機械原理課程設計模板

機械原理課程設計資料內(nèi)容僅供參考，如有不當或者侵權，請聯(lián)系本人改正或者刪除。機械原理課程設計說明書——自卸車傾卸機構創(chuàng)新設計學院:機械工程學院班級:組員:指導教師:二〇一三年一月四日摘要我們組選擇自卸車傾卸機構的創(chuàng)新設計作為課程設計的題目.為了完成課程設計,我們首先查找了關于自卸車傾卸機構的發(fā)展史,了解了自卸車的發(fā)展歷程與現(xiàn)狀.然后我們查找了關于自卸的國內(nèi)外專利,并分析其機構,畫出機構簡圖.知道了自卸車有各種不同的機構,并了解了現(xiàn)在常見的自卸機構以及自卸機構未來的發(fā)展趨勢.為了創(chuàng)新設計,我們現(xiàn)場對常見自卸車的自卸機構拍照.分析機構,并進行了運動鏈的一般化,數(shù)綜合,特定化和具體化等一系列過程.最后得出27個可能的機構簡圖.在進行比較時,我們選擇了一個不是當前流行類型的機構簡圖作為自己的創(chuàng)新設計.按對自卸車較為常見的要求:車斗最大傾角,機構縱深,液壓缸伸縮距離,結(jié)構合理等,我們設計了創(chuàng)新機構的尺寸.在用inventor對其進行運動仿真后,發(fā)現(xiàn)結(jié)構運動平穩(wěn).然后我們又用matlab對機構進行建模,仿真.得出機構的角速度,角加速度等圖形.發(fā)現(xiàn)機構角速度變化幅度不大,符合仿真動畫,滿足實際要求,因此,我們確定了我們的創(chuàng)新設計符合要求并將其作為最終的課程設計的方案.AbstractOurgroupchoosesdumptruckdumpingmechanisminnovationdesignascurriculumdesignquestions.Inordertocompletethecoursedesign,wefirstlookforthedumptruckdumpingmechanismaboutthehistoryofthedumptruck,understandthedevelopmentcourseandpresentsituation.Thenwefindaboutdumpingdomesticandforeignpatents,andanalyzesthemechanism,drawthemechanismdiagram.Knowthedumptruck,thereareallkindsofdifferentorganizations,andtounderstandthepresentcommonlyusedself-discharginginstitutionsandself-dischargingmechanismthefuturetrendofdevelopment.Inordertocreativedesign,oursitetothecommondumper'sself-dischargingmechanismphotos.Bodyanalysisandthekinematicchainofgeneralization,severalcomprehensive,specializationandshapeandaseriesofprocessthat.Atlast,wegive27possiblemechanismdiagrams.Incomparison,wechoseanotcurrentpopulartypeofmechanismdiagramastheirinnovativedesign.Accordingtotherequirementsofthemorecommontodumptruck,carbucketmaximumAngleofinclination,theagencydepth,hydrauliccylinderexpansiondistance,reasonablestructureandsoon,wedesigntheinnovationorganizationinthesizeoftheinventor.Themotionsimulation,foundthatthesmoothmovementstructure.ThenweuseMATLABtomechanismmodeling,simulation.Drawmechanismofangularvelocity,angularaccelerationandangularvelocitychangegraphics.Findinstitutionsrangeisnottoomuch,inlinewiththesimulationanimation,meetthepracticalrequirements,therefore,wedetermineourinnovativedesignmeettherequirementsastheirfinalcoursedesignscheme.目錄一、 題目簡介 11. 題目描述 12. 原始數(shù)據(jù)和設計規(guī)格 2二、 現(xiàn)有機構分析 21. 文獻綜述 22. LiteratureReview 43. 現(xiàn)有機構分析 6三、 機構創(chuàng)新（CreativeMechanismDesignMethodology） 171. BriefDiagramofthePrototype: 172. Generalization: 173. Numbersynthesis 174. Specialization 175. Particularization: 24四、 尺寸設計 261. 尺寸設計 262. 設計圖 27五、 機構分析與仿真 281. Inventor仿真圖像 282. Matlab仿真過程 28六、 總結(jié) 33七、 Reference 34八、 附錄 351. MATLAB程序代碼： 35題目簡介題目描述自卸車是一種經(jīng)過車自身的傾卸機構,能夠?qū)④嚩分胸浳飪A卸出去的一種車。