accordance with design requirements of fitness, the use of biological evolution theory of reproduction control mechanism, through the selection, crossover, such as a sudden variation means to eliminate low value of the individual are not suited to the fast evolution Be the best adaptation of the individual, that is, most with the design requirements of the agency programme.3.2 knowledge of the law mixedThe complex mechanical systems design, mixed use of the knowledge expression describes the design of various types of knowledge is particularly suited to this point has been the design of many scholars of the consensus.In the development of complex product design intelligent decision support system DMDSS, will be the rules, framework, processes and neural networks, and other knowledge that organic combination of methods to adapt to different types of knowledge in the design of the description. Knowledge will be a single expression of a variety of methods (rules, framework and process), according to object-oriented programming principles, the framework of the groove with that object's properties, with rules that target the dynamic characteristics, with the knowledge that the treatment process, group Into a hybrid form of knowledge, and successfully developed the "object-oriented NC gantry milling machine gearbox design intelligent system GBCDIS" and "transmission structure design expert system GBSDES".3.3 use of the knowledge-based development toolCoupling in the CAD system, the use of the knowledge-based development tools NEXPERT-OBJECT, through the use of object-oriented approach, to create an object-oriented database design method for coupling the designer to design and structural design Provided extensive and reliable method of the design spectrum. NEXPERT describe the use of linear guide the design of the need to design based on knowledge of the content, which seek to knowledge-based solutions, and developed a linear guide design expert system.3.4 Design Law DirectoryConstruction of the "modules", "functional element solution" and "institutions"three progressive design directory, and this directory of three progressive design principles of the programme as a mechanical transmission system intelligent design and development of the knowledge base of design Aids.3.5 Based on the example of the wayIn the development of expert systems design knowledge base, using the basic predicate described design requirements, design conditions and the selected programme, described by frame "Project" and various "concept entity," through case-based reasoning of the technologies used to produce candidate With the horsepower to product design requirements. 4, Intelligent DesignIntelligent Design is the main characteristics: According to the theories of design, through the use of 3D graphics software, intelligent design software and virtual reality technology, and multimedia, hypermedia tools for product development design, the concept of products, description of the product frame.中文译文:导言迅速发展的科学和技术,产品功能的要求日益增多和复杂性增加了预期寿命缩短,更换速度更快。
机械专业中英文对照大全 机械工程师必备
机械专业英语词汇陶瓷ceramics合成纤维synthetic fibre电化学腐蚀electrochemical corrosion 车架automotive chassis悬架suspension转向器redirector变速器speed changer板料冲压sheet metal parts孔加工spot facing machining车间workshop工程技术人员engineer气动夹紧pneuma lock数学模型mathematical model画法几何descriptive geometry机械制图Mechanical drawing投影projection视图view剖视图profile chart标准件standard component零件图part drawing装配图assembly drawing尺寸标注size marking技术要求technical requirements刚度rigidity内力internal force位移displacement截面section疲劳极限fatigue limit断裂fracture塑性变形plastic distortion脆性材料brittleness material刚度准则rigidity criterion垫圈washer垫片spacer直齿圆柱齿轮straight toothed spur gear 斜齿圆柱齿轮helical—spur gear直齿锥齿轮straight bevel gear运动简图kinematic sketch齿轮齿条pinion and rack蜗杆蜗轮worm and worm gear虚约束passive constraint曲柄crank 摇杆racker凸轮cams共轭曲线conjugate curve范成法generation method定义域definitional domain值域range导数\\微分differential coefficient求导derivation定积分definite integral不定积分indefinite integral曲率curvature偏微分partial differential毛坯rough游标卡尺slide caliper千分尺micrometer calipers攻丝tap二阶行列式second order determinant逆矩阵inverse matrix线性方程组linear equations概率probability随机变量random variable排列组合permutation and combination气体状态方程equation of state of gas动能kinetic energy势能potential energy机械能守恒conservation of mechanical energy动量momentum桁架truss轴线axes余子式cofactor逻辑电路logic circuit触发器flip—flop脉冲波形pulse shape数模digital analogy液压传动机构fluid drive mechanism机械零件mechanical parts淬火冷却quench淬火hardening回火tempering调质hardening and tempering磨粒abrasive grain结合剂bonding agent砂轮grinding wheel后角clearance angle龙门刨削planing主轴spindle主轴箱headstock卡盘chuck加工中心machining center车刀lathe tool车床lathe钻削镗削bore车削turning磨床grinder基准benchmark钳工locksmith锻forge压模stamping焊weld拉床broaching machine拉孔broaching装配assembling铸造found流体动力学fluid dynamics流体力学fluid mechanics加工machining液压hydraulic pressure切线tangent机电一体化mechanotronics mechanical-electrical integration气压air pressure pneumatic pressure稳定性stability介质medium液压驱动泵fluid clutch液压泵hydraulic pump阀门valve失效invalidation强度intensity载荷load应力stress安全系数safty factor可靠性reliability螺纹thread螺旋helix键spline销pin滚动轴承rolling bearing滑动轴承sliding bearing弹簧spring制动器arrester brake十字结联轴节crosshead联轴器coupling链chain皮带strap精加工finish machining粗加工rough machining变速箱体gearbox casing腐蚀rust氧化oxidation磨损wear耐用度durability随机信号random signal离散信号discrete signal超声传感器ultrasonic sensor集成电路integrate circuit挡板orifice plate残余应力residual stress套筒sleeve扭力torsion冷加工cold machining电动机electromotor汽缸cylinder过盈配合interference fit热加工hotwork摄像头CCD camera倒角rounding chamfer优化设计optimal design工业造型设计industrial moulding design有限元finite element滚齿hobbing插齿gear shaping伺服电机actuating motor铣床milling machine钻床drill machine镗床boring machine步进电机stepper motor丝杠screw rod导轨lead rail组件subassembly可编程序逻辑控制器Programmable Logic Controller PLC电火花加工electric spark machining电火花线切割加工electrical discharge wire —cutting相图phase diagram热处理heat treatment固态相变solid state phase changes有色金属nonferrous metal陶瓷ceramics合成纤维synthetic fibre电化学腐蚀electrochemical corrosion车架automotive chassis悬架suspension转向器redirector变速器speed changer板料冲压sheet metal parts孔加工spot facing machining车间workshop工程技术人员engineer气动夹紧pneuma lock数学模型mathematical model画法几何descriptive geometry机械制图Mechanical drawing投影projection视图view剖视图profile chart标准件standard component零件图part drawing装配图assembly drawing尺寸标注size marking技术要求technical requirements刚度rigidity内力internal force位移displacement截面section疲劳极限fatigue limit断裂fracture塑性变形plastic distortion脆性材料brittleness material刚度准则rigidity criterion垫圈washer垫片spacer直齿圆柱齿轮straight toothed spur gear斜齿圆柱齿轮helical—spur gear 直齿锥齿轮straight bevel gear运动简图kinematic sketch齿轮齿条pinion and rack蜗杆蜗轮worm and worm gear虚约束passive constraint曲柄crank摇杆racker凸轮cams共轭曲线conjugate curve范成法generation method定义域definitional domain值域range导数\\微分differential coefficient求导derivation定积分definite integral不定积分indefinite integral曲率curvature偏微分partial differential毛坯rough游标卡尺slide caliper千分尺micrometer calipers攻丝tap二阶行列式second order determinant逆矩阵inverse matrix线性方程组linear equations概率probability随机变量random variable排列组合permutation and combination气体状态方程equation of state of gas动能kinetic energy势能potential energy机械能守恒conservation of mechanical energy 动量momentum桁架truss轴线axes余子式cofactor逻辑电路logic circuit触发器flip-flop脉冲波形pulse shape数模digital analogy液压传动机构fluid drive mechanism机械零件mechanical parts淬火冷却quench淬火hardening回火tempering调质hardening and tempering磨粒abrasive grain结合剂bonding agent砂轮grinding wheelAssembly line 组装线Layout 布置图Conveyer 流水线物料板Rivet table 拉钉机Rivet gun 拉钉枪Screw driver 起子Pneumatic screw driver 气动起子worktable 工作桌OOBA 开箱检查fit together 组装在一起fasten 锁紧(螺丝)fixture 夹具(治具)pallet 栈板barcode 条码barcode scanner 条码扫描器fuse together 熔合fuse machine热熔机repair修理operator作业员QC品管supervisor 课长ME 制造工程师MT 制造生技cosmetic inspect 外观检查inner parts inspect 内部检查thumb screw 大头螺丝lbs. inch 镑、英寸EMI gasket 导电条front plate 前板rear plate 后板chassis 基座bezel panel 面板power button 电源按键reset button 重置键Hi—pot test of SPS 高源高压测试Voltage switch of SPS 电源电压接拉键sheet metal parts 冲件plastic parts 塑胶件SOP 制造作业程序material check list 物料检查表work cell 工作间trolley 台车carton 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机械设计外文翻译英文原文1概要
