机械设计中英文对照外文翻译文献
机械设计中英文外文翻译文献
(文档含英文原文和中文翻译)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 machineryand 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 that used 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．Intermsof 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 ofmachinery 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 of manufacturing 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 to its 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 best choice，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．Forconvenience，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 some practical 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。
机械设计外文文献翻译、中英文翻译
外文原文Mechanical DesignAbstract:A machine is a combination of mechanisms and other components which transforms, transmits. Examples are engines, turbines, vehicles, hoists, printing presses, washing machines, and movie cameras. Many of the principles and methods of design that apply to machines also apply to manufactured articles that are not true machines. The term "mechanical design" is used in a broader sense than "machine design" to include their design. the motion and structural aspects and the provisions for retention and enclosure are considerations in mechanical design. Applications occur in the field of mechanical engineering, and in other engineering fields as well, all of which require mechanical devices, such as switches, cams, valves, vessels, and mixers.Keywords: Mechanical Design mechanisms Design ProcessThe Design ProcessDesigning starts with a need real.Existing apparatus may need improvements in durability, efficiency, weight, speed, or cost. New apparatus may be needed to perform a function previouslydone by men, such as computation, assembly, or servicing. With the objective wholly or partlyIn the design preliminary stage, should allow to design the personnel fully to display the creativity, not each kind of restraint. Even if has had many impractical ideas, also can in the design early time, namely in front of the plan blueprint is corrected. Only then, only then does not send to stops up the innovation the mentality. Usually, must propose several sets of design proposals, then perform the comparison. Has the possibility very much in the plan which finally designated, has used certain not in plan some ideas which accepts.When the general shape and a few dimensions of the several components becomeapparent, analysis can begin in earnest. The analysis will have as its objective satisfactory or superior performance, plus safety and durability with minimum weight, and a competitive cost. Optimum proportions and dimensions will be sought for each critically loaded section, together with a balance between the strengths of the several components. Materials and their treatment will be chosen. These important objectives can be attained only by analysis based upon the principles of mechanics, such as those of static for reaction forces and for the optimum utilization of friction; of dynamics for inertia, acceleration, and energy; of elasticity and strength of materials for stress and deflection; of physical behavior of materials; and of fluid mechanics for lubrication and hydrodynamic drives. The analyses may be made by the same engineer who conceived the arrangement of mechanisms, or, in a large company, they may be made by a separate analysis division or research group. Design is a reiterative and cooperative process, whether done formally or informally, and the analyst can contribute to phases other than his own. Product design requires much research and development. Many Concepts of an idea must be studied, tried, and then either used or discarded. Although the content of each engineering problem is unique, the designers follow the similar process to solve the problems. Product liability suits designers and forced in material selection, using the best program. In the process of material, the most common problems for five (a) don't understand or not use about the latest application materials to the best information, (b) failed to foresee and consider the reasonable use material may (such as possible, designers should further forecast and consider due to improper use products. In recent years, many products liability in litigation, the use of products and hurt the plaintiff accused manufacturer, and won the decision), (c) of the materials used all or some of the data, data, especially when the uncertainty long-term performance data is so, (d) quality control method is not suitable and unproven, (e) by some completely incompetent persons choose materials.Through to the above five questions analysis, may obtain these questions is does not have the sufficient reason existence the conclusion. May for avoid these questions to these questions research analyses the appearance indicating the direction. Although uses the best choice of material method not to be able to avoid having the product responsibility lawsuit, designs the personnel and the industry carries on the choice of material according to the suitable procedure, may greatly reduce the lawsuit the quantity.May see from the above discussion, the choice material people should to the material nature, the characteristic and the processing method have comprehensive and the basic understanding.Finally, a design based upon function, and a prototype may be built. If its tests are satisfactory, the initial design will undergo certain modifications that enable it to be manufactured in quantity at a lower cost. During subsequent years of manufacture and service, the design is likely to undergo changes as new ideas are conceived or as further analyses based upon tests and experience indicate alterations. Sales appeal.Some Rules for DesignIn this section it is suggested that, applied with a creative attitude, analyses can lead to important improvements and to the conception and perfection of alternate, perhaps more functional, economical,and durable products.To stimulate creative thought, the following rules are suggested for the designer and analyst. The first six rules are particularly applicable for the analyst.1. A creative use of need of physical properties and control process.2. Recognize functional loads and their significance.3. Anticipate unintentional loads.4. Devise more favorable loading conditions.5. Provide for favorable stress distribution and stiffness with minimum weight.6. Use basic equations to proportion and optimize dimensions.7. Choose materials for a combination of properties.8. Select carefully, stock and integral components.9. Modify a functional design to fit the manufacturing process and reduce cost.10. Provide for accurate location and noninterference of parts in assembly.Machinery design covers the following contents.1. Provides an introduction to the design process , problem formulation ,safety factors.2. Reviews the material properties and static and dynamic loading analysis ,Including beam , vibration and impact loading.3. Reviews the fundamentals of stress and defection analysis.4. Introduces fatigue-failure theory with the emphasis on stress-life approaches to high-cycle fatigue design, which is commonly used in the design of rotation machinery.5. Discusses thoroughly the phenomena of wear mechanisms, surface contact stresses ,and surface fatigue.6. Investigates shaft design using the fatigue-analysis techniques.7. Discusses fluid-film and rolling-element bearing theory and application8. Gives a thorough introduction to the kinematics, design and stress analysis of spurgears , and a simple introduction to helical ,bevel ,and worm gearing.9. Discusses spring design including compression ,extension and torsion springs.10. Deals with screws and fasteners including power screw and preload fasteners.11. Introduces the design and specification of disk and drum clutches and brakes. Machine DesignThe complete design of a machine is a complex process. The machine design is a creative work. Project engineer not only must have the creativity in the work, but also must in aspect and so on mechanical drawing, kinematics, engineerig material, materials mechanics and machine manufacture technology has the deep elementary knowledge. One of the first steps in the design of any product is to select the material from which each part is to be made. Numerous materials are available to today's designers. The function of the product, its appearance, the cost of the material, and the cost of fabrication are important in making a selection. A careful evaluation of the properties of a. material must be made prior to any calculations.Careful calculations are necessary to ensure the validity of a design. In case of any part failures, it is desirable to know what was done in originally designing the defective components. The checking of calculations (and drawing dimensions) is of utmost importance. The misplacement of one decimal point can ruin an otherwise acceptable project. All aspects of design work should be checked and rechecked.The computer is a tool helpful to mechanical designers to lighten tedious calculations, and provide extended analysis of available data. Interactive systems, based on computer capabilities, have made possible the concepts of computer aided design (CAD) and computer-aided manufacturing (CAM).How does the psychologist frequently discuss causes the machine which the people adapts them to operate. Designs personnel''s basic responsibility is diligently causes the machine to adapt the people. This certainly is not an easy work, because certainly does not have to all people to say in fact all is the most superior operating area and the operating process.Another important question, project engineer must be able to carry on the exchange and the consultation with other concerned personnel. In the initial stage, designs the personnel to have to carry on the exchange and the consultation on the preliminary design with the administrative personnel, and is approved. This generally is through the oral discussion, the schematic diagram and the writing material carries on.If front sues, the machine design goal is the production can meet the human need the product. The invention, the discovery and technical knowledge itself certainly notnecessarily can bring the advantage to the humanity, only has when they are applied can produce on the product the benefit. Thus, should realize to carries on before the design in a specific product, must first determine whether the people do need this kind of product Must regard as the machine design is the machine design personnel carries on using creative ability the product design, the system analysis and a formulation product manufacture technology good opportunity. Grasps the project elementary knowledge to have to memorize some data and the formula is more important than. The merely service data and the formula is insufficient to the completely decision which makes in a good design needs. On the other hand, should be earnest precisely carries on all operations. For example, even if places wrong a decimal point position, also can cause the correct design to turn wrongly.A good design personnel should dare to propose the new idea, moreover is willing to undertake the certain risk, when the new method is not suitable, use original method. Therefore, designs the personnel to have to have to have the patience, because spends the time and the endeavor certainly cannot guarantee brings successfully. A brand-new design, the request screen abandons obsoletely many, knows very well the method for the people. Because many person of conservativeness, does this certainly is not an easy matter. A mechanical designer should unceasingly explore the improvement existing product the method, should earnestly choose originally, the process confirmation principle of design in this process, with has not unified it after the confirmation new idea.外文资料翻译译文机械设计摘要：机器是由机械装置和其它组件组成的。
