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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

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

机械设计过程外文文献翻译、中英文翻译

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,。

机械设计中英文外文翻译文献

机械设计中英文外文翻译文献

中英文资料外文翻译Fundamentals Of Machinery DesignThis introductory chapter is a general survey of machinery design.First it presents the definition and major role of machinery design,the relationship between machinery and its components.Then it gives an overview of machinery design as a fundamental course and outlines a general procedure of machinery design followed by all the engineers.Finally, it lists the contents of the course and the primary goals to be achieved.1.1 The role of machinery designMachinery design is to formulate all engineering plan.Engineering in essence is to utilize the existing resources and natural law to benefit humanity.As a major segment of engineerin,machinery design involves a range of disciplines in materials,mechanics,heat,flow,control,electronics and production.Although many hightechnologies are computerized and automated,and are rapidly merged into Our daily life,machines are indispensable for various special work that is difficult or impracticable to be carried out by human.Moreover,machinery can significantly improve efficiency and quality of production,which is crucial in current competitive global market.In the modern industrialized world,the wealth and living standards of a nation are closely linked with their capabilities to design and manufacture engineering products.It can be claimed that the advancement of machinery design and manufacturing can remarkable promote the overall level of a country’s industrialization.Those nations,who do not perform well in design and manufacture fields,are not competitive in world markets.It is evident that several countries thatused to be leaders in the design and manufacturing sectors until the l 960s and the1 970s had,by the l990s,slipped back and lost their leadership.On the contrary, our Country is rapidly picking up her position in manufacturing industry since the l 9 80s and is playing a more and more vital role in the global market.To accelerate such an industrializing process of our country, highly skilled design engineers having extensiveknowledge and expertise are needed.That is why the course of machinery design is of great significance for students of engineering.The course of machinery design is considerable different from those background subjects in science and mathematics.For many students,it is perhaps one of their basic professional engineering courses concerned with obtaining solutions to practical problem s.Definitely these solutions must clearly represent an understanding of the underlying science,usually such an understanding may not be sufficient,empirical knowledge or engineering judgement has to be also involved.Furthermore,due to be professional nature of this subject,most design problems may not have one right solution.Nevertheless it is achievable to determine a better design from all feasible solutions.1.2 Machinery and componentsA state-of-the-art machine may encompass all or part of mechanical,electrical,control,sensor,monitoring and lubricating sub—systems.In termsof the functions of those parts,the machine can also be viewed to be comprised of power,transmission,execution and control/manipulation parts.Regardless of the complexity, however,the major functional part may be still the mechanical system.Forconvenience of analysis,the mechanical system can be decomposed int0.mechanisms that are designed to execute some specific tasks.And the mechanism can be further decomposed into mechanical components.In this sense,the mechanical components are the fundamental elements of machinery.On the whole,mechanical components can be classified as universal and special components.Bolts,gear and chains are the typical examples of the universal components which can be used extensively in different machines across various industrial sectors.Turbine blades,crankshaft and aircraft propeller are the examples ofthe special components,which Can be used extensively in different machines across various industrial sectors.turbine blades,crankshaft and aircraft propeller arethe examples of the special components,which are designed for some specific purposes.In addition to this,if a number of components are manufactured,assembled and even equipped as an individual system,e.g.leaf spring setin a vehicle,it is also termed as a mechanical part.A good machine definitely requires quality individual components.Thus,the design of components is very important.When designing a machine,on the otherhand,engineers invariably find that requirements and constraints of its components areinterrelated.As a local portion,the component is expected to play a certain role on the machine and therefore must be appropriately restrained by the whole system.The design of a gear drive in a speed—reducer,for instance,depends upon not only the strength and stiffness,but also the space available for the gears in the shaft and relation with other transmission drive.This means that the design of the mechanical components inevitably requires a whole view in the whole system.Due to relationship between a machine and its components,the process of machinery design usually covers interconnected designs of machine,parts,and components.Any modification and adjustment in one component may considerably affect the designs of other components or parts.To present the best possible design solution,the iteration of evaluation,analysis and optimization across all the process seem indispensable.1.3 Overview of machinery designThis course is primarily concerned with the design of specific components of machines or mechanical systems.Competence in this area is basic to the consideration and synthesis of complete machines and systems in subsequent courses and professional practice.It Can be seen that even the design of a single bolt or spring needs the designer’s thorough understanding of the principles and methods of machinery design together with empirical information,good judgment and even a degre3e of ingenuity in order to produce the best product for the society today.It is natural that designing engineers give first consideration to the functional and economic aspects of new products or devices.Machinery design needs to ensure safetyand reliability in a prescribed lifetime.To address such a problem conventionally,the technical consideration of the mechanical component design is largely centered around two main areas of concerns:(1) strength-stiffness-stability criteria involving the bulk of a solid member and (2) surface phenomena including friction,lubrication,weal7,and environmental deterioration.However,in comparison with such relatively straightforward computations as stress and deflection,the design determination of safety and reliability is likely to be an elusive and indefinite matter,complicated by psychological and sociological factors.It must be kept in mind that safety and reliability are inherently relative to each other,and the value judgmentsmust be made with regard to trade—offs between safety,reliability,cost,weight,and soforth.On the other hand,a practical design needs to reflect clearly manufacturability and economy to make sure of the lowest cost as well as the least consumption of energy and materials.Otherwise,the products or devices designed will be of no further engineering or commercial interests.Nowadays,the simultaneous considerations ofmanufacturing and assembly factors phases including design,manufacturing,inspection,asassembly and other is considered in such a parallel fashion that the quality and cost arebest satisfied concurrently.In addition to these traditionally technological and economic considerations fundamental to the design and development of mechanical components and systems,the modern engineers have become increasingly concerned with the broader considerations of sustainability,ecology,aesthetics,ergonomics,maintainability,andoverall quality of life.It is clear that a greater than ever engineering effort is being recently devoted to broader considerations relating to the influences of engineered products on people as well as on the environment.The following is a list of general factors for engineers to consider in the design process,which from a different viewpoint shows us a panoramic picture with regard to the design-related activities and tasks.(1) Cost of manufacturing.Will the selling price be competitive? Are there cheaper ways of manufacturing the machine? Could other materials be used? Are any special tools,dies, jigs,or fixtures needed? Can it easily be inspected? Can the workshop produce it? Is heat treatment necessary? Can parts be easily welded?第4页Cost of operation.Are power requirements too large? What type of fuelwill be used? Will operation cost be less expensive?(3) Cost of maintenance.Are all parts easily accessible? Are access panels needed? Can common tools be used? Can replacement parts be available?(4) Safety features.Is a suitable factor of safety used? Does the safety factor meet existing codes? Are fuses,guards,and/or safety valves used? Are shear pins needed? Is there any radiation hazard? Any overlooked ”stress raiser”? Are there any dangerous fumes?(5) Packaging and transportation.Can the machine be readily packaged for shipping without breakage? Is its size suitable to parcel post regulations, freight car dimensions,or trailer truck size? Are shipping bolts necessary? Is its center of gravity in a desirable location?(6) Lubrication.Does the system need periodic checking? Is it automatic? Isit a sealed system?(7) Materials.Are chemical,physical,and mechanical properties suitable toits use? Is corrosion a factor? Will the materials withstand impact? Is thermal or electrical conductivity important? Will high or low temperatures present any problem? Will design stress keep parts reasonable in size?(8) Strength.Have dimensions of components been carefully calculated? Have all the load cases be taken into account? Have the stress concentrations been carefully considered? Has the fatigue effect be computed?(9) Kinematics.Does it provide necessary motion for moving parts? Are rotational speeds reasonable? Could linkages replace cams? What will be the bestchoice,the belts,chains or gears? Is intermittent motion needed?(10) Styling.Does the color have eye appeal? Is the sharp desirable? Is the machine well proportioned? Are the calibrations on dials easily read? Are the controls easy to operate?(11) Drawings.Are standardized parts used? Are the tolerances realistic? Is the surface finish over-specified? Must the design conform to any standards?(12) Ergonomics.Has the operator of the equipment been considered? Are the controls conveniently located to avoid operator fatigue? Are knobs,grab bars,hand wheels,levers,and dial calibrations of proper size to fit the average operator?1.4 A general procedure of machinery designWhatever design tasks the designers are expected to complete,theyalways,consciously or unconsciously,follow the similar process which goes as follows:(1)Studies of feasibilityAfter understanding the product functions,operational conditions,manufacturing constraints and key technologies,go on to uncover existing solutions to some similar problems so as to clarify the design tasks,understand the needs,present the major functional parameters and evaluate design tasks,proposal of design aims,and feasibility analysis.(2) Conceptual design of configurationAccording to the design of tasks and functional parameter,designs need to extensively search for various feasible configurations and alternatives.For convenience,usually,the system can be analyzed comprehensively by decomposing itinto power sources,transmission and work mechanisms.A great effort needs to be devoted to the analysis and synthesis of these different parts.For example,the power source may be selected from motor,engine and turbine.Each power source may have a range of power and kinematical parameters .Similarly, power trains may have numerous optionsavailable,e.g.belts,chains,gears,worm gears and many other drives.Obviously selecting an appropriate configuration would guarantee the Success of the whole design and the quality of the products.To make a best possible decision,an iterative process is normally required to select,analyze,compare and evaluate different configurations.At this stage,the goals involve sketching of configuration,determination of kinematical mechanisms,and evaluation of functional parameter(power and kinematics).(3)Detailed technical designBased on the design of configuration and parameters,a number ofassembly and component drawings will be completed to reflect the detaileddesign including kinematics,power,strength,stiffness,dynamics,stability,fatigue and SO on.Consideration should also be given to manufacturingfactors by presenting structural details,materials,and both geometricand dimensional tolerances.This part of work will also be carried out ina repeated process in drawings,calculation,evaluation and modificationuntil a best possible design is achieved.The goal at this stage is tocomplete assembly and component drawings,structural details,design calculations and detailed technical documentations.(4)Modification of designAfter the design is completed,a prototype is usually made for a more realistic physical assessment of the design quality.This will help correct any drawback or fault that may be overlooked or neglected during the design process.At this stage,the goal is to correct the design imperfection,test the potential manufacturing or assembly flaws and refine /improve design.1.5 Contents and tasks of the courseThe course Machinery Design will cover the following contents:(1)Preliminaries.the fundamental principles of machinery andComponents design,design theory,selection of materials,structure,friction,wear and lubrication.(2)Connection.sand.joints.thread.fasteners,keys,rivets,welds,bonds .and adhesive and interference joints.(3)Transmission.screws,chains,belts,gears,worms,bevel.gearsAnd helical gears.(4)Shaft.system.rolling—contact.bearings,slidingbearings,clutches,couplings,shafts,axles and spindles.(5)Other part s.springs,housings and frame s.The course centers on engineering design of mechanical components andis in a category of fundamental methodology and procedure.It is notfeasible or realistic for the students to become involved in the detaileddesign considerations associated with all machine components.Instead,the textbook has its main focus on some typical components and parts.However,the methodologies and procedures to be developed in this course can beextended to more design cases.For this reason,an emphasis will be laidon the methods and procedure s over the course so that the student s willgain a certain competence in applying these skills and knowledge todesigning more mechanical components.As a professional fundamental course,it will help students to acquirea sol id knowledge of mechanical design and engineering awareness.More specifically,the course will help to develop the students’ competence inthe following facets:Competence of creative design and solving practical problem;Competence of team work as well as professional presentation and communications:Competence of apprehending the design principles andregulations,synthesizing the knowledge to develop new designs:Competence of engineering research as well as using designcode s,handbooks,standards and references:Competence of doing experiments to solve problem in the design oftypical components:Competence of understanding newly introduced technological as well aseconomic codes to update the knowledge of machinery design.It is worth noticing that the course will also integrate a number ofpreceding relevant subjects at the university—level ,including mathematics ,physics,electronics,chemistry,solid mechanics,fluid mechanics,heat transfer,thermodynamics,computin9,and so forth.It will combine the knowledge about science and professional skills to solve somepractical engineering problems,which will significantly advance students’ competence and enlarge their vision to the professional engineers.It should be pointed out that skills and experience could beacquired only by a great deal of practice——hour after monotonous hour ofit.It is acknowledged universally that nothing worthwhile in life canbe achieved without hard work,often tedious,dull and monotonous,and engineering is no exception.机械设计的基本原则这个导言章节是对机械设计的一个纵览。

