BRANCH AUTOMOBILE ENGINEERING
SEM 5TH
SUBJECT AUTOMOTIVE SYSTEM
CHAPTER 03
TOPIC PROPELLER SHAFT
FACULTY Er. BALADHARA JENA
Introduction of Propeller Shaft
⮚Propellershaftisconnectingthedrivefromgearboxtofinal
drive.HenceitisalsocalledDriveShaft.
OR
⮚Itisthegroupofpartsconnectingthetransmissionwiththe
drivewheels.Itconsistsofpropellershaft(alsocalledDrive
Shaft),UniversalJoints/ConstantVelocityJointsandSlip
Joints.
Introduction of Propeller Shaft
⮚Shaft:Asthishastowithstandtorsionalloads,itisusuallymadeof
tubularcross-section.Italsohastobewellbalancedtoavoidwhirlingat
highspeeds.Shaftsaremadeofsteel,aluminumorcompositematerials.
⮚UniversalJoint:Oneortwouniversaljoints,dependinguponthetype
ofrearaxledriveused.Theuniversaljointsaccountfortheupand
downmovementsoftherearaxlewhenthevehicleisrunning.
⮚SlipJoint:Dependinguponthetypeofdrive,oneslipjointmaybe
thereinshaft.Thisservestoadjustthelengthofthepropellershaft
whendemandedbyrearaxlemovements.
Introduction of Propeller Shaft
Introduction of Propeller Shaft
More about Propeller Shaft
⮚Thepropellershaftisusedasadrivingshafttojointtheoutputshaftof
thegearboxwiththedifferentialunitintherearaxle.
⮚Therotationalmotionofthegearboxmainshaftistransferredtothe
differentialunitforrotatingthedrivewheelsmainlytorsionalloadacts
onthepropellershaft,henceitismadeoftubularcross-section.
⮚Topreventtheturbulencegenerationathighspeed,itisperfectly
balance.
⮚Universaljointisprovidetotransmitthepoweratchanginganglesof
thepropellershaft,whilevehicleisrunning.
⮚Slipjointisprovidedwiththepropellershaft,totakecareofincreasein
lengthofpropellershaft,whilevehicleisrunning.
Function of Propeller Shaft
⮚Propellershafttakepowerfromthegearboxoutputshaftwithout
makinganychangeinpower,ittransmitsthesametotheinputpinionof
thedifferentialunit,fromwherepoweristransmittedtothedrive
wheelsthroughrearaxle.
⮚Toaccommodatethechangeinlineandlevelbetweengear-boxoutput
shaftanddifferentialinputpinionshaft.
Constructional details of Propeller Shaft
⮚Thepropellershaftusedtotransmitthepowerfromgearboxoutput
shafttodifferentialwithtubularcross-section&oneortwopiece
construction.
⮚Thetwopiecepropellershaftissupportedatthecenterbyrubber
mountedbearing.
⮚Propellershaftshouldberigidenoughtoabsorbthetwistingactiondue
todrivingtorqueandthetorsionalshock.
⮚Itshouldalsobecapableofresistingthevibration.
Constructional details of Propeller Shaft
⮚Tubularpropellershaftisgenerallyusedbecause...
⮚Itweightless
⮚Itcanresistmisalignment
⮚Ithasgoodtorsionalstrength
⮚Itprovidelessresistancetochangeofangularspeedcausedwhenhooktype
couplingisused.
⮚Propellershaftisrunningfasterwhenoverdriveisused,henceitshould
beproduceasperrequireddesignspecificationandgoodlimitof
balances.
Vibration of Propeller Shaft
⮚Thevehiclehavingbiggerwheelbaseneedlongpropellershaft.Long
propellershaftgeneratedwhirlingbybendingatitscenter.
⮚Insuchconditionresonantvibrationsareproducedinthebody.Hence
alongwiththewhirls,vehiclebodyalsovibrates.
⮚Forresonantfrequencyofpropellershafttherearetwogroupsofmain
factorsproducingvibration.
⮚FactorsrelatedtoPropellerShaft
⮚FactorsrelatedtoVehicleBody
Vibration of Propeller Shaft
⮚FactorsrelatedtoPropellerShaft
⮚ShaftDiameterandLength
⮚BalancingofassembledshaftandJoints
⮚BendingresistanceoftheShaft
⮚FactorsrelatedtoVehicleBody
⮚Shapeandtypeofbodystructure
⮚Locationofbodystructureparts
⮚Enginetransmissionmountings,springs,bushingandpenal
insulationbyclampingqualityfordriveshaftvibration
Vibration of Propeller Shaft
⮚Shiftingofcenterofgravityisalsoresponsibleforvibration.
⮚Bendingofshaftatcenter
⮚Irregularthicknessofwallofshafttube
⮚Byrollingfromflatsheettheshaftisproducedfinallybywelding.
Theweldedportionmaynothaveweightsameasthatofopposite
metal
⮚Thejointsofyokeandtrunnionsareatonesideofaxis
⮚Theclearanceofsplinesshaftisallowingshafttoshifttowardsone
side
Torque Tube Drive
Torque Tube Drive
⮚Intorquedrive,thepropellershaftisenclosedinahollowtube.