自卸車傾卸機構的創(chuàng)新設計就是對現(xiàn)有的自卸機構進行創(chuàng)新再設計,使其滿足自卸的使用要求。平穩(wěn)傾卸貨物。如下圖中,液壓缸作為動力原件,液壓缸的伸縮,經(jīng)過六桿機構的轉(zhuǎn)換,使車斗傾斜,達到傾卸貨物的目的。自卸車圖片PicturesofaDumpTruck圖1自卸車機構簡圖BriefDiagramoftheDumpTruck圖2DOF=3n-2Pl-Ph=3x5-2x7=1原始數(shù)據(jù)和設計規(guī)格選小車型設計,車斗長5米左右.為使貨物傾卸完全,車斗最大傾角應在45~70度,能夠選擇60度.單級液壓缸,最大伸縮長度在0.5~0.8m.機構縱深約為0.5m.現(xiàn)有機構分析文獻綜述最早的自卸車是以馬拉的形式的二輪裝卸車,貨物重心在二輪車的輪軸上,當裝載貨物時,只需要放到軸上就能夠了,貨物前方用繩子勾住固定;卸載時傾卸車即可。這種二輪車曾用在開放礦場,用馬匹拉著在鐵軌上行走。1900之后,一種四輪的馬拉式平板自卸車誕生,它帶有一個矩形貨物箱,經(jīng)過車前的繩子來實現(xiàn)傾卸。早期的馬拉式自卸車最早出現(xiàn)的自卸車車身是根據(jù)裝卸重心位置的原則設計的,這種車最早出現(xiàn)在19,那時曼式重力傾卸機構在英國出現(xiàn)。液壓傾斜機構自卸車液壓力學運用在較早的馬拉式自卸車上,根據(jù)記載表明,一種最早的液壓傾斜機構運用在羅伯遜汽車上,它帶有一個液壓起重機,能夠從汽車的發(fā)動機或者一個獨立的蒸汽機里獲得動力。Alley&McLellanofGlasgow在19創(chuàng)造了早期的依靠蒸汽驅(qū)動的液壓傾斜機構。履帶式拖車在19世紀20年代中期,履帶式拖車牽引輪式自卸車迅速流行。有時拖車能夠拉兩到五個附加拖車,很多公司開始發(fā)展可附加式拖車。最早的拖車是運行在軌道上的,可是當速度越來越受到限制時,開始使用輪胎來提高速度。這種軌道式拖車的創(chuàng)造者有Euclid,JamesHagy,LaPlant-Choate,Rex-Watson,andStreich和Western。Euclid自卸車Euclid是自卸車發(fā)展的先驅(qū)者。GeorgeArmington的兒子GeorgeArmingtonJr.設計和制作了兩種對世界自卸車有重大意義的創(chuàng)造,包括現(xiàn)代重型越野卡車和輪式拖車置底傾斜車。1934年,這個公司創(chuàng)造了10/11噸級自卸車,名為"TrakTruk."。它是第一個用來重型越野服務的后卸式自卸車,后來又創(chuàng)造了15噸級的自卸車,得到很大的改進。19世紀50年代的自卸車到了19世紀40年代,自卸車的科技發(fā)展達到了一個新的高度,截至19世紀50年代,美國已經(jīng)創(chuàng)造了置底式自卸車,1951年,Euclid公司制作出世界上最大的自卸車1LLD。1954年Komatsu公司制作出時速為42千米凈載重為13.60噸的輪式自卸車。1958年,自卸車市場上最大馬力的單獨發(fā)動機為AP40,可達600馬力。RalphH.Kress和HaulpakRalphH.Kress以她創(chuàng)造的前置式自卸車,重型越野自卸車在礦場的運用而聞名于整個自卸車的世界。1955年,作為WABCO(現(xiàn)在是Komatsu)的創(chuàng)始者,她致力于可縮短軸距擁有深、斜、平特點的車身的設計,它就是Haulpak,被視為量子發(fā)展設計。最早的Haulpak于1957年在市場上出現(xiàn),它能夠有32噸級的凈載量,后來發(fā)展為75噸級。這些最早的自卸車噸級范圍為25到32噸級,由于太小而廣泛應用于礦場。Haulpak最終由于在尺寸上的發(fā)展,成為表面礦場工業(yè)的選擇。專利綜述當前,自卸車從單純的5噸自卸車逐漸向更高噸位的方向發(fā)展,舉升機構也從簡單的單級缸中置直頂式、多級缸中置直頂式向單級缸連桿組合式、多級缸前置直頂式的方向發(fā)展。液壓傾斜機構是自卸車的核心,是判別自卸車優(yōu)劣的首要指標。不同的舉升機構,有不同的車型定位和市場定位。從美國專利局所查找的專利中我們能夠看到大部分自卸車為單杠連桿組合式,例如US2849255,US3172703,US3620458orso.US4036528。US6382731運用多級缸中置直頂式。下面是各個形式舉升機構的優(yōu)缺點。單級缸中置直頂式舉升機構——是最早出現(xiàn)的舉升機構,機構簡單,緊湊,受力直觀,而且成本低廉,在載重量為5噸或者5噸以下的自卸車中普遍采用。US4036528運用此機構。多級缸中置直頂式舉升機構——為了改進單級缸直頂式舉升機構的弱點,多級缸中置直頂式舉升機構應運而生。它極大改進了油缸和副車架的使用環(huán)境,使油缸和副車架的手里很小,使整個液壓系統(tǒng)的使用壽命大大延長。而且,由于多級缸是套筒式的結(jié)構,內(nèi)瀉量小。缺點是在布置上比較困難,液壓系統(tǒng)過于復雜。在國內(nèi)一般不被使用。專利US4056283。單級缸連桿組合式舉升機構——有升平穩(wěn),超載能力強,系統(tǒng)液壓性能好等特點,因而被各大汽車改裝廠采用,經(jīng)過對四桿機構的優(yōu)化設計,能夠設計出多種連桿組合式機構。馬進里式和油缸浮動式采用較多,其它由于具有缸徑大,油缸行程短等因素采用過的較少。專利US4168861。多級缸前置直頂式舉升機構——主要由一支多節(jié)缸組成,行程大5~6米,能夠把重心將到最低,極大的改進了車輛的穩(wěn)定性。由于該機構受力最簡單,最省力,因此,采用多級缸前置直頂式舉升機構的自卸車是今后重型自卸車的發(fā)展方向?？墒怯袃牲c缺點,一是成本最昂貴,二是它的油缸行程過,三是控制系統(tǒng)過于靈敏。當前國內(nèi)生產(chǎn)這種機構的不多。專利US5033794,US6382731。國內(nèi)自卸車發(fā)展前景當前國內(nèi)自卸車發(fā)展主要受到兩個問題的影響:大重力重心和重型載重。國內(nèi)大部分自卸車運用了單級缸連桿組合式舉升機構,在發(fā)展趨勢為多級缸前置直頂式舉升機構的前提下,盡管國內(nèi)運用很少,可是我們相信,在不久的將來,它一定會迅速發(fā)展起來。