机械设计专业外文文献翻译

机械设计专业外文文献翻译

机械设计专业外文文献翻译general。

however。

materials that are easy to machine have high machinability。

while those that are difficult to machine have low XXX。

microstructure。

and mechanical properties。

as well as the XXX。

material。

and wear resistance.XXX factors。

cutting speed。

feed rate。

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

at high cutting speeds。

tool wear and cutting forces can increase。

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

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

but they can also increase cutting forces and heat n。

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

机械类外文文献及翻译

机械类外文文献及翻译

机械类外文文献及翻译(文档含中英文对照即英文原文和中文翻译)原文:GEAR AND SHAFT INTRODUCTIONAbstract:The important position of the wheel gear and shaft can't falter in traditional machine and modern machines.The wheel gear and shafts mainly install the direction that delivers the dint at the principal axis box. The passing to process to make them can is divided into many model numbers, using for many situations respectively. So we must be the multilayers to the understanding of the wheel gear and shaft in many ways .Key words: Wheel gear; ShaftIn the force analysis of spur gears, the forces are assumed to act in a single plane. We shall study gears in which the forces have three dimensions. The reason for this, in the case of helical gears, is that the teeth are not parallel to the axis of rotation. And in the case ofbevel gears, the rotational axes are not parallel to each other. There are also other reasons, as we shall learn.Helical gears are used to transmit motion between parallel shafts. The helix angle is the same on each gear, but one gear must have a right-hand helix and the other a left-hand helix. The shape of the tooth is an involute helicoid. If a piece of paper cut in the shape of a parallelogram is wrapped around a cylinder, the angular edge of the paper becomes a helix. If we unwind this paper, each point on the angular edge generates an involute curve. The surface obtained when every point on the edge generates an involute is called an involute helicoid.The initial contact of spur-gear teeth is a line extending all the way across the face of the tooth. The initial contact of helical gear teeth is a point, which changes into a line as the teeth come into more engagement. In spur gears the line of contact is parallel to the axis of the rotation; in helical gears, the line is diagonal across the face of the tooth. It is this gradual of the teeth and the smooth transfer of load from one tooth to another, which give helical gears the ability to transmit heavy loads at high speeds. Helical gears subject the shaft bearings to both radial and thrust loads. When the thrust loads become high or are objectionable for other reasons, it may be desirable to use double helical gears. A double helical gear (herringbone) is equivalent to two helical gears of opposite hand, mounted side by side on the same shaft. They develop opposite thrust reactions and thus cancel out the thrust load. When two or more single helical gears are mounted on the same shaft, the hand of the gears should be selected so as to produce the minimum thrust load.Crossed-helical, or spiral, gears are those in which the shaft centerlines are neither parallel nor intersecting. The teeth of crossed-helical fears have point contact with each other, which changes to line contact as the gears wear in. For this reason they will carry out very small loads and are mainly for instrumental applications, and are definitely not recommended for use in the transmission of power. There is on difference between a crossed heli : cal gear and a helical gear until they are mounted in mesh with each other. They are manufactured in the same way. A pair of meshed crossed helical gears usually have the same hand; that is ,a right-hand driver goes with a right-hand driven. In the design of crossed-helical gears, the minimum sliding velocity is obtained when the helix angle areequal. However, when the helix angle are not equal, the gear with the larger helix angle should be used as the driver if both gears have the same hand.Worm gears are similar to crossed helical gears. The pinion or worm has a small number of teeth, usually one to four, and since they completely wrap around the pitch cylinder they are called threads. Its mating gear is called a worm gear, which is not a true helical gear. A worm and worm gear are used to provide a high angular-velocity reduction between nonintersecting shafts which are usually at right angle. The worm gear is not a helical gear because its face is made concave to fit the curvature of the worm in order to provide line contact instead of point contact. However, a disadvantage of worm gearing is the high sliding velocities across the teeth, the same as with crossed helical gears.Worm gearing are either single or double enveloping. A single-enveloping gearing is onein which the gear wraps around or partially encloses the worm.. A gearing in which each element partially encloses the other is, of course, a double-enveloping worm gearing. The important difference between the two is that area contact exists between the teeth of double-enveloping gears while only line contact between those of single-enveloping gears. The worm and worm gear of a set have the same hand of helix as for crossed helical gears, but the helix angles are usually quite different. The helix angle on the worm is generally quite large, and that on the gear very small. Because of this, it is usual to specify the lead angle on the worm, which is the complement of the worm helix angle, and the helix angle on the gear; the two angles are equal for a 0-deg. Shaft angle.When gears are to be used to transmit motion between intersecting shaft, some of bevel gear is required. Although bevel gear are usually made for a shaft angle of 0 deg. They may be produced for almost any shaft angle. The teeth may be cast, milled, or generated. Only the generated teeth may be classed as accurate. In a typical bevel gear mounting, one of the gear is often mounted outboard of the bearing. This means that shaft deflection can be more pronounced and have a greater effect on the contact of teeth. Another difficulty, which occurs in predicting the stress in bevel-gear teeth, is the fact the teeth are tapered.Straight bevel gears are easy to design and simple to manufacture and give very good results in service if they are mounted accurately and positively. As in the case of squr gears, however, they become noisy at higher values of the pitch-line velocity. In these cases it is often go : od design practice to go to the spiral bevel gear, which is the bevel counterpart of thehelical gear. As in the case of helical gears, spiral bevel gears give a much smoother tooth action than straight bevel gears, and hence are useful where high speed are encountered.It is frequently desirable, as in the case of automotive differential applications, to have gearing similar to bevel gears but with the shaft offset. Such gears are called hypoid gears because their pitch surfaces are hyperboloids of revolution. The tooth action between such gears is a combination of rolling and sliding along a straight line and has much in common with that of worm gears.A shaft is a rotating or stationary member, usually of circular cross section, having mounted upon it such elementsas gears, pulleys, flywheels, cranks, sprockets, and other power-transmission elements. Shaft may be subjected to bending, tension, compression, or torsional loads, acting singly or in combination with one another. When they are combined, one may expect to find both static and fatigue strength to be important design considerations, since a single shaft may be subjected to static stresses, completely reversed, and repeated stresses, all acting at the same time.The word “shaft” covers numerous v ariations, such as axles and spindles. Anaxle is a shaft, wither stationary or rotating, nor subjected to torsion load. A shirt rotating shaft is often called a spindle.When either the lateral or the torsional deflection of a shaft must be held to close limits, the shaft must be sized on the basis of deflection before analyzing the stresses. The reason for this is that, if the shaft is made stiff enough so that the deflection is not too large, it is probable that the resulting stresses will be safe. But by no means should the designer assume that they are safe; it is almost always necessary to calculate them so that he knows they are within acceptable limits. Whenever possible, the power-transmission elements, such as gears or pullets, should be located close to the supporting bearings, This reduces the bending moment, and hence the deflection and bending stress.Although the von Mises-Hencky-Goodman method is difficult to use in design of shaft, it probably comes closest to predicting actual failure. Thus it is a good way of checking a shaft that has already been designed or of discovering why a particular shaft has failed in service. Furthermore, there are a considerable number of shaft-design problems in which the dimension are pretty well limited by other considerations, such as rigidity, and it is only necessary for the designer to discover something about the fillet sizes, heat-treatment,and surface finish and whether or not shot peening is necessary in order to achieve the required life and reliability.Because of the similarity of their functions, clutches and brakes are treated together. In a simplified dynamic representation of a friction clutch, or brake, two in : ertias I and I traveling at the respective angular velocities W and W, one of which may be zero in the case of brake, are to be brought to the same speed by engaging the clutch or brake. Slippage occurs because the two elements are running at different speeds and energy is dissipated during actuation, resulting in a temperature rise. In analyzing the performance of these devices we shall be interested in the actuating force, the torque transmitted, the energy loss and the temperature rise. The torque transmitted is related to the actuating force, the coefficient of friction, and the geometry of the clutch or brake. This is problem in static, which will have to be studied separately for eath geometric configuration. However, temperature rise is related to energy loss and can be studied without regard to the type of brake or clutch because the geometry of interest is the heat-dissipating surfaces. The various types of clutches and brakes may be classified as fllows:. Rim type with internally expanding shoes. Rim type with externally contracting shoes. Band type. Disk or axial type. Cone type. Miscellaneous typeThe analysis of all type of friction clutches and brakes use the same general procedure. The following step are necessary:. Assume or determine the distribution of pressure on the frictional surfaces.. Find a relation between the maximum pressure and the pressure at any point. Apply the condition of statical equilibrium to find (a) the actuating force, (b) the torque, and (c) the support reactions.Miscellaneous clutches include several types, such as the positive-contact clutches, overload-release clutches, overrunning clutches, magnetic fluid clutches, and others.A positive-contact clutch consists of a shift lever and two jaws. The greatest differences between the various types of positive clutches are concerned with the design of the jaws. To provide a longer period of time for shift action during engagement, the jaws may be ratchet-shaped, or gear-tooth-shaped. Sometimes a great many teeth or jaws are used, and they may be cut either circumferentially, so that they engage by cylindrical mating, or on the faces of the mating elements.Although positive clutches are not used to the extent of the frictional-contact type, they do have important applications where synchronous operation is required.Devices such as linear drives or motor-operated screw drivers must run to definite limit and then come to a stop. An overload-release type of clutch is required for these applications. These clutches are usually spring-loaded so as to release at a predetermined toque. The clicking sound which is heard when the overload point is reached is considered to be a desirable signal.An overrunning clutch or coupling permits the driven member of a machine to “freewheel” or “overrun” bec ause the driver is stopped or because another source of power increase the speed of the driven. This : type of clutch usually uses rollers or balls mounted between an outer sleeve and an inner member having flats machined around the periphery. Driving action is obtained by wedging the rollers between the sleeve and the flats. The clutch is therefore equivalent to a pawl and ratchet with an infinite number of teeth.Magnetic fluid clutch or brake is a relatively new development which has two parallel magnetic plates. Between these plates is a lubricated magnetic powder mixture. An electromagnetic coil is inserted somewhere in the magnetic circuit. By varying the excitation to this coil, the shearing strength of the magnetic fluid mixture may be accurately controlled. Thus any condition from a full slip to a frozen lockup may be obtained.齿轮和轴的介绍摘要:在传统机械和现代机械中齿轮和轴的重要地位是不可动摇的。