⮚Thetubeisrigidlyboltedtothedifferentialhousingatoneendandis
fastenedattheotherendtothetransmissionthroughasomewhat
flexiblejoint(universaljoint)situatedinsphericalcupfixedtothe
frame.
⮚Thetorquereactionanddrivingthrustaretakenupbytorquetube.
⮚Whenthevehiclecomesacrossabumporshocks,thecentrelineofthe
bevelpinionshaftwillnotbeshiftandalwayspassesthroughthecentre
ofsphericalcup.
Torque Tube Drive
⮚Hence,onlyoneuniversaljointisrequiredatfrontendandnouniversal
jointattherearend.
⮚Thetubeincorporatesbearing,whichsupportthepropellershaft.
⮚Itisusuallylocatedbetweenthe(transmission)gearboxandthe
propellershaft.
⮚Noslidingjointisrequiredinthepropellershaft.
⮚Inthisdrive,theleafspringstakesonlythesidethrustbesides
supportingweightofthebody.
Hotchkiss Drive
Hotchkiss Drive
⮚TheHotchkissdriveissimplestandmostpopularformofrearaxlesuspension.
⮚Hotchkissdrivecombinesthespringingandpositioningorlocatingoftherear
axle.Itusesarigidaxlewithleafspringmountedatitsextremitiesasfarapartas
possibleontherearaxle.
⮚TheHotchkissdriveconsistsofaleafspringandapropellershaftwithtwo
universaljointsandoneslidingjoint.
⮚Thefrontendoftheleafspringispivotedinpinofbracketwhichisboltedtothe
vehicleframe.
⮚Whilerearendoftheleafspringissupportedinswingingshacklewith
antifrictionbushmaterial.
⮚Theleafspringsareboltedrigidlytotherearaxlecasingatmiddle.
⮚Thespringtakesweightofbody,torquereactionanddrivingthrust.
Hotchkiss Drive
⮚Thedrivingandbrakingtorquesareabsorbedthroughthefronthalfoftherear
leafspringshownbydottedline.
⮚Duringdrivingandbraking,thebevelpinionchangesthepositionsothelength
andangleofpropellershaftchangeswhichwillbeadjustedbyuniversaljointand
slidingjoint.Thereforeifonlyoneuniversaljointisatthefrontend,thenthe
propellershaftmaybendordamage.
⮚Toavoidthis,anotheruniversaljointisprovidedatrearend.
⮚Whenthevehiclecomesacrossabumporshocks,therearaxlemovesupand
downandithastomoveinacirclewithfrontspringsupportedattheframeas
centre.
⮚Duringthismovementofrearaxle,thelengthofthepropellershaftchanges
whichwillbeadjustedbyslidingjoint.
Universal Joint
⮚Auniversaljointallowsdrivingtorquetobecarriedthroughtwoshaftsthatareat
ananglewitheachother.
⮚AsimpleuniversaljointconsisttwoY-shapedyoke,oneonthedrivingshaftand
otheronthedrivenshaft.
⮚Thefourarmsofspiderareassembledinneedlebearingsinthetwoyokes.The
drivingshaftandyokeforcethespidertorotate.
⮚Theothertwotrunnionsofthespiderthencausethedrivenyoketorotate.
⮚Whenthetwoshaftsareatananglewitheachother,theneedlebearingspermit
theyokestoswingaroundonthetrunnionswitheachrevolution.
Universal Joint
⮚Asimpleuniversaljoint
doesnottransmitthemotion
uniformlywhentheshafts
areoperatinganangle.
Becauseof this, two
universaljointsareusedina
vehicle,onebetweenthe
gearboxandthepropeller
shaftandotherbetweenthe
propellershaftand the
differentialpinionshaft.
Constant Velocity Joint
⮚Constant-velocityjoints(akahomokineticorCVjoints)allowadriveshaftto
transmitpowerthroughavariableangle,atconstantrotationalspeed,withoutan
appreciableincreaseinfrictionorplay.
⮚TheyaremainlyusedinfrontwheeldriveandmanymodernRearwheeldrive
carswithindependentrearsuspensiontypicallyuseCVjointsattheendsofthe
rearaxlehalfshafts,andincreasinglyusethemonthepropshafts.
⮚Constant-velocityjointsareprotectedbyarubberboot,aCVgaiter.Cracksand
splitsinthebootwillallowcontaminantsin,whichwouldcausethejointtowear
quickly.
Constant Velocity Joint
Slip Joint
⮚Slipjointisattachedtothedrivenyokeinordertheincreaseor
decreasethelengthofpropellershaft.
⮚Ithasoutsidesplinesontheshaftandmatchinginternalsplinesina
matinghollowshaftoryoke.
⮚Whenassembledthesplinescausetheshaftstorotatetogetherwhile
theycanmovebackandforth.Thischangesthelengthofpropeller
shaft.
Slip Joint