机械设计外文文献翻译、中英文翻译、外文翻译.docx

1、附录A英文原文MechanicalDesignAmachineisacombinationofmechanismsandothercomponentswhichtransforms,transmits.Examplesareengines,turbines,vehicles,hoists,printingpresses,washingmachines,andmoviecameras.Manyoftheprinciplesandmethodsofdesignthatapplytomachinesalsoapplytomanufacturedarticlesthatarenottruemachin

2、es.Theterm"mechanicaldesign,1isusedinabroadersensethannmachinedesign"toincludetheirdesign,themotionandstructuralaspectsandtheprovisionsforretentionandenclosureareconsiderationsinmechanicaldesign.Applicationsoccurinthefieldofmechanicalengineering,andinotherengineeringfieldsaswell,allofwhich

3、requiremechanicaldevices,suchasswitches,cams,valves,vessels,andmixers.TheDesignProcessDesigningstartswithaneedreal.Existingapparatusmayneedimprovementsindurability,efficiency,weight,speed,orcost.Newapparatusmaybeneededtoperformafunctionpreviouslydonebymen,suchascomputation,assembly,orservicing.Witht

4、heobjectivewhollyorpartlylnthedesignpreliminarystage,shouldallowtodesignthepersonnelfullytodisplaythecreativity,noteachkindofrestraint.Evenifhashadmanyimpracticalideas,alsocaninthedesignearlytime,namelyinfrontoftheplanblueprintiscorrected.Onlythen,onlythendoesnotsendtostopsuptheinnovationthementalit

5、y.Usually,mustproposeseveralsetsofdesignproposals,thenperformthecomparison.Hasthepossibilityverymuchintheplanwhichfinallydesignated,hasusedcertainnotinplansomeideaswhichaccepts.Whenthegeneralshapeandafewdimensionsoftheseveralcomponentsbecomeapparent,analysiscanbegininearnest.Theanalysiswillhaveasits

6、objectivesatisfactoryorsuperiorperformance,plussafetyanddurabilitywithminimumweight,andacompetitivecost.Optimumproportionsanddimensionswillbesoughtfbreachcriticallyloadedsection,togetherwithabalancebetweenthestrengthsoftheseveralcomponents.Materialsandtheirtreatmentwillbechosen.Theseimportantobjecti

7、vescanbeattainedonlybyanalysisbasedupontheprinciplesofmechanics,suchasthoseofstaticforreactionforcesandfortheoptimumutilizationoffriction;ofdynamicsforinertia,acceleration,andenergy;ofelasticityandstrengthofmaterialsforstressanddeflection;ofphysicalbehaviorofmaterials;andoffluidmechanicsforlubricati

8、onandhydrodynamicdrives.Theanalysesmaybemadebythesameengineerwhoconceivedthearrangementofmechanisms,or,inalargecompany,theymaybemadebyaseparateanalysisdivisionorresearchgroup.Designisareiterativeandcooperativeprocess,whetherdoneformallyorinformally,andtheanalystcancontributetophasesotherthanhisown.P

9、roductdesignrequiresmuchresearchanddevelopment.ManyConceptsofanideamustbestudied,tried,andtheneitherusedordiscarded.Althoughthecontentofeachengineeringproblemisunique,thedesignersfollowthesimilarprocesstosolvetheproblems.Productliabilitysuitsdesignersandforcedinmaterialselection,usingthebestprogramI

10、ntheprocessofmaterial,themostcommonproblemsforfive(a)don*tunderstandornotuseaboutthelatestapplicationmaterialstothebestinformation,(b)foiledtoforeseeandconsiderthereasonableusematerialmay(suchaspossible,designersshouldfurtherforecastandconsiderduetoimproperuseproducts.Inrecentyears,manyproductsliabi