机械外文文献及翻译

机械外文文献及翻译

与机械相关的外文及翻译Multidisciplinary Design Optimization of Modular Industrial Robots by Utilizing High Level CAD Templates1、IntroductionIn the design of complex and tightly integrated engineering products, it is essential to be able to handle interactions between different subsystems of multidisciplinary nature [1]. To achieve an optimal design, a product must be treated as a complete system instead of developing subsystems independently [2]. MDO has been established as a convincing concurrent design optimization technique in development of such complex products [3,4].Furthermore, it has been pointed out that, regardless of discipline, basically all analyses require information that has to be extracted from a geometry model [5]. Hence, according to Bow-cutt [1], in order to enable integrated design analysis and optimization it is of vital importance to be able to integrate an automated parametric geometry generation system into the design framework. The automated geometry generation is a key enabler for so-called geometry-in-the-loop[6] multidisciplinary design frameworks, where the CAD geometries can serve as framework integrators for other engineering tools.To eliminate noncreative work, methods for creation and automatic generation of HLCt have been suggested by Tarkian [7].The principle of high HLCts is similar to high level primitives(HLP) suggested by La Rocca and van Tooren [8], with the exception that HLCts are created and utilized in a CAD environment.Otherwise, the basics of both HLP and HLCt can, as suggested byLa Rocca, be compared to parametric LEGOV Rblocks containing a set of design and analysis parameters. These are produced and stored in libraries, giving engineers or a computer agent the possibility to first topologically select the templates and then modify the morphology, meaning theshape,of each template parametrically.2、Multidisciplinary Design FrameworkMDO is a “systematic approach to design space exploration”[17], the implementation of which allows the designer to map the interdisciplinary relations that exist in a system. In this work, the MDO framework consists of a geometry model, a finite element(FE) model, a dynamic model and a basic cost model. The geometry model provides the analysis tools with geometric input. The dynamic model requires mass properties such as mass, center of gravity, and inertia. The FE model needs the meshed geometry of the robot as well as the force and torque interactions based on results of dynamic simulations.High fidelity models require an extensive evaluation time which has be taken into account. This shortcoming is addressed by applying surrogate models for the FE and the CAD models. The models are briefly presented below. 2.1 High Level CAD Template—Geometry ModelTraditionally, parametric CAD is mainly focused on morphological modifications of the geometry. However, there is a limit to morphological parameterization as follows:•The geometries cannot be radically modified.•Increased geometric complexity greatly increases parameterization complexity.The geometry model of the robot is generated with presaved HLCts, created in CATIA V5. These are topologically instantiated with unique internal design variables. Topological parameterization allows deletion, modification, and addition of geometricelements which leads to a much greater design space captured.Three types of HLCts are used to define the industrial robot topologically; Datum HLCt which includes wireframe references required for placement for the Actuator HLCTs and Structure HLCts, as seen Fig.2.Fig. 2 An industrial robot (left) and a modular industrial robot(right) The names of the references that must be provided for each HLCt instantiation are stored in the knowledge base (see Appen-dix A.4), which is searched through by the inference engine. In Appendix A, pseudocode examples describes how the references are retrieved and how they are stored in the knowledge base.The process starts by the user defining the number of degrees of freedom (DOF) of the robot (see Fig. 3) and is repeated until the number of axis (i) is equal to the user defined DOF.In order to instantiate the first Structure HLCt, two Datum and two actuator instances are needed. References from the two Datum instances help orienting the structure in space, while the geometries of the actuator instances, at both ends of the link, are used to construct the actuator attachments, as seen in Figs. 2 and 3. For the remaining links, only one new instance of both datum and actuator HLCts are required, since the datum and actuator instances from adjacent links are already available.Appendix A.2 shows a pseudocode example of an instantiation function. The first instantiated datum HLCt is defined with reference to the absolute coordinate system. The remaining datum HLCt instances are placed in a sequential order, where the coordinate system of previous instances is used as reference for defining the position in space according to user inputs (see also AppendixA.3). Furthermore, the type of each actuator and structure instance is user defined.Fig. 3 The high level CAD template instantiation process Since it is possible to create new HLCts in the utilized CAD tool, the users are not forced to merely choose from the templates available. New HLCts can be created, placed in the database and parametrically inserted into the models.2.2 Dynamic ModelThe objective of performing dynamic simulation of a robot is to evaluate system performance, such as predicting acceleration and time performance, but it also yields loads on each actuated axis, needed for actuator lifetime calculations and subsequent stress analysis based on FE calculations. Thedynamic model in the outlined framework is developed in Modelica using Dymola, and it constitutes a seven-axis robot arm based on the Modelica Standard library [18].The dynamic model receives input from the geometry model,as well as providing output to the FE model, which is further described in Sec. 2.3. However, to better understand the couplings between the models, the Newton –Euler formulation will be briefly discussed. In this formulation, the link velocities and acceleration are iteratively computed, forward recursivelyWhen the kinematic properties are computed, the force and torque interactions between the links are computed backward recursively from the last to the first link2.3 FE Surrogate ModelTo compute the structural strength of the robot, FE models for each robot link is created utilizing CATIA V5, see Fig. 4. For each HLCt, mesh and boundary conditions are manually preprocessed in order to allow for subsequent automation for FE-model creation. The time spent on preprocessing each FE-model is thus extensive. Nonetheless, the obtained parametric FE-model paves way for automated evaluation of a wide span of concepts. Each robot link is evaluated separately with the load conditions extracted from the dynamicmodel. The force (fi-11and fi) and torque (ţi-1and ti) are applied on the surfaceswhere the actuators are attached.2.4 Geometric Surrogate Models.Surrogate models are numerically efficient models to determine the relation between inputs and o utputs of a model [19]. The input variables for the proposed application are the morphological variables thickness and link height as well as a topological variable actuator type. The outputs of the surrogate models are mass m, Inertia I, and center of gravity ri,ci.To identify the most suitable type of surrogate model for the outlined problem, a range of surrogate models types are created and evaluated using 50 samples. The precision of each surrogate model is compared with the values of the original model with 20 new samples. The comparison is made using the relative average absolute error (RAAE) and relative maximum absolute error (RMAE) as specified by Shan et al. [20], as well as the normalized root mean square error (NRMSE), calculated as seen in Eq. (3). All precision metrics are desired to be as low as possible, since low values mean that the surrogate model is accurateThe resulting precision metrics can be seen in Appendix B and the general conclusion is that anisotropic kriging [21], neural networks [22], and radialbasis functions [23] are the most promising surrogate models. To investigate the impact of increasing number of samples, additional surrogate models of those three are fitted using 100 samples, and the results compiled in Appendix B. The resulting NRMSEs for 50 and 100 samples for anistotropic kriging, neural networks, and radial basis functions can be seen in Fig.5. The figures inside the parentheses indicate the number of samples used to fit the surrogate models.Fig. 5 Graph of the NRMSEs for different surrogate models,fitted using 50 and 100 samplesAccording to Fig. 5, anisotropic kriging outperforms the other surrogate models and the doubling of the number of samples usedfor fitting the surrogate model increases the precision dramatically.2.5 FE Surrogate ModelsFor generating FE surrogate models, the anisotropic kriging was also proven to be the most accurate compared to the methods evaluated in Sec. 2.4. Here, one surrogate model is created for each link. Inputs are thickness,actuators, force (fi-11and fi) and torque (ţi-1and ti). The output for eachsurrogate model is maximum stress (MS).A mean error of approximately 9% is reached when running 1400 samples for each link. The reason for the vast number of samples, compared to geometry surrogate models, has to do with a much larger design space.利用高水平CAD模板进行模块化工业机器人的多学科设计优化1 介绍指出,除了规则,基本上所有的分析都需要信息,而这些信息需要从一个几何模型中提取。

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

机械设计外文文献翻译、中英文翻译unavailable。

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

the designer can begin toXXX evaluated。

and the best one is XXX。

XXX.Mechanical DesignA XXX machines include engines。

turbines。

vehicles。

hoists。

printing presses。

washing machines。

and XXX and methods of design that apply to XXXXXX。

cams。

valves。

vessels。

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

Existing apparatus may require XXX。

efficiency。

weight。

speed。

or cost。

while new apparatus may be XXX。

To start。

the designer must define the problem and XXX。

ideas and concepts are generated。

evaluated。

and refined until the best one is XXX。

XXX.XXX。

assembly。

XXX.During the preliminary design stage。

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

they can be corrected early on in the design process。

机械类毕业设计外文翻译范文

机械类毕业设计外文翻译范文

机械类毕业设计外文翻译、毕业设计(论文)外译文题目:轴承的摩擦与润滑10 月 15 日外文文献原文:Friction , Lubrication of BearingIn many of the problem thus far , the student has been asked to disregard or neglect friction . Actually , friction is present to some degree whenever two parts are in contact and move on each other. The term friction refers to the resistance of two or more parts to movement.Friction is harmful or valuable depending upon where it occurs. friction is necessary for fastening devices such as screws and rivets which depend upon friction to hold the fastener andthe parts together. Belt drivers, brakes, and tires are additional applications where friction is necessary.The friction of moving parts in a machine is harmful because it reduces the mechanical advantage of the device. The heat produced by friction is lost energy because no work takes place. Also , greater power is required to overcome the increased friction. Heat is destructive in that it causes expansion. Expansion may cause a bearing or sliding surface to fit tighter. If a great enough pressure builds up because made from low temperature materials may melt.There are three types of friction which must be overcome in moving parts: (1)starting, (2)sliding, and(3)rolling. Starting friction is the friction between two solids that tend to resist movement. When two parts are at a state of rest, the surface irregularities of both parts tend to interlock and form a wedging action. T o produce motion in these parts, the wedge-shaped peaks and valleys of the stationary surfaces must be made to slide out and over each other. The rougher the two surfaces, the greater is starting friction resulting from their movement .Since there is usually no fixed pattern between the peaks and valleys of two mating parts, the irregularities do not interlock once the parts are in motion but slide over each other. The friction of the two surfaces is known as sliding friction. As shown in figure ,starting friction is always greater than sliding friction .Rolling friction occurs when roller devces are subjected to tremendous stress which cause the parts to change shape or deform. Under these conditions, the material in front of a roller tends to pile up and forces the object to roll slightly uphill. This changing of shape , known as deformation, causes a movement of molecules. As a result ,heat is produced from the addedenergy required to keep the parts turning and overcome friction.The friction caused by the wedging action of surface irregularities can be overcome partly by the precision machining of the surfaces. However, even these smooth surfaces may require the use of a substance between them to reduce the friction still more. This substance is usually a lubricant which provides a fine, thin oil film. The film keeps the surfaces apart and prevents the cohesive forces of the surfaces from coming in close contact and producing heat .Another way to reduce friction is to use different materials for the bearing surfaces and rotating parts. This explains why bronze bearings, soft alloys, and copper and tin iolite bearings are used with both soft and hardened steel shaft. The iolite bearing is porous. Thus, when the bearing is dipped in oil, capillary action carries the oil through the spaces of the bearing. This type of bearing carries its own lubricant to the points where the pressures are the greatest.Moving parts are lubricated to reduce friction, wear, and heat. The most commonly used lubricants are oils, greases, and graphite compounds. Each lubricant serves a different purpose. The conditions under which two moving surfaces are to work determine the type of lubricant to be used and the system selected for distributing the lubricant.On slow moving parts with a minimum of pressure, an oil groove is usually sufficient to distribute the required quantity of lubricant to the surfaces moving on each other .A second common method of lubrication is the splash system in which parts moving in a reservoir of lubricant pick up sufficient oil which is then distributed to all moving parts during each cycle. This system is used in the crankcase of lawn-mower engines to lubricate the crankshaft, connecting rod ,and parts of the piston.A lubrication system commonly used in industrial plants is the pressure system. In this system, a pump on a machine carries the lubricant to all of the bearing surfaces at a constant rate and quantity.There are numerous other systems of lubrication and a considerable number of lubricants available for any given set of operating conditions. Modern industry pays greater attention to the use of the proper lubricants than at previous time because of the increased speeds, pressures, and operating demands placed on equipment and devices.Although one of the main purposes of lubrication is reduce friction, any substance-liquid , solid , or gaseous-capable of controlling friction and wear between sliding surfaces can be classed as a lubricant.V arieties of lubricationUnlubricated sliding. Metals that have been carefully treated to remove all foreign materials seize and weld to one another when slid together. In the absence of such a high degree of cleanliness, adsorbed gases, water vapor ,oxides, and contaminants reduce frictio9n and the tendency to seize but usually result in severe wear; this is called “unlubricated ”or dry sliding.Fluid-film lubrication. Interposing a fluid film that completely separates the sliding surfaces results in fluid-film lubrication. The fluid may be introduced intentionally as the oil in the main bearing of an automobile, or unintentionally, as in the case of water between a smooth tuber tire and a wet pavement. Although the fluid is usually a liquid such as oil, water, and a wide。

机械类英语论文及翻译

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。

机械设计类英文文献及翻译

机械设计类英文文献及翻译

机械设计类英文文献及翻译Mechanical Design Literature:1. Title: "Mechanical design of an innovative wind turbine blade"Authors: A. Smith, B. JohnsonJournal: Renewable EnergySynopsis: This paper presents the mechanical design of a novel wind turbine blade. The design involves the utilization of advanced materials and structural analysis techniques to improve the efficiency and durability of the blade. The results show promising performance and potential for future applications in the wind energy industry.Translation: "一种创新风力发电机叶片的机械设计"期刊:可再生能源摘要:本文介绍了一种新型风力发电机叶片的机械设计。

该设计利用先进材料和结构分析技术,以提高叶片的效率和耐久性。

结果显示出良好的性能和未来在风能产业中的潜力。

2. Title: "Design and performance analysis of a robotic exoskeleton for rehabilitation"Authors: C. Wang, D. LiJournal: Robotics and Autonomous SystemsSynopsis: This study focuses on the mechanical design and performance analysis of a robotic exoskeleton for rehabilitation purposes. The exoskeleton is designed to assist patients with mobility impairments in their daily activities. The paper discusses the design considerations, kinematic analysis, and performance evaluation of the exoskeleton, providing insightsfor future improvements in rehabilitation robotics.Translation: "一种用于康复的机器人外骨骼的设计和性能分析"期刊:机器人与自主系统摘要:本研究针对一种用于康复目的的机器人外骨骼进行了机械设计和性能分析。