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 thebearings,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 ar c 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,FoshanUniversity,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 andSteelmaking2010VOL37NO3Design 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:(ibased 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(iifor settling interference of the two four-barlinkages,rigid linkages optimised in step (iare substituted by steel plate springs with elastic deformation and then form two leaf spring four-bar linkages(iiibased 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 2andC 2D 2;S is the amplitude of the mould;D Q is the swing angle of the linkage of B 1D1and 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 forexample,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(1According to Table 1,it can be seen that the design optimisation variables are x~R ,S ,h ,r ,R 1,R 2½ T(2By 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 ¡R1¡0:91R(3where 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 (2and 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 D5150mm;the guiding accuracies of two rigid four-bar linkages D R E50?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 ,rad0.050.08r ,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/Ra 5arcsin(H 2/RD Q 52arcsin(S /2l 1cos r 1D Q 52arcsin(S /2l 1cos r 1l 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 1Ec ~arccos ½(l 24z D 2E 2{C 2E 2 (2l 4:D 2Ev ~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=2 w ~arccos ½(OD 1’2z l 21{R 21.(2OD 1’:l 1w ~arccos ½(OD 2’2z l 21{R 22.(2OD 2’:l 1d 5w z c z v z bd 5w z c 2(v z bOE ’~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(4where 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 theflexible body is undeformed;and u P is the relative deflec tion 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 (4with 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(5Flexible 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(6The motion equation of flexible body is deduced from d L L: {L L z l L y T {Q ~0y ~08><>:(7where 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(8where 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(9where 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 (8and (9into 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 (10Kinematics 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 oscillationmechanism 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:(ithe vibration table is symmetric about x –y planeand direction of –y is the casting direction,with the coordinate as shown in Fig.4(iileaf 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 2D2(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 mouldare 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 Table4.Limited by space,only the first to th e 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 defle ct 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,leafspring 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 frequ encies 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 2010VOL37NO3Zhang et al. Cascaded whole-leaf spring oscillation mechanism for mould in continuous casting a leaf spring 1; b leaf spring 4; c leaf spring 2; d leaf spring 3 8 Forces applied on leaf springs at different amplitudes Forces applied on leaf springs at different amplitudes To understand the forces applied on leaf springs under different amplitudes,the motion of the mould with different lengths of the eccentric shaft respectively h53 mm and h52 mm (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, 4 and 2, 3 in a period are obtained as shown in Fig. 8. It can be seen that the forces applied on the ends of leaf springs 1 and 4 are similar and vary at nonsinusoidal 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 2 and 3 vary with the same law, yet opposite to those of leaf springs 1 and 4. When the mould is above its equilibrium position at the first half-period, leaf springs 2 and 3 bear 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 oscillation With the same frequency and amplitude in the section on ‘Kinematics simulation and results’, based on the dynamic simulations at different deflection ratios of oscillation a1510%, a2530%, a3550%, 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 o f 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 ruleto 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 ratios of a leaf spring 1; b leaf spring 2; c leaf spring 3; d leaf spring 4 9 Forces applied on leaf springs at different deflection ratio Ironmaking and Steelmaking 2010 VOL 37 NO 3 209Zhang et al. Cascaded whole-leaf spring oscillation mechanism for mould in continuous casting the force curves of leaf springs become bigger with the deflection ratio of oscillation enlarging, but the amplitudes of forces of every leaf spring are invariant. Effect of basic oscillatory parameters on joint forces The 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 oscil lation 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. 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. Outlook Such a system is now being planned for use in industry. References 1. Y. G. Yan and X. J. Wang: ‘Error analysis and comparison of two typical 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 continuous casting’, Iron Steel Eng., 1996, 7, 29–37. 4. F. Wimmer: ‘High speed billet casting: theoretical investigations and practical experience’, Proc. VAI CCC’96, Linz, Austria, May 1996, VAI, Paper 1. 5. CCTE: ‘The ca scaded whole-leaf springs oscillation device’, Chinese patent no. ZL02238393.x, February 2003. 6. R. Kohl, K. Morwald, J. Poppl and H. Thone: ‘The DYNAFLEX ¨ ¨ ¨ ¨ oscillator – 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 the series 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-bar linkage oscillation mech anism 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-joint manipulator carrying a payload with rotary inertia’, Mech. Mach. Theory, 2000, 35, 785–820. 11. B. O. Al-Bedoor and Y. A. Khulief: ‘Finite element dynamic modeling 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 in continuous casting’, 20–25; 2000, Beijing, Metallurgical Industry Press. 14. R. Shao: ‘Dynamics of mechanical system’, 30–34; 2005, Beijing, Mechanical Industry Press. Conclusions 1. 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。
Mechanical-Design机械设计毕业论文外文文献翻译及原文
毕业设计(论文)外文文献翻译文献、资料中文题目:机械设计文献、资料英文题目:Mechanical Design文献、资料来源:文献、资料发表(出版)日期:院(部):专业:班级:姓名:学号:指导教师:翻译日期: 2017.02.14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。
它是一种用来转换或传递能量的装置,例如:发动机、涡轮机、车辆、起重机、印刷机、洗衣机、照相机和摄影机等。