机械设计过程外文文献翻译、中英文翻译
附录英文Machine design processThe machine is the organization with other components combinations, transforms，the transmission or using the energ，the strength or the movementexample for the beneficial use has the engine．the turbine wheel，the vehicles．the hoist，the printer，the washer and the movie camera Many is suitable tbr themachine design principle and the strength law also is suitable to is not thegenuine machine finished product．the driven wheel hub and the file cabinet tothe measuring appl iance and the nuclear pressure vessel．”Machine designt thisterminology compared to”machine design”more generalized，it including machine design．But regarding certain instruments．1ike uses to determine hot，the mobile line and the volume thermal energy as well as the fluid aspect question needs alone to consider．But when machine design must consider themovement and the structure aspect question as well as preserved and the sealstipulation．In the mechanical engineering domain and all that project domainapplication machine design，all need such as mechanism and so on the svdtch,cam，valve，vessel and mixer．The design beginning tO being true or the imagination need．The existing instrument possibly needs in the durability，the efficiency，the weight，the speedor the cost performs to improve．]he possible need new instrument tO completebefore made the function by the person．1ike t was abundant Assembly or maintenance．After the goal completely or partially determines，the design nextstep is the idea carl complete needs the ffmction the organization and its thearrangement for this，the free hand drawing schematic diagram value is enormous，it not only takes a person idea the recording and the auxiliary．methodwhich if the other people discusses，moreover especially is suitable for with ownidea exchange，also needs to concern as the creative mentality stimulant to thepart widespread knowledge，because a new machine frequently by knew very well each kind of components rearrange or the replace become，perhaps changedthe size and the material．Regardless of after idea process or，a designer callcarry on fast either the sketchy computation or the analysis determines thegeneral size and the feasibility．After about need or may use the spatial meteidea determination，may start according to the proportion picture schematicdiagram．When several components approximate shapes and several sizes come out，the analysis was allowed truly to start．The analysis goal lies in enable it to havesatisfying or the superior performance，as well as will seek the best proportionand the size under the smallest weight security and the durability and thecompetitive cost designer for each essential load bearing section，as well asseveral components intensities balance then choice material and processingmethod．These important goals only have through only then may obtain based on the mechanism analysis，like about reacting force and friction most superioruse principie of statics；About inertia，acceleration and energy principle ofdynamics：About stress and deflection material elasticity and intensity principle；About material physical behavior principle；About lubrication and water poweractuation hydromechanics principle．The analysis may identical engineer whicharranges by the idea machinery do，or makes the analysis in the big company bythe independent analysis department or the research group the result，possibleneed new arrangement and new size．No matter is officially does orunofficialdoes，supposes Japan is relapse and the cooperation process．the analysis staffmay play the role to all stages but not merely is he stage.Some design criteriaIn this part，some people suggested carries on the analysis using the creative manner，this kind of analysis may cause the significant improvement aswell as to the spare product idea and the consummation，the product functionmore．more economical，is perhaps more durable． The creation stage does notneed is at first and the independent stage．Alttlough the analysis staff possiblycertainlv is not responsible for the entire design，but he not meyely is can fromthe numeral proposc wants question correct answer which he soIVes，not merelyis Droduces the stress value，the size or the work limit. He may propose a morewidespread opinion，in order to improvement standard or plan. Because beforethe analysis or in the analysis process，he can familiar install and its the workingcondition．he is in an idea to prepare chooses the plan the rantage Poinl．Best hecan propose the suggestion transfigure eliminates the moment of force or thestress concentration，but was not the permission constructs has the blgsectlonand the excessively many dynamic loads organization should better be he discards his careful desi{；n but is not afterwards saw the machinery discarded.In order to stimulate the creative thought，below suggested designs thepersonnel and the analysis staff uses the criterion.The first 6 criteria especially are suitable for the analysis staff,although he possibly involves to possesses this l o items.1．Creatively the use needs the physical performance and the control doesnot need．2．Knows the practical load and its the importance.3．D00s not consider the function load in advance.4．Invents the more advantageous loading environment.5．Provides the minimurn weight the most advantageous stress distributionand the rigidity．6．uses the fundamental equation computation proportion and causes thesize optimization．7．The selection material obtains the perlbrmance combination．8．In between spare parts and integrated components carefid choice． 9．Revisions functional design adapts the production process and reduces thecost．10．In the consideration assembly causes the part pintpointing and mutuallydoes not disturb．Designs the personnel to have in such domain，like the statics，the inematics，dynamics and the materials mechanics have the good accomplishment，in addition．but also must familiar make the material and themanufacture craft．Designs the personnel to have to be able to combine allcollrelations the fact，carries on teaches Wei．the manufacture schematic diagramand the charting comes the manufacture request totransmit the workshop． Any product design one of first step of work is the choice uses in to makeeach part the material．Today design personnel may obtain innumerably．When choice，the product function，the outward appearance，the material cost and theproduction cost very are all important．Before any computation must carefullyappraise the material the performance．It is the necessary careful computation toguarantee the design the validity The computation ever does not appear on thechart，but is saved by ten each kind of reason．Once any part expires，had makeclear when is designing at first this had the flaw the components has made any；Moreover，。
机械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(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。
机械设计类英文文献及翻译
The Sunflower Seed Huller and Oil PressBy Jeff Cox-- from Organic Gardening, April 1979, Rodale PressIN 2,500 SQUARE FEET, a family of four can grow each year enough sunflower seed to produce three gallons of homemade vegetable oil suitable for salads or cooking and 20 pounds of nutritious, dehulled seed -- with enough broken seeds left over to feed a winter's worth of birds.The problem, heretofore, with sunflower seeds was the difficulty of dehulling them at home, and the lack of a device for expressing oil from the seeds. About six months ago, we decided to change all that. The job was to find out who makes a sunflower seed dehuller or to devise one if none were manufactured. And to either locate a home-scale oilseed press or devise one. No mean task.Our researches took us from North Dakota -- hub of commercial sunflower activity in the nation -- to a search of the files in the U.S. Patent Office, with stops in between. We turned up a lot of big machinery, discovered how difficult it is to buy really pure, unrefined vegetable oils, but found no small-scale equipment to dehull sunflowers or press out their oil. The key to success, however, was on our desk the whole time. In spring 1977, August Kormier had submitted a free-lance article describing how he used a Corona grain mill to dehull his sunflower seeds, and his vacuum cleaner exhaust hose to blow the hulls off the kernels. A second separation floated off the remaining hulls, leaving a clean product. We'd tried it, but because some kernels were cracked and the process involved drying, we hadn't been satisfied. Now we felt the best approach was to begin again with what we learned from Mr. Kormier and refine it.Staff Editor Diana Branch and Home Workplace Editor Jim Eldon worked with a number of hand- and electric-powered grain mills. While the Corona did a passable job, they got the best results with the C.S. Bell #60 hand mill and the Marathon Uni Mill, which is motor-driven. "I couldn't believe my eyes the first time I tried the Marathon," Diana says. "I opened the stones to 1/8th inch, and out came a bin full of whole kernels and hulls split right at the seams. What a thrill that was!"She found that by starting at the widest setting,and gradually narrowing the opening, almost every seed was dehulled. The stones crack the hulls open, then rub them to encourage the seed away from the fibrous lining. The Bell hand mill worked almost as well. "As long as the stones open at least as wide as the widest unhulled seed, any mill will work," she says.Because the seed slips through the mill on its flat side, grading is an important step to take before dehulling. We made three sizing boxes. Thefirst is 1/4-inch hardware cloth [wire screen]. The second is two layers of1/4-inch cloth, moved slightly apart to narrow the opening in one direction, and the third is two layers of screen adjusted to make a still-smaller opening. Since the smallest unhulled seeds are about the size of the largest hulled kernels, the grading step prevents these undersized seeds from passing through unhulled. Processed together at a closer setting, the smallest seeds hulled out.Jim Eldon's workshop is littered with strange-looking pieces of apparatus. They represent initial attempts to build a workable winnowing box, using Kormier's vacuum exhaust idea for a source of air. Jim, Fred Matlack and Diana finally made a box with a Plexiglas front, through which they could observe what was happening.They cut a hole in the back of the box with a sliding cover to regulate the air pressure, and fiddled with various arrangements of baffles. The result was a stream of hulls exiting through one hole while the kernels fell to the bottom of the box. Now they were ready to try a five-pound sample of unhulled sunflower seeds to see how much they could recover.The five pounds were graded and dehulled, then winnowed. We got about one hull for every ten kernels in the final, winnowed product. These are easily picked out. They usually contain kernels still held behind the fibrous strings of the hull. Their weight prevents them from blowing