(完整版)机械类外文文献翻译

(完整版)机械类外文文献翻译

文献翻译英文原文:NOVEL METHOD OF REALIZING THE OPTIMAL TRANSMISSION OF THE CRANK-AND-ROCKER MECHANISM DESIGN Abstract: A novel method of realizing the optimal transmission of the crank-and-rocker mechanism is presented. The optimal combination design is made by finding the related optimal transmission parameters. The diagram of the optimal transmission is drawn. In the diagram, the relation among minimum transmission angle, the coefficient of travel speed variation, the oscillating angle of the rocker and the length of the bars is shown, concisely, conveniently and directly. The method possesses the main characteristic. That it is to achieve the optimal transmission parameters under the transmission angle by directly choosing in the diagram, according to the given requirements. The characteristics of the mechanical transmission can be improved to gain the optimal transmission effect by the method. Especially, the method is simple and convenient in practical use.Keywords:Crank-and-rocker mechanism, Optimal transmission angle, Coefficient of travel speed variationINTRODUCTIONBy conventional method of the crank-and-rocker design, it is very difficult to realize the optimal combination between the various parameters for optimal transmission. The figure-table design method introduced in this paper can help achieve this goal. With given conditions, we can, by only consulting the designing figures and tables, get the relations between every parameter and another of the designed crank-and-rocker mechanism. Thus the optimal transmission can be realized.The concerned designing theory and method, as well as the real cases of its application will be introduced later respectively.1ESTABLISHMENT OF DIAGRAM FOR OPTIMAL TRANSMISSION DESIGNIt is always one of the most important indexes that designers pursue to improve the efficiency and property of the transmission. The crank-and-rocker mechanism is widely used in the mechanical transmission. How to improve work ability and reduce unnecessary power losses is directly related to the coefficient of travel speed variation, the oscillating angle of the rocker and the ratio of the crank and rocker. The reasonable combination of these parameters takes an important effect on the efficiency and property of the mechanism, which mainly indicates in the evaluation of the minimum transmission angle.The aim realizing the optimal transmission of the mechanism is how to find themaximum of the minimum transmission angle. The design parameters are reasonably combined by the method of lessening constraints gradually and optimizing separately. Consequently, the complete constraint field realizing the optimal transmission is established.The following steps are taken in the usual design method. Firstly, the initial values of the length of rocker 3l and the oscillating angle of rocker ϕ are given. Then the value of the coefficient of travel speed variation K is chosen in the permitted range. Meanwhile, the coordinate of the fixed hinge of crank A possibly realized is calculated corresponding to value K .1.1 Length of bars of crank and rocker mechanismAs shown in Fig.1, left arc G C 2 is the permitted field of point A . Thecoordinates of point A are chosen by small step from point 2C to point G .The coordinates of point A are 02h y y c A -= (1)22A A y R x -= (2)where 0h , the step, is increased by small increment within range(0,H ). If the smaller the chosen step is, the higher the computational precision will be. R is the radius of the design circle. d is the distance from 2C to G .2cos )2cos(22cos 33ϕθϕϕ⎥⎦⎤⎢⎣⎡--+=l R l d (3) Calculating the length of arc 1AC and 2AC , the length of the bars of themechanism corresponding to point A is obtained [1,2].1.2 Minimum transmission angle min γMinimum transmission angle min γ(see Fig.2) is determined by the equations [3]322142322min 2)(cos l l l l l l --+=γ (4) 322142322max 2)(cos l l l l l l +-+=γ (5) max min180γγ-︒=' (6) where 1l ——Length of crank(mm)2l ——Length of connecting bar(mm)3l ——Length of rocker(mm)4l ——Length of machine frame(mm)Firstly, we choose minimum comparing min γ with minγ'. And then we record all values of min γ greater than or equal to ︒40 and choose the maximum of them.Secondly, we find the maximum of min γ corresponding to any oscillating angle ϕ which is chosen by small step in the permitted range (maximum of min γ is different oscillating angle ϕ and the coefficient of travel speed variation K ).Finally, we change the length of rockerl by small step similarly. Thus we3γcorresponding to the different length of bars, may obtain the maximum ofmindifferent oscillating angle ϕand the coefficient of travel speed variation K.Fig.3 is accomplished from Table for the purpose of diagram design.It is worth pointing out that whatever the length of rocker 3l is evaluated, the location that the maximum of min γ arises is only related to the ratio of the length of rocker and the length of machine frame 3l /4l , while independent of 3l .2 DESIGN METHOD2.1 Realizing the optimal transmission design given the coefficient of travelspeed variation and the maximum oscillating angle of the rockerThe design procedure is as follows.(1) According to given K and ϕ, taken account to the formula the extreme included angle θ is found. The corresponding ratio of the length of bars 3l /4l is obtained consulting Fig.3.︒⨯+-=18011K K θ (7) (2) Choose the length of rocker 3l according to the work requirement, the length of the machine frame is obtained from the ratio 3l /4l .(3) Choose the centre of fixed hinge D as the vertex arbitrarily, and plot an isosceles triangle, the side of which is equal to the length of rocker 3l (see Fig.4), andϕ=∠21DC C . Then plot 212C C M C ⊥, draw N C 1, and make angleθ-︒=∠9012N C C . Thus the point of intersection of M C 2 and N C 1 is gained. Finally, draw the circumcircle of triangle 21C PC ∆.(4) Plot an arc with point D as the centre of the circle, 4l as the radius. The arc intersections arc G C 2 at point A . Point A is just the centre of the fixed hinge of the crank.Therefore, from the length of the crank2/)(211AC AC l -= (8)and the length of the connecting bar112l AC l -= (9)we will obtain the crank and rocker mechanism consisted of 1l , 2l , 3l , and 4l .Thus the optimal transmission property is realized under given conditions.2.2 Realizing the optimal transmission design given the length of the rocker (or the length of the machine frame) and the coefficient of travel speed variationWe take the following steps.(1) The appropriate ratio of the bars 3l /4l can be chosen according to given K . Furthermore, we find the length of machine frame 4l (the length of rocker 3l ).(2) The corresponding oscillating angle of the rocker can be obtained consulting Fig.3. And we calculate the extreme included angle θ.Then repeat (3) and (4) in section 2.13 DESIGN EXAMPLEThe known conditions are that the coefficient of travel speed variation1818.1=K and maximum oscillating angle ︒=40ϕ. The crankandrockermechanism realizing the optimal transmission is designed by the diagram solution method presented above.First, with Eq.(7), we can calculate the extreme included angle ︒=15θ. Then, we find 93.0/43=l l consulting Fig.3 according to the values of θ and ϕ.If evaluate 503=l mm, then we will obtain 76.5393.0/504==l mm. Next, draw sketch(omitted).As result, the length of bars is 161=l mm,462=l mm,503=l mm,76.534=l mm.The minimum transmission angle is︒=--+=3698.462)(arccos 322142322min l l l l l l γ The results obtained by computer are 2227.161=l mm, 5093.442=l mm, 0000.503=l mm, 8986.534=l mm.Provided that the figure design is carried under the condition of the Auto CAD circumstances, very precise design results can be achieved.4 CONCLUSIONSA novel approach of diagram solution can realize the optimal transmission of the crank-and-rocker mechanism. The method is simple and convenient in the practical use. In conventional design of mechanism, taking 0.1 mm as the value of effective the precision of the component sizes will be enough.译文:认识曲柄摇臂机构设计的最优传动方法摘要:一种曲柄摇臂机构设计的最优传动的方法被提出。

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)

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。

机械设计制造论文外文翻译(中文有期刊号)英文原文已发

机械设计制造论文外文翻译(中文有期刊号)英文原文已发

潍坊学院学生毕业设计外文译文专业机械设计制造及其自动化班级08级机制本4学生姓名耿传锋学号08012130450学生成绩机电与车辆工程学院译文要求1.外文翻译必须使用钢笔,手工工整书写,或用A4纸打印。

2.所选的原文内容必须与课题或专业方向紧密相关,注明详细出处。

3.外文翻译书文本后附原文(或复印件),译文不少于3000字符。

译文评阅评阅要求:应根据学校“译文要求”,对学生译文的准确性、翻译数量以及译文的文字表述情况等作具体的评价。

指导教师评语:指导教师签名年月日分析模型导轨磨损的演算对机床加工精度的影响工程系副教授伊沃娜彼得,凯特林大学,工程系博士讲师卡门波帕,凯特林大学,工程系博士讲师杜米特鲁,凯特林大学,工程系西普里安,凯特林大学摘要:机床导轨磨损影响积极震动。

最初的刀具运动轨迹作为导轨磨损的结果,将被修改,尺寸精度产生差异的工件的几何形状和偏差。

因为它已经成为连接称为移动和刚性导轨的磨损取决于许多参数(压力,速度,长度摩擦,润滑,材料)。

一种或另一种分析模型和/或磨损的实验模型的选择取决于所的工作条件,假设被称为耦合材料。

目前的工作的目标是建立一个分析模型的演算显示导轨的影响磨损在工具机的加工精度。

关键词:精度机床表面。

1、简介因为它已经被称为加工精度取决于每一块技术系统(机床,夹紧装置,刀具等)[1,2,3]连接到多种因素。

在目前的工作,笔者的目标是建立规模和影响力的床身在对车床使用的机床的加工精度,导轨的磨损。

导轨的大小和(纵向)滑动磨损是重要的被称为因为滑动轨迹,由于磨损,时间条件下发生的尺寸偏差和加工零件的表面质量的变化。

以建立系统的床身滑动磨损大小,三种不同的情况正在分析:1 - 床身导轨正在磨损2 - 导轨只被磨损3 - 导轨(床身滑动)正在磨损2、建立床身滑动产生的误差分析模型磨损为了建立在加工的磨损过程的定量影响车床的精度,以下假设[2]:- 被认为是在一定的刚性指南U(X)的磨损轮廓曲线时刻评估应力循环的数量;- 比以前所有的周期产生的磨损,被忽视的电流应力周期的磨损;- 移动导轨磨损U1(L)是这样产生的,该导轨的性能如下;不断刚性指南轮廓;基于这个假设,它是承认接触的类型始终是按照正常和切向应力的适当分配;- 移动导轨位移在两个剖面的接触面,使正常的线是独一无二的刚性;- 磨损是一个连续的过程和特点是由连续拖到指导长度的功能和时间的考虑,磨损层的厚度。

机械设计制造及其自动化毕业论文中英文资料外文翻译

机械设计制造及其自动化毕业论文中英文资料外文翻译

机械设计创造及其自动化毕业论文外文文献翻译INTEGRATION OF MACHINERY译文题目专业机械设计创造及其自动化外文资料翻译INTEGRATION OF MACHINERY(From ELECTRICAL AND MACHINERY INDUSTRY)ABSTRACTMachinery was the modern science and technology development inevitable result, this article has summarized the integration of machinery technology basic outline and the development background .Summarized the domestic and foreign integration of machinery technology present situation, has analyzed the integration of machinery technology trend of development.Key word: integration of machinery ,technology, present situation ,product t,echnique of manufacture ,trend of development0. Introduction modern science and technology unceasing development, impelled different discipline intersecting enormously with the seepage, has caused the project domain technological revolution and the transformation .In mechanical engineering domain, because the microelectronic technology and the computer technology rapid development and forms to the mechanical industry seepage the integration of machinery, caused the mechanical industry the technical structure, the product organization, the function and the constitution, the production method and the management systemof by machinery for the characteristic integration ofdevelopment phase.1. Integration of machinery outline integration of machinery is refers in the organization new owner function, the power function, in the information processing function and the control function introduces the electronic technology, unifies the system the mechanism and the computerization design and the software which constitutes always to call. The integration of machinery development also has become one to have until now own system new discipline, not only develops along with the science and technology, but also entrusts with the new content .But its basic characteristic may summarize is: The integration of machinery is embarks from the system viewpoint, synthesis community technologies and so on utilization mechanical technology, microelectronic technology, automatic control technology, computer technology, information technology, sensing observation and control technology, electric power electronic technology, connection technology, information conversion technology as well as software programming technology, according to the system function goal and the optimized organization goal, reasonable disposition and the layout various functions unit, in multi-purpose, high grade, redundant reliable, in the low energy consumption significance realize the specific function value, and causes the overall system optimization the systems engineering technology .From this produces functional system, then becomes an integration of machinery systematic or the integration of machinery product. Therefore, of coveringtechnology is based on the above community technology organic fusion one kind of comprehensive technology, but is not mechanical technical, the microelectronic technology as well as other new technical simple combination, pieces together .This is the integration of machinery and the machinery adds the machinery electrification which the electricity forms in the concept basic difference .The mechanical engineering technology has the merely technical to develop the machinery electrification, still was the traditional machinery, its main function still was replaces with the enlargement physical strength .But after develops the integration of machinery, micro electron installment besides may substitute for certain mechanical parts the original function, but also can entrust with many new functions,like the automatic detection, the automatic reduction information, demonstrate the record, the automatic control and the control automatic diagnosis and the protection automatically and so on .Not only namely the integration of machinery product is human's hand and body extending, human's sense organ and the brains look, has the intellectualized characteristic is the integration of machinery and the machinery electrification distinguishes in the function essence.2. Integration of machinery development condition integration of machinery development may divide into 3 stages roughly.20th century 60's before for the first stage, this stage is called the initial stage .In this time, the people determination not on own initiative uses the electronic technology the preliminary achievement to consummate the mechanical product the performance .Specially in Second World War period, the war has stimulated the mechanical product and the electronic technology union, these mechanical and electrical union military technology, postwar transfers civilly, to postwar economical restoration positive function .Developed and the development at that time generally speaking also is at the spontaneouscondition .Because at that time the electronic technology development not yet achieved certain level, mechanical technical and electronic technology union also not impossible widespread and thorough development, already developed the product was also unable to promote massively. The 20th century 70~80 ages for the second stage, may be called the vigorous development stage .This time, the computer technology, the control technology, the communication development, has laid the technology base for the integration of machinery development . Large-scale, ultra large scale integrated circuit and microcomputer swift and violent development, has provided the full material base for the integration of machinery development .This time characteristic is :①A mechatronics word first generally is accepted in Japan, probably obtains the quite widespread acknowledgment to 1980s last stages in the worldwide scale ;②The integration of machinery technology and the product obtained the enormous development ;③The various countries start to the integration of machinery technology and the product give the very big attention and the support. 1990s later periods, started the integration of machinery technology the new stagewhich makes great strides forward to the intellectualized direction, the integration of machinery enters the thorough development time .At the same time, optics, the communication and so on entered the integration of machinery, processes the technology also zhan to appear tiny in the integration of machinery the foot, appeared the light integration of machinery and the micro integration of machinery and so on the new branch; On the other hand to the integration of machinery system modeling design, the analysis and the integrated method, the integration of machinery discipline system and the trend of development has all conducted the thorough research .At the same time, because the hugeprogress which domains and so on artificial intelligence technology, neural network technology and optical fiber technology obtain, opened the development vast world for the integration of machinery technology .These research, will urge the integration of machinery further to establish the integrity the foundation and forms the integrity gradually the scientific system. Our country is only then starts from the beginning of 1980s in this aspect to study with the application .The State Councilsummary had considered fully on international the influence which and possibly brought from this about the integration of machinery technology developmenttrend .Many universities, colleges and institutes, the development facility and some large and middle scale enterprises have done the massive work to this technical development and the application, does not yield certain result, but and so on the advanced countries compared with Japan still has the suitable disparity.3. Integration of machinery trend of development integrations of machinery are the collection machinery, the electron, optics, the control, the computer, the information and so on the multi-disciplinary overlapping syntheses, its development and the progress rely on and promote the correlation technology development and the progress .Therefore, the integration of machinery main development direction is as follows:3.1 Intellectualized intellectualizations are 21st century integration of machinery technological development important development directions .Theartificial intelligence obtains day by day in the integration of machinery constructor's research takes, the robot and the numerical control engine bedis to the machine behavior description, is in the control theory foundation, the absorption artificial intelligence, the operations research, the computer science, the fuzzy mathematics, the psychology, the physiology and the chaos dynamics and so on the new thought, the new method, simulate the human intelligence, enable it to have abilities and so on judgment inference, logical thinking, independent decision-making, obtains the higher control goal in order to .Indeed, enable the integration of machinery product to have with the human identical intelligence, is not impossible, also is nonessential .But, the high performance, the high speed microprocessor enable the integration of machinery product to have preliminary intelligent or human's partial intelligences, then is completely possible and essential.In the modern manufacture process, the information has become the control manufacture industry the determining factor, moreover is the most active actuation factor .Enhances the manufacture system information-handling capacity to become the modern manufacture science development a key point .As a result of the manufacture system information organization and structure multi-level, makes the information the gain, the integration and the fusion presents draws up the character, information measure multi-dimensional, as well as information organization's multi-level .In the manufacture information structural model, manufacture information uniform restraint, dissemination processing and magnanimous data aspects and so on manufacture knowledge library management, all also wait for further break through.Each kind of artificial intelligence tool and the computation intelligence method promoted the manufacture intelligence development in the manufacture widespread application .A kind based on the biological evolution algorithm computation intelligent agent, in includes thescheduling problem in the combination optimization solution area of technology, receives the more and more universal attention, hopefully completes the combination optimization question when the manufacture the solution speed and the solution precision aspect breaks through the question scale in pairs the restriction .The manufacture intelligence also displays in: The intelligent dispatch, the intelligent design, the intelligent processing, the robot study, the intelligent control, the intelligent craft plan, the intelligent diagnosis and so on are various These question key breakthrough, may form the product innovation the basic research system. Between 2 modern mechanical engineering front science different science overlapping fusion will have the new science accumulation, the economical development and society's progress has had the new request and the expectation to the science and technology, thus will form the front science .The front science also has solved and between the solution scientific question border area .The front science has the obvious time domain, the domain and the dynamic characteristic .The project front science distinguished in the general basic science important characteristic is it has covered the key science and technology question which the project actual appeared.Manufacture system is a complex large-scale system, for satisfies the manufacture system agility, the fast response and fast reorganization ability, must profit from the information science, the life sciences and the social sciences and so on the multi-disciplinary research results, the exploration manufacture system new architecture, the manufacture pattern and the manufacture system effective operational mechanism .Makes the system optimization the organizational structure and the good movement condition is makes the system modeling , the simulation and the optimized essential target .Not only the manufacture system new architecture to makes the enterprise the agility and may reorganize ability to the demand response ability to have the vital significance, moreover to made the enterprise first floor production equipment the flexibility and may dynamic reorganization ability set a higher request .The biological manufacture view more and more many is introduced the manufacture system, satisfies the manufacture system new request.The study organizes and circulates method and technique of complicated system from the biological phenomenon, is a valid exit which will solve many hard nut to cracks that manufacturing industry face from now on currently .Imitating to living what manufacturing point is mimicry living creature organ of from the organization, from match more, from growth with from evolution etc. function structure and circulate mode of a kind of manufacturing system and manufacturing process.The manufacturing drives in the mechanism under, continuously by one's own perfect raise on organizing structure and circulating mode and thus to adapt the process of[with] ability for the environment .For from descend but the last product proceed together a design and make a craft rules the auto of the distance born, produce system of dynamic state reorganization and product and manufacturing the system tend automatically excellent provided theories foundation and carry out acondition .Imitate to living a manufacturing to belong to manufacturing science and life science of"the far good luck is miscellaneous to hand over", it will produce to the manufacturing industry for 21 centuries huge of influence .机电一体化摘要机电一体化是现代科学技术发展的必然结果,本文简述了机电一体化技术的基本概要和发展背景。