LiteratureReviewTheveryfirstversionofadumptruckusedtohaulanddumpmaterialwasnothingmorethanasimpledumpbodystylecartdrawnbyhorses.Itwouldhaveconsistedofatwo-wheeledcarthinged圖3totheaxlewiththecenterofgravity,whenloaded,justbehindtheaxle.Theloadedfrontbodywashooked,andwhenunlatched,woulddump.Thesecartswereusedinopenminesandpulledbyhorsesalongarailwaytrack.After1900,afour-wheeledhorse-drawnflatbedwagonwitharectangularbodyliftedwithahandhoistinthefrontwasemployed.EarlyTruckMountedDumpBodiesTheearliestversionsoftruckmounteddumpbodiesreliedontheprincipleofgravityfordumping.Someofthefirsttruckswithdumpbodiesdesignedonthisprincipleappearedasearlyas1904whentheManngravitydumpwasbuiltinEngland.HydraulicDumpBodiesHydraulicswasbeingincorporatedintotruckmounteddumpbodiesrelativelyearlyon.RecordsshowthatoneofthefirsthydraulicdumpbodieswastheRobertsonSteamWagonwithahydraulichoistthatreceivedpowerfromthetruck’sengineoranindependentsteamengine.Alley&McLellanofGlasgowdevelopedanotherearlyhydraulicdumpbodyin1907thatwaspower-drivenbysteam.CrawlerTractor-trailersInthemiddleofthe1920s,crawlertractorspullingheavydumptrailersmountedonwheelsortrackswerebecomingincreasinglypopular.Sometimescrawlerswouldpulltwotofiveattachedtrailers.Companiesbegandevelopingwagonsspecificallydesignedforattachmenttocrawlertractors.Thefirstversionsweremountedontracks;however,whenspeedrestrictionsposedaproblem,thewagonsweremountedonwheelstoimprovespeed.ManufacturersofsuchtrailersandhaulersincludedEuclid,JamesHagy,LaPlant-Choate,Rex-Watson,andStreichandWestern.EuclidDumpTrucksEuclidwasapioneerinthedevelopmentofdumptrucks.GeorgeArmingtonJr.,sonoffounderGeorgeArmington,wasahydraulicsdesignerandmadetwosignificantcontributionstotheworldofdumptrucks.Theseincludedthemodernheavydutyoff-highwaytruckandthewheeltractorbottomdumpwagon.In1934thecompanyintroducedits10/11-tondumptruckcalledthe"TrakTruk."Itwasthefirstrear-dumptruckthatwasdesignedforheavy-dutyoffroadservice.Thiswasfollowedupin1936withthecompany’s15-tonModelIFDtruckthatfeaturedadieselengine,moderndriveline,planetaryfinaldrives,leaf-springsuspension,andpneumatictires.Thetruckreplacedheavy,gasolinepoweredchaindriveMacktrucksthathadpreviouslybeenusedforstandardworkinconstructionandminingoperations.DumpTrucksinthe1950sBythe1940sthetechnologicaldevelopmentofdumptruckshadreacheditspeak.IntheU.S.,bottomdumptruckswerealreadydominatingearthmovingsitesbythe1950s.Thedecadecontinuedtomarkaproliferationinthemanufacturingofdumptrucks.In