out with the empty hulls. We found that bug-eaten seeds do blow away with the chaff, which was a bonus for cleanliness of the final product. Toss the hulls to the birds, who will find broken seeds among them.Starting with 80 ounces of unhulled seed, we ended up with 41-1/4 ounces of edible whole seeds, 1.8 ounces of damaged seeds suitable for animal feed, and 36.6 ounces of hulls. It took us about an hour. Notbad.Sunflower seeds store perfectly in the hulls, but they deteriorate more rapidly when shelled out. The grain mill dehuller and winnowing box give the gardener a way to have the freshest possible seeds for eating at all times of the year. With the construction of one more piece of equipment -- the oil press -- he can have absolutely fresh, unrefined, polyunsaturated sunflower oil for salads, mayonnaise and cooking.Most light, refined vegetable oils have been extracted using hexane, a form of naphtha. The oil is then heated to boil off the hexane. Lye is dumped into it. It's washed with steam, then heated to remove odors and taste before being laced with preservatives and stabilizers. It may feel oily in the mouth, but you might as well taste air. No so with fresh-made sunflower oil -- it's deliciously yet subtly nutty in flavor, adding unsurpassed flavor to salads.There's good reason to believe that sunflower oil may become the #1 vegetable oil in the U.S. in a few years. It's already #1 in health-conscious Europe. Corn oil has already caught on here for health reasons, and sunflower oil is so much better. Sunflower oil's 70 percent polyunsaturate is just under safflower, with corn oil bringing up the rear with 55 percent. And sunflowers yield 40 percent oil, soybeans only 20 percent.Our oil press isrelatively simple, but it must be welded together. Check the construction directions for details. The press consists of a welded tubular frame which accepts a three-ton hydraulic jack. You may already have one. If not, it can be purchased at most auto and hardware stores for about $16. A metal canister with holes drilled in its sides and one end welded shut holds the mashed sunflower seeds. A piston is inserted in the canister and then inverted and slipped over a pedestal on the frame. The jack is set in place, and the pressure gradually increased over half an hour. The oil drips from the sides of the canister into a tray -- the bottom of a plastic jug slipped over the pedestal works fine -- which empties the oil into a cup. You can filter the oil with a coffee filter to remove pieces of seed and other fine particles that would burn if the oil were used for cooking. If it's for salads or mayonnaise, there's no need to filter it.We first tried using "confectionary" sunflower seeds for oil. These are the regular eating kernels we're used to seeing. They give less than half as much oil as the oilseed types of sunflower. Although you can use confectionary types such as MAMMOTH RUS- SIAN for oil, don't expect to get more than an ounce and a half from a pound of seed. Oilseed produces three or more ounces of oil from a pound of seed and is well worth planting along with confectionary-type seeds. Oilseed has another big advantage -- to prepare it, you can put the whole, unhulled seed into a blender and whiz it until it forms a fine meal, while confectionary seeds must be dehulled first. The entire sequence of grading, dehulling and winnowing is avoided with oilseed.Oil types produce about a tenth of a pound of seed per head in commercial production. Gardeners, with their better soil and care, invariably do better than that. Our conservative estimate is that 1,280 plants will be enough for three gallons of oil. Spaced one foot apart in rows two feet apart, 1,280 oilseed plants will take a space 40-by-56 feet, or 80-by-28 if you want a more rectangular patch to face south.We worked in pound batches, since the canister just holds one pound of mash. After blending, we heated it to 170 degrees F. (77 deg C) by placing it in a 300-degree F. (149 deg C) oven and stirring it every five minutes for 20 minutes. Heating gets the oil flowing and doubles the yield of oil. In case you're wondering,"cold-pressed" oils sold commercially are also heated, and some are subjected to the entire chemical process. The term has no firm meaning within the industry, according to the literature we've surveyed.Heating does not change the structure of fats. It will not turn polyunsaturated fats into saturated fats. In fact, Dr. Donald R. Germann in his book, "TheAnti-Cancer Diet", says that "... an unsaturated fat must be heated to high temperatures -- above 425 degrees F. or 200 degrees C. -- at least 8 or 10 times before any shift toward saturation occurs..." Dean C. Fletcher, Ph.D., of the American Medical Association Department of Foods and Nutrition in Chicago, says, "It's true that either high temperature or repeated heatingdoes change the nature of some of the unsaturated oil molecules. (But) the flavor of the oil changes as these chemical changes occur, spoiling its taste. This effect is probably more profound than any of the physiological changes the altered oil might produce within the body."From 500 gm. of heated mash, we pressed 89 gm. of oil, 89 percent of the entire amount available and twice as much as we could press from unheated oil! The decision is up to you whether or not to heat the mash, but that extra 50 percent seems like an awful lot, especially when the whole technique is so labor intensive. The oil should be stored in the refrigerator, and it's probably best to use it within a month, since it has no preservatives. Mayonnaise made with such fresh oils should be kept refrigerated and used within two weeks. The leftover cake, still containing 50 percent of its oil, is a nutritious addition to your dishes, and makes excellent feed for animals or winter birds. Store the pressed cake in the freezer.We're talking then about a sunflower patch with two kinds of plants -- confectionary such as MAMMOTH RUSSIAN and oilseed such as PEREDOVIK. The oilseed plants should be grown 12 inches apart in rows two feet apart. Four average confectionary heads yield about a pound of unhulled seed. You'll need about 35 pounds of unhulled seed, or 140plants-worth, to yield 20 pounds of hulled kernels, about what a family of four will use in a year. That many plants can be grown in an area 26-by-10 feet. That's 260 square feet. Put that together with the 2,240 square feet for the oilseed sunflowers, and you need a patch about 2,500 square feet -- 25 100-foot rows -- to keep yourself supplied year-round with super nutrition and unsurpassable taste.Winnowing Machine For Sunflower SeedsThe winnowing machine operates on the age-old principle of blowing the chaff away from the heavy grain with a controlled current of air.The unit uses a household or shop-type vacuum cleaner for its air supply. A vacuum cleaner was used as a power source because it can supply a large volume of air over an extended period of time, and most homes and farms have a vacuum cleaner.A cloth bag has been attached to the chaff chute to catch the chaff as it is separated from the seed. The bag allows the hulls to be collected and greatly reduces the amount of waste material normally blown into the air by conventional systems.The unit has been constructed in such a way that the cloth bag and cleaner box can be placed inside the seed box, making a compact package for storage.Tools Required1. Table Saw2. Drill Press3. Band Saw4. Saber SawProcedure (cleaner box)1 . Cut out the two sides of the cleaner box from 1/4-inch plywood.2. Cut out the six interior pieces of the cleaner box from 3/4 x 3-1/2-inch select pine.3. Assemble the cleaner box elements with glue and nails.4. Cut four 1/4-inch square strips of pine four inches long.5. Glue the strips around the end of the chaff chute.6. Sand all surfaces and edges.7. Finish with clear lacquer finish.Procedure (seed box)1. Cut two pieces of pine /34" x 5 /12 x 15 inches for the sides.2. Cut two pieces of pine 3/4 x 5-1/2 x inches for the top and bottom.3. Plow a /14 x 1/4 groove for the front and back panels in all four pieces.4. Rip the top board to 5 inches so that the front panel can slide into the grooves in the side boards.5. Rabbet both ends of each 15-inch side piece to accept the top and bottom boards.6. Drill a hole in the left side board 2-1/2 inches from the top. The size of the hole is determined by the vacuum cleaner hose fitting.7. Cut a 3-1/4 x 4 inch hole in the top 1/2 inch from the right end. This hole will accept the cleaner box.8. Cut two pieces of pine for the baffle.9. Drill two 1-inch holes in the bottom of the baffle box.10. Cut a piece of 1/4 x 8-1/2 x 14 inch plywood for the back panel.11. Cut a 3-inch hole, centered 1-7/8 inches from the top and left sides of the plywood back.12. Assemble the sides, baffles, top, bottom, and back panel with glue and nails.13. Cut an 8-7/16 x 15-3/4-inch piece of Plexiglas for the front.14. Cut a one-inch radius on the top corners of the front.and sand the edges.15. Drill a one-inch thumb hole centered 7/8 inch from the top edge.16. Cut a 3-1/2-inch disk of 1/4-inch plywood for the vent cover.17. Drill a 3/16-inch hole 3/8 inch from the edge of the disk.18. Mount the disk over the vent with a #10 x 1-inch screw.19. Sand all surfaces and edges of the, box.20. Finish with clear lacquer finish.MaterialsCleaner Box2 -- 7-3/4 x 7-1/2 x 3/4" plywood (sides)6 -- 3/4 x 3-1/2 x 24" for all members (baffles)4 -- 1/4 x 1/4 x 4" pine (chute cleats)22 -- 1" x 18 ga. headed nailsWhite vinyl glueClear lacquer finishSeed Box2 -- 3/4' x 5-1/2 x 15" select pine (sides)2 -- 3/4 x 5-1/2 x 8-1/2" select pine (top and bottom)1 -- 3/4 x 3-1/2 x 4-1/2" select pine (baffle)1 -- 3/4 x 4-1/2 x 4-1/2" select pine (baffle)1 -- 1/4 x 8-1/2 x 14" plywood (back)1 -- 1/4 x 3-1/2" dia. plywood (control valve)1 -- 1/4' x 8-7/16 x 15-1/4" Plexiglas (front)1 - #10 x 1" flat head screw18 - 4d finish nailsWhite vinyl glueClear lacquer finish1 -- 17 x 31" cloth laundry bagSunflower Seed Oil PressThe press was designed so that homesteaders can produce sunflower oil from their own seeds. The oil can be pressed as is or heated to 170 degrees F., which doubles oil yield.Both methods require the seed to be ground to fine powder. If you are pressing the oil seed variety, a meat grinder or electric blender will do an excellent job of grinding the seed. The confectionary type of seed will require the seed to be hulled and winnowed before it is ground. A food mill with the stones set at the coarse setting can be used to accomplish this step. The ground kernels are placed in the cylinder with the piston closing the bottom portion of the cylinder.The cylinder is mounted in the press frame and a three-ton hydraulic jack is used to supply the pressure.Because of the great pressures created by the hydraulic jack, it is important that the frame be properly constructed and firmly mounted to the work surface before the pressing operation begins. The following instructions can be given to a welder.Tools Required1. Power Hacksaw2. Metal Band Saw3. Metal Lathe4. Drill Press5. Belt or Disk Grinder6. Arc Welder7. Hand ClampsProcedure (Frame)1. Cut two pieces of 1-3/4" O.D. x 1-3/8" I.D. x 24-1/2 inch long tubing for the uprights.2. Cut one piece of 1-3/4" O.D. x 1-3/8" I.D. x 6-1/2 inch long tubing for the center tube.3. Cut one 3/4" x 2-3/4 x 5-1/2 inch steel bar for the top cross member.4. Cut two pieces of 1-3/4 x 