




已閱讀5頁,還剩9頁未讀, 繼續(xù)免費閱讀
版權說明:本文檔由用戶提供并上傳,收益歸屬內容提供方,若內容存在侵權,請進行舉報或認領
文檔簡介
ScienceinChinaSeriesE:TechnologicalSciences2007ScienceinChinaPressSpringer-VerlagStudyofutilizingdifferentialgeartraintoachievehybridmechanismofmechanicalpressHEYuPeng1,ZHAOShengDun2,ZOUJun2&ZHANGZhiYuan21SchoolofMechanicalEngineering,NanjingUniversityofScience&Technology,Nanjing210094,China;2SchoolofMechanicalEngineering,XianJiaotongUniversity,Xian710049,ChinaTheproblemsofhybridinputofmechanicalpressarestudiedinthispaper,withdifferentialgeartrainastransmissionmechanism.Itisproposedthat“adjustable-speedamplitude”or“differential-speedratio”istheimportantparametersforthehybridinputmechanism.Itnotonlydefinestheamplitudeoftheadjustablespeed,butalsodeterminestheratioofthepoweroftheservomotortothepoweroftheconventionalmotor.Thecalculatingequationsoftheratiooftransmissioninallaxes,thepoweroftwomotors,andtheworkingloaddistributionarededuced.Thetwokindsofdrivingschemesareputforwardthattheservomotorandtheconventionalmotorsimultaneouslydriveandtheservomotorandtheconventionalmotorseparatelydrive.Thecalculatingresultsdemonstratethatthelatterschemecanusemuchlowerpoweroftheservomotor,sothisschememakesmanufactureandusecostmuchlower.Thelatterschemeproposesafeasiblewaytoapplythehybridmechanismofmechanicalpressinpracticeengineering.mechanicalpress,hybridmechanism,differentialgeartrain,adjustable-speed1IntroductionAtpresenttherearemanyresearchpapersaboutthehybridmechanismofmechanicalpress,andithasbecomeahotresearchtopic.Thehybridmechanismisamechanismwith2-degree-offreedom(alsocalleddifferentialspeedmechanism),andwhentwoindependentmotionsareinputatthesametime,theoutputthatcansatisfysomemotionrequirementsisobtainedthroughthemotioncompositionofthemechanism.Thehybridmechanismisalsocalledcontrollablemechanism,orhybridmachine.Thepurposeofresearchonhybridmechanismofmechanicalpressisusingconventionalmotorwithbigpowercarryingflywheeltofinishstampingworkpieces;andusesservomotorwithlowpowertoadjustthesliderspeed.Theadvantagesofthehybridmechanismappliedinthemechanicalpressarethatitnotonlycanreducemuchlowermanufacturingcostthanservopress,butalsohasaflexibleworkingvelocityofslider1.Sothemechanicalpressofhybridmechanismarousesmanyresearchersinterestinworkingonit;andthesestudiesaremainlyfocusedonthemulti-barhybridmechanism.DuandGuo1,2havecomprehensivelydiscussedtheseven-barhybridmechanismofmechanicalpress,includingthefeasibleconditionsofcompositionofthelinkagemechanism,theslidermotionanalysis,andthetorqueandpowerdistributionbetweenthetwomotorsaswellastheoptimaldesign.Thetrajectoryplanningbasedonpolynomialinterpolationisalsoinvestigated,andthecomputersimulationshowsthattheresultisindeedattractive.Inaddition,Meng3hasalsoinvestigatedthekinematicalanalysisoftheseven-barmechanism,andtheoptimaldesignhasbeencompletedbasedontheminimumpoweroftheservomotormotor,andMenghasproposedthatthehybridmechanismisaresearchdirectionofthemechanicalpress.Tokuz4firstputforwardofthehybridmechanismandanalyzedthevelocitysynthesisbyusingthedifferentialgeartrain.Hisexperimentconfirmedthefeasibilityofhisconception.Theconceptsoftheadjustable-speedamplitudeanddifferential-speedratioarenotmentionedintheirworks,andtherelationshipbetweenthevelocityvariationandthepowerofthetwomotorswerenotclearlygiven58.Buttheseconceptsareveryimportantandabsolutelynecessaryforthehybridmechanismtoselectthetwomotorspoweranddeterminetheworkingloaddistributionbetweenconventionalmotorandtheservomotor.Inrefs.13theyusedlinkagemechanismtoimplementthehybridinputofmechanicalpress.Themethodisverycomplexbecausethechangeofthelengthandpositionoftheeachbarinlinkagemechanismwillhaveaneffectonthemotionoftheslideofthemechanicalpress.Sosomeprincipalproblemsareusuallyignoredinresearchhybridmechanismcourse,andtheresearchresultsdonnotalwayscoincidewiththepracticeengineeringconditions911.Thegeardifferentialtrainhastwofreedoms,andtheratiosoftransmissionbetweenarbitrarytwoaxesareaconstant.Inordertosimplifythemechanicalmodelandmaketheproblemsmuchprojected,thedifferentialgeartrainisusedastransmissionmechanismtostudythehybridproblemsofthemechanicalpressinthispaper.Thispaperaddressestherelationshipbetweentheadjustable-speedamplitudeandthepowerofthetwomotors,theworkingloaddistributionbetweenthetwomotors,andputsforwardtwodriveschemesoftheconventionalmotorandtheservomotorsimultaneouslyworking,andtwomotorsseparatelyworking.Withthe200-tonmechanicalpressastheengineeringbackground,adrivesystemofthehybridmechanismofthemechanicalpressisdesigned,andthefeasibilityofthetwodriveschemesinmechanicalpressisanalyzed.2TheprincipleofthehybridmechanismTheworkingprincipleofthehybridmechanismofthemechanicalpresswithdifferentialgeartrainisillustratedinFigure1.Thesystemconsistsofconventionalmotor(alsocalledACmachinewithconstantspeed),servomotor,reducingunitI,reducingunitII,differentialgeartrain,andcrankslidemechanism.Theoutputaxisofthedifferentialgeartrainisconnectedwiththecrankshaftofthecrankslidemechanism.Oneofthetwoinputaxeslinkstheconventionalmotorthroughthereducingunit;theotherinputaxislinkstheservomotorthroughthereducingunitII.Thereforethemotionofthecrankshaftiscompletelycontrolledbythemotionsoftheconventionalmotorandtheservomotor.ThereducingunitandthereducingunitIIarerespectivelyinstalledbetweenthetwomotorsandthedifferentialgearunitinthewayofserialinordertobearapartofreducingvelocitytaskofthealltransmissionsystem,becausetoobigdriveratioofthedifferentialgeartrainwillmakeitsdrivingefficiencydecreased.Theangularvelocityoftheconventionalmotorisconstant,soitspriceischeaper.Theangularvelocityoftheservomotorisadjustable,soitspriceisexpensive.Inthesystemofthehybridmechanismtheconstantspeedoftheoutputaxisisprovidedbyhighpowerconventionalmotor;andtheservomotorprovidesitsadjustablespeed.Therefore,inthisway,itnotonlymakestheoutputmotionofthecrankshaftofthemechanicalpressflexible,butalsoavoidsusinghighpowerservomotor.Henceitcouldsaveboththemachinemanufacturingcostsandthemachineoperatingcosts.Figure1Workingprincipleofhybridmechanismofdifferentialgeartrain.3ThevelocitycharacteristicsofthemechanicalpressslideTheworkofthemechanicalpresspresentstheregularityoftheperiodicchange12.ThedisplacementandvelocitychangesofthemechanicalpressslideinanidealworkcirculationareillustratedintheFigure2.Theslidestartstomovefromtopdeadcentertotheworkingstartpointathighvelocity(calledquickfeedingstage).Whentheslideofmechanicalpressapproachestheworkingpoint,itshighvelocityisshiftedtoslowvelocityandthenitbeginstostampworkpieceatlowvelocity(calledlowworkingstage).Thelowvelocityoftheslideistoavoidgreatimpactonthedie,andbenefittheplasticshapingoftheworkpiece.Aftertheslidefinishesthestampingworkandreachesthebottomdeadcenter,theslidecomesbackathighvelocityandstopsatthetopdeadcenter(calledquickbackstage).Hence,themotionvelocityofthemechanicalpressslidecanbedividedthreekinds:highdownvelocityV1,slowworkingvelocityV2,andhighbackvelocityV3.ThevelocityV1andvelocityV3shouldbeaspossibleashighandthevelocityV2shouldbeslowandflexibleinordertoensurehighworkingtimesofthemechanicalpressperminuteandsatisfytherequirementsofdifferenttechnologies.Actuallythemechanicalpressonlyworksinaveryshortcoursebeforethebottomdeadcenter,andintheothercoursesitdoesnotdoworktotheworkpiece.4Thenomenclaturesandequationsofthehybridmechanism4.1TherelationshipoftheangularvelocityinallaxesTherearethreeexternalaxesinthedifferentialgeartrainasillustratedinFigure1.Inordertoconvenientlyexpresstherelationshipofthethreeaxes,theaxisconnectedwiththeconventionalmotoriscalledaxis1,theaxisconnectedwithservomotoriscalledaxis2,andtheaxisconnectedwithcrankshaftiscalledaxis0.Theangularvelocitiesofthethreeaxesarerespectivelyexpressedasn1,n2andn0.ThetorquesofthethreeaxesarerespectivelyexpressedasM1,M2andM0.Becausetherearetwofreedomsinthedifferentialgeartrain,onlythethirdaxisisfixed,suchthatthedriveratiooftheothertwoaxescanbedetermined.Sotherelationshipsofdriveratioandangularvelocityofthethreeaxesneedtobeexpressedasthecharacterwithsuperscriptandsubscript.Figure2Idealdisplacementcureoftheslide.4.1.1Theconventionalmotorsinfluenceontheoutputmotion.Whentheservomotorstops,n2=0,onlytheangularvelocityoftheconventionalmotoraffectstheoutputangularvelocitynTheservomotorsinfluenceontheoutputmotion.Whentheconventionalmotorstops,n1=0,onlytheangularvelocityoftheservomotoraffectstheoutputangularvelocityn0,where1n0representsaxis0angularvelocity,and1i20representstotaldriveratiofromaxis2toaxis0includingdifferentialgeartrainandreducingunitIIwhenaxis1(servomotoraxis)isfixed.4.1.3Theconventionalmotorsandservomotorsinfluenceontheoutputmotion.Whentheconventionalmotorandtheservomotorrunatthesametimethroughthecompositionofthedifferentialgeartrain,theoutputvelocitycanbeexpressedas.Becausetheservomotorcanrunatarbitraryangularvelocitybetweenthezeroandspecificvelocityinbothpositiveandnegativedirections,n2canbeexpressedas.whereKistheratiooftheactualangularvelocitytothespecificangula
溫馨提示
- 1. 本站所有資源如無特殊說明,都需要本地電腦安裝OFFICE2007和PDF閱讀器。圖紙軟件為CAD,CAXA,PROE,UG,SolidWorks等.壓縮文件請下載最新的WinRAR軟件解壓。
- 2. 本站的文檔不包含任何第三方提供的附件圖紙等,如果需要附件,請聯(lián)系上傳者。文件的所有權益歸上傳用戶所有。
- 3. 本站RAR壓縮包中若帶圖紙,網(wǎng)頁內容里面會有圖紙預覽,若沒有圖紙預覽就沒有圖紙。
- 4. 未經(jīng)權益所有人同意不得將文件中的內容挪作商業(yè)或盈利用途。
- 5. 人人文庫網(wǎng)僅提供信息存儲空間,僅對用戶上傳內容的表現(xiàn)方式做保護處理,對用戶上傳分享的文檔內容本身不做任何修改或編輯,并不能對任何下載內容負責。
- 6. 下載文件中如有侵權或不適當內容,請與我們聯(lián)系,我們立即糾正。
- 7. 本站不保證下載資源的準確性、安全性和完整性, 同時也不承擔用戶因使用這些下載資源對自己和他人造成任何形式的傷害或損失。
最新文檔
- 2025年懸浮床加氫裂化催化劑項目建議書
- 幼兒行為觀察記錄培訓
- 護理反思日記實踐體系
- 社區(qū)護理評估方法
- 經(jīng)濟適用房滿年限上市買賣及共有權證明注銷合同
- 影視行業(yè)服裝道具損壞賠償補充合同
- 醫(yī)療機構護理勞務外包保密協(xié)議書
- 能源行業(yè)市場調研與分析補充協(xié)議
- 直播帶貨平臺與商家傭金分成協(xié)議
- 豪華私人飛機氧氣艙設施租賃服務協(xié)議
- 山東省青島市嶗山區(qū)2024-2025學年初三下學年期末考試英語試題試卷含答案
- 溫州市普通高中2025屆高三第三次適應性考試化學試題及答案
- 學校運動場改造方案與實施指南
- 2025年北京市東城區(qū)九年級初三一模語文試卷(含答案)
- 遼寧省名校聯(lián)盟2023-2024學年高一下學期6月聯(lián)合考試化學試題(解析版)
- 2025屆云南省昆明市高三下學期“三診一?!钡谌谓y(tǒng)測(4.28)作文學案
- 防火墻技術及應用(教學)
- 2025年蚌埠市龍子湖區(qū)產(chǎn)業(yè)發(fā)展有限公司招聘22人筆試參考題庫附帶答案詳解
- 2025華晉焦煤井下操作技能人員招聘100人(山西)筆試參考題庫附帶答案詳解
- 2024年中國工程院戰(zhàn)略咨詢中心勞動人員招聘筆試真題
- 江蘇省蘇州市2025年高考仿真卷英語試卷含解析
評論
0/150
提交評論