许多原则和设计方法不但适用于机器的设计,也适用于非机器的设计。
术语中的“机械装置设计”的含义要比“机械设计”的含义更为广泛一些,机械装置设计包括机械设计。
在分析运动及设计结构时,要把产品外型以及以后的保养也要考虑在机械设计中。
在机械工程领域中,以及其它工程领域中,所有这些都需要机械设备,比如:开关、凸轮、阀门、船舶以及搅拌机等。
关键词:设计流程设计规则机械设计设计流程设计开始之前就要想到机器的实际性,现存的机器需要在耐用性、效率、重量、速度,或者成本上得到改善。
新的机器必需具有以前机器所能执行的功能。
在设计的初始阶段,应该允许设计人员充分发挥创造性,不要受到任何约束。
即使产生了许多不切实际的想法,也会在设计的早期,即在绘制图纸之前被改正掉。
只有这样,才不致于阻断创新的思路。
通常,还要提出几套设计方案,然后加以比较。
很有可能在这个计划最后决定中,使用了某些不在计划之内的一些设想。
一般的当外型特点和组件部分的尺寸特点分析得透彻时,就可以全面的设计和分析。
接着还要客观的分析机器性能的优越性,以及它的安全、重量、耐用性,并且竞争力的成本也要考虑在分析结果之内。
每一个至关重要的部分要优化它的比例和尺寸,同时也要保持与其它组成部分相协调。
也要选择原材料和处理原材料的方法。
通过力学原理来分析和实现这些重要的特性,如那些静态反应的能量和摩擦力的最佳利用,像动力惯性、加速动力和能量;包括弹性材料的强度、应力和刚度等材料的物理特性,以及流体润滑和驱动器的流体力学。
机械设计外文翻译(中英文)
Machine design theoryThe machine design is through designs the new product or improves the old product to meet the human need the application technical science. It involves the project technology each domain, mainly studies the product the size, the shape and the detailed structure basic idea, but also must study the product the personnel which in aspect the and so on manufacture, sale and use question.Carries on each kind of machine design work to be usually called designs the 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 on mechanical drawing, kinematics, engineerig material, materials mechanics and machine manufacture technology has the deep elementary knowledge.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 not 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 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 spendsthe 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.Newly designs itself can have the question occurrence which many flaws and has not been able to expect, only has after these flaws and the question are solved, can manifest new goods come into the market the product superiority. Therefore, a performance superior product is born at the same time, also is following a higher risk. Should emphasize, if designs itself does not request to use the brand-new method, is not unnecessary merely for the goal which transform to use the new method.In 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.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. In order to carry on the effective exchange, needs to solve the following problem:(1) designs whether this product truly does need for the people? Whether there is competitive ability(2) does this product compare with other companies'' existing similar products?(3) produces this kind of product is whether economical?(4) product service is whether convenient?(5) product whether there is sale? Whether may gain?Only has the time to be able to produce the correct answer to above question. But, the product design, the manufacture and the sale only can in carry on to the above question preliminary affirmation answer foundation in. Project engineer also should through the detail drawing and the assembly drawing, carries on the consultation together with the branch of manufacture to the finally design proposal.Usually, can have some problem in the manufacture process. Possibly can request to some components size or the common difference makes some changes, causes the components the production to change easily. But, in the project change must have to pass through designs the personnel to authorize, guaranteed cannot damage the product the function. Sometimes, when in front of product assembly or in the packing foreign shipment experiment only then discovers in the design some kind of flaw. These instances exactly showed the design is a dynamic process. Always has a better method to complete the design work, designs the personnel to be supposed unceasingly diligently, seeks these better method.Recent year, the engineerig material choice already appeared importantly. In addition, the choice process should be to the material continuously the unceasing again appraisal process. The new material unceasingly appears, but some original materials can obtain the quantity possibly can reduce. The environmental pollution, material recycling aspect and so on use, worker''s health and security frequently can attach the new limiting condition to the choice of material. In order to reduce the weight or saves the energy, possibly can request the use different material. Comes from domestic and international competition, to product service maintenance convenience request enhancement and customer''s aspect the and so on feedback pressure, can urge the people to carry on to the material reappraises. Because the material does not select when created the product responsibility lawsuit, has already had the profoundinfluence. In addition, the material and between the material processing interdependence is already known by the people clearly. Therefore, in order to can and guarantees the quality in the reasonable cost under the premise to obtain satisfaction the result, project engineer makes engineers all to have earnestly carefully to choose, the determination and the use material.Makes any product the first step of work all is designs. Designs usually may divide into several explicit stages: (a) preliminary design; (b) functional design; (c) production design. In the preliminary design stage, the designer emphatically considered the product should have function. Usually must conceive and consider several plans, then decided this kind of thought is whether feasible; If is feasible, then should makes the further improvement to or several plans. In this stage, the question which only must consider about the choice of material is: Whether has the performance to conform to the request material to be possible to supply the choice; If no, whether has a bigger assurance all permits in the cost and the time in the limit develops one kind of new material.In the functional design and the engineering design stage, needs to make a practical feasible design. Must draw up the quite complete blueprint in this stage, chooses and determines each kind of components the material. Usually must make the prototype or the working model, and carries on the experiment to it, the appraisal product function, the reliability, the outward appearance and the service maintenance and so on. Although this kind of experiment possibly can indicate, enters in the product to the production base in front of, should replace certain materials, but, absolutely cannot this point take not earnestly chooses the material the excuse. Should unify the product the function, earnestly carefully considers the product the outward appearance, the cost and the reliability. Has the achievement very much the company when manufacture all prototypes, selects the material should the material which uses with its production in be same, and uses the similar manufacture technology as far as possible. Like this has the advantage very much to the company. The function complete prototype if cannot act according to the anticipated sales volume economically to make, or is prototypical and the official production installment has in the quality and the reliable aspect is very greatly different, then this kind of prototypedoes not have the great value. Project engineer is best can completely complete the material in this stage the analysis, the choice and the determination work, but is not remains it to the production design stage does. Because, is carries on in the production design stage material replacement by