1-3/4 x 8 inch angle iron for the base members.5. Drill two 9/32-inch holes in each base member 1/2 inch from the outer edges.6. Weld the base members, tubes and cross member together as per the drawing.7. Grind all edges to remove any burrs.8. Paint the frame.9. If a mounting board is desired, cut a piece of pine 1-1/4 x 6-1/2 x 12 inches long.10. Center the frame on the board and mark the location of the four mounting holes.11. Drill four 7/8-inch holes 1/4-inch deep to accept the T-nuts.12. Drill four 5/16-inch holes through the mounting board using the same centers created by the 7/8-inch holes.13. Round the edges of the base and sand all surfaces.14. Install four 1/4-20 T-nuts.15. Finish the base with clear lacquer finish.16. Assemble the base to the frame using four 1/4-20 x 1-1/4-inch round head bolts.Procedure (Cylinder)1. Cut a piece of 3-1/2" O.D. x 3-1/4" I.D. tubing 5-3/8 inches long.2. Face both ends on the lathe.3. Cut out a 3-1/2-inch round disk from 1/4-inch plate steel.4. Weld the disk to one end of the tube.5. Drill a series of 3/32-inch holes around the side of the tube on 1/2-inch centers.6. Remove all burrs on the inside and outside of the tube.Procedure (Piston)1. Cut out a 3-3/8-inch disk of 1/4-inch plate steel.2. Cut a 1-3/8" O.D. x 1-1/8" I.D. piece of tubing 1-1/8 inches long.3. Face both ends of the tube.4. Weld the tube in the center of the 3-3/8-inch disk. All welds should be made on the inside of the tube.5. Mount the piston in the lathe and turn the disk to fit the inside diameter of the cylinder. This will be about 3-15/64 inches in diameter.6. Remove any sharp edges.Procedure (Collector Ring)1. Cut the bottom out of a one-gallon plastic bottle. The cut line should be approximately 1-1/2 inches from the bottom of the bottle.2. Make a 1/8 x 1 inch slot at one edge of the bottom outside ring. This will allow the oil to pour into a receiving cup.3. Cut a 1-3/4-inch hole in the center of the bottom, so that the unit will fit over the center tube in the frame.MaterialsFrame2 -- 1-3/4 O.D. x 1-3/8 I.D. x 24-1/2" long H.R.S. (frame tubes)1 -- 1-3/4 O.D. x 1-3/8 I.D. x 6-1/2 inch long H.R.S. (center tube)1 -- 3/4 x 2-3/4 x 5-1/2" flat bar H.R.S. (top cross member)2 -- 1-3/4 x 1-3/4 x 8" angle iron H.R.S. (base members)1 -- 1-1/4 x 6-1/2 x 12" #2 white pine (wood base)4 -- 1/4-20 x 1-1/4 R.H. mounting bolts4 -- 1/4-20 T-nutsBlack enamel for frame (finishing material)Clear lacquer finish for wood base3 -- 1/8" dia. welding rodsCylinder1 -- 1/4 x 3-1/2" dia. C.R.S. disk (top)1 -- 3-1/2 O.D. x 3-1/4 I.D. C.R.S. tube (cylinder)1 -- 1/8 dia. welding rodPiston1 -- 1/4 x 3-3/8 D.A. C.R.S. disk (piston top)1 -- 1-1/4 O.D. x 1 I.D. x 1" long H.R.S. (piston tube)1 -- 1/8 dia. welding rodCollector Ring1 -- Bottom from a one-gallon plastic bottle (oil collector ring)葵花籽脱壳机和油压机由Jeff考克斯-从有机园艺，1979年4月，罗代尔新闻2,500平方尺，一个四口之家每年可以长到足以产生三种葵花籽国产蔬菜沙拉或烹调油和20磅的营养丰富，适合脱皮加仑种子 - 与遗留养活一个冬天的产值，破碎的种子鸟类。
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。
机械设计外文翻译---工艺规程制订与并行工程
外文文献原稿和译文原稿Process Planning and Concurrent EngineeringT. Ramayah and Noraini IsmailABSTRACTTh e product design is the plan for the product and its components and subassemblies. To convert the product design into a physical entity, a manufacturing plan is needed. The activity of developing such a plan is called process planning. It is the link between product design and manufacturing. Process planning involves determining the sequence of processing and assembly steps that must be accomplished to make the product. In the present chapter, we examine processing planning and several related topics.Process PlanningPr ocess planning involves determining the most appropriate manufacturing and assembly processes and the sequence in which they should be accomplished to produce a given part or product according to specifications set forth in the product design documentation. The scope and variety of processes that can be planned are generally limited by the available processing equipment and technological capabilities of the company of plant. Parts that cannot be made internally must be purchased from outside vendors. It should be mentioned that the choice of processes is also limited by the details of the product design. This is a point we will return to later.Process planning is usually accomplished by manufacturing engineers. The processplanner must be familiar with the particular manufacturing processes available in the factory and be able to interpret engineering drawings. Based on the planner’s knowledge, skill, and experience, the processing steps are developed in the most logical sequence to make each part. Following is a list of the many decisions and details usually include within the scope of process planning..nterpretation of design drawings.The part of product design must be analyzed (materials, dimensions, tolerances, surface finished, etc.) at the start of the process planning procedure..Process and sequence.The process planner must select which processes are required and their sequence. A brief description of processing steps must be prepared..Equipment selection. In general, process planners must develop plans that utilize existing equipment in the plant. Otherwise, the component must be purchased, or an investment must be made in new equipment..Tools, dies, molds, fixtures, and gages.The process must decide what tooling is required for each processing step. The actual design and fabrication of these tools is usually delegated to a tool design department and tool room, or an outside vendor specializing in that type of tool is contacted..Methods analysis.Workplace layout, small tools, hoists for lifting heavy parts, even in some cases hand and body motions must be specified for manual operations. The industrial engineering department is usually responsible for this area..Work standards.Work measurement techniques are used to set time standards for each operation..Cutting tools and cutting conditions.These must be specified for machining operations, often with reference to standard handbook recommendations.Process planning for partsO r individual parts, the processing sequence is documented on a form called a route sheet. Just as engineering drawings are used to specify the product design, route sheets are used to specify the process plan. They are counterparts, one for product design, the other for manufacturing.Typical processing sequence to fabricate an individual part consists of: (1) a basic process, (2) secondary processes, (3) operations to enhance physical properties, and (4) finishing operations. A basic process determines the starting geometry of the work parts. Metal casting, plastic molding, and rolling of sheet metal are examples of basic processes. The starting geometry must often be refined by secondary processes, operations that transform the starting geometry (or close to final geometry). The secondary geometry processes that might be used are closely correlated to the basic process that provides the starting geometry. When sand casting is the basic processes, machining operations are generally the second processes. When a rolling mill produces sheet metal, stamping operations such as punching and bending are the secondary processes. When plastic injection molding is the basic process, secondary operations are often unnecessary, because most of the geometric features that would otherwise require machining can be created by the molding operation. Plastic molding and other operation that require no subsequent secondary processing are called net shape processes. Operations that require some but not much secondary processing (usually machining) are referred to as near net shape processes. Some impression die forgings are in this category. These parts can often be shaped in the forging operation (basic processes) so that minimal machining (secondary processing) is required.The geometry has been established, the next step for some parts is to improve their mechanical and physical properties. Operations to enhance properties do not alter the geometry of the part; instead, they alter physical properties. Heat treating operations on metal parts are the most common examples. Similar heating treatments are performed on glass to produce tempered glass. For most manufactured parts, these property-enhancing operations are not required in the processing sequence.Finally finish operations usually provide a coat on the work parts (or assembly) surface. Examples included electroplating, thin film deposition techniques, and painting. The purpose of the coating is to enhance appearance, change color, or protect the surface from corrosion, abrasion, and so forth. Finishing operations are not required on many parts; for example, plastic molding rarely require finishing. Whenfinishing is required, it is usually the final step in the processing sequence. Processing Planning for AssembliesTh e type of assembly method used for a given product depends on factors such as: (1) the anticipated production quantities; (2) complexity of the assembled product, for example, the number of distinct components; and (3) assembly processes used, for example, mechanical assembly versus welding. For a product that is to be made in relatively small quantities, assembly is usually performed on manual assembly lines. For simple products of a dozen or so components, to be made in large quantities, automated assembly systems are appropriate. In any case, there is a precedence order in which the work must be accomplished. The precedence requirements are sometimes portrayed graphically on a precedence diagram.Process planning for assembly involves development of assembly instructions, but in more detail .For low production quantities, the entire assembly is completed at a single station. For high production on an assembly line, process planning consists of allocating work elements to the individual stations of the line, a procedure called line balancing. The assembly line routes the work unit to individual stations in the proper order as determined by the line balance solution. As in process planning for individual components, any tools and fixtures required to accomplish an assembly task must be determined, designed, built, and the workstation arrangement must be laid out. Make or Buy DecisionAn important question that arises in process planning is whether a given part should be produced in the company’s own factory or purchased from an outside vendor, and the answer to this question is known as the make or buy decision. If the company does not possess the technological equipment or expertise in the particular manufacturing processes required to make the part, then the answer is obvious: The part must be purchased because there is no internal alternative. However, in many cases, the part could either be made internally using existing equipment, or it could be purchasedexternally from a vendor that process similar manufacturing capability.In our discussion of the make or buy decision, it should be recognized at the outset that nearly all manufactures buy their raw materials from supplies. A machine shop purchases its starting bar stock from a metals distributor and its sand castings from a foundry. A plastic molding plant buys its molding compound from a chemical company. A stamping press factory purchases sheet metal either fro a distributor or direct from a rolling mill. Very few companies are vertically integrated in their production operations all