1951,forexample,Euclidproducedtheworld’slargestdumptruckwhenitmanufacturedthe1LLD.In1954Komatsubuiltthefirstdumptruckonwheelsthattraveledat26miles(42km)perhourandhada13.60-tonpayload.In1958,the600horsepowerAP40Autocarwasthelargestsingleenginedumptruckonthemarket.RalphH.KressandtheHaulpakRalphKressisperhapsbestknowninthedumptruckworldforpioneeringandbringingdumptrucktechnologytotheforefront,inparticular,heavy-duty,off-roaddumptrucksusedinmining.In1955,asaconsultantforWABCO(nowKomatsu),hewasinstrumentalinconfiguringadumptruckthatincorporatedashortwheelbaseandhadahighangleofturnwithadeep,sloped,flatbodyknownasaHaulpakandwasviewedasthe”quantumadvanceindesign”withitshydro-pneumatic”Hydrair”struts.ThefirstversionsoftheHaulpakweremadeavailabletothemarketin1957featuring25-to32-tonpayloadcapacitiesandwereeventuallymarketedandusedastractorstopullsupplementary75-tontrailers.Theseearlierversions,rangingfrom25-to32-tonrangecapacity,weretoosmallinitiallytobeusedinopenpitminesbutgainedacceptancefromcontractors.EventuallyHaulpakgrewinsizeandbecamethedumptruckofchoiceinthesurfaceminingindustry.TheHaulpakwouldexistasthestandardtowhichotheroff-highwaydumptruckswouldcometobedesigned.

現(xiàn)有機構分析(1)專利綜述PatentReviewThedumptruck,asonethelargestspecialvehicles,isdevelopingfromthe5tdumptrucktomoretons.Thecoreofadumptruckistheliftingmechanism,whichdevelopsfromthesinglecylindercentrally-mountedstraighttoptypeandthemultistagecylindercentrally-mountedstraighttoptypetothesinglecylinderconnectingrodcombinedtypeandthemultistagecylinderleadstraighttoptype.FromthepatentsamongthesearchingresultsfromtheUSpatentandtrademarkoffice,wecanseethatmostofthetrucksaredesignedwiththesinglecylinderconnectingrodcombinedtypesuchasUS2849255,US3172703,US3620458orso.US4036528usesthesinglecylindercentrally-mountedstraighttoptype.US6382731usesthemultistagecylinderleadstraighttoptype.Herearesomeadvantagesanddisadvantagesofthefourtypeofthedumpingmechanism:Thesinglecylindercentrally-mountedstraighttoptype——itisthepioneeroftheliftingmechanismofthedumptruck.Itsstructureisverysimpleandtightanditscostislow,butitsloadisverysmallsothatitisusedasthetrucksbelow5t.Itiswidelyusedaslight-weighttrucks,forexampleDongfeng3092Fusesthisliftingmechanism.SeePatent:US4036528.圖4Themultistagecylindercentrally-mountedstraighttoptype——itimprovesthedisadvantagesofthesinglecylindercentrally-mountedstraighttoptype.Itimprovestheconditionofthecylinderandtheframetoextendtheirlifetimeandreducestheinsidedischargeofthecylinder.Buttheframeworkdesignisdifficult.Itmakesthehydraulicsystemcomplexandcostsalot,soitisnotcommonlyused.SeePatent:US4056283.