11、lityinlitigation,theuseofproductsandhurttheplaintiffaccusedmanuiacturer,andwonthedecision),(c)ofthematerialsusedallorsomeofthedata,data,especiallywhentheuncertaintylong-termperformancedataisso,(d)qualitycontrolmethodisnotsuitableandunproven,(e)bysomecompletelyincompetentpersonschoosematerials.Throug

12、htotheabovefivequestionsanalysis,mayobtainthesequestionsisdoesnothavethesufficientreasonexistencetheconclusion.Mayforavoidthesequestionstothesequestionsresearchanalysestheappearanceindicatingthedirection.Althoughusesthebestchoiceofmaterialmethodnottobeabletoavoidhavingtheproductresponsibilitylawsuit

13、,designsthepersonnelandtheindustrycarriesonthechoiceofmaterialaccordingtothesuitableprocedure,maygreatlyreducethelawsuitthequantity.Mayseefromtheabovediscussion,thechoicematerialpeopleshouldtothematerialnature,thecharacteristicandtheprocessingmethodhaveconprehensiveandthebasicunderstanding.Finally,a

14、designbaseduponfunction,andaprototypemaybebuilt.Ifitstestsaresatisfactory,theinitialdesignwillundergocertainmodificationsthatenableittobemanufocturedinquantityatalowercost.Duringsubsequentyearsofmanufoctureandservice,thedesignislikelytoundergochangesasnewideasareconceivedorasfurtheranalysesbasedupon

15、testsandexperienceindicatealterations.Salesappeal.SomeRulesforDesignInthissectionitissuggestedthat,appliedwithacreativeattitude,analysescanleadtoimportantimprovementsandtotheconceptionandperfectionofalternate,perhapsmorefonctional,economical,anddurableproducts.Tostimulatecreativethought,thefollowing

16、rulesaresuggestedforthedesignerandanalyst.Thefirstsixrulesareparticularlyapplicablefortheanalyst.1. Acreativeuseofneedofphysicalpropertiesandcontrolprocess.2. Recognizefunctionalloadsandtheirsignificance.3. Anticipateunintentionalloads.4. Devisemoreftivorableloadingconditions.5. Provideforfevorables

17、tressdistributionandstiffnesswithminimumweight.6. Usebasicequationstoproportionandoptimizedimensions.7. Choosematerialsforacombinationofproperties.8. Selectcarefully,stockandintegralcomponents.9. Modifyafunctionaldesigntofitthemanufecturingprocessandreducecost.10. Provideforaccuratelocationandnonint

18、erferenceofpartsinassembly.Machinerydesigncoversthefollowingcontents.1. Providesanintroductiontothedesignprocess,problemformulation,safetyiactors.2. Reviewsthematerialpropertiesandstaticanddynamicloadinganalysis,Includingbeam,vibrationandimpactloading.3. Reviewsthefundamentalsofstressanddefectionana

19、lysis.4. Introducesfatigue-failuretheorywiththeemphasisonstress-lifeapproachestohigh-cyclefatiguedesign,whichiscommonlyusedinthedesi印ofrotationmachinery.5. Discussesthoroughlythephenomenaofwearmechanisms,surfacecontactstresses,andsurfacefetigue.6. Investigatesshaftdesignusingthefotigue-analysistechn

20、iques.7. Discussesfluid-filmandrolling-elementbearingtheoryandapplicationGivesathoroughintroductiontothekinematics,designandstressanalysisofspurgears,andasimpleintroductiontohelical,bevel,andwormgearing.8. Discussesspringdesignincludingcompression,extensionandtorsionsprings.9. Dealswithscrewsandfast

21、enersincludingpowerscrewandpreloadfesteners.10. Introducesthedesignandspecificationofdiskanddrumclutchesandbrakes.MachineDesignTheconpletedesignofamachineisacomplexprocess.Themachinedesignisacreativework.Projectengineernotonlymusthavethecreativityinthework,butalsomustinaspectandsoonmechanicaldrawing