the way from raw materials, it seems reasonable to consider purchasing at least some of the parts that would otherwise be produced in its own plant. It is probably appropriate to ask the make or buy question for every component that is used by the company.Here are a number of factors that enter into the make or buy decision. One would think that cost is the most important factor in determining whether to produce the part or purchase it. If an outside vendor is more proficient than the company’s own plant in the manufacturing processes used to make the part, then the internal production cost is likely to be greater than the purchase price even after the vendor has included a profit. However, if the decision to purchase results in idle equipment and labor in the company’s own plant, then the apparent advantage of purchasing the part may be lost. Consider the following example make or Buy Decision.The quoted price for a certain part is $20.00 per unit for 100 units. The part can be produced in the company’s own plant for $28.00. The components of making the part are as follows:Unit raw material cost = $8.00 per unitDirect labor cost =6.00 per unitLabor overhead at 150%=9.00 per unitEquipment fixed cost =5.00 per unit________________________________Total =28.00 per unitShould the component by bought or made in-house?Solution: Although the vendor’s quote seems to favor a buy decision, let us consider the possible impact on plant operations if the quote is accepted. Equipment fixed cost of $5.00 is an allocated cost based on investment that was already made. If the equipment designed for this job becomes unutilized because of a decision to purchase the part, then the fixed cost continues even if the equipment stands idle. In the same way, the labor overhead cost of $9.00 consists of factory space, utility, and labor costs that remain even if the part is purchased. By this reasoning, a buy decision is not a good decision because it might be cost the company as much as $20.00+$5.0+$9.00=$34.00 per unit if it results in idle time on the machine that would have been used to produce the part. On the other hand, if the equipment in question can be used for the production of other parts for which the in-house costs are less than the corresponding outside quotes, then a buy decision is a good decision.ake or buy decision are not often as straightforward as in this example. A trend in recent years, especially in the automobile industry, is for companies to stress the importance of building close relationships with parts suppliers. We turn to this issue in our later discussion of concurrent engineering.Computer-aided Process PlanningHere is much interest by manufacturing firms in automating the task of process planning using computer-aided process planning (CAPP) systems. The shop-trained people who are familiar with the details of machining and other processes are gradually retiring, and these people will be available in the future to do process planning. An alternative way of accomplishing this function is needed, and CAPPsystems are providing this alternative. CAPP is usually considered to be part of computer-aided manufacturing (CAM). However, this tends to imply that CAM is a stand-along system. In fact, a synergy results when CAM is combined with computer-aided design to create a CAD/CAM system. In such a system, CAPP becomes the direct connection between design and manufacturing. The benefits derived from computer-automated process planning include the following: .Process rationalization and standardization. Automated process planning leads to more logical and consistent process plans than when process is done completely manually. Standard plans tend to result in lower manufacturing costs and higher product quality..Increased productivity of process planner. The systematic approach and the availability of standard process plans in the data files permit more work to be accomplished by the process planners..Reduced lead time for process planning. Process planner working with a CAPP system can provide route sheets in a shorter lead time compared to manual preparation..Improved legibility. Computer-prepared rout sheets are neater and easier to read than manually prepared route sheets..Incorporation of other application programs. The CAPP program can be interfaced with other application programs, such as cost estimating and work standards.Computer-aided process planning systems are designed around two approaches. These approaches are called: (1) retrieval CAPP systems and (2) generative CAPP systems .Some CAPP systems combine the two approaches in what is known as semi-generative CAPP.Concurrent Engineering and Design for ManufacturingOncurrent engineering refers to an approach used in product development in which the functions of design engineering, manufacturing engineering, and other functions are integrated to reduce the elapsed time required to bring a new product to market. Also called simultaneous engineering, it might be thought of as the organizationalProduct design Manufacturing engineering and process planning Production and assembly The “wall” bet ween design and manufacturing Product launch time, traditional design/manufacturing cycle Difference in product launch time (a)Traditional product development cycle Product design Sales and marketing Quality engineering Vendors Manufacturing engineering and process planning Production and assemblyProduct laugh time,concurrent engineering(b) Product development using concurrent engineeringcounterpart to CAD/CAM technology. In the traditional approach to launching a new product, the two functions of design engineering and manufacturing engineering tend to be separated and sequential, as illustrated in Fig.(1).(a).The product design department develops the new design, sometimes without much consideration given to the manufacturing capabilities of the company, There is little opportunity for manufacturing engineers to offer advice on how the design might be alerted to make it more manufacturability. It is as if a wall exits between design and manufacturing. When the design engineering department completes the design, it tosses the drawings and specifications over the wall, and only then does process planning begin.g.(1). Comparison: (a) traditional product development cycle and (b) product development using concurrent engineeringContrast, in a company that practices concurrent engineering, the manufacturing engineering department becomes involved in the product development cycle early on, providing advice on how the product and its components can be designed to facilitate manufacture and assembly. It also proceeds with early stages of manufacturing planning for the product. This concurrent engineering approach is pictured in Fig.(1).(b). In addition to manufacturing engineering, other function are also involved in the product development cycle, such as quality engineering, the manufacturing departments, field service, vendors supplying critical components, and in some cases the customer who will use the product. All if these functions can make contributions during product development to improve not only the new product’s function and performance, but also its produceability, inspectability, testability, serviceability, and maintainability. Through early involvement, as opposed to reviewing the final product design after it is too late to conveniently make any changes in the design, the duration of the product development cycle is substantially reduced.On current engineering includes several elements: (1) design for several manufacturing and assembly, (2) design for quality, (3) design for cost, and (4) design for life cycle. In addition, certain enabling technologies such as rapid prototyping, virtual prototyping, and organizational changes are required to facilitate the concurrent engineering approach in a company.Design for Manufacturing and AssemblyIt has been estimated that about 70% of the life cycle cost of a product is determined by basic decisions made during product design. These design decisions include the material of each part, part geometry, tolerances, surface finish, how parts are organized into subassemblies, and the assembly methods to be used. Once these decisions are made, the ability to reduce the manufacturing cost of the product is limited. For example, if the product designer decides that apart is to be made of analuminum sand casting but which processes features that can be achieved only by machining(such as threaded holes and close tolerances), the manufacturing engineer has no alternative expect to plan a process sequence that starts with sand casting followed by the sequence of machining operations needed to achieve the specified features .In this example, a better decision might be to use a plastic molded part that can be made in a single step. It is important for the manufacturing engineer to be given the opportunity to advice the design engineer as the product design is evolving, to favorably influence the manufacturability of the product.Erm used to describe such attempts to favorably influence the manufacturability of a new product are design for manufacturing (DFM) and design for assembly(DFA). Of course, DFM and DFA are inextricably linked, so let us use the term design for manufacturing and assembly (DFM/A). Design for manufacturing and assembly involves the systematic consideration of manufacturability and assimilability in the development of a new product design. This includes: (1) organizational changes and (2) design principle and guidelines..Organizational Changes in DFM/A.Effective implementation of DFM/A involves making changes in a company’s organization structure, either formally or informally, so that closer interaction and better communication occurs between design and manufacturing personnel. This can be accomplished in several ways: (1)by creating project teams consisting of product designers, manufacturing engineers, and other specialties (e.g. quality engineers, material scientists) to develop the new product design; (2) by requiring design engineers to spend some career time in manufacturing to witness first-hand how manufacturability and assembility are impacted by a product’s design; and (3)by assigning manufacturing engineers to the product design department on either a temporary or full-time basis to serve as reducibility consultants..Design Principles and Guidelines.DFM/A also relies on the use of design principles and guidelines for how to design a given product to maximize manucturability and assembility. Some of these are universal design guidelines that can be applied to nearly any product design situation. There are design principles thatapply to specific processes, and for example, the use of drafts or tapers in casted and molded parts to facilitate removal of the part from the mold. We leave these more process-specific guidelines to texts on manufacturing processes.The guidelines sometimes conflict with one another. One of the guidelines is to “simplify part geometry, avoid unnecessary features”. But another guideline in the same table states that “spe cial geometric features must sometimes be added to components” to design the product for foolproof assembly. And it may also be desirable to combine features of several assembled parts into one component to minimize the number of parts in the product. In these instances, design for part manufacture is in conflict with design for assembly, and a suitable compromise must be found between the opposing sides of the conflict.译文工艺规程制订与并行工程T. Ramayah and Noraini Ismail摘要产品设计是用于产品，及它的部件装配的计划。