机械设计外文翻译

机械设计外文翻译

西南交通大学本科毕业设计(论文)外文资料及翻译年级: 2007级学号: 20077657姓名: 王雪扬专业: 工程机械指导老师: 李春林2011年 5 月Loading machinesFor materials handing in construction,use is made of loaders.Practice has shown that excavators are less effective in the capacity of loads in quarries and storages of nonmetallic materials than loaders.By the kind of loads handled,loaders are classified as forklift loads and scooping loaders for loose materials.Sooping loaders are divided into single-bucket and continuous-action Multi-bucket loaders.Single-bucket loaders are general-purpose machines suited engineering and in applications requring continuous working process.Depending on the kind of running gear,crawler and anailable.Crawler loaders have a high passblibity and develop a great thrust efftort. Wheeled loaders feature a high manoeuvrability and high traveling speeds making no damage to the road pavement and the storage areas. Unloaders are used for unloading sand, gravel, crushed stone, cement form railway cars.Power and pneumatic unloaders are used,power for unloading materials from flat cars or gondola cars(open wagons)and pneumatic for unloading cement.The main working member of fork-lift loaders is the fork serving to load and unload piece loads. These loaders have different change attachments. When equipped with buckets or grabs, they are used for loading loose and small-piece materials, and the boom attachment makes these loaders suited for hoisting loads to a small heighe and sometimes for erection work in construction.Fork-lift loaders are operated on hard-pavement areas,therefore they are mainly used in storehouse and as factory materials-handing equipment.They are made on the basis of a truck therefore they are also called truck loaders.they are powered by internal combustion engines or electric motors with storage batteries.Engine powered truck are used for large warehouse and stock-handing application, for general yard work and fpr loading and unloading of vehicles. Torque converter transmission provides smooth operation; power steering and all-weather cabs are options available.Single-bucket loaders have a crawler tractor or a wheeled truck as a carrier mounting. The loader permits mechanization of loading construction and erection and work with the aid of change attachments,of which the main one is the bucket. The loading equipment is available in three modifications: front-end,overloading, and half-swing,jib-type. The front-end attachment provides also side unloading.The overloading modifiactaion permits back unloading. Presently front-end loader with the positive displacement hydraulic drives for the attachment are most widely used.The output of multi-bucket loaders is 40 to 60 percent higher than of single-bucket machines at the same power rating,it is expedient to use them in brickyards,prefabricated concrete products plants,railway stations with large volumes of loading-unloading operatins and also for loading loose materials.In addition,they are suited for size grading of loose materials,for which purpose they are provided with special vibrating screens.Multi-bucket loaders are very efficient in unloading flatcars with side dumping of the handle material.These loaders can be applied in the production lines of prefabricatde ainstruction products plants and also in road building.In the latter case they are used for loading sand and gravel into drying drums and mixers.The working member of the loader is a screw feeder consisting of tow right-hand and left-hand screws,which are arranged on both sides of a bucket elecator.When the feeder rotates,the loaded material is delivered to the buckets to make the scooping easier.A scraper is secured underneath the screw feeder.The elevator of the multi-bucket loader usually dischanges the material onto belt conveyers that deliver it to tiansport facilities.Some loaders discharge the handle material into tranport facilities through hoppers or chutes.装载机在建筑施工中,材料的装卸是用装载机和写在机进行的。

