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Machine design theoryThemachinedesignisthroughdesignsthenewproductorimprovestheold product to meet the human need the application technical science. Itinvolvestheprojecttechnologyeachdomain,mainlystudiestheproductthesize,theshapeandthedetailedstructurebasicidea,butalsomuststudytheproductthepersonnelwhichinaspecttheandsoonmanufacture,saleandusequestion.Carries on each kind of machine design work to be usually calleddesignsthepersonnelormachinedesignengineer.Themachinedesignisacreativework.Projectengineernotonlymusthavethecreativityinthework,butalsomustinaspectandsoonmechanicaldrawing,kinematics,engineerigmaterial, materials mechanics and machine manufacture technology has thedeepelementaryknowledge.Iffrontsues,themachinedesigngoalistheproductioncanmeetthehumanneedtheproduct.Theinvention,thediscoveryandtechnicalknowledgeitselfcertainlynotnecessarilycanbringtheadvantagetothehumanity,onlyhaswhentheyareappliedcanproduceontheproductthebenefit.Thus,shouldrealize to carries on before the design in a specific product, must firstdeterminewhetherthepeopledoneedthiskindofproductMustregard as the machine design is the machine design personnelcarriesonusingcreativeabilitytheproductdesign,thesystemanalysisandaformulation product manufacture technology good opportunity. Grasps theprojectelementaryknowledgetohavetomemorizesomedataandtheformulaismoreimportantthan.Themerelyservicedataandtheformulaisinsufficienttothecompletelydecisionwhichmakesinagooddesignneeds.Ontheotherhand,shouldbeearnestpreciselycarriesonalloperations.Forexample,evenifplaceswrongadecimalpointposition,alsocancausethecorrectdesigntoturnwronglyA good design personnel should dare to propose the new idea,moreoveriswillingtoundertakethecertainrisk,whenthenewmethodisnotsuitable,useoriginalmethod.Therefore,designsthepersonneltohavetohavetohavethepatience,becausespendsthetimeandtheendeavorcertainlycannotguarantee brings successfully. A brand-new design, the request screenabandons obsoletely many, knows very well the method for the people.Becausemanypersonofconservativeness,doesthiscertainlyisnotaneasymatter.Amechanicaldesignershouldunceasinglyexploretheimprovementexistingproductthemethod,shouldearnestlychooseoriginally,theprocessconfirmationprincipleofdesigninthisprocess,withhasnotunifieditaftertheconfirmationnewidea.Newlydesignsitselfcanhavethequestionoccurrencewhichmanyflawsandhasnotbeenabletoexpect,onlyhasaftertheseflawsandthequestionaresolved,canmanifestnewgoodscomeintothemarkettheproductsuperiority.Therefore,aperformancesuperiorproductisbornatthesametime,alsoisfollowingahigherrisk.Shouldemphasize,ifdesignsitselfdoesnotrequesttouse the brand-new method, is not unnecessary merely for the goal whichtransformtousethenewmethod.Inthedesignpreliminarystage,shouldallowtodesignthepersonnelfullyto display the creativity, not each kind of restraint. Even if has had manyimpracticalideas,alsocaninthedesignearlytime,namelyinfrontoftheplanblueprint is corrected. Only then, only then does not send to stops up theinnovation the mentality. Usually, must propose several sets of designproposals,thenperformthecomparison.Hasthepossibilityverymuchintheplanwhichfinallydesignated,hasusedcertainnotinplansomeideaswhichaccepts.How does the psychologist frequently discuss causes the machinewhich the people adapts them to operate. Designs personnels basicresponsibility is diligently causes the machine to adapt the people. Thiscertainlyisnotaneasywork,becausecertainlydoesnothavetoallpeopletosayinfactallisthemostsuperioroperatingareaandtheoperatingprocess.Anotherimportantquestion,projectengineermustbeabletocarryontheexchangeandtheconsultationwithotherconcernedpersonnel.Intheinitialstage, designs the personnel to have to carry on the exchange and theconsultationonthepreliminarydesignwiththeadministrativepersonnel,andisapproved.Thisgenerallyisthroughtheoraldiscussion,theschematicdiagramandthewritingmaterialcarrieson.Inordertocarryontheeffectiveexchange,needstosolvethefollowingproblem:(1) designs whether this product truly does need for the people?Whetherthereiscompetitiveability(2)doesthisproductcomparewithothercompaniesexistingsimilarproducts?(3)producesthiskindofproductiswhethereconomical?(4)productserviceiswhetherconvenient?(5)productwhetherthereissale?Whethermaygain?Only has the time to be able to produce the correct answer to abovequestion.But,theproductdesign,themanufactureandthesaleonlycanincarryontotheabovequestionpreliminaryaffirmationanswerfoundationin.Project engineer also should through the detail drawing and the assemblydrawing,carriesontheconsultationtogetherwiththebranchofmanufacturetothefinallydesignproposalUsually,canhavesomeprobleminthemanufactureprocess.Possiblycanrequesttosomecomponentssizeorthecommondifferencemakessomechanges,causesthecomponentstheproductiontochangeeasily.But,intheprojectchangemusthavetopassthroughdesignsthepersonneltoauthorize,guaranteedcannotdamagetheproductthefunction.Sometimes,wheninfrontofproductassemblyorinthepackingforeignshipmentexperimentonlythendiscoversinthedesignsomekindofflaw.Theseinstancesexactlyshowedthedesign is a dynamic process. Always has a better method to complete thedesign work, designs the personnel to be