机械设计外文文献翻译、中英文翻译
机械设计外文文献翻译、中英文翻译unavailable。
The first step in the design process is to define the problem and XXX are defined。
the designer can begin toXXX evaluated。
and the best one is XXX。
XXX.Mechanical DesignA XXX machines include engines。
turbines。
vehicles。
hoists。
printing presses。
washing machines。
and XXX and methods of design that apply to XXXXXX。
cams。
valves。
vessels。
and mixers.Design ProcessThe design process begins with a real need。
Existing apparatus may require XXX。
efficiency。
weight。
speed。
or cost。
while new apparatus may be XXX。
To start。
the designer must define the problem and XXX。
ideas and concepts are generated。
evaluated。
and refined until the best one is XXX。
XXX.XXX。
assembly。
XXX.During the preliminary design stage。
it is important to allow design XXX if some ideas may seem impractical。
they can be corrected early on in the design process。
机械设计理论外文翻译、中英文翻译、外文文献翻译
外文原文：Machine design theoryThe machine design is through designs the new product or improves the old product to meet the human need the application technical science. It involves the project technology each domain, mainly studies the product the size, the shape and the detailed structure basic idea, but also must study the product the personnel which in aspect the and so on manufacture, sale and use question.Carries on each kind of machine design work to be usually called designs the personnel or machine design engineer. The machine design is a creative work. Project engineer not only must have the creativity in the work, but also must in aspect and so on mechanical drawing, kinematics, engineering material, materials mechanics and machine manufacture technology has the deep elementary knowledge.If front sues, the machine design goal is the production can meet the human need the product. The invention, the discovery and technical knowledge itself certainly not necessarily can bring the advantage to the humanity, only has when they are applied can produce on the product the benefit. Thus, should realize to carries on before the design in a specific product, must first determine whether the people do need this kind of productThe machine design must regard as 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 personnel design 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 bringssuccessfully. A brand-new design, the request screen abandons absolutely many, knows very well the method for the people. Because many person of conservativeness does this certainly is not an easy matter. A mechanical designer should unceasingly explore the improvement existing product the method, should earnestly choose originally, the process confirmation principle of design in this process, with has not unified it after the confirmation new idea.Newly designs itself can have the question occurrence which many flaws and has not been able to expect, only has after these flaws and the question are solved, can manifest new goods come into the market the product superiority. Therefore, a performance superior product is born at the same time, also is following a higher risk. Should emphasize, if designs itself does not request to use the brand-new method, is not unnecessary merely for the goal which transform to use the new method.In the design preliminary stage, should allow to design the personnel fully to display the creativity, not each kind of restraint. Even if has had many impractical ideas, also can in the design early time, namely in front of the plan blueprint is corrected. Only then, only then does not send to stops up the innovation the mentality. Usually, must propose several sets of design proposals, them perform the comparison. Has the possibility very much in the plan which finally designated, has used certain not in plan some ideas which accepts.How does the psychologist frequently discuss causes the machine which the people adapts them to operated. Design personnel's basic responsibility is diligently causes the machine to adapt the people. This certainly is not an easy work, because certainly does not have to all people to say in fact all is the most superior operating area and the operating process.Another important question, project engineer must be able to carry on the exchange and the consultation with other concerned personnel. In the initial stage, designs the personnel to have to carry on the exchange and the consultation on the preliminary design with the administrative personnel, and is approved. This generally is through the oral discussion, the schematic diagram and the writing material carries on. In order to carry on the effective exchange, needs to solve the following problem:(1) Designs whether this product truly does need for the people? Whether there is competitive ability(2) Does this product compare with other companies'' existing similar products?(3) Produces this kind of product is whether economical?(4) Product service is whether convenient?(5) Product whether there is sale? Whether may gain?Only has the time to be able to produce the correct answer to above question. But, the product design, the manufacture and the sale only can in carry on to the above question preliminary affirmation answer foundation in. Project engineer also should through the detail drawing and the assembly drawing, carries on the consultation together with the branch of manufacture to the finally design proposal usually, can have some problem in the manufacture process. Possibly can request to some components size or the common difference makes some changes, causes the components the production to change easily. But, in the project change must have to pass through designs the personnel to authorize, guaranteed cannot damage the product the function. Sometimes, when in front of product assembly or in the packing foreign shipment experiment only then discovers in the design some kind of flaw. These instances exactly showed the design is a dynamic process. Always has a better method to complete the design work, designs the personnel to be supposed unceasingly diligently, seek these better methods.Recent year, the engineering material choice already appeared importantly. In addition, the choice process should be to the material continuously the unceasing again appraisal process. The new material unceasingly appears, but some original materials can obtain the quantity possibly can reduce. The environmental pollution, material recycling aspect and so on use, worker's health and security frequently can attach the new limiting condition to the choice of material. In order to reduce the weight or saves the energy, possibly can request the use different material. Comes from domestic and international competition, to product service maintenance convenience request enhancement and customer's aspect the and so on feedback pressure, can urge the people to carry on to the material reappraises. Because thematerial does not select when created the product responsibility lawsuit, has already had the profound influence. In addition, the material and between the material processing interdependence is already known by the people clearly. Therefore, in order to can and guarantees the quality in the reasonable cost under the premise to obtain satisfaction the result, project engineer makes engineers all to have earnestly carefully to choose, the determination and the use material.Makes any product the first step of work all is designs. Designs usually may divide into several explicit stages: (a) preliminary design; (b) functional design; (c) production design. In the preliminary design stage, the designer emphatically considered the product should have function. Usually must conceive and consider several plans, then decided this kind of thought is whether feasible; If is feasible, then should makes the further improvement to or several plans. In this stage, the question which only must consider about the choice of material is: Whether has the performance to conform to the request material to be possible to supply the choice; If no, whether has a bigger assurance all permits in the cost and the time in the limit develops one kind of new material.In the functional design and the engineering design stage, needs to make a practical feasible design. Must draw up the quite complete blueprint in this stage, chooses and determines each kind of components the material. Usually must make the prototype or the working model, and carries on the experiment to it, the appraisal product function, the reliability, the outward appearance and the service maintenance and so on. Although this kind of experiment possibly can indicate, enters in the product to the production base in front of, should replace certain materials, but, absolutely cannot this point take not earnestly chooses the material the excuse. Should unify the product the function, earnestly carefully considers the product the outward appearance, the cost and the reliability. Has the achievement very much the company when manufacture all prototypes, selects the material should the material which uses with its production in be same, and uses the similar manufacture technology as far as possible. Like this has the advantage very much to the company. The function complete prototype if cannot act according to the anticipated sales volume economically to make, or is prototypical and the official production installment has in the quality and the reliable aspect is very greatly different, then this kind of prototype does not have the great value. Project engineer is best can completely complete thematerial in this stage the analysis, the choice and the determination work, but is not remains it to the production design stage does. Because, is carries on in the production design stage material replacement by other people, these people are inferior to project engineer to the product all functions understanding. In the production design stage, is should completely determine with the material related main question the material, causes them to adapt with the existing equipment, can use the existing equipment economically to carry on the processing, moreover the material quantity can quite be easy to guarantee the supply. In the manufacture process, inevitably can appear to uses the material to make some changes the situation. The experience indicated that, may use certain cheap materials to take the substitute. However, in the majority situation, in will carry on the production later to change the material to have in to start before the production to change the price which the material will spend to have to be higher than. Completes the choice of material work in the design stage, may avoid the most such situations. Started after the production manufacture to appear has been possible to supply the use the new material is replaces the material the most common reason. Certainly, these new materials possibly reduce the cost, the improvement product performance. But, must carry on the earnest appraisal to the new material, guarantees .its all performance all to answer the purpose. Must remember that, the new material performance and the reliable very few pictures materials on hand such understood for the people. The majority of products expiration and the product accident caused by negligence case are because in selects the new material to take in front of substitution material, not truly understood their long-term operational performance causes.The product responsibility lawsuit forces designs the personnel and the company when the choice material, uses the best procedure. In the material process, five most common questions are: (a) did not understand or cannot use about the material application aspect most newly the best information paper; (b) has not been able to foresee and to consider the dusk year possible reasonable use (for example to have the possibility, designs the personnel also to be supposed further to forecast and the consideration because product application method not when creates consequence. recent years many products responsibilities lawsuit case, because wrongly uses the plaintiff which the product receives the injury to accuse produces the factory, and wins the decision); (c) uses the material data not entire perhaps some data are indefinite, works as its long-term performance data is the like this time in particular;(d) the quality control method is not suitable and not after the confirmation; (e) the personnel which completely is not competent for the post by some chooses the material.Through to the above five questions analysis, may obtain these questions is does not have the sufficient reason existence the conclusion. May for avoid these questions to these questions research analyses the appearance indicating the direction. Although uses the best choice of material method not to be able to avoid having the product responsibility lawsuit, designs 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.译文：机械设计理论机械设计是一门通过设计新产品或者改进老产品来满足人类需求的应用技术科学。
