《机械工程英语》课件Chapter 3

Chapter3MechanicalDesigningWarming-upListeningSpeakingReadingWriting&TranslationObjectives

Afterstudyingthischapter,youareableto:

·mastersomeexpressionsaboutproductdesign.

·communicatewithaclientaboutthedesignrequirementsofaproduct.

·discussthedesignofaproductwithcolleaguesandmakeapresentationofthedesigntotheclient.

·describethefunctionsandapplicationofCADandCAM.

·introducetheproductionprocessandstatustoclients.

Warming-up

Task1DoyouknowthefollowingEnglishwords?Pleasematchthewordswiththefollowingpictures.robotconveyorstampingmachinechiselweldingsteelsheetsteeringwheelrollengineprotectiveclothTask2Listentothenewsreportandanswerthequestions.Oneoftheworld’slargestindustrialrobotmakersbeginsoperationsatitsnewShanghaifactoryonTuesday.GermanrobotmanufacturerKukaisaimingformulti-millioneuroordersforitshigh-techmachineryfromChina’sautomotiveindustry.Germany’stabletennischampiontakesonthefastestrobotinapingpongbattle.That’sthetypeofmachinerythatwillbeproducedinKuka’snewplantinShanghai,thefirstinthecountryfortheAugsburg-basedrobotmaker.Chinaisprojectedtobecomethebiggestmarketforindustrialroboticsby2019.RightnowChineserobotproductsonlymakeupaboutatenthoftheChinesemarket.Questions：1.Doyouthinkitisimportanttopondermoreabouthomo-roborelations?2.Whatshouldwedowiththearrivalofincreasinglyhumanoidautomatonsinworkplaces?

Listening

Task1Listencarefullyandfillintheblankswiththewordyouhearonthetape.Machinedesignistheapplicationof1and2todevisenewor3productsforthe4ofsatisfyinghuman5.Itisavastfieldof6technologythatnotonly7itselfwiththeoriginalconceptionofaproductintermsofits8,9,and10detailsbutalsoconsidersthevariousfactorsinvolvedinthemanufacture,marketingandtheuseoftheproduct.Task2Listencarefullyandfillintheblankswiththewordyouhearonthetape.Alarge1CAMsystem2a3structureoftwoorthree4ofcomputersthatareusedtocontroland5individualprocesstasks.Asmallcomputeris6forthemanagementofa7processwithalargercomputermonitoringand8instructionstoagroupofsmallcomputers.A9computerthenfeedsthesystemwith10information.AlargescaleCAMsystem11threemajorareasrelatedtothemanufacturingprocess:productionmanagementandcontrol;engineering12and13;andfinanceandmarketing.Eachiscomprisedofsubtasksthatarecontrolledeitherdirectlyformalargecomputer,orbyasmallcomputer,asinthecaseofinspection14control.Regardlessofthecontrolmethod,theimportantstrengthofCAMisthata15flowofinformationoccurs.Task3VisitingMetalProcessingWorkshop.Choosethebestansweraccordingtothedialogue.GuJieisshowingJohnTurneraroundtheworkshop.GuJieintroducestoJohnTurnertheturningandmillingmachinesintheworkshop.JohnTurnerasksabouttheuseofturningmachinesandthepositionsofmainspindleandtailstock.Mr.GuexplainstohimwhatareprocessedhereandgivesJohnaclearideaofhowcompactaturningmachinecanbe.1.Wheredoestheconversationtakeplace?()A.OfficeB.WorkshopC.Warehouse2.HowmanytypesofmachinetoolsareusedinMr.Chen’sworkshop?()A.TwoB.FourC.Three3.Whatmachinetoolsaremainlyusedformachiningshaftcomponentsandcasetypedparts?()A.MillingmachinesB.TurningmachinesC.BothAandB4.Different____willleadtodifferentmachiningeffects.A.shafts B.machines C.cuttingtools5.JohnTurnerthinksthatturningmachinesare________.A.useful B.marvelous C.commonTask4Youhave2colleagues,theyaretalkingaboutCAMnow.Listentotheconversationandanswerthefollowingquestions.1.WhatisCAD?2.HowdoCADandCAMsystemsworktogetherinmanufacture?3.WhatisthemainfunctionofCAM?4.WhatisthemanufacturingprocesscontrolledbyinaCAMsystem?5.WhataretheadvantagesofCAMmentionedinthetalk?Pleasenotedownoneofthem.

