TheEngineering Society ForAdvancing Mobility LandSeaAirandSpace® 400COMMONWEAL THDRIVEWARRENDALE, PA15096 381322 ACompuler=Amded Synthetical Method foraThreeDegreeoffreedom Multi= SpeedPlanetary Gearbox liuTailai NorthInstitute ofVehicle Beijing, People's Republic ofChina International Off-Highway &Powerplanl Congress andExposition Milwaukee. Wisconsin September 12-15.1988Downloaded from SAE International by University of New South Wales, Monday, September 17, 2018Theappearance ofthecodeatthebottomofthefirstpageofthispaperindicates SAE'sconsentthatcopiesofthepapermaybemadeforpersona! orinterntluse,or forthepersonal orinternaluseofspecificclients,Thisconsentisgivenonthecon~ dilion.however, thatthecopierpaythestatedperarticlecopyfeethrough the Copyright Clearance Cen,ter,Inc.,Operations Center,P.O.Box765,Schenectady, N.Y.12301,forcopyingbeyondthatpermitted bySections 107or108oftheU.S. Copyright Law.Thisconsentdoesnotextendtootherkindsofcopying suchas copying forgeneral distribution, foradvertising orpromotional purposes, for creating newcollective works,orforresale. Paperspublished priorto1978mayalsobecopiedataperpaperfeeof$2.50 undertheabovestatedconditions. SAEroutinely stocksprintedpapersforaperiodofthreeyearsfollowing dateof publication. DirectyourorderstoSAEOrdp.rDepartment. Toobtainquantityreprintrates,permission toreprintatechnical paperorper­ missionto'usecopyrighted SAEpublications inotherworks,contacttheSAE Publications Division. A11SAl:p;1pCrs11m ab.$lrl1Cled alldindexed In thOSAl:Giob<IJMoblitl'DatIJOO5f1 Nopartofthispublication maybereproduced inanyform,in anelectronic retrievalsystemorotherWise, withouttheprior writtenpermission ofthepublisher. ISSNOl48·7191 Copyright ©1988SocietyofAutomotive Engineers,lnc. Positions andopinions advanced inthispaperarethoseof theauthor(s) andnotnecessarily thoseofSAE.Theauthor Issolelyresponsible forthecontentofthepaper.Aprocess Isava1Jable bywhichdiscussions willbeprintedwiththe paperIfItIspublished InSAETransactions. Forpermission topublishthtspaperInfullorInpart,contacttheSAE Publications Division.Personswishingtosubmitpaperstobeconsidered for presentation orpUblication throughSAEshouldsendthe manuscriptora300wordabstract ofaproposed manus~ crlptto:Secretary, Engineering ActivityBoard.SAE. PrintedInU.S.A.Downloaded from SAE International by University of New South Wales, Monday, September 17, 2018881322 AComputer-Aided Synthetical Method foraThreeDegreeofFreedom Multi­ SpeedPlanetary Gearbox LiuTailai NorthInstitute ofVehicle Beijing,People's Republic ofChina ABSTRACT Amulti-function computer program vaecom­ posedwiththesynthetical methodbygraph.It contains asubprogram forjudging geomstrical contraditions inaplanetary gearbox Bcheme. Withthisprogram, alargenumberofreasonable schemesof2to4(even6)gearset planstary gearboxes withthreedegrees offreedom canbe automatically selectad fromallthepossible schemes. Itisveryconvenient touseittode­ signandanalyze amulti-speed planetary gear­ box. Inthispaper,themathematical models,the principles andtheflowcharts ofthisprogram andthesubprogram forjudging geometrical con­ tradictions arenarrated. Lastly, several examples oftheapplication oftheprogram arecited. Wecanobtainmany reasonable schemes fromwhichtheoptimum one maybeselected. THEPURPOSE OFTHISPAPERistointroduce acom­ puterprogram solution todesignoptimum schemes foramulti-speed planstary gearbox withthree degrees offreedom. Aplanetary gearbox withthreedegreesof freedom (3PG)basalotofattraotive advantsges thatfindnumerous applications ondifferent au­ tomobiles. Thedesignofa3PGmustmeetnumer­ ousrequirements suchasgearratios, basicra­ tiosk,loyrotational speeds, momenta ofcon­ trolelements, highefficiency, compaot andsim­ pleconstruction, changespeedsandsoon.The numberofitspossible schemesisverygraatand theoptimum sohemeisdifficult todesign.Itis necessary tosetupascientific andpractical synthetical methodfordesigning anew3PG. Somepapersdiscuss the3PGproblem with3 simpleplanetary gearsets (