other people, these people are inferior to project engineer to the product all functions understanding. In the production design stage, is should completely determine with the material related main question the material, causes them to adapt with the existing equipment, can use the existing equipment economically to carry on the processing, moreover the material quantity can quite be easy to guarantee the supply.In the manufacture process, inevitably can appear to uses the material to make some changes the situation. The experience indicated that, may use certain cheap materials to take the substitute. However, in the majority situation, in will carry on the production later to change the material to have in to start before the production to change the price which the material will spend to have to be higher than. Completes the choice of material work in the design stage, may avoid the most such situations. Started after the production manufacture to appear has been possible to supply the use the new material is replaces the material the most common reason. Certainly, these new materials possibly reduce the cost, the improvement product performance. But, must carry on the earnest appraisal to the new material, guarantees its all performance all to answer the purpose. Must remember that, the new material performance and the reliable very few pictures materials on hand such understood for the people. The majority of products expiration and the product accident caused by negligence case is because in selects the new material to take in front of substitution material, not truly understood their long-term operational performance causes.The product responsibility lawsuit forces designs the personnel and the company when the choice material, uses the best procedure. In the material process, five most common questions are: (a) did not understand or cannot use about the material application aspect most newly the best information paper; (b) has not been able to foresee and to consider the dusk year possible reasonable use (for example to have the possibility, designs the personnel also to be supposed further to forecast and the consideration because product application method not when creates consequence.ecent years many products responsibilities lawsuit case, because wrongly uses theplaintiff which the product receives the injury to accuse produces the factory, and wins the decision); (c) uses the material data not entire perhaps some data are indefinite, works as its long-term performance data is the like this time in particular;(d) the quality control method is not suitable and not after the confirmation; (e) the personnel which completely is not competent for the post by some chooses the material.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 thebasic understanding.翻译:机械设计理论机械设计,通过设计新产品或改进老产品,以满足人类需要的应用技术科学。
机械类外文翻译-机械设计译文
机械工程摄政出版公司,1998机械设计查尔斯.比尔兹利摘要:机器是机构与其他零件的组合,为了有益的用途而转换、传递或利用能量、力或者运动实例有发动机、涡轮、车辆、卷扬机、印刷机、洗衣机和电影摄影机.许多适用于机器设计的原理和力法也适用于不是真正机器的制成品,从轮毂盖和档案橱柜到仪表和核压力容器。
“机械设计”这一术语比“机器设计”更为广义,它包括机器设计。
而对于某些仪器,如用以确定热、流动线路和体积的热力以及流体方面的问题要单独考虑。
但是,在机械设计时要考虑运动和结构方面的问题以及保存和封装的规定。
在机械工程领域以及其他工程领域应用机械设计,都需要诸如开关、凸轮、阀门、容器和搅拌器等机械装置。
关键字:机械设计、机构设计,工程工差设计过程设计开始于一种真实的或想像的需要。
现有的仪器需要在耐用性、效率、重量、速度或成本上有所改善。
新的工具也许要用来做那些以前需要人来完成的工作,例如计算、汇编或服务。
整体宗旨或部分定义,设计的下一个步骤是机制的构想和一些必要职能的安排。
对于此,徒手画图是很重要的,不仅作为一个人的想法而纪录,而且可以在与别人的讨论中作为一种援助,但是最重要的是与自己的思想交流,充当一种创造性思维的兴奋剂。
并且,由于一种新的机器通常包含一些知名的构件类型的新的组装或替代,也或许是在大小上和材料上有所改变,因此,丰富的组件知识是十分有用的。
无论是在设计的过程中或之后,设计师都要做快速或粗略的计算与分析,以确定此项设计的整体大小和可行性。
当获得一些所需要的或可用的相关空间量时,规模布局图就可以做了。
当机器的几个组成部分的基本形状和一些尺寸规格都确定时,认真分析就可以开始了。
分析将主要围绕该机器的客观满意度和性能优越性展开,并要增加安全性和保证耐用性的同时降低机器重量,还要研究确定每个受重载的构件的尺寸,连同这些构件之间的受力平衡。
材料和加工工艺也要选择。
这些重要目标的实现必须依靠基于力学原理的分析,例如那些静态反作用力和摩擦力的最佳利用,动力学中的惯性力、加速度和功,弹性材料的强度、应力和挠度,材料的物理特性,水力驱动器的润滑和流体力学。
机械类外文文献翻译(中英文翻译)
机械类外文文献翻译(中英文翻译)英文原文Mechanical Design and Manufacturing ProcessesMechanical design is the application of science and technology to devise new or improved products for the purpose of satisfying human needs. It is a vast field of engineering technology which not only concerns itself with the original conception of the product in terms of its size, shape and construction details, but also considers the various factors involved in the manufacture, marketing and use of the product.People who perform the various functions of mechanical design are typically called designers, or design engineers. Mechanical design is basically a creative activity. However, in addition to being innovative, a design engineer must also have a solid background in the areas of mechanical drawing, kinematics, dynamics, materials engineering, strength of materials and manufacturing processes.As stated previously, the purpose of mechanical design is to produce a product which will serve a need for man. Inventions, discoveries and scientific knowledge by themselves do not necessarily benefit people; only if they are incorporated into a designed product will a benefit be derived. It should be recognized, therefore, that a human need must be identified before a particular product is designed.Mechanical design should be considered to be an opportunity to use innovative talents to envision a design of a product, to analyze the systemand then make sound judgments on how the product is to be manufactured. It is important to understand the fundamentals of engineering rather than memorize mere facts and equations. There are no facts or equations which alone can be used to provide all the correct decisions required to produce a good design.On the other hand, any calculations made must be done with the utmost care and precision. For example, if a decimal point is misplaced, an otherwise acceptable design may not function.Good designs require trying new ideas and being willing to take a certain amount of risk, knowing that if the new idea does not work the existing method can be reinstated. Thus a designer must have patience, since there is no assurance of success for the time and effort expended. Creating a completely new design generally requires that many old and well-established methods be thrust aside. This is not easy since many people cling to familiar ideas, techniques and attitudes. A design engineer should constantly search for ways to improve an existing product and must decide what old, proven concepts should be used and what new, untried ideas should be incorporated.New designs generally have "bugs" or unforeseen problems which must be worked out before the superior characteristics of the new designs can be enjoyed. Thus there is a chance for a superior product, but only at higher risk. It should be emphasized that, if a design does not warrant radical new methods, such methods should not be applied merely for the sake of change.During the beginning stages of design, creativity should be allowedto flourish without a great number of constraints. Even though many impractical ideas may arise, it is usually easy to eliminate them in the early stages of design before firm details are required by manufacturing. In this way, innovative ideas are not inhibited. Quite often, more than one design is developed, up to the point where they can be compared against each other. It is entirely possible that the design which is ultimately accepted will use ideas existing in one of the rejected designs that did not show as much overall promise.Psychologists frequently talk about trying to fit people to the machines they operate. It is essentially the responsibility of the design engineer to strive to fit machines to people. This is not an easy task, since there is really no average person for which certain operating dimensions and procedures are optimum.Another important point which should be recognized is that a design engineer must be able to communicate ideas to other people if they are to be incorporated. Communicating the design to others is the final, vital step in the design process. Undoubtedly many great designs, inventions, and creative works have been lost to mankind simply because the originators were unable or unwilling to explain their accomplishments to others. Presentation is a selling job. The engineer, when presenting a new solution to administrative, management, or supervisory persons, is attempting to sell or to prove to them that this solution is a better one. Unless this can be done successfully, the time and effort spent on obtaining the solution have been largely wasted.Basically, there are only three means of communication available tous. These are the written, the oral, and the graphical forms. Therefore the successful engineer will be technically competent and versatile in all three forms of communication. A technically competent person who lacks ability in any one of these forms is severely handicapped. If ability in all three forms is lacking, no one will ever know how competent that person is!The competent engineer should not be afraid of the possibility of not succeeding in a presentation. In fact, occasional failure should be expected because failure or criticism seems to accompany every really creative idea. There is a great deal to be learned from a failure, and the greatest gains are obtained by those willing to risk defeat. In the final analysis, the real failure would lie in deciding not to make the presentation at all. To communicate effectively, the following questions must be answered:(1) Does the design really serve a human need?(2) Will it be competitive with existing products of rival companies?(3) Is it economical to produce?(4) Can it be readily maintained?(5) Will it sell and make a profit?Only time will provide the true answers to the preceding questions, but the product should be designed, manufactured and marketed only with initial affirmative answers. The design engineer also must communicate the finalized design to manufacturing through the use of detail and assembly drawings.Quite often, a problem will occur during the manufacturing cycle [3].It may be that a change is required in the dimensioning or tolerancing of a part so that it can be more readily produced. This fails in the category of engineering changes which must be approved by the design engineer so that the product function will not be adversely affected. In other cases, a deficiency in the design may appear during assembly or testing just prior to shipping. These realities simply bear out the fact that design is a living process. There is always a better way to do it and the designer should constantly strive towards finding that better way.Designing starts with a need, real or imagined. Existing apparatus may need improvements in durability, efficiently, weight, speed, or cost. New apparatus may be needed to perform a function previously done by men, such as computation, assembly, or servicing. With the objective wholly or partly defined, the next step in design is the conception of mechanisms and their arrangements that will perform the needed functions.For this, freehand sketching is of great value, not only as a record of one's thoughts and as an aid in discussion with others, but particularly for communication with one's own mind, as a stimulant for creative ideas.When the general shape and a few dimensions of the several components become apparent, 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 east. Optimum proportions and dimensions will be sought for each critically loaded section, together with a balance between the strength of the several components. Materials and their treatment will be chosen. These important objectives can be attained only by analysis based upon the principles ofmechanics, such as those of statics for reaction forces and for the optimumutilization of friction; of dynamics for inertia, acceleration, and energy; of elasticity and strength of materials for stress。
机械专业中英文对照大全 机械工程师必备
机械专业英语词汇陶瓷ceramics合成纤维synthetic fibre电化学腐蚀electrochemical corrosion 车架automotive chassis悬架suspension转向器redirector变速器speed changer板料冲压sheet metal parts孔加工spot facing machining车间workshop工程技术人员engineer气动夹紧pneuma lock数学模型mathematical model画法几何descriptive geometry机械制图Mechanical drawing投影projection视图view剖视图profile chart标准件standard component零件图part drawing装配图assembly drawing尺寸标注size marking技术要求technical requirements刚度rigidity内力internal force位移displacement截面section疲劳极限fatigue limit断裂fracture塑性变形plastic distortion脆性材料brittleness material刚度准则rigidity criterion垫圈washer垫片spacer直齿圆柱齿轮straight toothed spur gear 斜齿圆柱齿轮helical-spur gear直齿锥齿轮straight bevel gear运动简图kinematic sketch齿轮齿条pinion and rack蜗杆蜗轮worm and worm gear虚约束passive constraint曲柄crank 摇杆racker凸轮cams共轭曲线conjugate curve范成法generation method定义域definitional domain值域range导数\\微分differential coefficient求导derivation定积分definite integral不定积分indefinite integral曲率curvature偏微分partial differential毛坯rough游标卡尺slide caliper千分尺micrometer calipers攻丝tap二阶行列式second order determinant逆矩阵inverse matrix线性方程组linear equations概率probability随机变量random variable排列组合permutation and combination气体状态方程equation of state of gas动能kinetic energy势能potential energy机械能守恒conservation of mechanical energy动量momentum桁架truss轴线axes余子式cofactor逻辑电路logic circuit触发器flip-flop脉冲波形pulse shape数模digital analogy液压传动机构fluid drive mechanism机械零件mechanical parts淬火冷却quench淬火hardening回火tempering调质hardening and tempering磨粒abrasive grain结合剂bonding agent砂轮grinding wheel后角clearance angle龙门刨削planing主轴spindle主轴箱headstock卡盘chuck加工中心machining center车刀lathe tool车床lathe钻削镗削bore车削turning磨床grinder基准benchmark钳工locksmith锻forge压模stamping焊weld拉床broaching machine拉孔broaching装配assembling铸造found流体动力学fluid dynamics流体力学fluid mechanics加工machining液压hydraulic pressure切线tangent机电一体化mechanotronics mechanical—electrical integration气压air pressure pneumatic pressure稳定性stability介质medium液压驱动泵fluid clutch液压泵hydraulic pump阀门valve失效invalidation强度intensity载荷load应力stress安全系数safty factor可靠性reliability螺纹thread螺旋helix键spline销pin滚动轴承rolling bearing滑动轴承sliding bearing弹簧spring制动器arrester brake十字结联轴节crosshead联轴器coupling链chain皮带strap精加工finish machining粗加工rough machining变速箱体gearbox casing腐蚀rust氧化oxidation磨损wear耐用度durability随机信号random signal离散信号discrete signal超声传感器ultrasonic sensor集成电路integrate circuit挡板orifice plate残余应力residual stress套筒sleeve扭力torsion冷加工cold machining电动机electromotor汽缸cylinder过盈配合interference fit热加工hotwork摄像头CCD camera倒角rounding chamfer优化设计optimal design工业造型设计industrial moulding design有限元finite element滚齿hobbing插齿gear shaping伺服电机actuating motor铣床milling machine钻床drill machine镗床boring machine步进电机stepper motor丝杠screw rod导轨lead rail组件subassembly可编程序逻辑控制器Programmable Logic Controller PLC电火花加工electric spark machining电火花线切割加工electrical discharge wire - cutting 相图phase diagram热处理heat treatment固态相变solid state phase changes有色金属nonferrous metal陶瓷ceramics合成纤维synthetic fibre电化学腐蚀electrochemical corrosion车架automotive chassis悬架suspension转向器redirector变速器speed changer板料冲压sheet metal parts孔加工spot