Speaking

Task1TrytoexplainhowthissimplemechanismoperatesusingwhateverEnglishyouknow.Workinpairsdescribeyourexplanationtoyourpartner.Note:Four-barlinkage(四平杆),crank-rockerlinkages(曲柄摇杆机构)L1:acrankL2:acouplerorafollowerL3:arockerL4:fixedlinkTask2Workwithyourpartnertomatcheachsymbolwithitsindication.Thendrawanyofthesymbolsonapieceofpaperandtaketurnstotellyourpartneritsmeaningandwhereitcanbeseen.1.Thissymbolindicatesthatlethalaccidentsorseriousinjuriesmayoccuriftheoperatingandworkinginstructionsarenotfollowedproperly.2.Thissymboldrawsyourattentiontosomethingparticular.3.Thissymbolwarnsagainstdangerousvoltage!Immediatedeathmightbetheconsequence.4.Thissymbolinformstheuserthatthesystemoritscomponentsmaybedamagediftheworkingandoperatinginstructionsarenotfollowed.5.Thissymbolindicatescompulsoryactionsthatmustbeperformedbytheoperator.6.Thissymbolindicatesprohibitiveactionsthatmustnotbeperformedbytheoperator.Task3Workinpairs.AisnowpresentingtheprototypeofelectricscootertoB.Makeaconversationwithyourpartneraccordingtotheinformationgivenbelow.A：·Askabouttheappearance.·Wanttoknowaboutthespeed.·Enquireaboutweight.·Wonderwhetherthereisanyotherinformation.·Showyoursatisfaction.B：·Brightorangecolor;34incheslong,7incheswide,and35inchesfromdecktohandlebars;tough,aluminumbody.·15milesperhouratmost.·Lightenoughtobecarriedintotheoffice;19.5poundsinweight;easytofoldup.·Lowdeckheight;easykickscooting;completelyredesignedmotorcontroller;improvedperformance.