圖5Thesinglecylinderconnectingrodcombinedtype——ithasthestableliftingability,strongoverloadingabilityandgoodhydrauliccharacteristics.Itcanbechangedintodifferentstylethroughchangingthefour-barlinkage.MallorytypeisoneofthetypesandwidelyusedinChinabecauseofthecharacteristicsofsmallcylinderdiametersandlongcylinderroutes.Butsometypesisnotwidelyusedbecauseofbigcylinderdiametersandshortcylinderroutes.SeePatent:US4168861.圖6Themultistagecylinderleadstraighttoptype——ismadeupofonemultistagecylinderwhoseroutecanbe5to6meters.Itisthesimplestliftingmechanismandlargelyimprovesthestabilityofthetruck.Itisthedevelopmentdirectionofthedumptruck.Butitscostisthemostexpensive,whichrestrictsitsdevelopmentinChina.SeePatent:US5033794,US6382731.圖7ThefutureofDumpTrucksinChinaMostofthedumptrucksinChinausethesinglecylinderconnectingrodcombinedtype,fromthesinglecylindercentrally-mountedstraighttoptypeandthemultistagecylindercentrally-mountedstraighttoptype.Thetrendofdevelopmentisthemultistagecylinderleadstraighttoptypeandthetypewillbedeveloped,butwecan’tseealotinChina.Webelieveinthedistantfutureitcanquicklybedevelopedandusedinourcountry. Thefrontmulti-levelcylinderliftingmechanismistheleadingdirectionofdumptruckmanufacturing.Fornow,thedumptrucksinourcountryarebotheredbytwomainproblems:highgravitycenterandheavydeadweight.Toovercomethesetwoobstacles,theyoungergenerationandthetechnicalengineersneedtoworkhardtoimprovethecompetingabilityofourproduction.Allinall,thekeypointistoimprovethequalityofourproducts.

(2)專利列表PatentListPatentNo.AppTimePatentNameInventorDrawingFiguresBriefDiagramTheTypesUS20945211935.10.11LIFTINGMECHANISMFORDUMPBODIESF.BISZANTZetalInventionPatent;Eight-barLinkageUS24492021946.11.8HYDRAULICACTUATINGMECHANISMFORDUMPTRUCKSClaims.(CletalInventionPatent;Four-barLinkageUS25937761950.3.21DUMPBODYTILTINGMECHANISMCharlesE.MargalaetalInventionPatent;Six-barLinkageUS28492551955.8.16HOISTMECHANISMFORDUMPTRUCKSGeraldJ.PaskeretalInventionPatent;Six-barLinkageUS31727031963.6.14DUMPMECHANISMFORTRUCKSJoanA.ByerInventionPatent;Six-barLinkageUS35128361968.10.9LATERALSTABILIZINGMEANSFORASEMI-TRAILERDUMPBODYAnthonyPolicfaetalInventionPatent;Eight-barLinkageUS36204581970.4.21ALBERTRATHXYSteelProductsLtd.PrestonetalUtilityModelPatent;Six-barLinkageUS40365281975.10.14TruckwithtiltablebodyHeinrichLangendorfInventionPatent;Four-barLinkageUS40493161976.1.29LiftingmechanismsfortruckbodiesMarinoPanedaOrdonezInventionPatent;Six-barLinkageUS40521051976.4.9TruckhoistWalterMoeInventionPatent;Six-barLinkageUS40662961976.12.28TruckbedtiltingmechanismLouisM.Ray,Jr.etalInventionPatent;Six-barLinkageUS40562831977.1.25TruckconstructionRobertMarvinPowUtilityModelPatent;Six-barLinkageUS41688611978.2.6Dump-hoistconversionsystemOllieJ.CarrollUtilityModelPatent;Six-barLinkageUS43020501979.10.17TruckhoistEldonD.JonesUtilityModelPatent;Six-barLinkageUS43826321982.6.10DumpingvehiclestabilizersystemCharlieC.PittsUtilityModelPatent;Six-barLinkageUS45317801982.9.3LiftmechanismforadumptruckBruceM.BoczkiewiczUtilityModelPatent;Six-barLinkageUS45925931984.5.4ScissorframeliftapparatusfordumptrucksGlennL.ChannellInventionPatent;Six-barLinkageUS50488961988.4.20MinimumprofilehoistGlennL.ChannellUtilityModelPatent;Six-barLinkageUS50337941990.10.18SecuringdevicefordumptruckHenryL.VickUtilityModelPatent;Four-barLinkageUS52036681991.6.6Apparatusforloadingandunloadingofacontainerstructureorotherloads...LazarMarmurUtilityModelPatent;Six-barLinkageUS51953851991.10.28Freerangingbi-directionalhydraulicdumpingmechanismJeromeA.JohnsonUtilityModelPatent;Six-barLinkageUSRE347331992.8.5ScissorframeliftapparatusfordumptrucksGlennL.ChannellUtilityModelPatent;Six-barLinkageUS55139011994.3.14HoistmechanismFredP.SmithetaInventionPatent;Eight-barLinkageUS59677331997.12.12HydraulictilttrailerRussellCashUtilityModelPatent;Six-barLinkageUS61565961999.3.11TruckhoistEldonD.JonesUtilityModelPatent;Six-barLinkageUS6382731.6.26LoadhaulingvehiclewithsidewallraisingandloweringmechanismMichaelSlutzetalUtilityModelPatent;Six-barLinkageUS6663185.11.13TippingtrailersRhysWilliamRichardsUtilityModelPatent;Six-barLinkageUS7770980.5.1DumpvehicleJamesP.Godwin,Sr.etalUtilityModelPatent;Four-barLinkageUS7523994.6.20HoistEldonD.JonesUtilityModelPatent;Six-barLinkageUS7695237.8.8RefusecollectionvehicleandliftingapparatusthereforKostiShirvanianUtilityModelPatent;Six-barLinkageUS8157316.1.29TranslatingcargobedHarlanJ.BartelInventionPatent;Fourteen-barLinkage

機構創(chuàng)新(CreativeMechanismDesignMethodology)BriefDiagramofthePrototype:Generalization:Theprototypeisasix-barlinkage,thekinematicchaincanberegeneratedinto”Stephenson’slinkage”:NumbersynthesisThereareonlytwoeffectiveonescalledWatt’slinkageandStephenson’slinkageStephenson’slinkageWatt’slinkageSpecializationRequirementsandconstrains:(1)Onelinkhastobethebody(groundlink).(2)TheboxhastobeasidelinkandthelinkagehastobeaRevoluteJoint.(3)Onelinkhastobethedrivinglink;consideringthedemandofhugepower,thedrivinglinkmustbehydraulic.(4)AlllinkageshavetobeRevoluteJointsexceptthedrivinglink(thehydrauliccylinder).