毕业设计英文翻译资料Word格式文档下载.docx
- 文档编号:924411
- 上传时间:2023-04-29
- 格式:DOCX
- 页数:43
- 大小:373.24KB
毕业设计英文翻译资料Word格式文档下载.docx
《毕业设计英文翻译资料Word格式文档下载.docx》由会员分享,可在线阅读,更多相关《毕业设计英文翻译资料Word格式文档下载.docx(43页珍藏版)》请在冰点文库上搜索。
MCanxixunInformationandNewsService
Contents
BasicsofMechanicalDesign2
(机械设计基础)2
AGuidetotheSelectionofLinearActuatorsforpositioningsystems(高小飞)2
Howtogetbettermotionwithplasticparts(王佳鹏)4
Hydraulicdrivescleanerair(杨海迎)7
Suppressioncircuitsforclutchesandbrakes(李慎龙)10
GettingENERGYSAVINGSfrompneumaticsystems(赵春)11
MechanicalManufacture&
Automation15
(机械制造与自动化)15
Whathappenswhenautomationsystemsfail?
(赵方英)15
Teamdevelopsrobotsystemstoremoveaircraftcoatings(赵方英)16
Machineinsertsdifferent-sizedpinsinthesameassembly(李臣光)17
WorldwideCNCMarketReturnsBig(李臣光)18
EasierMachineVision(李臣光)18
Mechatronics(机电一体化)20
Howtoavoidelectricalhazardswithairlogic(钟雨锋)20
What’supwithmodel-basedengineering?
(许博)22
Researcherslooktosimplifydynamicsystemsdesign(许博)23
Metal-facedinductivesensorsfordurability(张应志)24
Aerospace、MarineTech&
Application24
(海空技术与应用)24
Boeingcompletes737MAXconceptdevelopmentphase(张应志)25
Softwarecouldenablechangesearlyinaircraftdesignprocess(李帅)25
RockwellAutomationtosupplyPACsanddrivestoUSNavy(李帅)26
BasicsofMechanicalDesign
(机械设计基础)
AGuidetotheSelectionofLinearActuatorsforpositioningsystems(高小飞)
Specifyinglinearmotionsystemsisn’ttheblackartmanyengineersthinkitis.Thisarticleprovidessomeusefultipsandguidanceforengineersonhowtoselectthemostsuitablelinearactuatorsforsingleandmulti-axispositioningsystems.
Manyengineersarestillnotconfidentwhenitcomestoselectingsuitablelinearmotionsystemsforanapplication.Someengineersavoidlinearmotionsystemsaltogetherandreverttotheirtraditionalcomfortzoneofspecifyingrotaryalternatives,evenifthatmeansover-engineeringasolution.Inrealitythough,specifyinglinearmotionsystemsisnotthe‘blackart’thatmanyengineersthinkitis.
Onmostoccasions,ifengineersjustpickupthephoneanddiscusstheirapplicationwithalinearsystemssupplier,potentialissuescanusuallyberesolvedandasuitablesolutionfound.Bytalkingthroughtheirconcernswithanexperiencedlinearapplicationengineer,companiescanoftensavethemselvesalotofwasteddesigneffortorpreventthesystemfrombeingtoocostly(i.e.over-engineered).Thesuppliercanalsoinformthecustomerexactlywhatisandwhatisn’tpossibleintermsoflinearmotionsystemsandcanprovidevaluableadviceandguidanceonintegrateddrives,mountingarrangementsandfixings.
Inselectinglinearactuatorsforsingleandmulti-axishandling&
positioningsystems,terminologycanbeconfusing.Manyengineerscommonlyrefertolinearactuatorsas‘linearmodules’,‘drivenlinearsystems’or‘linearX-Ytables’.Thesetypesofsystems,whichwewillrefertoaslinearmodules,normallyincorporateanumberofdifferentlineardrivesandactuators,includingbelt-drivenlinearactuators,ballscrew-drivenlinearactuators,lineartablesandlinearmotors.
Thefactorsbelowneedcarefulconsiderationwhenselectingasuitablelinearmoduleforasingle-axis,two-axisorthree-axispositioningsystem:
SystemConfiguration
Systemconfiguration,includingthenumberofaxesofmotion,isoftenthefirstfactorthatneedscarefulthought.Themostcommonaretwo-axis(X-Y)configurations,butlesscomplexsingle-axisapplicationsandthree-axisconfigurationsarealsopossible.
Orientation&
Mounting
Systemorientationandmountingarealsokeyfactors.Inasingleaxislinearsystem,thisisfairlystraightforward,butinmultipleaxissystems,thisbecomesmorecomplex.Factorstoconsiderhereincludethedirectionoftravelofeachaxis.Doestheloadneedtobemovedsimultaneouslyinmultipleaxesordoeseachaxismoveindividually?
Doesthesystemrequireamovingcarriage(standard)oramovingrail?
Aretheaxesvertical,horizontalorinclined?
Arethemountingpositionsofeachactuatorat0,90or180degreestothehorizontal?
Otherfactorstoconsiderincludethespacingbetweensupportpointsinthesystem,aswellashowrigidandflatthesupportingsurfaceisfortheentirelinearpositioningsystem.
Mass&
CentreofGravity
Themass(andgeometry)oftheobjecttobemovedandthepositionofitscentreofgravityasitmovesrelativetoacoordinateordatumpointoneachaxismustalsobecalculated.Clearly,asamassisacceleratedordeceleratedalongmultipleaxesoftravel,thepositionofitscentreofgravityrelativetoeachaxiswillchange.Thisneedscarefulconsiderationsothatthemomentloadsatmultiplepointsinthesystemcanbeestablished.Often,calculatingthebestandworst-casescenarios(usingdesigncalculationsoftwaresuchasSchaeffler’sLinearEasySolution)andthenaveragingtheseissufficientformostapplications.