Reading

TextAPlasticMoldingPlasticscanbemoldedintovariousformsandhardenedforcommercialuse.Plasticmoldingproductscanbeseeneverywhere.Examplesarejars,protectivecaps,plastictubes,toys,bottles,cases,accessories,kitchenutensilsandalotmore.Thekeyboardandthemousethatyouusearemadethroughplasticmoldingandeventheplasticpartsofthechairthatyouaresittingonarecreatedthisway.Thebasicideainplasticmoldingisinsertingmoltenliquidplasticintoareadyshapedmold,forexample,themoldofabottle.Itwillbethenallowedtocool,thenthemoldwillberemovedtorevealtheplasticbottle.Ifyouareplanningtogointoplasticmoldingbusiness,youshouldfirstknowthedifferentprocesses.Herearebasicdefinitionsofvariousmethodsofplasticmolding.InjectionMoldingInInjectionMolding,meltedplasticisforcedintoamoldcavity.Oncecooled,themoldcanberemoved.Thisplasticmoldingprocessiscommonlyusedinmass-productionofaproduct.Injectionmoldingmachinesweremadeinthe1930’s.Thesecanbeusedtomassproducetoys,kitchenutensils,bottlecaps,andcellphonestands.BlowMoldingBlowmoldingislikeinjectionmoldingexceptthathotliquidplasticpoursoutofabarrelverticallyinamoltentube.Themoldclosesonitandforcesitoutwardtoconformtotheinsideshapeofthemold.Whenitiscooled,thehollowpartisformed.Examplesofblowmoldingproductsarebottles,tubesandcontainers.CompressionMoldingInthistypeofplasticmolding,hardplasticispressedbetweentwoheatedmoldhalves.Compressionmoldingusuallyusesverticalpressesinsteadofthehorizontalpressesusedforinjectionandblowmolding.Thepartsformedarethenair-cooled.RotationalMoldingHollowmoldspackedwithpowderedplasticaresecuredtopipe-likespokesthatextendfromacentralhub.Thehubswingsthewholemoldtoaclosedfurnaceroomcausingthepowdertomeltandsticktotheinsidesofthetools.Asthemoldsturnslowly,thetoolsmoveintoacoolingroom.Here,sprayedwatercausestheplastictohardenintoahollowpart.NewWordsandExpressionsbarrel[bærəl]n.圆筒，adj.筒状物体cavity[kævətɪ]n.腔，凹处container[kənteɪnə(r)]n.容器furnace[fɜːnɪs]n.熔炉harden[hɑːdn]v.变硬，凝固hollow[hɒləʊ]adj.中空的；n.坑，洞hub[hʌb]n.轮轴，轮毂jar[dʒɑː(r)]n.瓶，罐mass[mæs]n.大量，大块；vt.(使)集中，聚集molten[məʊltən]adj.融化的，熔融状的outward[aʊtwəd]adv.向外，在外；adj.向外的，外面的powder[paʊdə(r)]n.粉末；v.涂粉reveal[rɪviːl]v.揭露，显露出，展现出rotational[rəʊ'teɪʃənl]adj.转动的，旋转的spoke[spəʊk]n.轮辐，(车轮的)辐条spray[spreɪ]v.喷洒，喷射swing[swɪŋ]v.使旋转，使摆动tube[tjuːb]n.管，管状物utensil[juːtensl]n.器皿，用具vertically['vɜːtɪklɪ]adj.垂直的conformto和……一致InjectionMolding注塑成型Blowmolding吹塑成型Compressionmolding压缩成型Rotationalmolding滚塑成型Notes：不同塑模成型工艺区别示意图InjectionMolding注塑成型BlowMolding吹塑成型CompressionMolding压缩成型RotationalMolding滚塑成型Task1Answerthefollowingquestionsaccordingtothetext.1．Inadditiontotheitemsmentionedinthetext,canyoumakesomeotherexamplesofplasticmoldingproductsinyourdailylife?2．Whatdidtheinventionofinjectionmoldingmachinesmeantothemanufacturer?3．Whatisthedifferencebetweeninjectionmoldingandblowmolding?4．Whatisthedifferenceintermsofrawmaterialamongthefourtypesofplasticmolding?Task2MatchtheEnglishexpressionswiththeirChinesemeanings.1.plasticmolding A.批量生产2.verticalpresses B.管状胚料3.moldcavity C.管状轮辐4.injectionmoldingD.模具型腔5.air-cooled E.注塑成型6.protectivecaps F.空心件7.hollowpart G.塑料成型8.massproductionH.安全帽9.moltentube I.立式压力机10.pipe-likespokes J.