(4)Box,drivinglinkandthegroundcouldnotbeinthesamekinematicchaincircuittoavoidfour-barlinkagewhichmayaffectliftingqualityandstability.A:Followingarethe9possiblesolutionsaccordingto1and2:車身車身車斗車斗車斗車斗車身車身車身車身車斗車斗車身車身車斗車斗車斗車斗車身車身車身車身車斗車斗a)b)c)d)e)f)車身車身車斗車斗車斗車身Box車身車身車斗車斗車斗車身Boxg)h)i)B:Drivinglink(Prismaticpair)Followingarethe9possiblesolutionsaccordingto3,4and5:底盤車斗車斗底盤底盤車斗車斗底盤A1A2車斗底盤車斗底盤車斗底盤車斗底盤A3B1底盤底盤車斗車斗底盤底盤車斗車斗B2B3底盤車斗車斗底盤底盤車斗車斗底盤B4C1底盤車斗車斗底盤底盤車斗車斗底盤C2C3底盤車斗底盤車斗底盤車斗底盤車斗D1D2車斗底盤車斗底盤車斗底盤車斗底盤D3D4底盤底盤車斗車斗底盤底盤車斗車斗E1E2車斗車斗底盤底盤車斗車斗底盤底盤E3E4底盤車斗底盤車斗底盤車斗底盤車斗F1F2車斗車斗底盤底盤車斗車斗底盤底盤F3H1車斗車斗底盤底盤車斗車斗底盤底盤H2H3車斗車斗底盤底盤車斗車斗底盤底盤I1I2車斗底盤車斗底盤I3Particularization:FollowingaretheparticularizationofA1,D1andF2圖8A1圖9D1圖10F2

尺寸設計尺寸設計以機構簡圖F2作為創(chuàng)新設計的機構。FBA3C2D14EFBA3C2D14E圖11選取F2作為創(chuàng)新設計的機構的優(yōu)勢:(1)能夠經(jīng)過較小的液壓缸行程獲得較大的車斗角度變化(2)機構縱深較小,便于整車重心下降,提高產(chǎn)品競爭力(3)主動件等效力臂較長,在相同液壓缸驅(qū)動力下力矩較大,機構負載能力強(4)經(jīng)過估算發(fā)現(xiàn),車斗舉升角速度平穩(wěn),卸貨穩(wěn)定設計圖θ3B(B’)F(F’)HD’E’θ2D液壓桿L2CC’EL3A(A’)初始位置L4θB(B’)F(F’)HD’E’θD液壓桿L2CC’EL3A(A’)初始位置L4L1最終位置圖12參數(shù)選擇:(1)車斗初始位置水平,為了使重物傾斜完,傾角需要45°至70°,在創(chuàng)新機構中選擇最大傾角為60°(2)根據(jù)實際車的尺寸大小,按車斗長4.8m,選擇中間作為機構力的作用點,因此選取車斗的一半L1=2.4m(3)自卸車要求建造縱深盡可能小,因此使B點與A點在同一水平位置,F點與AB所在水平位置高度差,即BH盡可能小。按一般自卸車常見尺寸選擇建造縱深為0.4m。由圖可知連桿L2大致為0.5m,在沒有精確要求的情況下,可選擇L2=0.5m(4)由L4>L1sin60°-L2=1.578m.為了使車斗在提升過程中受力較大,需要連桿L2與車斗形成較大的銳角。因此選擇連架桿L4=1.8m。此時可取BE=0.8m,L3=0.8m(4)采取一級液壓伸縮機構,因此有EF=2E’F,由EE’=1.06m,取E’E垂直于E’F,則計算得E’E=0.61m,EF=1.22m。同時能夠計算得到BH=0.48m,FH=0.22m(5)由公式:L1cos60°+L2cosθ2=L4+L3cosL1=L2sinθ2+L3sin(6)解得:θ2=56.41°,θ3=67.92°。

機構分析與仿真Inventor仿真圖像圖13液壓桿速度為3cm/s,圖示為車斗前端一點的位置,速度及加速度圖像。圖中顯示速度和加速度基本不變,因此能夠看出車斗運行平穩(wěn),故該創(chuàng)新機構符合實際要求。Matlab仿真過程由液壓桿和L4桿所在四桿機構分析出L4水平角(逆時針旋轉(zhuǎn))與液壓桿長ganlength關系F1:F1(液壓桿長ganlength)=L4水平角度再由L4桿和車斗L1桿所在四桿機構分析出兩者水平角關系F2:F2(L4水平角)=L1水平角F1和F2關聯(lián)得到液壓桿長ganlength和L1水平角的關系F3:F3(液壓桿長ganlength)=L1水平角根據(jù)F3,以及壓桿長ganlength=液壓桿伸縮速度v*時間t,得到L1水平角-時間t關系F4,并做出擬合曲線(單次升程使用plotfit函數(shù)線性擬合,全程使用cftool擬合工具中的8級傅立葉擬合):F4(時間t)=L1水平角即角度-時間函數(shù),作圖一次求導(diff函數(shù))即可得到角速度-時間函數(shù),作圖,由速度=角速度*臂長可得車斗中心鉸接處線速度-時間圖二次求導(diff函數(shù))即可得到角加速度-時間函數(shù),作圖仿真圖像:圖14圖15圖16圖17圖18圖19圖20圖21總結(jié)課程設計已經(jīng)做完了,付出了很多,當然最后看到自己的團隊竟然做出了四十幾頁的文檔,真的不容易,覺得還是很有成就感的。經(jīng)過這次課程設計,我們學到了很多東西。對自卸車有了更多的了解。經(jīng)過查專利,我們學會了更快速的查找資料。經(jīng)過對現(xiàn)有機構的分析及運動鏈再生,我們加深了對課本知識的理解與運用。尺寸設計及運動仿真的過程,提高了我們的自學能力,使我們學會了使用inventor及matlab軟件對機構進行分析。鍛煉了我們的編程能力。這對我們以后解決實際問題很有幫助。做課程設計的過程中,我們也遇到了很多問題,有時還會感覺無從下手?？墒俏覀冏罱K都找到了解決的方法,克服了困難。課程設計也鍛煉了我們的耐心,畫圖與排版是個細活,必須耐心認真的去做。課程設計讓我們也學會了團隊間的分工與合作。只有配合好,才能做出好成果。最后感謝老師的指導,同學之間的幫助。小組分工情況:鐘志成:查找專利,運動鏈再生,畫機構簡圖,討論尺寸設計,inventor零件制作及動畫仿真,整理文檔,課程設計說明書高雙:現(xiàn)場拍照,查找專利,文獻綜述,畫機構簡圖,討論尺寸設計,matlab編程仿真,整理文檔,課程設計說明書索霄峰:查找專利,專利綜述,畫機構簡圖,討論尺寸設計,inventor零件制作及動畫仿真,整理文檔,課程設計說明書Reference[1]《機械JIXIE》,P72-73,《國產(chǎn)自卸汽車的液壓傾卸機構分析》;劉波,東風商用車公司重型車廠技術科;.20[2]《專用汽車》,P34-36,《改革開放三十年自卸車飛高走遠》;曲憲成,原青島專用汽車制造廠廠長;.01[3]《重型汽車》,P34-38,《談重型自卸車及其液壓傾卸機構的實例》;劉波;.02[4].com[5][6].com.hk[7]