facing machining车间workshop工程技术人员engineer气动夹紧pneuma lock数学模型mathematical model画法几何descriptive geometry机械制图Mechanical drawing投影projection视图view剖视图profile chart标准件standard component零件图part drawing装配图assembly drawing尺寸标注size marking技术要求technical requirements刚度rigidity内力internal force位移displacement截面section疲劳极限fatigue limit断裂fracture塑性变形plastic distortion脆性材料brittleness material刚度准则rigidity criterion垫圈washer垫片spacer直齿圆柱齿轮straight toothed spur gear斜齿圆柱齿轮helical—spur gear直齿锥齿轮straight bevel gear 运动简图kinematic sketch齿轮齿条pinion and rack蜗杆蜗轮worm and worm gear虚约束passive constraint曲柄crank摇杆racker凸轮cams共轭曲线conjugate curve范成法generation method定义域definitional domain值域range导数\\微分differential coefficient求导derivation定积分definite integral不定积分indefinite integral曲率curvature偏微分partial differential毛坯rough游标卡尺slide caliper千分尺micrometer calipers攻丝tap二阶行列式second order determinant逆矩阵inverse matrix线性方程组linear equations概率probability随机变量random variable排列组合permutation and combination气体状态方程equation of state of gas动能kinetic energy势能potential energy机械能守恒conservation of mechanical energy 动量momentum桁架truss轴线axes余子式cofactor逻辑电路logic circuit触发器flip-flop脉冲波形pulse shape数模digital analogy液压传动机构fluid drive mechanism机械零件mechanical parts淬火冷却quench淬火hardening回火tempering调质hardening and tempering磨粒abrasive grain结合剂bonding agent砂轮grinding wheelAssembly line 组装线Layout 布置图Conveyer 流水线物料板Rivet table 拉钉机Rivet gun 拉钉枪Screw driver 起子Pneumatic screw driver 气动起子worktable 工作桌OOBA 开箱检查fit together 组装在一起fasten 锁紧(螺丝)fixture 夹具(治具)pallet 栈板barcode 条码barcode scanner 条码扫描器fuse together 熔合fuse machine热熔机repair修理operator作业员QC品管supervisor 课长ME 制造工程师MT 制造生技cosmetic inspect 外观检查inner parts inspect 内部检查thumb screw 大头螺丝lbs。
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Design of machine and machine elementsMachine designMachine design is the art of planning or devising new or improved machines to accomplish specific purposes. In general, a machine will consist of a combination of several different mechanical elements properly designed and arranged to work together, as a whole. During the initial planning of a machine, fundamental decisions must be made concerning loading, type of kinematic elements to be used, and correct utilization of the properties of engineering materials. Economic considerations are usually of prime importance when the design of new machinery is undertaken. In general, the lowest over-all costs are designed. Consideration should be given not only to the cost of design, manufacture the necessary safety features and be of pleasing external appearance. The objective is to produce a machine which is not only sufficiently rugged to function properly for a reasonable life, but is at the same time cheap enough to be economically feasible.The engineer in charge of the design of a machine should not only have adequate technical training, but must be a man of sound judgment and wide experience, qualities which are usually acquired only after considerable time has been spent in actual professional work.Design of machine elementsThe principles of design are, of course, universal. The same theory or equations may be applied to a very small part, as in an instrument, or, to a larger but similar part used in a piece of heavy equipment. In no ease, however, should mathematical calculations be looked upon as absolute and final. They are all subject to the accuracy of the various assumptions, which must necessarily be made in engineering work. Sometimes only a portion of the total number of parts in a machine are designed on the basis of analytic calculations. The form and size of the remaining parts are designed on the basis of analytic calculations. On the other hand, if the machine is very expensive, or if weight is a factor, as in airplanes, design computations may then be made for almost all the parts.The purpose of the design calculations is, of course, to attempt to predict the stress or deformation in the part in order that it may sagely carry the loads, which will be imposed on it, and that it may last for the expected life of the machine. All calculations are, of course, dependent on the physical properties of the construction materials as determined by laboratory tests. A rational method of design attempts to take the results of relatively simple and fundamental tests such as tension, compression, torsion, and fatigue and apply them to all the complicated and involved situations encountered in present-day machinery.In addition, it has been amply proved that such details as surface condition, fillets, notches, manufacturing tolerances, and heat treatment have a market effect on the strength and useful life of a machine part. The design and drafting departments must specify completely all such particulars, must specify completely all such particulars, and thus exercise the necessary close control over the finished product.As mentioned above, machine design is a vast field of engineering technology. As such, it begins with the conception of an idea and follows through the various phases of design analysis, manufacturing, marketing and consumerism. The following is a list of the major areas of consideration in the general field of machine design:①Initial design conception;②Strength analysis;③Materials selection;④Appearance;⑤Manufacturing;⑥Safety;⑦Environment effects;⑨Reliability and life;Strength is a measure of the ability to resist, without fails, forces which cause stresses and strains. The forces may be;①Gradually applied;②Suddenly applied;③Applied under impact;④Applied with continuous direction reversals;⑤Applied at low or elevated temperatures.If a critical part of a machine fails, the whole machine must be shut down until a repair is made. Thus, when designing a new machine, it is extremely important that critical parts be made strong enough to prevent failure. The designer should determine as precisely as possible the nature, magnitude, direction and point of application of all forces. Machine design is mot, however, an exact science and it is, therefore, rarely possible to determine exactly all the applied forces. In addition, different samples of a specified material will exhibit somewhat different abilities to resist loads, temperatures and other environment conditions. In spite of this, design calculations based on appropriate assumptions are invaluable in the proper design of machine.Moreover, it is absolutely essential that a design engineer knows how and why parts fail so that reliable machines which require minimum maintenance can be designed. Sometimes, a failure can be serious, such as when a tire blows out on an automobile traveling at high speeds. On the other hand, a failure may be no more than a nuisance. An example is the loosening of the radiator hose in the automobile cooling system. The consequence of this latter failure is usually the loss of some radiator coolant, a condition which is readily detected and corrected.The type of load a part absorbs is just as significant as the magnitude. Generally speaking, dynamic loads with direction reversals cause greater difficulties than static loads and, therefore, fatigue strength must be considered. Another concern is whether the material is ductile or brittle. For example, brittle materials are considered to be unacceptable where fatigue is involved.In general, the design engineer must consider all possible modes of failure, which include the