机械专业毕业设计外文翻译相关外文文献

机械专业毕业设计外文翻译相关外文文献

A new driver based on dual-mode frequency and phase control for traveling-wave type ultrasonic motorTien-Chi Chen a,*,Chih-Hsien Yu a ,Mi-Ching Tsai ba Department of Engineering Science,National Cheng Kung University,Tainan,Taiwan bDepartment of Mechanical Engineering,National Cheng Kung University,Tainan,Taiwana r t i c l e i n f o Article history:Received 6August 2007Accepted 24March 2008Available online 12May 2008Keywords:Ultrasonic motorFrequency and phase modulation controla b s t r a c tA mode conversion rotary traveling-wave ultrasonic motor (TWUSM)has potential applications in min-iature robotics.However,its electrical drive circuit presents unique challenges,particularly in producing a high frequency (about 40kHz),high voltage (400V peak-to-peak)signal input to a low impedance capacitive motor,while achieving high efficiency.A novel driving circuit is proposed to provide two-phase balance voltage for a TWUSM.This paper describes the design of TWUSM drive circuit,intended for simultaneously employs both the driving frequency and phase modulation control scheme.The oper-ating principles and a detailed analysis of the proposed driving circuit,consisting of voltage-controlled oscillator (VCO),voltage-controlled phase-shifter circuit and power amplifier circuit,are introduced.To drive the USM effectively a two-phase power amplifier converter using non-resonant technique was designed to provide a balanced two-phase voltage source,and the two-phase output driving voltages could be maintained at the same peak voltage value at the driving frequency under varying phase-mod-ulation processes.Detailed experimental results are provided to demonstrate the effectiveness of the pro-posed driving circuit.Crown Copyright Ó2008Published by Elsevier Ltd.All rights reserved.1.IntroductionThe ultrasonic motor (USM)has many excellent performance features,including high-retention torque,high torque at low speed,silence,compactness in size,and no electromagnetic inter-ference.The USM has been used in a number of industrial,medical,space,robotic,and automotive applications.The driving principles of the USM are high-frequency mechani-cal vibrations and frictional force and its mathematical model is thus difficult to derive.As a result,a lumped motor model of the USM is presently unavailable [1].Moreover,the control character-istics of the USM are complicated and highly nonlinear,as motor parameters are time-varying,owing to increases in temperature and changes in motor-drive operating conditions,such as driving frequency,source voltage and load.Basically,the speed of the TWUSM can be manipulated by con-trolling the frequency,phase difference and the voltage amplitude of the two sinusoidal voltage waveforms which input to the TWUSM.Many researchers have opted for the frequency of the sinusoidal voltage waveforms as the control variable [2–5].It can easily be controlled digitally and spans the entire allowable speed range of the TWUSM.Most TWUSMs contain a two-phase half-bridge series-resonant inverter with an approximated unityswitching frequency (f s )to resonant frequency (f o )ratio.According to the description in the previous paragraph,the quality factors of the two phases are different and time varying.Moreover,when the frequency ratio (f s /f o )of a series-resonant inverter approaches unity,the voltage gain varies severely with the variation of the quality factor [6].Thus,the two-phase sinusoid output voltages are unbalanced under the same switching frequency.Conse-quently,good dynamic performance of the USM is difficult to ob-tain due to the variation in the unbalanced peak values of the two-phase voltages.By contrast,a voltage amplitude control strat-egy using additional boost choppers was employed in [7].Each chopper–inverter driving circuit is composed of one boost chopper cascading with one half-bridge series-resonant parasitic load impedance inverter.Since the two phase constructions of the USM are coupled mechanically and the reaction from the electrical to the mechanical part is unbalanced for both phases,the equiva-lent two-phase loads of the rotor are unbalanced and varied for dif-ferent rotating directions,rotor speeds,load torque,applied voltages and static pressure force between stator and rotor.In addition,the internal two-phase blocking capacitors of the USM are unbalanced and will vary in value under different rotational directions.As a result,it is difficult maintain the two-phase sinu-soid output voltages at the same constant peak value at the same switching frequency.However,a driving circuit proposed by Lin and Kuo [8]operates within working limits where the inverter voltage gain is greatly affected by the variation of the quality0196-8904/$-see front matter Crown Copyright Ó2008Published by Elsevier Ltd.All rights reserved.doi:10.1016/j.enconman.2008.03.023*Corresponding author.E-mail address:tchichen@.tw (T.-C.Chen).Energy Conversion and Management 49(2008)2767–2775Contents lists available at ScienceDirectEnergy Conversion and Managementj ou r na l h om e pa ge :w w w.e lse vi e r.c om /lo c at e /en c on manfactor.Moreover,to resolve the difficulty of the amplitude varia-tion in the output voltages of the parallel-resonant inverter,an ex-tra energy feedback circuit is added to reduce the quality factors in the parallel-resonant circuit.However,the energy feedback circuit increases the complexity of the driving circuit.In addition to the use of a boost converter,a voltage amplitude control strategy may also be implemented using pulse-width mod-ulation(PWM).In[9],the voltage amplitude was adjusted by the forward and backward PWM method for position control of the TWUM.In[10],the voltage amplitude was adjusted by the ON–OFF PWM method for speed control.Both methods essentially adopted the same principle in which the modulation was used to control the ratio of the number of ultrasonic cycles within the for-ward-direction or on-time duration to the total number of ultra-sonic cycles,including the backward-direction or off-time duration.Such control methods cause intermittent operation of the TWUM,leading to the creation of severe audible noise.In order to suppress this audible noise,the PWM should be applied to each ultrasonic cycle[11].Given these limitations,a specific drive circuit control tech-nique is required.Hence,it is desirable to develop a novel drive system that solves these issues while supplying the necessary power with high efficiency.Compared to work on drive circuit design for TWUSM based on the phase difference between the two-phase voltages,less research has been done in other areas of drive circuit design for TWUSM. Only the phase difference control strategy offers the advantage of bidirectional rotation,while the other two parameters of the con-trol scheme,frequency and voltage amplitude,need the assistance of phase-shift change between p/2toÀp/2.In the design of modern drive circuits with adjustable phase dif-ferences,a low-cost and simple phase shifter circuit providing two-phase signals of two-phase voltage source is a critical design issue. The motivation of this study is to design a novel driving scheme that simultaneously employs both the driving frequency and phase difference as dual-mode control variables to handle system nonlin-earities and parameter variations.In order to reduce the system hardware size and cost,the proposed phase shifter circuit is imple-mented by using a voltage-controlled resistance(VCR)and all-pass filter circuit that can provide piecewise-linear phase control over the entire speed range.In the conventional series and parallel resonant converter archi-tecture,two inductances must be inserted in parallel or series with the load for each phase,respectively,in order to become resonant with the inherent two-phase parasitic capacitances of the USM. Moreover,the motor parameters of the USM are dependent on the operating temperature,the running time,and the load.In addi-tion,the equivalent two-phase loads of the rotor are also unbal-anced and the equivalent resistor values vary for different operating conditions.Therefore the quality factors of the resonant inverters in two-phase are unequal and time-varying,resulting in the consumption of time to determine suitable RLC tank compo-nents.In contrast with conventional series and parallel resonant converters with two reactive components,the power amplifier circuit in this study is implemented to build high-frequency two-phase high drive voltages for USM(e.g.400V peak to peak) and is not in need of additional reactive components or a compli-cated energy feedback circuit.Although the quality factors of the two RLC tanks vary at different rotating speeds and are not equal, the output driving voltage of the proposed power amplifier circuit in two-phase can be maintained at the same peak voltage value when the driving frequency is operated close to the resonant frequency.In this paper,the design of a novel phase shifter circuit for applying TWUSM driving is presented.For a USM prototype,the operating principles and characteristics at the operating conditions will be also briefly described.Next,the novel driving circuit for the TWUSM,which contains VCO,VCR,voltage-controlled phase shif-ter,and power amplifier driving circuit,is introduced.The results of experiments investigating the effectiveness of the proposed dri-ver are given in Section4.Finally,a discussion and conclusions are provided in Section5.2.Operating principle and characteristicIn the operation of the TWUSM,a two-stage energy conversion is formed.Thefirst stage consists of the electro-mechanical energy conversion where the electrical energy is converted into mechani-cal energy.This is achieved by excitation of the piezoelectric cera-mic by ultrasonic range frequency.The second stage comprises mechanical energy conversion where the mechanical vibrations are converted to linear or rotary motion by the friction force gen-erated in the stator–rotor interface.Fig.1illustrates the operating principles of the TWUSM.The stator,designed with comb-tooth surface,is attached above the sectors of piezoelectric elements. The piezoelectric elements are divided into sectors instead of form-ing a complete ring so that they can be applied with different voltages.The rotor is pressed against the stator by means of a pressure spring disc.It should be noted that the spring as shown is for illus-tration only,since in reality it is not a normal spring,but a pressure disc.The operating principle of the TWUSM is based on the mechanical vibrations of the piezoelectric elements.As a result of voltages applied to them,they produce a traveling wave in the sta-tor.The surface interaction between the stator and the rotor cre-ates a driving torque in the rotor.As shown in Fig.1, piezoelectric elements are positioned at an appropriate distance from one another.One is produces a mechanical vibration by being fed by the phase-A voltage source V m sin x t,while the other is fed by the phase-B voltage source V m sin(x t+U),generating another vibration,where V m is the amplitude,x=2p f is the angular version of frequency f,and U is the phase difference of the two driving volt-age sources.Each voltage source generates a mode of vibration throughout the stator,and the superposition of them forms a trav-eling wave that propagates along the stator.Depending on which phase of the voltage leads the other,the traveling wave will travel in either a right or left direction.Elliptical motion can be observed at the wave peak of the surface of the stator.Such motion produces a tangential force at the contact surface between the stator and the rotor.With a spring disc to keep the rotor in pressure contact with the stator,the rotor can be driven to travel in the opposite direc-tion from the traveling wave by this tangential force at the contactsurface.Fig.1.TWUSM operating principle[1].2768T.-C.Chen et al./Energy Conversion and Management49(2008)2767–2775The speed of the USM is controlled by:Frequency of two-phase voltages.Amplitude of two-phase voltages.Phase difference between two-phase voltages.3.Drive circuit designFig.2shows actual configuration view of a typical USR-60circu-lar traveling wave type motor(from Shinsei of Japan),in which the specification is a40kHz,0.32Nm,3W,120rev/min type motor. The operation of a mode conversion USM is based on the torque generated by piezoelectric ultrasonic vibrations.An optimal supply voltage for the USM is a sinusoidal voltage with frequency near the mechanical resonance frequency of the stator–rotor assembly. Since this USM presents a large capacitive load and requires a high operating frequency(40kHz),its equivalent impedance could be extremely low.This USM also requires a high drive voltage (400V peak-to-peak),which leads to a large drive current.The goals for drive circuit design are to satisfy these require-ments,as well as achieve high power efficiency and reduce the sys-tem hardware size and cost.In the design of modern drive circuit with adjustable phase difference,the key technology is a low-cost and simple phase shifter circuit,provided two-phase signals from a two-phase voltage source.The purpose of this study is to design a novel driving scheme that simultaneously employs both the driv-ing frequency and phase difference as the dual-mode control vari-ables to handle system nonlinearities and parameter variations. The block diagram of the driving circuit is shown in Fig.3.This cir-cuit is composed of voltage-controlled oscillator(VCO),voltage-controlled phase shifter,power amplifier,and transformer.The design procedures of the proposed drive system are described in detail below.3.1.Voltage-controlled oscillatorThe ICL8038waveform generator is a monolithic integrated cir-cuit capable of producing high accuracy sine,square,triangular, sawtooth,and pulse waveforms with a minimum of external com-ponents[12].The frequency(or repetition rate)can be selected externally from0.001Hz to more than300kHz using either resis-tors or capacitors,and frequency modulation and sweeping can be accomplished with an external frequency-modulated voltage(V f). The frequency of the waveform generator is a direct function of the DC voltage at Terminal8,shown in Fig.4.By altering this volt-age,frequency modulation is performed by means of a voltage-controlled oscillator(VCO).To clarify the relation between the frequency-modulated voltage and the magnitude of the single fre-quency,experimental measurements were made at different volt-age values in Fig.5.Fig.5shows that this characteristic is quite linear.In this study,motor speed is controlled at40–44kHz,which may be considered the linear frequency range.3.2.Voltage-controlled phase shifterFig.6shows afirst-order all-passfilter with a junctionfield-effect transistor(JFET)used as a variable resistor to control the pole and zero time constants in thefilter transfer function.Let VCR R eq be the resistance of the JFET.If we assume that this is a linear resis-tor,the transfer function isTðsÞ¼V oi¼s sÀ1ð1Þwhere the time constant s is given by s=R eq C.By varying the gate-source voltage of JFET(V GS),i.e.the phase-modulated voltage(V p)in Fig.3,the resistance of the JFET can be varied,which in turn changes the time constant s.For s=j x,the phase difference of the transfer function is therefore\Tðj xÞ¼À2tanÀ1x R eq Cð2ÞFig.2.The photograph of experimentalsetup.The magnitude of the transfer function (j T (j x )j )is 1for all fre-quency x .The phase displacement not only depends on the oper-ating frequency of the TWUSM but is also affected by the timeconstant (s ).At different frequencies,between 41and 44kHz,the voltage signal (V i )applied to the USM,the VCR (R eq )drifting through the control voltage (V GS ),and the relationship between them were measured (Table 1).At a specific resonant frequency (f o =41kHz),the goals for phase shifter circuit designed to adjust the phase differential from Àp /2to Àp rad.Fig.6shows a general all-pass filter circuit.The circuit is composed of a resistor,a capac-itor,and an operational amplifier.The frequency of the input signalfor the circuit has to be near the resonant frequency of the TWUSM.We inset the VCR instead of the resistor,and adjusted the proper-ties of the circuit components (R =10k X ,C =0.01l F).As a result,when the operating frequency equal the resonant frequency (f o )and the control voltage minimizes as zero (V GS =0),the phase dis-placement reaches Àp /2rad,i.e.x R eq C =1.Conversely,if the R eq is increased in small increments,the phase difference gradually diminishes.3.3.Voltage-controlled resistanceVoltage-controlled filter,voltage-controlled oscillators,and voltage-to-time period/frequency converters have been applied in many instrumentation and measurement situations.A simple way to realize such circuits is to start from known circuits and then replace resistors by voltage-controlled resistances (VCR).Schemes to construct such VCR using FET’s are known in literature [13].Fig.4.A voltage-controlled oscillatorcircuit.Fig. 5.The measured relation between controlled voltage and output single frequency.Table 1Measurement results of V GS versus R eq V GS (V)0À0.2À0.4À0.6À0.8À1.0R eq (X )357.1416.7471.7531.9617.3746.3V GS (V)À1.2À1.4À1.6À1.8À2.0À2.2R eq (X )943.4128219233846291661Fig.8.FET output characteristics (K30A).2770T.-C.Chen et al./Energy Conversion and Management 49(2008)2767–2775The VCR configuration is shown in Fig.7.A routine analysis of the circuit shows that when the FET is confined to operate in a non-saturated region under the same constraints as in [13,14],the output characteristic of the FET may be represented by a qua-dratic function given by I DS ¼I DSS V p½2ðV GS ÀV p ÞV DS ÀV 2DSð3Þwhere I DSS and V p are saturation current and pinch-off voltage,respectively.The implementation of the voltage-tunable resistance can be simplified by neglecting the V 2DS term of Eq.(3),in which case R eq would be R eq¼V DS DS %V 2pDSS GS p ;providedV DS <j 0:5jð4ÞA typical set of characteristics obtained experimentally for an n-channel JFET (K30A)is shown in Fig.8.The range of values includes those prescribed in [14]as well as larger values,to show the nonlinear nature of these curves.Clearly if thisfield-effectFig.9.Phase displacement against controlvoltage.Fig.10.Measured results of the divergent index coefficient under difference ope-rating control voltage.Fig.12.Generated signals of phase-shifted circuit.(a)Phase difference set at p /2rad (b)p /3(c)p /6(d)0(e)Àp /6(f)Àp /3(g)Àp /2.Fig.13.Measured results of the phase shifter circuit under difference operating driving frequency.T.-C.Chen et al./Energy Conversion and Management 49(2008)2767–27752771transistor(FET)is to be used as a bidirectional linear resistor,j V DS j should be kept low,at least less than500mV,particularly for prac-tical circuit applications.For the relationship between the phase displacement angle(U) and the control voltage(V GS),the analysis of the phase shifter cir-cuit should yield the following results by observing the phase dis-placement versus control voltage curve in Fig.9x R eq C%tanðaV GSþbÞð5ÞUsing Eq.(5)to simplify Eq.(2),the following relationship results:\T¼À2ðaVGSþbÞð6Þwhere the constants a and b are calculated to define as a=À0.3865, b=p/4,and were used in the verifications below.Note that,as ex-pected,even nonlinearities do not appear in Eq.(6),as they are can-celed out.In the following,we test the divergence between the theoretical formula and experimental data and also define the divergent index coefficient D(the ratio of the phase value according to Eq.(6)di-vided by the actual phase displacement relating to Eq.(2)of exper-imental data)asD¼À2ðaV GSþbÞÀ2tanÀ1ðx R eq CÞð7ÞTo illustrate the difference between(2)and(6),actual and esti-mated UÀV GS curves using both schemes are presented in Fig.9. The measured index coefficient(D)of the divergence as the input control voltage swing during different operating values is shown in Fig.10.As thisfigure shows,a reasonably good correspondence is observed between the two sets of data,confirming the validity of the above supposition property regarding Eq.(6).A phase shifter circuit was designed to provide two-phase sig-nals of two-phase driving voltage sources with a phase difference ranging from p/2toÀp/2.To design a low-cost,simple phase shifter circuit for a TWUSM,we constructed a phase-regulating driving circuit for the USM by utilizing the VCR and all-passfilter circuit.The proposed phase shifter circuit,shown in Fig.11, has dual complementary channels,in which the sinusoid output signals have angles complementary to each other (\A+\B=90°).The driving voltage signals with the phase difference from the phase shifter circuit for the resonance frequency of TWUSMsetFig.14.A Push–pull class-B amplifier with Darlingtonpairs.Fig.15.Rotational speed versus driving frequency under freeloading.Fig.16.Two-phase output voltages of phase-modulation driving circuit for drivingfrequency set at41kHz:the phase regulated as equal value.2772T.-C.Chen et al./Energy Conversion and Management49(2008)2767–2775at 40kHz are shown in Fig.12.Even if the phase in the phase shifter circuit was slightly affected by the operating driving frequency,the output signals in phase A and B can still maintain symmetrical amplitude and the range of phase difference reaches ±p /2rad.By observing the characteristics of the measured phase difference angle versus the phase-modulated voltage (V p ),shown in Fig.13,we found that the relationship between the phase difference angle (U )and phase-modulated voltage (V p )is highly linear over a wide operating range under different driving frequencies.3.4.Power amplifiers and transformerA practical circuit using ClassB elements is a complementary pair or push–pull arrangement.Here,complementary devices are used to each amplify the opposite halves of the input signal,which is then recombined at the output.This arrangement gives excellent efficiency,but can suffer from the drawback of a small glitch at the joins between the two halves of the signal,a problem known as crossover distortion.A solution to this is to bias the devices just on,rather than off altogether,when they are not in use.One way to greatly boost the current gain (A I )of a Class B push–pull ampli-fier is to use Darlington pairs instead of single transistors,shown in Fig.14.Since this USM presents a large capacitive load and requires a high operating frequency,its equivalent impedance could be extre-mely low.This USM also requires a high drive voltage,which leads to a large drive current.Hence,a ferrite-core transformer which features high efficiency,small size,and light weight,was chosen to isolate and boost the high frequency AC voltage.The non-reso-nant power amplifier circuits are designed in order to provide two-phase,phase A and B,sinusoid output voltages V A and V B with the same amplitude under the variable frequency and phase con-trol.According to experiment test in Section 4,the amplitude of the output voltage will not be affected by the variation of the qual-ity when the driving frequency is operated closely to the resonant frequency of the TWUSM.The phase B power amplifier circuit is designed using the same method as for phase A.4.Experimental resultsA prototype of power driver for a TWUSM was built and tested.Based on the circuit design of TWUSM driver discussed above,mo-tor performance was measured by experimental results.There are three basic input signals for the TWUSM:frequency,independence amplitude,and phase.It is important to confirm the driving char-acteristics for eachparameter.Fig.17.Experimental results of phase-modulation driving circuit for driving frequency set at 41kHz,10l s/div.(a)Two-phase output voltages with phase difference p /6for CW rotation.(b)Two-phase output voltages with phase difference p /6for CCWrotation.Fig.18.Experimental results of phase-modulation driving circuit for driving frequency set at 41kHz,10l s/div.(a)Two-phase output voltages with phase difference p /3for CW rotation.(b)Two-phase output voltages with phase difference p /3for CCW rotation.T.-C.Chen et al./Energy Conversion and Management 49(2008)2767–27752773First,we measured the rotational speed in relation to the driv-ing frequency in Fig.15.The mechanical resonant frequency of the USM (USR-60)ranges from 39to 40kHz in the ultrasonic fre-quency range.The switching frequency of the voltage-controlled oscillator,which is designed to vary between 40.5and 44kHz,should be higher than the resonant frequency of the mechanical vibration.The highest rotational speeds around the phase differ-ence p /2were roughly 229and 221rpm in the direction of CW and CCW,respectively.The frequency,at around 40.5kHz,is nearly the same as the natural resonance frequency of TWUSM as de-scribed above.This characteristic is the same as that of a conven-tional single-frequency-mode control ultrasonic motor.The vibration velocity becomes high near the resonant frequency of the stator,which means the rotational velocity of the rotor reaches its maximum value.Subsequently,we tested the rotational speed in relation to the phase difference.The phase shifter circuit worked as mentioned above.The control input to the drive circuit (V p )is calculated by the control algorithm.According to the control input,the phase dif-ference (U )is regulated by means of the designed phase shifter cir-cuit.The phase shifter circuit is designed for the two-phase power amplifier to provide two-phase output voltages V A and V B with var-iable phase difference,where the rotational direction (CW or CCW)can be controlled by allowing either V A or V B to lead.In order to as-sess the performance and stability of the proposed phase-mode driver for TWUSM,the phase differences of two-phase AC outputvoltage has been regulated from 0to ±p /2rad,shown in Figs.16–19,respectively.The two-phase sinusoid output V A and V B can thus be maintained at the same constant peak value at the switching frequency under varying phase-modulation processes.The driving phase difference of the designed phase-shifter circuit is the major control variable,and balanced two-phase sinusoid output voltages with the same amplitudes and variable-phase control results in satisfactory control performance of the TWUSM servo drive.Fig.20shows the experimental results of the Speed versus phase difference curves under variable operating driving frequencies.Experimental results confirm that the rotor could be rotated using the design driving circuit.By comparison,the phase-mode driving can offer a much wider controllable range,which verifies that the proposed driver circuit can successfully adapt the change of com-mand signals.In addition to these advantages,only the phase shift parameter can control the rotational direction of a rotor,which the phase-shift varies between p /2and Àp /2.5.ConclusionsUSMs are potentially interesting for a number of industry appli-cations,such as miniature robotics.Their electrical drive circuits present unique challenges,particularly in producing signals of several hundred volts and tens of kilohertz with variable phase dif-ferences,inputted to a low impedance capacitive motor,whileFig.20.Rotational speed versus phase difference under difference operating drivingfrequency.Fig.19.Experimental results of phase-modulation driving circuit for driving frequency set at 41kHz,10l s/div.(a)Two-phase output voltages with phase difference p /2for CW rotation.(b)Two-phase output voltages with phase difference p /2for CCW rotation.2774T.-C.Chen et al./Energy Conversion and Management 49(2008)2767–2775。

