SAETECHNICAL PAPERSERIES 961764 StudyofControlofTransmission and ClutchonOff-Highway Dumptruck K.Kishii,Y.Sato,Y.Ohkura,T.Murakami, andN.Hasegawa Komatsu Ltd. H.Ohnuki Komatsu America International Co. Reprinted from:Transmission andControls (SP-1191) International Off-Highway &Powerplant Congress &Exposition Indianapolis, Indiana August26-28,1996 400Commonwealth Drive,Warrendale, PA15096-0001 U.S.A.Tel:(412)776-4841 Fax:(412)776-5760 764Downloaded from SAE International by University of Auckland, Sunday, September 23, 2018Theappearance oftheISSNcodeatthebottomofthispageindicatesSAE'sconsent thatcopiesofthepapermaybemadeforpersonalorinternaluseofspecificclients. Thisconsentisgivenontheconditionhowever,thatthecopierpaya$7.00perarticle copyfeethroughtheCopyright Clearance Center,Inc.Operations Center,222 Rosewood Drive,Danvers, MA01923forcopyingbeyondthatpermitted bySections 107or108ofU.S.Copyright Law.Thisconsentdoesnotextendtootherkindsof copyingsuchascopyingforgeneraldistribution, foradvertising orpromotional purposes, forcreatingnewcollective works,orforresale. SAEroutinelystocksprintedpapersforaperiodofthreeyearsfollowingdateof publication. DirectyourorderstoSAECustomer SalesandSatisfaction Department. Quantityreprintratescanbeobtained fromtheCustomer SalesandSatisfaction Department. Torequestpermission toreprintatechnicalpaperorpermission tousecopyrighted SAEpublications inotherworks,contacttheSAEPublications Group. Nopartofthispublication maybereproduced inanyform,inanelectronic retrieval systemorotherwise, withoutthepriorwrittenpermission ofthepublisher. ISSN0148-7191 Copyright 1996SocietyofAutomotive Engineers, Inc. Positionsandopinionsadvanced inthispaperarethoseoftheauthor(s)andnot necessarily thoseofSAE.Theauthorissolelyresponsible forthecontentofthe paper.Aprocessisavailable bywhichdiscussions willbeprintedwiththepaperif itispublished inSAETransactions. Forpermission topublishthispaperinfullorin part,contacttheSAEPublications Group. Personswishingtosubmitpaperstobeconsidered forpresentation orpublication throughSAEshouldsendthemanuscript ora300wordabstractofaproposed manuscript to:Secretary, Engineering Meetings Board,SAE. PrintedinUSA 96-0049 Downloaded from SAE International by University of Auckland, Sunday, September 23, 2018961764 StudyofControlofTransmission and ClutchonOff-Highway Dumptruck K.Kishii,Y.Sato,Y.Ohkura, T.Murakami, andN.Hasegawa Komatsu Ltd. H.Ohnuki Komatsu America International Co. Copyright 1996SocietyofAutomotive Engineers, Inc. 1.Introduction Thisstudyhastwogoals.Oneistofindawayto reducethegearshiftingshocks (improveoperator comfort)ofoff-highway dumptrucks sothatoperators willnotbefatiguedeveniftheyoperatethevehiclefor manyhours,sinceitismainlyusedfortransportation ofmaterials between Point"A"andPoint"B".The otheristoreducethefuelconsumption (reducethe runningcost)oftheoff-highway dumptruck sinceits workistorunasefficiently andcheaplyaspossible. Toattainthegoalsoutlinedabove,westudied theimprovement ofthetorqueconverter and transmission byusingaloadsharingcontrolthat differsfromconventional electronic controls.2.Themeofstudy Thethemeandgoalofthisstudyareshownin Fig.1.Thisstudyhastwothemes.Oneistocontrol ofthelockupclutchoilpressure inthetorqueconverter toreducetheshocksmadewhenthegearisshifted andlowerthepeaktorque,andtheotheristocontrol transmission clutchoilpressuretoreducethethermal loadonthetransmission disc. Withthesecontrols, thepeaktorqueandthe thermal loadonthedisccanbelowered belowtheir currentlevelswithoutincreasing thesizeofthe transmission, eveniftheenginepowerisincreased (Inthisstudy,themaximum torqueoftheenginewas increased by30%andhorsepower by20%.) Accordingly, thesizeofthetransmission canbe reducedandfuelconsumption canbelowered. Downloaded from SAE International by University of Auckland, Sunday, September 23, 20183.Systemconfiguration Alarge-sized dumptruck whichhadbeen modifiedasshowninTable1andgiventhesystem showninFig.2wasusedforthisstudy. Downloaded from SAE Internati