22、,kinematics,engineerigmaterial,materialsmechanicsandmachinemanufecturetechnologyhasthedeepelementaryknowledge.Oneofthefirststepsinthedesignofanyproductistoselectthematerialfromwhicheachpartistobemade.Numerousmaterialsareavailabletotoday'sdesigners.Thefunctionoftheproduct,itsappearance,thecostoft

23、hematerial,andthecostoffabricationareimportantinmakingaselection.Acarefulevaluationofthepropertiesofa.materialmustbemadepriortoanycalculations.Carefulcalculationsarenecessarytoensurethevalidityofadesign.Incaseofanypartfeilures,itisdesirabletoknowwhatwasdoneinoriginallydesigningthedefectivecomponents

24、.Thecheckingofcalculations(anddrawingdimensions)isofutmostimportance.Themisplacementofonedecimalpointcanruinanotherwiseacceptableproject.Allaspectsofdesignworkshouldbecheckedandrechecked.Thecomputerisatoolhelpfultomechanicaldesignerstolightentediouscalculations,andprovideextendedanalysisofavailabled

25、ata.Interactivesystems,basedoncomputercapabilities,havemadepossibletheconceptsofcomputeraideddesign(CAD)andcomputer-aidedmanufocturing(CAM).Howdoesthepsychologistfrequentlydiscusscausesthemachinewhichthepeopleadaptsthemtooperate.Designspersonnelsbasicresponsibilityisdiligentlycausesthemachinetoadapt

26、thepeople.Thiscertainlyisnotaneasywork,becausecertainlydoesnothavetoallpeopletosayinfactallisthemostsuperioroperatingareaandtheoperatingprocess.Anotherimportantquestion,projectengineermustbeabletocarryontheexchangeandtheconsultationwithotherconcernedpersonnel.Intheinitialstage,designsthepersonneltoh

27、avetocarryontheexchangeandtheconsultationonthepreliminarydesignwiththeadministrativepersonnel,andisapproved.Thisgenerallyisthroughtheoraldiscussion,theschematicdiagramandthewritingmaterialcarrieson.Iffrontsues,themachinedesigngoalistheproductioncanmeetthehumanneedtheproduct.Theinvention,thediscovery

28、andtechnicalknowledgeitselfcertainlynotnecessarilycanbringtheadvantagetothehumanity,onlyhaswhentheyareappliedcanproduceontheproductthebenefit.Thus,shouldrealizetocarriesonbeforethedesigninaspecificproduct,mustfirstdeterminewhetherthepeopledoneedthiskindofproductMustregardasthemachinedesignisthemachi

29、nedesignpersonnelcarriesonusingcreativeabilitytheproductdesign,thesystemanalysisandaformulationproductmanufacturetechnologygoodopportunity.Graspstheprojectelementaryknowledgetohavetomemorizesomedataandtheformulaismoreimportantthan.Themerelyservicedataandtheformulaisinsufficienttothecompletelydecisio

30、nwhichmakesinagooddesignneeds.Ontheotherhand,shouldbeearnestpreciselycarriesonalloperations.Forexample,evenifplaceswrongadecimalpointposition,alsocancausethecorrectdesigntoturnwrongly.Agooddesignpersonnelshoulddaretoproposethenewidea,moreoveriswillingtoundertakethecertainrisk,whenthenewmethodisnotsu

31、itable,useoriginalmethod.Therefore,designsthepersonneltohavetohavetohavethepatience,becausespendsthetimeandtheendeavorcertainlycannotguaranteebringssuccessfully.Abrand-newdesign,therequestscreenabandonsobsoletelymany,knowsverywellthemethodforthepeople.Becausemanypersonofconservativeness,doesthiscert

32、ainlyisnotaneasymatter.Amechanicaldesignershouldunceasinglyexploretheimprovementexistingproductthemethod,shouldearnestlychooseoriginally,theprocessconfirmationprincipleofdesigninthisprocess,withhasnotunifieditaftertheconfirmationnewidea.附录B中文翻译机械设计机器是由机械装置和其它组件组成的。它是一种用来转换或传递能量的装置，例如：发动机、涡轮机、车辆、起重机、