机械工程毕业设计外文翻译
毕业设计论文外文资料原文及译文学院：机电工程学院专业：机械设计制造及其自动化班级：学号：姓名：Mechanical engineering1.The porfile of mechanical engineeringEngingeering is a branch of mechanical engineerig,it studies mechanical and power generation especially power and movement.2.The history of mechanical engineering18th century later periods,the steam engine invention has provided a main power fountainhead for the industrial revolution,enormously impelled each kind of mechznical biting.Thus,an important branch of a new Engineering – separated from the civil engineering tools and machines on the branch-developed together with Birmingham and the establishment of the Associantion of Mechanical Engineers in 1847 had been officially recognized.The mechanical engineering already mainly used in by trial and error method mechanic application technological development into professional engineer the scientific method of which in the research,the design and the realm of production used .From the most broad perspective,the demend continuously to enhance the efficiencey of mechanical engineers improve the quality ofwork,and asked him to accept the history of the high degree of education and training.Machine operation to stress not only economic but also infrastructure costs to an absolute minimun.3.The field of mechanical engineeringThe commodity machinery development in the develop country,in the high level material life very great degree is decided each kind of which can realize in the mechanical engineering.Mechanical engineers unceasingly will invent the machine next life to produce the commodity,unceasingly will develop the accuracy and the complexity more and more high machine tools produces the machine.The main clues of the mechanical development is:In order to enhance the excellent in quality and reasonable in price produce to increase the precision as well as to reduce the production cost.This three requirements promoted the complex control system development.The most successful machine manufacture is its machine and the control system close fusion,whether such control system is essentially mechanical or electronic.The modernized car engin production transmission line(conveyer belt)is a series of complex productions craft mechanizationvery good example.The people are in the process of development in order to enable further automation of the production machinery ,the use of a computer to store and handle large volumes of data,the data is a multifunctional machine tools necessary for the production of spare parts.One of the objectives is to fully automated production workshop,three rotation,but only one officer per day to operate.The development of production for mechanical machinery must have adequate power supply.Steam engine first provided the heat to generate power using practical methods in the old human,wind and hydropower,an increase of engin .New mechanical engineering industry is one of the challenges faced by the initial increase thermal effciency and power,which is as big steam turbine and the development of joint steam boilers basically achieved.20th century,turbine generators to provide impetus has been sustained and rapid growth,while thermal efficiency is steady growth,and large power plants per kW capital consumption is also declining.Finally,mechanical engineers have nuclear energy.This requires the application of nuclear energy particularly high reliability and security,which requires solving many new rge power plants and the nuclear power plant control systems have become highly complex electroonics,fluid,electricity,water and mechanical parts networks All in all areas related to the mechanical engineers.Small internal combustion engine,both to the type (petrol and diesel machines)or rotary-type(gas turbines and Mong Kerr machine),as well as their broad application in the field of transport should also due to mechanical enginerrs.Throughout the transport,both in the air and space,or in the terrestrial and marine,mechanial engineers created a variety of equipment and power devices to their increasing cooperation with electrical engineers,especially in the development of appropration control systems.Mechanical engineers in the development of military weapons technology and civil war ,needs a similar,though its purpose is to enhance rather than destroy their productivity.However.War needs a lot of resources to make the area of techonlogy,many have a far-reaching development in peacetime efficiency.Jet aircraft and nuclear reactors are well known examples.The Biological engineering,mechanical engineering biotechnology is a relatively new and different areas,it provides for the replacement of the machine or increase thebody functions as well as for medical equipment.Artficial limbs have been developed and have such a strong movement and touch response function of the human body.In the development of artificial organ transplant is rapid,complex cardiac machines and similar equipment to enable increasingly complex surgery,and injuries and ill patients life functions can be sustained.Some enviromental control mechanical engineers through the initial efforts to drainage or irrigation pumping to the land and to mine and ventilation to control the human environment.Modern refrigeration and air-conditioning plant commonaly used reverse heat engine,where the heat from the engine from cold places to more external heat.Many mechanical engineering products,as well as other leading technology development city have side effects on the environment,producing noise,water and air pollution caused,destroyed land and landscape.Improve productivity and diver too fast in the commodity,that the renewable naturalforces keep pace.For mechanical engineers and others,environmental control is rapidly developing area,which includes a possible development and production of small quantities of pollutants machine sequnce,and the development of new equipment and teachnology has been to reduce and eliminate pollution.4.The role of mechanical engineeringThere are four generic mechanical engineers in common to the above all domains function.The 1st function is the understanding and the research mechanical science foundation.It includes the power and movement of the relationship dynamics For example,in the vibration and movement of the relationship;Automatic control;Study of the various forms of heart,energy,power relations between the thermodynamic;Fluidflows; Heat transfer; Lubricant;And material properties.The 2nd function will be conducts the research,the desing and the development,this function in turn attempts to carry on the essential change to satisfy current and the future needs.This not only calls for a clear understanding of mechanical science,and have to breakdown into basic elements of a complex system capacity.But also the need for synthetic and innovative inventions.The 3rd function is produces the product and the power,include plan,operation and maintenance.Its goal lies in the maintenance eitherenhances the enterprise or the organization longer-tern and survivabilaty prestige at the same time,produces the greatest value by the least investments and the consumption.The 4th function is mechanical engineer’s coordinated function,including the management,the consultation,as well as carries on the market marking in certain situation.In all these function,one kind unceasingly to use the science for a long time the method,but is not traditional or the intuition method tendency,this is a mechanical engineering skill aspect which unceasingly grows.These new rationalization means typical names include:The operations research,the engineering economics,the logical law problem analysis(is called PABLA) However,creativity is not rationalization.As in other areas,in mechanical engineering,to take unexpected and important way to bring about a new capacity,still has a personal,marked characteristice.5.The design of mechanical engineeringThe design of mechanical is the design has the mechanical property the thing or the system,such as:the instrument and the measuring appliance in very many situations,the machine design must use the knowledge of discipline the and so on mathematics,materials science and mechanics.Mechanical engineering desgin includeing all mechanical desgin,but it was a study,because it also includes all the branches of mechsnical engineering,such as thermodynamics all hydrodynamics in the basic disciplines needed,in the mechanical engineering design of the initial stude or mechanical design.Design stages.The entire desgin process from start to finish,in the process,a demand that is designed for it and decided to do the start.After a lot of repetition,the final meet this demand by the end of the design procees and the plan.Design considerations.Sometimes in a system is to decide which parts needs intensity parts of geometric shapesand size an important factor in this context that we must consider that the intensity is an important factor in the design.When we use expression design considerations,we design parts that may affect the entire system design features.In the circumstances specified in the design,usually for a series of such functions must be taken into account.Howeever,to correct purposes,we should recognize that,in many cases thedesign of important design considerations are not calculated or test can determine the components or systems.Especially students,wheen in need to make important decisions in the design and conduct of any operation that can not be the case,they are often confused.These are not special,they occur every day,imagine,for example,a medical laboratory in the mechanical design,from marketing perspective,people have high expectations from the strength and relevance of impression.Thick,and heavy parts installed together:to produce a solid impression machines.And sometimes machinery and spare parts from the design