附錄MATLAB程序代碼:(1)函數(shù)文件——Functions1.mfunctionf=functions1(p)globalsita;x=p(1);y=p(2);f(1)=2.4*cos(x)+0.5*cos(3.14-y)-0.8-1.8*cos(sita);f(2)=2.4*sin(x)-0.5*sin(3.14-y)-1.8*sin(sita);(2)單次升程——singlerise.mclear;clc;symsinitmovefinalinit=0.61;%初始液壓桿長move=0.03;%液壓桿伸縮速度3cm/sfinal=1.22;%終態(tài)液壓桿長globalsita;array1=[];%車斗角度數(shù)組array2=[];ganarray=[];%計算升程液壓桿長i=1.0;forgan=init:move:finalganarray(i)=gan;i=i+1;end%計算每一時刻角度——array1i=1.0;fortime=1:1:length(ganarray)gan=ganarray(time);yuxian=(0.528^2+0.8^2-gan^2)/(2*0.528*0.8);sita=24.62/180*pi+acos(yuxian)-pi/2;x=fsolve('functions1',[0.5,1.0]',optimset('Display','off'));x1=x(1);array1(i)=x1/pi*180;x2=x(2);array2(i)=x2/pi*180;i=i+1;endganlength=1:1:length(ganarray);nihe=polyfit(ganlength,array1,6);%對函數(shù)進行線性擬合,x=time,y=車斗角度fai=[];i=1.0;fortime=1:1:length(ganarray)gan=time;fai(i)=nihe(1)*gan^6+nihe(2)*gan^5+nihe(3)*gan^4+nihe(4)*gan^3+nihe(5)*gan^2+nihe(6)*gan+nihe(7);ifabs(fai(i)-array1(i))>5.0e-2%判斷擬合精度disp('擬合失敗!');endi=i+1;end%一階導數(shù)為角速度symsdegreeganx;degree=nihe(1)*ganx^6+nihe(2)*ganx^5+nihe(3)*ganx^4+nihe(4)*ganx^3+nihe(5)*ganx^2+nihe(6)*ganx+nihe(7);degree1=diff(degree,ganx);faiw=[];i=1.0;fortime=1:1:length(ganarray)gan=time;faiw(i)=subs(degree1,ganx,gan)/180*pi;i=i+1;end%二階導數(shù)為角加速度degree2=diff(degree1,ganx);faiacc=[];i=1.0;fortime=1:1:length(ganarray)gan=time;faiacc(i)=subs(degree2,ganx,gan)/180*pi;i=i+1;end%角速度*L1=速度faiv=[];i=1.0;fortime=1:1:length(ganarray)gan=time;faiv(i)=faiw(i)*2.4;i=i+1;end%作圖figure;plot(ganlength,fai);title('fai');figure;plot(ganlength,faiw);title('faiw');figure;plot(ganlength,faiacc);title('faiacc');figure;plot(ganlength,faiv);title('faiv');(3)全程——Fourier.mclear;clc;symsinitmovefinalinit=0.61;%初始液壓桿長move=0.03;%液壓桿伸縮速度3cm/sfinal=1.22;%終態(tài)液壓桿長pausetime=0;%停留時間globalsita;array1=[];%車斗角度數(shù)組array2=[];ganarray=[];%計算三程液壓桿長i=1.0;forgan=init:move:finalganarray(i)=gan;i=i+1;endforpause=1:1:pausetimeganarray(i)=gan;i=i+1;endforgan=final:-move:initganarray(i)=gan;i=i+1;end%計算每一時刻角度——array1i=1.0;fortime=1:1:length(ganarray)gan=ganarray(time);yuxian=(0.528^2+0.8^2-gan^2)/(2*0.528*0.8);sita=24.62/180*pi+acos(yuxian)-pi/2;x=fsolve('functions1',[0.5,1.0]',optimset('Display','off'));x1=x(1);array1(i)=x1/pi*180;x2=x(2);array2(i)=x2/pi*180;i=i+1;end%對函數(shù)進行傅立葉非線性擬合——利用cftool工具得到如下參數(shù),goodness=0.9994a0=25.03;a1=-24.74;b1=0.4654;a2=2.53;b2=-0.097;a3=-3.119;b3=0.1704;a4=0.7688;b4=-0.06069;a5=