33、印刷机、洗衣机、照相机和摄影机等。许多原则和设计方法不但适用于机器的设计，也适用于非机器的设计。术语中的“机械装置设计”的含义要比“机械设计”的含义更为广泛一些，机械装置设计包括机械设计。在分析运动及设计结构时，要把产品外型以及以后的保养也要考虑在机械设计中。在机械工程领域中，以及其它工程领域中，所有这些都需要机械设备，比如：开关、凸轮、阀门、船舶以及搅拌机等。设计流程设计开始之前就要想到机器的实际性，现存的机器需要在耐用性、效率、重量、速度，或者成本上得到改善。新的机器必需具有以前机器所能执行的功能。在设计的初始阶段，应该允许设计人员充分发挥创造性，不要受到任何约束。即使产生了许多不切实际的

34、想法，也会在设计的早期，即在绘制图纸之前被改正掉。只有这样，才不致于阻断创新的思路。通常，还要提出几套设计方案，然后加以比较。很有可能在这个计划最后决定中，使用了某些不在计划之内的一些设想。一般的当外型特点和组件部分的尺寸特点分析得透彻时，就可以全面的设计和分析。接着还要客观的分析机器性能的优越性，以及它的安全、重量、耐用性，并且竞争力的成本也要考虑在分析结果之内。每一个至关重要的部分要优化它的比例和尺寸,同时也要保持与其它组成部分相协调。也要选择原材料和处理原材料的方法。通过力学原理来分析和实现这些重要的特性，如那些静态反应的能量和摩擦力的最佳利用，像动力惯性、加速动力和能量；包括弹性材料的

35、强度、应力和刚度等材料的物理特性，以及流体润滑和驱动器的流体力学。设计的过程是重复和合作的过程，无论是正式或非正式的进行，对设计者来说每个阶段都很重要。最后，以图样为设计的标准，并建立将来的模型。如果它的测试是符合事先要求的，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。产品的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的内容是独特的，但是设计师可以按照类似的步骤来解决问题。产品的责任诉讼迫使设计人员和公司在选择材料时，采用最好的程序。在材料过程中，五个最常见的问题为：(a) 不了解或者不会使用关于材料应用方面的最新最好的信息资

36、料；(b) 未能预见和考虑材料的合理用途(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的后果。在近年来的许多产品责任诉讼案件中，由于错误地使用产品而受到伤害的原告控告生产厂家，并且赢得判决)；(c) 所使用的材料的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) 由一些完全不称职的人员选择材料。通过对上述五个问题的分析，可以得出这些问题是没有充分理由而存在的结论。对这些问题的研究分析可以为避免这些问题的出现而指明方向。尽管采用最好的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的程序进行材料选择，可以大大

37、减少诉讼的数量。从以上的讨论可以看出，选择材料的人们应该对材料的性质，特点和加工方法有一个全面而基本的了解。在随后生产和售后服务的几年中，要接受新观念的变化，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1.在本节中，建议要运用创造性的态度来替代和改进。也许会创造出更实用、更经济、更耐用的产品。2.为了激发创造性思维，下列是设计和分析的建议规则。前六个规则对设计者来说特别适用。3.要有创造性的利用所需要的物理性质和控制过程。4.认识负载产生的影响及其意义。5.预测没有想到的负载。6.创造出对载荷更为有利的条件。7.提供良好的应力分布和最小的刚度条件。8.运用最简单的方程来优化体积和面积

38、。9.选择组合材料。10. 仔细选择所备的原料和不可缺少的组件。11. 调整有效的设计方案，以适应生产过程和降低成本。12. 规定好准确的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. 回顾应力的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的疲劳设计，这通常用在旋转机械的设计中。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的设计。8. 讨论润滑油膜与滚动轴承的理论和应用。9. 深入介绍直齿圆柱齿轮