冷却Task3Pleasewriteoutthewordsinaccordingtotheirdefinitions.Thefirstlettersarealreadygiven.1.c______abox,bottle,etc.inwhichsomethingcanbestoredortransported.2.b______alargeroundcontainer,usuallymadeofwoodormetal,withflatendsand,usually,curvedsides.3.o______goingawayfromaparticularplace,especiallyonethatyouaregoingtoreturnto.4.r______theactionofanobjectmovinginacirclearoundacentralfixedpoint.5.s______tocoversb/sthwithverysmalldropsofaliquidthatareforcedoutofacontainerorsentthroughtheair.6.i______anactofforcingliquidintosomething.7.c______pressorsqueezesthsothatittakesuplessspace.8.v______somethingstandsorpointsstraightup.Task4TranslatethefollowingpassageintoChinese.Hollowmoldspackedwithpowderedplasticaresecuredtopipe-likespokesthatextendfromacentralhub.Thehubswingsthewholemoldtoaclosedfurnaceroomcausingthepowdertomeltandsticktotheinsidesofthetools.Asthemoldsturnslowly,thetoolsmoveintoacoolingroom.Here,sprayedwatercausestheplastictohardenintoahollowpart.TextBMoldDesignandManufacturingCADandCAMarewidelyappliedinmolddesignandmoldmaking.Computer-AidedManufacturing(CAM)canbedefinedastheuseofcomputersystemstoplan,manage,andcontroltheoperationsofamanufacturingplantthrougheitherdirectorindirectcomputerinterfacewiththeplant’sproductionresources.CAMfunctionscenteraroundfourmainareas:numericalcontrol,processplanning,robotics,andfactorymanagement.NumericalControl(NC)Numericalcontrolusescodedinformationtocontrolmachinetoolmovements.InmodernCNCsystems,end-to-endcomponentdesignishighlyautomatedusingCAMprograms.Theprogramsproduceacomputerfilethatisinterpretedtoextractthecommandsneededtooperateaparticularmachine,andthenloadedintotheCNCmachinesforproduction.ProcessPlanningProcessplanningisinvolvedwiththedetailedsequenceofproductionstepsfromstarttofinish.Essentially,theprocessplandescribesthestateoftheworkplaceateachworkstation.Theuseofcomputersasanaidtoprocessplanningiscomparativelyrecentandhasledtoarebirthofwhatisknownasgrouptechnology(GT).Grouptechnologyisbasedonorganizingallsimilarpartsintofamiliestoallowstandardizationofmanufacturingsteps.Currentlyaprocessplanningsystemisunderdevelopmentanditisabletoproduceprocessplansdirectlyfromthegeometricmodeldatabasewithalmostnohumanassistance.Inthissystem,theprocessplannerwouldreviewtheimpactfromthedesignengineerviacommunicationandthenenterthisinputintotheCAMsystemwhichwouldgenerateacompletesetofprocessplansautomatically.RoboticManyadvancesarebeingmadetointegrateroboticsintoCAM.OneoftheseeffortsistheUSAirForceIntegratedComputer-Aided.Manufacturing(ICAM)project,ofwhichthegoalistoorganizeeverystepofmanufacturingaroundcomputerautomation.Aspartofthisprogram,arobotisusedtodrillsheetmetalaircraftparts.Therobotdrillsasetofholesto0.005intolerance,andmachinestheperimeterofanyoneof250typesofparts.Productionratesarefourtimesfasterthanconventionalmanualmanufacturing.FactoryManagementThisportionofCAMtiestogethertheotherareastocoordinateoperationsofanentirefactory.Themanagementsystemreliesheavilyongrouptechnologywithitsfamiliesofsimilarparts.Computersalsoperformvariousmanagementtaskssuchasinventorycontrolandmaterialrequirementsplanning(MRP)systems.NewWordsandExpressionsaircraft[eəkrɑːft]n.飞机，飞行器assistance[əsɪstəns]n.帮助，援助coded[kəʊdɪd]adj.编码的coordinate[kəʊ'ɔːdɪneɪt]v.协调database[deɪtəbeɪs]n.数据库drill[drɪl]n.钻头；v.钻(孔)，打(眼)essentially[ɪsenʃəlɪ]adv.本质上extract[ekstrækt]v.摘取，选取，提取n.摘录generality[dʒenərælətɪ]n.普遍性interface[ɪntəfeɪs]n.接口，接口处interpret[ɪntɜːprɪt]v.解释，翻译inventory[ɪnvəntrɪ]n.库存load[ləʊd]v.加载，装入程序machine[məʃiːn]v.以机器制造numerical[njuːmerɪkl]adj.数字的perimeter[pərɪmɪtə(r)]n.周边，周长previously['priːvɪəslɪ]adv.先前的，以前review[rɪvjuː]v.审查，回顾sequence[siːkwəns]n.系，一连串tolerance[tɒlərəns]n.(偏离标准的)容许误差，公差bedefinedas被定义为centrearound以……为中心，围绕relyon依赖，依靠Task5DiscusswithyourpartneraboutthebenefitsofapplicationofCAMinthefactory.Task6Pleasewriteoutthewordsinaccordingtotheirdefinitions.Thefirstlettersarealreadygiven.1.n_____relatingtonumbers;expressedinnumbers.2.g_____thequalityofbeinggeneralratherthandetailedorexact.3.c______toorganizethedifferentpartsofanactivityandthepeopleinvolvedinitsothatitworkswell.4.p______thetotallengthoftheoutsideedgeofanareaorashape.5.i______allthegoodsinashop.6.d______anorganizedsetofdatathatisstore