Toro Reelmaster 3100-D Service Manual

TractionCircuits
Thetractioncircuitofthehydraulicsystemconsistsofahydrostatconnectedina
closedloopcircuittothreeorbitalvanewheelmotors.
Themow/transportslidecontrolonthemachineshaspositionsformowand
transport.Themowpositionallowstractionpedalinputsthatareappropriatefor
mowspeedsbylimitingthemovementofthetractionpedalandthepistonpump
swashplate.Thetransportpositionallowsfullmovementofthetractionpedalso
completepumpswashrotationispossible.
Forward
Theenginedrivestractionpump(P3)indirectlythroughpulleysandaV−belt.
Thetractionpumpisavariabledisplacementpistonpump.Thetractionpedal
connectsthroughacabletothetrunnionshaftandswashplateofthepump.With
theenginerunningandthetractionpedalintheneutralposition,P3suppliesno
owtothewheelmotors.Whenthetractionpedalispressedtotheforward
position,thecablefromthepedalpositionstheswashplateinthetractionpump
souidowsoutofthelowerport.Fluidowoutofthelowerportgoestothe
wheelmotorsandturnsthemintheforwarddirection.Fluidowingoutofthe
wheelmotorsreturnstoupperportofthehydrostatandiscontinuouslypumped
outofthelowerport.
Operatingpressureintheclosedtractioncircuitisdeterminedbytheamountof
loaddevelopedbythewheelmotors.Astheloadincreases,circuitpressurecan
increasetothereliefvalvesettingof241.3bar(3500PSI).Inforwardoperation,
uidowsthroughtheinternalhydrostatreliefvalvetothelowpressuresideof
thetractioncircuitwhencircuitpressureexceedsthereliefsetting.
Reverse
Thetractioncircuitoperatesessentiallythesameinreverseasitdoesinforward.
However,thereareafewdifferencesinoperation.
Whenthereversetractionpedalisdepressed,thecablefromthepedalpositions
theswashplateinthetractionpumpsouidowsoutoftheupperport.Fluid
owoutoftheupperportgoestothewheelmotorsandturnstheminthereverse
direction.Fluidowingoutofthewheelmotorsreturnstothelowerportofthe
hydrostatandiscontinuouslypumpedoutoftheupperport.Fluidby−passesthe
rearmotorinreversebecauseofthecheckvalveinsidetherearmotor.
ChargeCircuit
Thetractionpumpusesasmallamountofhydraulicuidforinternallubrication.
Fluidisdesignedtoleakacrosspumppartsintothecasedrain.Thisleakage
resultsinthelossofhydraulicuidfromtheclosedloopcircuitthatmustbe
replenished.
Thegearpump(P2)isdirectlycoupledtothehydrostatthroughgearpump
(P1)anddrivenbytheengine.Gearpump(P2)supplieshydraulicpressurefor
operatingthepowersteeringsystem,raisingandloweringthecuttingunits,
andoperatingthesidewinderunit.Gearpump(P2)mayalsobereferredtoas
thechargepumpasowfromthegearpumpalsoreplenishestheclosedloop
tractioncircuit.Hydraulicuidexitsthelift/sidewindervalve,passesthroughthe
mowmanifoldandcontinuesontothehydrostat.Areliefvalvelocatedinthe
hydrostatprovidessufcientresistancesothatowisguidedtothelowpressure
sideofthetractioncircuitthroughoneoftwocheckvalves(chargecircuit).Pump
owinexcessof6.9to10.3bar(100to150PSI)isrelievedthroughtherelief
valvebacktothegearpumpinletandhydraulictank.
Reelmaster
®
3100-D/3105-D
Page5–15
HydraulicSystem:HydraulicFlowDiagrams
20252SLRevA

Toro Reelmaster 3100-D Specifications

General

Brand	Toro
Model	Reelmaster 3100-D
Category	Lawn Mower
Language	English