following:①Stress;②Deformation;③Wear;④Corrosion;⑤Vibration;⑥Environmental damage;⑦Loosening of fastening devices.The part sizes and shapes selected must also take into account many dimensional factors which produce external load effects such as geometric discontinuities, residual stresses due to forming of desired contours, and the application of interference fit joint.Selected from” design of machine elements”, 6th edition, m. f. sports, prentice-hall, inc., 1985 and “machine design”, Anthony Esposito, charles e., Merrill publishing company, 1975.Mechanical properties of materialsThe material properties can be classified into three major headings: (1) physical, (2) chemical, (3) mechanicalPhysical propertiesDensity or specific gravity, moisture content, etc., can be classified under this category.Chemical propertiesMany chemical properties come under this category. These include acidity or alkalinity, react6ivity and corrosion. The most important of these is corrosion which can be explained in layman’s terms as the resistance of the material to decay while in continuous use in a particular atmosphere.Mechanical propertiesMechanical properties include in the strength properties like tensile, compression, shear, torsion, impact, fatigue and creep. The tensile strength of a material is obtained by dividing the maximum load, which the specimen bears by the area of cross-section of the specimen.This is a curve plotted between the stress along the This is a curve plotted between the stress along the Y-axis(ordinate) and the strain along the X-axis(abscissa) in a tensile test. A material tends to change or changes its dimensions when it is loaded, depending upon the magnitude of the load. When the load is removed it can be seen that the deformation disappears. For many materials this occurs op to a certain value of the stress called the elastic limit Ap. This is depicted by the straight line relationship and a small deviation thereafter, in the stress-strain curve (fig.3.1). Within the elastic range, the limiting value of the stress up to which the stress and strain are proportional, is called the limit of proportionality Ap. In this region, the metal obeys hookes’s law, which states that the stress is proportional to strain in the elastic range of loading, (the material completely regains its original dimensions after the load is removed). In the actual plotting of the curve, the proportionality limit is obtained at a slightly lower value of the load than theelastic limit. This may be attributed to the time-lagin the regaining of the original dimensions of the material. This effect is very frequently noticed in some non-ferrous metals.Which iron and nickel exhibit clear ranges of elasticity, copper, zinc, tin, are found to be imperfectly elastic even at relatively low values low values of stresses. Actually the elastic limit is distinguishable from the proportionality limit more clearly depending upon the sensitivity of the measuring instrument.When the load is increased beyond the elastic limit, plastic deformation starts. Simultaneously the specimen gets work-hardened. A point is reached when the deformation starts to occur more rapidly than the increasing load. This point is called they yield point Q. the metal which was resisting the load till then, starts to deform somewhat rapidly, i. e., yield. The yield stress is called yield limit Ay. The elongation of the specimen continues from Q to S and then to T. The stress-strain relation in this plastic flow period is indicated by the portion QRST of the curve. At the specimen breaks, and this load is called the breaking load. The value of the maximum load S divided by the original cross-sectional area of the specimen is referred to as the ultimate tensile strength of the metal or simply the tensile strength Au.Logically speaking, once the elastic limit is exceeded, the metal should start to yield, and finally break, without any increase in the value of stress. But the curve records an increased stress even after the elastic limit is exceeded. Two reasons can be given for this behavior:①The strain hardening of the material;②The diminishing cross-sectional area of the specimen, suffered on account of the plastic deformation.The more plastic deformation the metal undergoes, the harder it becomes, due to work-hardening. The more the metal gets elongated the more its diameter (and hence, cross-sectional area) is decreased. This continues until the point S is reached.After S, the rate at which the reduction in area takes place, exceeds the rate at which the stress increases. Strain becomes so high that the reduction in area begins to produce a localized effect at some point. This is called necking. Reduction in cross-sectional area takes place very rapidly; so rapidly that the load value actually drops. This is indicated by ST. failure occurs at this point T. Then percentage elongation A and reduction in reduction in area W indicate the ductility or plasticity of the material:A=(L-L0)/L0*100%W=(A0-A)/A0*100%Where L0 and L are the original and the final length of the specimen; A0 and A are the original and the final cross-section area.Selected from “testing of metallic materials”Quality assurance and controlProduct quality is of paramount importance in manufacturing. If quality is allowed deteriorate, then a manufacturer will soon find sales dropping off followed by a possible business failure. Customers expect quality in the products they buy, and if a manufacturer expects to establish and maintain a name in the business, quality control and assurance functions must be established and maintained before, throughout, and after the production process. Generally speaking, quality assurance encompasses all activities aimed at maintaining quality, including quality control. Quality assurance can be divided into three major areas. These include the following:①Source and receiving inspection before manufacturing;②In-process quality control during manufacturing;③Quality assurance after manufacturing.Quality control after manufacture includes warranties and product service extended to the users of the product.Source and receiving inspection before manufacturingQuality assurance often begins ling before any actual manufacturing takes place. This may be done through source inspections conducted at the plants that supply materials, discrete parts, or subassemblies to manufacturer. The manufacturer’s source inspector travels to the supplier factory and inspects raw material or premanufactured parts and assemblies. Source inspections present an opportunity for the manufacturer to sort out and reject raw materials or parts before they are shipped to the manufacturer’s production facility.The responsibility of the source inspector is to check materials and parts against design specifications and to reject the item if specifications are not met. Source inspections may include many of the same inspections that will be usedduring production. Included in these are:①Visual inspection;②Metallurgical testing;③Dimensional inspection;④Destructive and nondestructive inspection;⑤Performance inspection.Visual inspectionsVisual inspections examine a product or material for such specifications as color, texture, surface finish, or overall appearance of an assembly to determine if there are any obvious deletions of major parts or hardware.Metallurgical