机械设计英文文献(带翻译)

机械设计英文文献(带翻译)

英语文献翻译Introduction of MachiningHave a shape as a processing method, all machining process for the production of the most commonly used and most important method. Machining process is a process generated shape, in this process, Drivers device on the work piece material to be in the form of chip removal. Although in some occasions, the workpiece under no circumstances, the use of mobile equipment to the processing, However, the majority of the machining is not only supporting the workpiece also supporting tools and equipment to complete.Machining know the process has two aspects. Small group of low-cost production. For casting, forging and machining pressure, every production of a specific shape of the workpiece, even a spare parts, almost have to spend the high cost of processing. Welding to rely on the shape of the structure, to a large extent, depend on effective in the form of raw materials. In general, through the use of expensive equipment and without special processing conditions, can be almost any type of raw materials, mechanical processing to convert the raw materials processed into the arbitrary shape of the structure, as long as the external dimensions large enough, it is possible. Because of a production of spare parts, even when the parts and structure of the production batch sizes aresuitable for the original casting, Forging or pressure processing to produce, but usually prefer machining.Strict precision and good surface finish, machining the second purpose is the establishment of the high precision and surface finish possible on the basis of. Many parts, if any other means of production belonging to the large-scale production, Well Machining is a low-tolerance and can meet the requirements of small batch production. Besides, many parts on the production and processing of coarse process to improve its general shape of the surface. It is only necessary precision and choose only the surface machining. For instance, thread, in addition to mechanical processing, almost no other processing method for processing. Another example is the blacksmith pieces keyhole processing, as well as training to be conducted immediately after the mechanical completion of the processing.Primary Cutting ParametersCutting the work piece and tool based on the basic relationship between the following four elements to fully describe : the tool geometry, cutting speed, feed rate, depth and penetration of a cutting tool.Cutting Tools must be of a suitable material to manufacture, it must be strong, tough, hard and wear-resistant. Tool geometry -- to the tip plane and cutter angle characteristics -- for each cutting process must be correct.Cutting speed is the cutting edge of work piece surface rate, it is inches per minute to show. In order to effectively processing, and cutting speed must adapt to the level of specific parts -- with knives. Generally, the more hard work piece material, the lower the rate.Progressive Tool to speed is cut into the work piece speed. If the work piece or tool for rotating movement, feed rate per round over the number of inches to the measurement. When the work piece or tool for reciprocating movement and feed rate on each trip through the measurement of inches. Generally, in other conditions, feed rate and cutting speed is inversely proportional to.Depth of penetration of a cutting tool -- to inches dollars -- is the tool to the work piece distance. Rotary cutting it to the chip or equal to the width of the linear cutting chip thickness. Rough than finishing, deeper penetration of a cutting tool depth.Rough machining and finishing machiningThere are two kinds of cuts in machine- shop work called, respectively, the "roughing cut" and the "finishing cut". When a piece is "roughed out", it is quite near the shape and size required, but enough metal has been left on the surface to finish smooth and to exact size." Generally speaking, bars of steel, forging, castings, etc. are machined to the required shape and size with only one roughing and one finishing cut. Sometimes, however, certain portions of a piece may require more thanone roughing cut. Also, in some jobs, for example, when great accuracy is not needed, or when a comparatively small amount of metal must be removed, a finishing cut may be all that is required. The roughing cut, to remove the greater part of the excess material, should be reasonably heavy, that is, all the machine, or cutting tool, or work, or all three, will stand. So the machinist’s purpose is to remove the excess stock as fast as he can without leaving, at the same time, a surface too torn and rough, without bending the piece if it is slender, and without spoiling the centers. The finishing cut, to make the work smooth and accurate, is a finer cut. The emphasis here is refinement - very sharp tool, comparatively little metal removed, and a higher degree of accuracy in measurement. Whether roughing or finishing, the machinist must set the machine for the given job. He must consider the size and shape of the work and the kind of material, also the kind of tool used and the nature of the cut to be made, then he proceeds to set the machine for the correct speed and feed and to set the tool to take the depth of cut desired.Automatic Fixture DesignAssembly equipment used in the traditional synchronous fixture put parts of the fixture mobile center, to ensure that components from transmission from the plane or equipment plate placed after removal has been scheduled for position. However, in certain applications, mobile mandatory parts of the center line, it may cause parts or equipmentdamage. When parts vulnerability and may lead to a small vibration abandoned, or when their location is by machine spindle or specific to die, Tolerance again or when the request is a sophisticated, it would rather let the fixture to adapt to the location of parts, and not the contrary. For these tasks, Elyria, Ohio, the company has developed Zaytran a general non-functional data synchronization West category FLEXIBILITY fixture. Fixture because of the interaction and synchronization devices is independent; the synchronous device can use sophisticated equipment to replace the slip without affecting the fixture force. Fixture specification range from 0.2 inches itinerary, 5 pounds clamping force of the six-inch trip, 400-inch clamping force. The characteristics of modern production are becoming smaller and smaller quantities and product specifications biggest changes. Therefore, in the final stages of production, assembly of production, quantity and product design changes appear to be particularly vulnerable. This situation is forcing many companies to make greater efforts to rationalize the extensive reform and the previously mentioned case of assembly automation. Despite flexible fixture behind the rapid development of flexible transport and handling devices, such as backward in the development of industrial robots, it is still expected to increase the flexibility fixture. In fact the important fixture devices -- the production of the devices to strengthen investment on the fixture so that more flexibility in economic support holders.According to their flexibility and fixture can be divided into: special fixture, the fixture combinations, the standard fixture, high flexible fixture. Flexible fixture on different parts of their high adaptability and the few low-cost replacement for the characteristic.Forms can transform the structure of the flexible fixture can be installed with the change of structure components (such as needle cheek plate, Multi-chip components and flake cheek plate), a non-standard work piece gripper or clamping elements (for example: commencement standard with a clamping fixture and mobile components fixture supporting documents), or with ceramic or hardening of the intermediary substances (such as : Mobile particle bed fixture and heat fixture tight fixture). To production, the parts were secured fixture, the need to generate clamping function, its fixture with a few unrelated to the sexual submissive steps.According to the processing was part of that foundation and working characteristics to determine the work piece fixture in the required position, then need to select some stability flat combination, These constitute a stable plane was fixed in the work piece fixture set position on the clamp-profile structure, all balanced and torque, it has also ensured that the work features close to the work piece. Finally, it must be calculated and adjusted, assembly or disassembly be standard fixture components required for the position, so that the work piece firmly by clampingfixture in China. In accordance with this procedure, the outline fixture structure and equipped with the planning and recording process can be automated control.Structural modeling task is to produce some stable flat combination, Thus, these plane of the work pieces clamping force and will fixture stability. According to usual practice, this task can be human-machine dialogue that is almost completely automated way to completion. A man-machine dialogue that is automated fixture structure modeling to determine the merits can be conducted in an organized and planning fixture design reduce the amount of the design, shortening the study period and better distribution of work conditions. In short, can be successfully achieved significantly improve fixture efficiency and effectiveness.Fully prepared to structure programs and the number of material circumstances, the completion of the first successful assembly can save up to 60% of the time.Therefore fixture process modeling agencies is the purpose of the program has appropriate documents.机械加工机械加工是所有制造过程中最普遍使用的而且是最重要的方法。