supposed unceasingly diligently,seeksthesebettermethod.Recent year, the engineerig material choice already appearedimportantly. In addition, the choice process should be to the materialcontinuously the unceasing again appraisal process. The new materialunceasingly appears, but some original materials can obtain the quantitypossibly can reduce. The environmental pollution, material recycling aspectand so on use, workers health and security frequently can attach the newlimitingconditiontothechoiceofmaterial.Inordertoreducetheweightorsavestheenergy,possiblycanrequesttheusedifferentmaterial.Comesfromdomestic and international competition, to product service maintenanceconvenience request enhancement and customers aspect the and so onfeedbackpressure,canurgethepeopletocarryontothematerialreappraises.Becausethematerialdoesnotselectwhencreatedtheproductresponsibilitylawsuit,hasalreadyhadtheprofoundinfluence.Inaddition,thematerialandbetween the material processing interdependence is already known by thepeopleclearly.Therefore, inordertocanandguaranteesthe qualityinthereasonable cost under the premise to obtain satisfaction the result, projectengineer makes engineers all to have earnestly carefully to choose, thedeterminationandtheusematerial.Makes any product the first step of work all is designs. Designsusually may divide into several explicit stages: (a) preliminary design; (b)functionaldesign;(c)productiondesign.Inthepreliminarydesignstage,thedesigneremphaticallyconsideredthe productshouldhave function.Usuallymustconceiveandconsiderseveralplans,thendecidedthiskindofthoughtiswhetherfeasible;Ifisfeasible,thenshouldmakesthefurtherimprovementtoorseveralplans.Inthisstage,thequestionwhichonlymustconsideraboutthechoiceofmaterialis:Whetherhastheperformancetoconformtotherequestmaterial to be possible to supply the choice; If no, whether has a biggerassuranceallpermitsinthecostandthetimeinthelimitdevelopsonekindofnewmaterial.Inthefunctionaldesignandtheengineeringdesignstage,needstomakeapracticalfeasibledesign.Mustdrawupthequitecompleteblueprintinthis stage, chooses and determines each kind of components the material.Usuallymustmaketheprototypeortheworkingmodel,andcarriesontheexperiment to it, the appraisal product function, the reliability, the outwardappearance and the service maintenance and so on. Although this kind ofexperimentpossiblycanindicate,entersintheproducttotheproductionbaseinfrontof,shouldreplacecertainmaterials,but,absolutelycannotthispointtakenotearnestlychoosesthematerialtheexcuse.Shouldunifytheproductthefunction,earnestlycarefullyconsiderstheproducttheoutwardappearance,thecostandthereliability.Hastheachievementverymuchthecompanywhenmanufactureallprototypes,selectsthematerialshouldthematerialwhichuseswithitsproductioninbesame,andusesthesimilarmanufacturetechnologyasfaraspossible.Likethishastheadvantageverymuchtothecompany.Thefunctioncomplete prototype ifcannotactaccordingtotheanticipatedsalesvolumeeconomicallytomake,orisprototypicalandtheofficialproductioninstallmenthasinthequalityandthereliableaspectisverygreatlydifferent,thenthiskindofprototypedoesnothavethegreatvalue.Projectengineerisbestcancompletelycompletethematerialinthisstagetheanalysis,thechoiceandthedeterminationwork,butisnotremainsittotheproductiondesignstagedoes.Because,iscarriesonintheproductiondesignstagematerialreplacementbyotherpeople,thesepeopleareinferiortoprojectengineertotheproductallfunctionsunderstanding.Intheproductiondesignstage,isshouldcompletelydeterminewiththematerialrelatedmainquestionthematerial,causesthemtoadapt with the existing equipment, can use the existing equipmenteconomicallytocarryontheprocessing,moreoverthematerialquantitycanquitebeeasytoguaranteethesupply.Inthemanufactureprocess,inevitablycanappeartousesthematerialtomakesomechangesthesituation.Theexperienceindicatedthat,mayusecertain cheap materials to take the substitute. However, in the majoritysituation,inwillcarryontheproductionlatertochangethematerialtohaveintostartbeforetheproductiontochangethepricewhichthematerialwillspendtohavetobehigherthan.Completesthechoiceofmaterialworkinthedesignstage, may avoid the most such situations. Started after the productionmanufacturetoappearhasbeenpossibletosupplytheusethenewmaterialisreplacesthematerialthemostcommonreason.Certainly,thesenewmaterialspossibly reduce the cost, the improvement product performance. But, mustcarry on the earnest appraisal to the new material, guarantees its allperformancealltoanswerthepurpose.Mustrememberthat,thenewmaterialperformance and the reliable very few pictures materials on hand suchunderstoodforthepeople.Themajorityofproductsexpirationandtheproductaccidentcausedbynegligencecaseisbecauseinselectsthenewmaterialtotake in front of substitution material, not truly understood their long-termoperationalperformancecauses.Theproductresponsibilitylawsuitforcesdesignsthepersonnelandthecompanywhenthechoicematerial,usesthebestprocedure.Inthematerialprocess,fivemostcommonquestionsare:(a)didnotunderstandorcannotuseaboutthematerialapplicationaspectmostnewlythebestinformationpaper;(b)hasnotbeenabletoforeseeandtoconsidertheduskyearpossiblereasonableuse (for example to have the possibility, designs the personnel also to besupposedfurth