Otherquestionshereincludewhethersufficientloadcarryingcapacity(includingstaticsafetyfactors)hasbeenallowedinthesystemtocaterforinstantaneousmomentloads?
Also,arethereareanyoverhungloadsinthesystem,includingdrives,electricmotorsormotorisedgearboxes?
StrokeLengths
The‘effective’and‘total’strokelengthforeachaxisisalsocritical.Withballscrewdrivenlinearactuators,forexample,thestrokelengthislimitedtothelengthoftheballscrewitself.Therefore,maximumstrokelengthstendtobearound3metres.Butwithbelt-drivensystems,therearenosuchrestrictionsandsostrokelengthscanbehigherthanthis,uptoasmuchas20metresifrequired.Iflinearmotorsarespecified,intheory,strokelengthisunlimited,butinreality,lengthsabove10metresarerare.
Accuracy&
Repeatability
Dependingontheapplication,accuracyandrepeatabilitywilldiffergreatlybetweenapplications.Mostcustomersknowwhattheiraccuracyrequirementsarewhentheycontactus.Forexample,iftheactuatorisforanautomatedpick-and-placemachine,thenitislikelythathighrepeatabilityandaccuracyarerequired.Typically,theaccuracyofaballscrew-drivenlinearactuatoris0.16mmpermetrewithrepeatabilityof+/-0.01mm.Forbelt-drivenactuators,typicalaccuracyisaround0.5mmpermetre,withrepeatabilityof+/-0.10mm.
TraverseSpeeds&
Accelerations
Thelimitingfactorsfortraversespeedsandtraversetimesaretheballscrewsand/orthebearings.Typically,withballscrew-drivenactuators,maximumspeedsof3m/sarepossible.Forbelt-drivenactuatorswithtrackrollerguidancesystems,themaximumspeedisaround8-9m/s.Ifrecirculatinglinearbearingsareusedwithbelt-drivenactuators,maximumspeedsaresimilartotheirballscrewequivalents(i.e.3m/s).
Accelerationitselfisnotnormallythedefiningissueinmulti-axispositioningsystems.Itistheloadsduetotheseaccelerationsinthesystemthatarecritical.Thehighestaccelerationofanylinearactuatortodateisaround40m/s2,althoughtypicallyaccelerationsaremorelikelytobemuchlessthanthis,oftenbetween0.5m/s2and5m/s2.Decelerationisalsoimportant,particularlyifthereareemergencystopsrequiredinthesystem.
Cycletimerequirements
Cycletimesdictatethelifeofalinearsystem.Forexample,apositioningsystemsuchasatoolchangeronamachinetoolmightchangethetoolfivetimesperhour.Howisthiscycletimegoingtovaryfromday-to-dayandhowwillthisaffectthefatiguelifeofthelinearcomponentswithinthesystem?
Ifthecustomerneedsthesystemtolastforaminimumof10years,changingthetoolfivetimeseveryhourmaynotbeanissue.Butifthetoolischanged10timesperhour,adifferenttypeoflinearsystemmayberequiredinordertoguaranteea10-yearoperatinglife.
ExternalLoads&
Forces
Thisincludesexternalimpactforcesonthesystemsuchasstopsorhumaninterventions.Issomethingpushingorpullingontheloadtobemovedordoestheloadtobebroughtquicklytoastopattheendofitstravel?
Forexample,adrivemaybringthelinearactuatortoastopora‘home’datumposition.Howthisisachievedandhowthisaffectstheloadsonthemasstobemovedarekeyconsiderations.Asafetystrokefactormayalsoberequiredhere.
EnvironmentalFactors
Environmentalfactorssuchastemperature,humidityandcontamination(i.e.dust,oil,water,washdowns,chemicalsandcoolants,etc.)willalsoaffectthechoiceoflinearsystem.Adustyworkingenvironmentmayrequirethecustomertoimplementexternalbellowsordustextractiondevicesforthelinearsystem.Linearactuatorscanbeprotectedfromtheenvironmentbyincorporatingspecialseals,corrosion-resistantmaterialsandcoatings,specialgreasesorbyusingplasticpartswherenecessary.
Inmedicalapplications,theoverallnoiseofthesystemmaybeafactorthatneedsaddressing.Alowerspeedlinearactuatormaybethesolutionhere,butifhighspeedsneedtobemaintained,specialcomponents,materialsorcoatingsmayneedtobespecifiedinordertominimisenoiselevels.
ElectricalConsiderations
Formulti-axispositioningsystems,drivesandotherelectricalsystemsareoftencomplexandthereforerequirecarefulconsideration.Amulti-axislinearmoduleislikelytoincorporateelectricmotors,controllers,geareddrives,cables,grippers,limitswitches,encoders,brakesandothercontroldevices.
Howtogetbettermotionwithplasticparts(王佳鹏)
Polymerbearingsurfacesresistwear,don’tneedmaintenance,andcanrunsurprisinglyfast.
Engineersmightonlyglanceatthedimensionsandloadcapacitiesofrollerandcamfollowerstoensuretheywillfitintheirdesignbeforeplacinganorder.Buttheyshouldpaycloserattentionbecausethesecomponentscanmakeorbreaktheperfor
- 配套讲稿:
如PPT文件的首页显示word图标,表示该PPT已包含配套word讲稿。双击word图标可打开word文档。
- 特殊限制:
部分文档作品中含有的国旗、国徽等图片,仅作为作品整体效果示例展示,禁止商用。设计者仅对作品中独创性部分享有著作权。
- 关 键 词:
- 毕业设计 英文翻译 资料
![提示](https://static.bingdoc.com/images/bang_tan.gif)