机械专业外文翻译

机械专业外文翻译

编号:毕业设计(论文)外文翻译(原文)学院: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:机电工程学院指导老师:***职称:副教授2016年 6 月 1 日资料来源:文章名:INTEGRATION OF MACHINERY书刊名:《Digital Image Processing》作者:Y. Torres, J. J. Pavón, I. Nieto and J. A. Rodríguez出版社:武汉大学出版社,2004章节:2.4 INTEGRATION OF MACHINERY页码:P15~P18INTEGRATION OF MACHINERY(From ELECTRICAL AND MACHINERY INDUSTRY)ABSTRACTMachinery was the modern science and technology development inevitable result, this article has summarized the integration of machinery technology basic outline and the development background .Summarized the domestic and foreign integration of machinery technology present situation, has analyzed the integration of machinery technology trend of development.Key word:integration of machinery ,technology,present situation ,product t,echnique of manufacture ,trend of development0. Introduction modern science and technology unceasing development, impelled different discipline intersecting enormously with the seepage, has caused the project domain technological revolution and the transformation .In mechanical engineering domain, because the microelectronic technology and the computer technology rapid development and forms to the mechanical industry seepage the integration of machinery, caused the mechanical industry the technical structure, the product organization, the function and the constitution, the production method and the management system has had the huge change, caused the industrial production to enter into "the integration of machinery" by "the machinery electrification" for the characteristic development phase.1. Integration of machinery outline integration of machinery is refers in the organization new owner function, the power function, in the information processing function and the control function introduces the electronic technology, unifies the system the mechanism and the computerization design and the software which constitutes always to call. The integration of machinery development also has become one to have until now own system new discipline, not only develops along with the science and technology, but also entrusts with the new content .But its basic characteristic may summarize is: The integration of machinery is embarks from the system viewpoint, synthesis community technologies and so on utilization mechanical technology, microelectronic technology, automatic control technology, computer technology, information technology, sensing observation and control technology, electric power electronic technology, connection technology, information conversion technology as well as software programming technology, according to the system function goal and the optimized organization goal, reasonable disposition and the layout various functions unit, in multi-purpose, high grade, redundant reliable, in the low energy consumption significance realize the specific function value, and causes the overall system optimization the systems engineering technology .From this produces functional system, then becomes an integration of machinery systematic or the integration of machinery product. Therefore, "integration of machinery" covering "technology" and "product" two aspects .Only is, the integration of machinery technology is based on the above community technology organic fusion one kind of comprehensive technology, but is not mechanical technical, the microelectronic technology as well as other new technical simple combination, pieces together .This is the integration of machinery and the machinery adds the machinery electrification which the electricity forms in the concept basic difference .The mechanical engineering technology has the merely technical to develop the machinery electrification, still was the traditional machinery, its main function still was replaces with the enlargement physical strength .But after develops the integration of machinery, micro electron installment besides may substitute for certain mechanical parts the original function, but also can entrust with many new functions, like the automatic detection, the automatic reduction information, demonstrate the record, the automatic control and the control automatic diagnosis and the protection automatically and so on .Not only namely the integration of machinery product is human's hand and body extending, human's sense organ and the brains look, has theintellectualized characteristic is the integration of machinery and the machinery electrification distinguishes in the function essence.2. Integration of machinery development condition integration of machinery development may divide into 3 stages roughly.20th century 60's before for the first stage, this stage is called the initial stage .In this time, the people determination not on own initiative uses the electronic technology the preliminary achievement to consummate the mechanical product the performance .Specially in Second World War period, the war has stimulated the mechanical product and the electronic technology union, these mechanical and electrical union military technology, postwar transfers civilly, to postwar economical restoration positive function .Developed and the development at that time generally speaking also is at the spontaneous condition .Because at that time the electronic technology development not yet achieved certain level, mechanical technical and electronic technology union also not impossible widespread and thorough development, already developed the product was also unable to promote massively. The 20th century 70~80 ages for the second stage, may be called the vigorous development stage .This time, the computer technology, the control technology, the communication development, has laid the technology base for the integration of machinery development . Large-scale, ultra large scale integrated circuit and microcomputer swift and violent development, has provided the full material base for the integration of machinery development .This time characteristic is :①A mechatronics word first generally is accepted in Japan, probably obtains the quite widespread acknowledgment to 1980s last stages in the worldwide scale ;②The integration of machinery technology and the product obtained the enormous development ;③The various countries start to the integration of machinery technology and the product give the very big attention and the support. 1990s later periods, started the integration of machinery technology the new stage which makes great strides forward to the intellectualized direction, the integration of machinery enters the thorough development time .At the same time, optics, the communication and so on entered the integration of machinery, processes the technology also zhan to appear tiny in the integration of machinery the foot, appeared the light integration of machinery and the micro integration of machinery and so on the new branch; On the other hand to the integration of machinery system modeling design, the analysis and the integrated method, the integration of machinery discipline system and thetrend of development has all conducted the thorough research .At the same time, because the hugeprogress which domains and so on artificial intelligence technology, neural network technology and optical fiber technology obtain, opened the development vast world for the integration of machinery technology .These research, will urge the integration of machinery further to establish the integrity the foundation and forms the integrity gradually the scientific system. Our country is only then starts from the beginning of 1980s in this aspect to study with the application .The State Council had been established the integration of machinery leading group and lists as "863 plans" this technology .When formulated "95" the plan and in 2010 developed the summary had considered fully on international the influence which and possibly brought from this about the integration of machinery technology development trend .Many universities, colleges and institutes, the development facility and some large and middle scale enterprises have done the massive work to this technical development and the application, does not yield certain result, but and so on the advanced countries compared with Japan still has the suitable disparity.3. Integration of machinery trend of development integrations of machinery are the collection machinery, the electron, optics, the control, the computer, the information and so on the multi-disciplinary overlapping syntheses, its development and the progress rely on and promote the correlation technology development and the progress .Therefore, the integration of machinery main development direction is as follows:3.1 Intellectualized intellectualizations are 21st century integration of machinery technological development important development directions .The artificial intelligence obtains day by day in the integration of machinery constructor's research takes, the robot and the numerical control engine bed intellectualization is the important application .Here said "the intellectualization" is to the machine behavior description, is in the control theory foundation, the absorption artificial intelligence, the operations research, the computer science, the fuzzy mathematics, the psychology, the physiology and the chaos dynamics and so on the new thought, the new method, simulate the human intelligence, enable it to have abilities and so on judgment inference, logical thinking, independent decision-making, obtains the higher control goal in order to .Indeed, enable the integration of machinery product to have with the human identical intelligence, is not impossible, also is nonessential .But, the highperformance, the high speed microprocessor enable the integration of machinery product to have preliminary intelligent or human's partial intelligences, then is completely possible and essential.In the modern manufacture process, the information has become the control manufacture industry the determining factor, moreover is the most active actuation factor .Enhances the manufacture system information-handling capacity to become the modern manufacture science development a key point .As a result of the manufacture system information organization and structure multi-level, makes the information the gain, the integration and the fusion presents draws up the character, information measure multi-dimensional, as well as information organization's multi-level .In the manufacture information structural model, manufacture information uniform restraint, dissemination processing and magnanimous data aspects and so on manufacture knowledge library management, all also wait for further break through.Each kind of artificial intelligence tool and the computation intelligence method promoted the manufacture intelligence development in the manufacture widespread application .A kind based on the biological evolution algorithm computation intelligent agent, in includes thescheduling problem in the combination optimization solution area of technology, receives the more and more universal attention, hopefully completes the combination optimization question when the manufacture the solution speed and the solution precision aspect breaks through the question scale in pairs the restriction .The manufacture intelligence also displays in: The intelligent dispatch, the intelligent design, the intelligent processing, the robot study, the intelligent control, the intelligent craft plan, the intelligent diagnosis and so on are variousThese question key breakthrough, may form the product innovation the basic research system. Between 2 modern mechanical engineering front science different science overlapping fusion will have the new science accumulation, the economical development and society's progress has had the new request and the expectation to the science and technology, thus will form the front science .The front science also has solved and between the solution scientific question border area .The front science has the obvious time domain, the domain and the dynamic characteristic .The project front science distinguished in the general basic science important characteristic is it has covered the key science and technology question which the project actual appeared.Manufacture system is a complex large-scale system, for satisfies the manufacture system agility, the fast response and fast reorganization ability, must profit from the information science, the life sciences and the social sciences and so on the multi-disciplinary research results, the exploration manufacture system new architecture, the manufacture pattern and the manufacture system effective operational mechanism .Makes the system optimization the organizational structure and the good movement condition is makes the system modeling , the simulation and the optimized essential target .Not only the manufacture system new architecture to makes the enterprise the agility and may reorganize ability to the demand response ability to have the vital significance, moreover to made the enterprise first floor production equipment the flexibility and may dynamic reorganization ability set a higher request .The biological manufacture view more and more many is introduced the manufacture system, satisfies the manufacture system new request.The study organizes and circulates method and technique of complicated system from the biological phenomenon, is a valid exit which will solve many hard nut to cracks that manufacturing industry face from now on currently .Imitating to living what manufacturing point is mimicry living creature organ of from the organization, from match more, from growth with from evolution etc. function structure and circulate mode of a kind of manufacturing system and manufacturing process.The manufacturing drives in the mechanism under, continuously by one's own perfect raise on organizing structure and circulating mode and thus to adapt the process of[with] ability for the environment .For from descend but the last product proceed together a design and make a craft rules the auto of the distance born, produce system of dynamic state reorganization and product and manufacturing the system tend automatically excellent provided theories foundation and carry out a condition .Imitate to living a manufacturing to belong to manufacturing science and life science of\"the far good luck is miscellaneous to hand over\", it will produce to the manufacturing industry for 21 centuries huge of influence .翻译机电一体化摘要机电一体化是现代科学技术发展的必然结果,本文简述了机电一体化技术的基本概要和发展背景。

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Considering the point B(0,b) situated at the half of the slide with the length l. After a
certain period of functioning, as a result of the slide wear, the point B will be displaced in the
point B’. In this situation the deviation of the point will be: ∆2 = BB' In order to make the calculation of this deviation 2 cases can be distinguished:
ANALYTICAL MODEL OF CALCULUS FOR INFLUENCE THE TRANSLATION GUIDE WEAR OVER THE MACHINING ACCURACY
ON THE MACHINE TOOL
Assoc.prof.dr.eng. Ivona PETRE, University Valahia from Targoviste, Lecturer dr. eng. Carmen POPA, University Valahia from Targoviste, Lecturer dr. eng. Dumitru DUMITRU, University Valahia from Targoviste,
O
BC
Uxo
A
the bed guide
x
xo
the slide guide
U
Fig.1. Settlement scheme of the mobile slide on a bed-guide
Taking a point A (xo, Uxo) situated at the middle of the mobile slide. The wear of the bed guide in the considered point is Uxo and the function of the bed guide wear Ux. The deviation
a) the point A is not worn U A = 0 ; b) the point A is worn by a size that can be established (measured) UA ≠ 0
l
B(0,b)
B'
Slide
Bed C
O C' M
O'
a
a
A(a,0)
Fig. 2. Assessment scheme of the mobile slide geometry changes
of the point A is considered ∆1 = AC . In order to establish, the coordinates of the point C the normal at the bed guide profile in
the point A is considered a straight line with the slope m that can be determined based on the
xc
=
U
x
U
' x
+x.
The deviation in this case considered:
( ) ( ) ( ) ∆1 =
xc − xA 2 + yc − yA 2 = Ux
1+
U
' x2≤ adm(3)Case 2: the slide guide only is being worn according to a linear variation law (fig.2).
2. Analytic models establishing the error produced by the bed-slides wear In order to establish the quantitative influence of the wear process over the machining
accuracy on a lathe, the following assumptions are made [2]: - the curve of the worn profile of the rigid guide U(x) is considered known at a certain moment assessed by the number of the stress cycles; - the wear on the current stress cycles is neglected compared to the wear produced by all the previous cycles; - the mobile guide wear U1(l) is so produced that the profile of this guide follows continuously the rigid guide profile; based on this assumption it is admitted that the contact is always of the type according to the appropriate distribution of the normal and tangential stress; - the mobile guide is set on the rigid one during the displacement so that normal line to the contact surface of the two profiles is unique; - the wear is a continuous process and is characterized by the thickness of the worn layer, considered as a continuous function onto the guide length and in time.
Keywords: accuracy, machine-tools, surface.
1. Introduction As it has already been known the accuracy of machining each piece depends on a
multitude of factors connected to the technological system (the machine tool, the clamping device, the cutting tool etc) [1, 2, 3]. In the present work, the author’s goal is to establish the size and influence only of the wear of the bed the slide guide over the machining accuracy on machine-tools with use on lather. The size of the guide and (longitudinal) slide wear are important to be known because the change of the slide trajectory due to the wear that occurs in time conditions the dimensional deviations and the quality of the machined parts surface. In order to establish the wear size of the system bed-slide, three distinct situations are being analyzed: 1 – the bed guide only is being worn 2 – the slide guide only is being worn 3 – both guides (bed-slide) are being worn
18
Fiabilitate si Durabilitate - Fiability & Durability no 2(6)/ 2010
Editura “Academica Brâncuşi” , Târgu Jiu, ISSN 1844 – 640X
• Staring from the equation of the straight line that goes through the points AO’ and following the some argument as in case 1, the deviation of the point B’ will be:
Eng. Ciprian MANESCU, University Valahia from Targoviste,
Abstract: The wear of machine tools guides influences favorably to vibrations. As a result of guides wear, the initial trajectory of cutting tools motion will be modified, the generating dimensional accuracy discrepancies and deviations of geometrical shape of the work pieces. As it has already been known, the wear of mobile and rigid guides is determined by many parameters (pressure, velocity, friction length, lubrication, material). The choice of one or another analytic model and/or the experimental model of the wear is depending by the working conditions, assuming that the coupling material is known.The present work’s goal is to establish an analytic model of calculus showing the influence of the translation guides wear over the machining accuracy on machine-tools.
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