testingMetallurgical testing is often an important part of source inspection, especiallyif the primary raw material for manufacturing is stock metal such as bar stock or structural materials. Metals testing can involve all the major types of inspections including visual, chemical, spectrographic, and mechanical, which include hardness, tensile, shear, compression, and spectr5ographic analysis for alloy content. Metallurgical testing can be either destructive or nondestructive. Dimensional inspectionFew areas of quality control are as important in manufactured products as dimensional requirements. Dimensions are as important in source inspection as they are in the manufacturing process. This is especially critical if the source supplies parts for an assembly. Dimensions are inspected at the source factory using standard measuring tools plus special fit, form, and function gages that may required. Meeting dimensional specifications is critical to interchangeabilityof manufactured parts and to the successful assembly of many parts into complex assemblies such as autos, ships, aircraft, and other multipart products. Destructive and nondestructive inspectionIn some cases it may be necessary for the source inspections to call for destructive or nondestructive tests on raw materials or p0arts and assemblies. This is particularly true when large amounts of stock raw materials are involved.For example it may be necessary to inspect castings for flaws by radiographic, magnetic particle, or dye penetrant techniques before they are shipped to the manufacturer for final machining. Specifications calling for burn-in time for electronics or endurance run tests for mechanical components are further examples of nondestructive tests.It is sometimes necessary to test material and parts to destruction, but because of the costs and time involved destructive testing is avoided whenever possible. Examples include pressure tests to determine if safety factors are adequate in the design. Destructive tests are probably more frequent in the testing of prototype designs than in routine inspection of raw material or parts. Once design specifications are known to be met in regard to the strength of materials, it is often not necessary to test further parts to destruction unless they are genuinely suspect.Performance inspectionPerformance inspections involve checking the function of assemblies, especially those of complex mechanical systems, prior to installation in other products. Examples include electronic equipment subcomponents, aircraft and auto engines, pumps, valves, and other mechanical systems requiring performance evaluation prior to their shipment and final installation.Selected form “modern materials and manufacturing process”Electro-hydraulic drum brakesApplicationThe YWW series electro-hydraulic brake is a normally closed brake, suitable for horizontal mounting. It is mainly used in portal cranes, bucket stacker/reclaimers’slewing mechanism.The YKW series electro-hydraulic brake is a normally opened brake, suitable for horizontal mounting, employing a thruster as actuator. with the foot controlling switch the operator can release or close the brake. It is mainly used for deceleration braking of portal cranes’slewing mechanism. In a non-operating state the machinery can be braked by a manual close device.The RKW series brake is a normally opened brake, which is operated by foot driven hydraulic pump, suitable for horizontal mounting. Mainly used in the slewing mechanism of middle and small portal cranes. When needed, the brakeis activated by a manual closed device.Main design featuresInterlocking shoes balancing devices (patented technology) constantly equalizes the clearance of brake shoes on both sides and made adjustment unnecessary, thus avoiding one side of the brake lining sticking to the brake wheel. The brake is equipped with a shoed autoaligning device.Main hinge points are equipped with self-lubricating bearing, making high efficiency of transmission, long service life. Lubricating is unnecessary during operation.Adjustable bracket ensure the brake works well.The brake spring is arranged inside a square tube and a surveyor’s rod is placed on one side. It is easy to read braking torque value and avoid measuring and computing.Brake lining is of card whole-piece shaping structure, easy to replace. Brake linings of various materials such as half-metal (non-asbestos) hard and half-hard, soft (including asbestos) substance are available for customers to choose.All adopt the company’s new types of thruster as corollary equipment which work accurately and have long life.Hydraulic Power TransmissionThe Two Types Of Power TransmissionIn hydraulic power transmission the apparatus (pump) used for conversion of the mechanical (or electrical,thermal) energy to hydraulic energy is arranged on the input of the kinematic chain ,and the apparatus (motor) used for conversion of the hydraulic energy to mechanical energy is arranged on the output (fig.2-1)The theoretical design of the energy converters depends on the component of the bernouilli equation to be used for hydraulic power transmission.In systerms where, mainly, hydrostatic pressure is utilized, displacement(hydrostatic) pumps and motors are used, while in those where the hydrodynamic pressure is utilized is utilized gor power transmission hydrodynamic energy converters (e.g. centrifugal pumps) are used.The specific characteristic of the energy converters is the weight required for transmission of unit power. It can be demonstrated that the use of hydrostatic energy converters for the low and medium powers, and of hydrodynamic energy converters of high power are more favorite (fig.2-2). This is the main reason why hydrostatic energy converters are used in industrial apparatus. transformation of the energy in hydraulic transmission.1.driving motor (electric, diesel engine);2.mechanical energy;3.pump;4.hydraulic energy;5.hydraulic motor;6.mechanical energy;7.load variation of the mass per unit power in hydrostatic and hydrodynamic energyconverters1、hydrostatic; 2.hydrodynamicOnly displacement energy converters are dealt with in the following. The elements performing converters provide one or several size. Expansion of the working chambers in a pump is produced by the external energy admitted, and in the motor by the hydraulic energy. Inflow of the fluid occurs during expansion of the working chamber, while the outflow (displacement) is realized during contraction.Such devices are usually called displacement energy converters.The Hydrostatic PowerIn order to have a fluid of volume V1 flowing in a vessel at pressure work spent on compression W1 and transfer of the process, let us imagine a piston mechanism (fig.2-3(a)) which may be connected with the aid of valves Z0 and Z1 to the external medium under pressure P0 and reservoir of pressure p1.in the upper position of the piston (x=x0) with Z0 open the cylinder chamber is filled with fluid of volume V0and pressure P0. now shut the value Z0 and start the piston moving downwards. If Z1 is shut the fluid volume in position X=X1 of the piston decreases from V0 to V1, while the pressure rises to P1. the external work required for actuation of the piston (assuming isothermal change) isW1=-∫0x0(P-P0)Adx=-∫v1v0(P-P0)dvSelect from Hydraulic Power Transmission机器和机器零件的设计机器设计机器设计为了特定的目的而发明或改进机器的一种艺术。