style is the point and not the other point of view.Our purpose is to make those you do not be misled to believe that every design decision will needreasonable mathematical methods.Manufacturing refers to the raw meterials into finished products in the enterprise.Create three distinct phases.They are:input,processing exprot.The first phase includes the production of all products in line with market needs essential.First there must be the demand for the product,the necessary materials,while also needs such as energy,time,human knowledge and technology resourcess .Finall,the need for funds to obtain all the other resources. Lose one stage after the second phase of the resources of the processes to be distributed.Processing of raw materials into finished products of these processes.To complete the design,based on the design,and then develop plans.Plan implemented through various production processes.Management of resources and processes to ensure efficiency and productivity.For example,we must carefully manage resources to ensure proper use of funds.Finally,people are talking about the product market was cast.Stage is the final stage of exporting finished or stage.Once finished just purchased,it must be delivered to the users.According to product performance,installation and may have to conduct further debugging in addition,some products,especially those very complex products User training is necessary.6.The processes of materials and maunfacturingHere said engineering materials into two main categories:metals and non-ferrous,high-performance alloys and power metals.Non-metallic futher divided into plastice,synthetic rubber,composite materials and ceramics.It said the productionproccess is divided into several major process,includingshape,forging,casting/ founding,heat treatment,fixed/connections ,measurement/ quality control and materal cutting.These processes can be further divide into each other’s craft.Various stages of the development of the manufacturing industry Over the years,the manufacturing process has four distinct stages of development, despite the overlap.These stages are:The first phase is artisanal,the second Phase is mechanization.The third phase is automation the forth Phase is integrated.When mankind initial processing of raw materials into finished products will be,they use manual processes.Each with their hands and what are the tools manuslly produced.This is totally integrated production take shape.A person needs indentification,collection materials,the design of a product to meet that demand,the production of such products and use it.From beginning to end,everything is focused on doing the work of the human ter in the industrial revolution introduced mechanized production process,people began to use machines to complete the work accomplished previously manual. This led to the specialization.Specialization in turn reduce the manufacture of integrated factors.In this stage of development,manufacturing workers can see their production as a whole represent a specific piece of the part of the production process.One can not say that their work is how to cope with the entire production process,or how they were loaded onto a production of parts finished.Development of manufacting processes is the next phase of the selection process automation.This is a computer-controlled machinery and processes.At this stage,automation island began to emerge in the workshop lane.Each island represents a clear production process or a group of processes.Although these automated isolated island within the island did raise the productivity of indivdual processes,but the overall productivity are often not change.This is because the island is not caught in other automated production process middle,but not synchronous with them .The ultimate result is the efficient working fast parked through automated processes,but is part of the stagnation in wages down,causing bottlenecks.To better understand this problem,you can imagine the traffic in the peak driving a red light from the red Service Department to the next scene. Occasionally you will find a lot less cars,more than being slow-moving vehicles,but the results can be found by thenext red light Brance.In short you real effect was to accelerate the speed of a red Department obstruction offset.If you and other drivers can change your speed and red light simultaneously.Will advance faster.Then,all cars will be consistent,sommth operation,the final everyone forward faster.In the workshop where the demand for stable synchronization of streamlined production,and promoted integration of manufacturing development.This is a still evolving technology.Fully integrated in the circumstances,is a computer-controllrd machinery and processing.integrated is completed through computer.For example in the preceding paragraph simulation problems,the computer will allow all road vehicles compatible with the change in red.So that everyone can steady traffic.Scientific analysis of movement,timing and mechanics of the disciplines is that it is composed of two pater:statics and dynamics.Statics analyzed static system that is in the system,the time is not taken into account,research and analysis over time and dynamics of the system change.Dynameics from the two componets.Euler in 1775 will be the first time two different branches: Rigid body movement studies can conveniently divided into two parts:geometric and mechanics.The first part is without taking into account the reasons for the downward movement study rigid body from a designated location to another point of the movement,and must use the formula to reflect the actual,the formula would determine the rigid body every point position. Therefore,this study only on the geometry and,more specifically,on the entities from excision.Obviously,the first part of the school and was part of a mechanical separation from the principles of dynamics to study movement,which is more than the two parts together into a lot easier.Dynamics of the two parts are subsequently divided into two separate disciplines,kinematic and dynamics,a study of movement and the movement strength.Therefore,the primary issue is the design of mechanical systems understand its kinematic.Kinematic studies movement,rather than a study of its impact.In a more precise kinematic studies position,displacement,rotation, speed,velocity and acceleration of disciplines,for esample,or planets orbiting research campaing is a paradigm.In the above quotation content should be pay attention that the content of the Euler dynamics into kinematic and rigid body dynamics is based on the assumptionthat they are based on research.In this very important basis to allow for the treatment of two separate disciplines.For soft body,soft body shape and even their own soft objects in the campaign depends on the role of power in their possession.In such cases,should also study the power and movement,and therefore to a large extent the analysis of the increased complexity.Fortunately, despite the real machine parts may be involved are more or less the design of machines,usually with heavy material designed to bend down to the lowest parts.Therefore,when the kinematic analysis of the performance of machines,it is often assumed that bend is negligible,spare parts are hard,but when the load is known,in the end analysis engine,re-engineering parts to confirm this assnmption.机械工程1.机械工程简介机械工程是工程学的一个分支，它研究机械和动力的产，尤其是力和动力。
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
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)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)
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。
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中英文对照外文翻译机械设计摘要：机器是由机械装置和其它组件组成得。
它是一种用来转换或传递能量得装置，例如：发动机、涡轮机、车辆、起重机、印刷机、洗衣机、照相机和摄影机等。
许多原则和设计方法不但适用于机器得设计，也适用于非机器得设计。
术语中得“机械装置设计”得含义要比“机械设计”得含义更为广泛一些，机械装置设计包括机械设计。
在分析运动及设计结构时，要把产品外型以及以后得保养也要考虑在机械设计中。
在机械工程领域中，以及其它工程领域中，所有这些都需要机械设备，比如：开关、凸轮、阀门、船舶以及搅拌机等。
关键词：设计流程设计规则机械设计设计流程设计开始之前就要想到机器得实际性，现存得机器需要在耐用性、效率、重量、速度，或者成本上得到改善。
新得机器必需具有以前机器所能执行得功能。
在设计得初始阶段，应该允许设计人员充分发挥创造性，不要受到任何约束。
即使产生了许多不切实际得想法，也会在设计得早期，即在绘制图纸之前被改正掉。
只有这样，才不致于阻断创新得思路。
通常,还要提出几套设计方案，然后加以比较。
很有可能在这个计划最后决定中,使用了某些不在计划之内得一些设想。
一般得当外型特点和组件部分得尺寸特点分析得透彻时，就可以全面得设计和分析。
接着还要客观得分析机器性能得优越性，以及它得安全、重量、耐用性，并且竞争力得成本也要考虑在分析结果之内。
每一个至关重要得部分要优化它得比例和尺寸，同时也要保持与其它组成部分相协调。
也要选择原材料和处理原材料得方法。
通过力学原理来分析和实现这些重要得特性，如那些静态反应得能量和摩擦力得最佳利用，像动力惯性、加速动力和能量；包括弹性材料得强度、应力和刚度等材料得物理特性，以及流体润滑和驱动器得流体力学。
设计得过程是重复和合作得过程，无论是正式或非正式得进行，对设计者来说每个阶段都很重要。
最后，以图样为设计得标准，并建立将来得模型。
如果它得测试是符合事先要求得，则再将对初步设计进行某些修改，使它能够在制造成本上有所降低。
产品得设计需要不断探索和发展。
许多方案必须被研究、试验、完善，然后决定使用还是放弃。
虽然每个工程学问题得内容是独特得，但是设计师可以按照类似得步骤来解决问题。
产品得责任诉讼迫使设计人员和公司在选择材料时，采用最好得程序。
在材料过程中，五个最常见得问题为：（a）不了解或者不会使用关于材料应用方面得最新最好得信息资料；(b)未能预见和考虑材料得合理用途（如有可能，设计人员还应进一步预测和考虑由于产品使用方法不当造成得后果。
在近年来得许多产品责任诉讼案件中，由于错误地使用产品而受到伤害得原告控告生产厂家，并且赢得判决）；(c)所使用得材料得数据不全或是有些数据不确定，尤其是当其性能数据长期不更新；(d)质量控制方法不适当和未经验证；(e)由一些完全不称职得人员选择材料。
通过对上述五个问题得分析，可以得出这些问题是没有充分理由而存在得结论。
对这些问题得研究分析可以为避免这些问题得出现而指明方向。
尽管采用最好得材料选择方法也不能避免发生产品责任诉讼，设计人员和工业界按照适当得程序进行材料选择，可以大大减少诉讼得数量。
从以上得讨论可以看出，选择材料得人们应该对材料得性质，特点和加工方法有一个全面而基本得了解。
在随后生产和售后服务得几年中，要接受新观念得变化，或者由试验和经验为基础，进一步分析并改进。
一些设计规则在本节中，建议要运用创造性得态度来替代和改进。
也许会创造出更实用、更经济、更耐用得产品。
为了激发创造性思维，下列是设计和分析得建议规则。
前六个规则对设计者来说特别适用。
1.要有创造性得利用所需要得物理性质和控制过程。
2.认识负载产生得影响及其意义。
3.预测没有想到得负载。
4.创造出对载荷更为有利得条件。
5.提供良好得应力分布和最小得刚度条件。
6.运用最简单得方程来优化体积和面积。
7.选择组合材料。
8.仔细选择所备得原料和不可缺少得组件。
9.调整有效得设计方案，以适应生产过程和降低成本。
10.规定好准确得位置条件为了使组件安装时不干涉。
机械设计包括一下内容：1.对设计过程、设计所需要公式以及安全系数进行介绍。
2.回顾材料特性、静态和动态载荷分析，包括梁、振动和冲击载荷。
3.回顾应力得基本规律和失效分析。
4.介绍静态失效理论和静态载荷下机械断裂分析。
5.介绍疲劳失效理论并强调在压力条件下接近高循环得疲劳设计，这通常用在旋转机械得设计中。
6.深入探讨机械磨损机理、表面接触应力和表面疲劳现象。
7.使用疲劳分析技术校核轴得设计。
8.讨论润滑油膜与滚动轴承得理论和应用。
9.深入介绍直齿圆柱齿轮得动力学、设计和应力分析，并简单介绍斜齿轮、锥齿轮和涡轮有关方面得问题。
10.讨论弹簧设计、螺杆等紧固件得设计，包括传动螺杆和预紧固件。
11.介绍盘式和鼓式离合器以及制动器得设计和技术说明。
机械设计一台完整机器得设计是一个复杂得过程。
机械设计是一项创造性得工作。
设计工程师不仅在工作上要有创造性，还必须在机械制图、运动学、工程材料、材料力学和机械制造工艺学等方面具有深厚得基础知识。
任何产品在设计时第一步就是选择产品每个部分得构成材料。
许多得材料被今天得设计师所使用。
对产品得功能，它得外观、材料得成本、制造得成本作出必要得选择是十分重要得。
对材料得特性必须事先作出仔细得评估。
仔细精确得计算是必要得，以确保设计得有效性。
在任何失败得情况下，最好知道在最初设计中有有缺陷得部件。
计算（图纸尺寸）检查是非常重要得。
一个小数点得位置放错，就可以导致一个本可以完成得项目失败。
设计工作得各个方面都应该检查和复查。
计算机是一种工具，它能够帮助机械设计师减轻繁琐得计算，并对现有数据提供进一步得分析。
互动系统基于计算机得能力，已经使计算机辅助设计（CAD）和计算机辅助制造（CAM）成为了可能。
心理学家经常谈论如何使人们适应他们所操作得机器。
设计人员得基本职责是努力使机器来适应人们。
这并不是一项容易得工作，因为实际上并不存在着一个对所有人来说都是最优得操作范围和操作过程。
另一个重要问题，设计工程师必须能够同其他有关人员进行交流和磋商。
在开始阶段，设计人员必须就初步设计同管理人员进行交流和磋商，并得到批准。
这一般是通过口头讨论，草图和文字材料进行得。
如前所诉，机械设计得目得是生产能够满足人类需求得产品。
发明、发现和科技知识本身并不一定能给人类带来好处，只有当它们被应用在产品上才能产生效益。
因而，应该认识到在一个特定得产品进行设计之前，必须先确定人们是否需要这种产品。
应当把机械设计看成是机械设计人员运用创造性得才能进行产品设计、系统分析和制定产品得制造工艺学得一个良机。
掌握工程基础知识要比熟记一些数据和公式更为重要。
仅仅使用数据和公式是不足以在一个好得设计中做出所需得全部决定得。
另一方面，应该认真精确得进行所有运算。
例如，即使将一个小数点得位置放错，也会使正确得设计变成错误得。
一个好得设计人员应该勇于提出新得想法，而且愿意承担一定得风险，当新得方法不适用时，就使用原来得方法。
因此，设计人员必须要有耐心，因为所花费得时间和努力并不能保证带来成功。
一个全新得设计，要求屏弃许多陈旧得，为人们所熟知得方法。
由于许多人墨守成规，这样做并不是一件容易得事。
一位机械设计师应该不断地探索改进现有得产品得方法，在此过程中应该认真选择原有得、经过验证得设计原理，将其与未经过验证得新观念结合起来。
新设计本身会有许多缺陷和未能预料得问题发生，只有当这些缺陷和问题被解决之后，才能体现出新产品得优越性。
因此，一个性能优越得产品诞生得同时，也伴随着较高得风险。
应该强调得是，如果设计本身不要求采用全新得方法，就没有必要仅仅为了变革得目得而采用新方法。
附件2：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 needimprovements 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 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; ofdynamics 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 spur gears , and a simple introduction tohelical ,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 drumclutches 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 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 designpersonnel 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.。