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Themachinerysteeringsystemisrefersbypilot'
sphysicalstrengthachievementchangestheenergy,inwhichallpowertransmissionallismechanical,theautomobilechangesthemovementisoperatesthesteeringwheelbythepilot,transmitsthroughthediverterandaseriesofmemberschangesthewheeltorealize.Themechanicalsteeringsystembychangesthecontrolmechanism,thediverterandmajorpartchangesthegearing3tobecomposed.
Usuallymaydivideintoaccordingtothemechanicaldiverterform:
Thegearracktype,followsroundtheworld-like,thewormhearingadjusterhooptype,thewormbearingadjusterreferssellsthetype.Isthegearracktypeandfollowsusingthebroadesttwokindsroundtheworld-like(usesinneedingtimebigsteeringforce).Infollowsroundtheworld-likeinthediverter,theinputchangesthecircleandtheoutputsteeringarmpivotangleisproportional;
Inthegearracktypediverter,theinputchangestheturnandtheoutputrackdisplacementisproportional.Followsroundtheworld-likethediverterbecauseistherollingfrictionform,thusthetransmissionefficiencyisveryhigh,theeaseofoperationalsotheservicelifearelong,moreoverbearingcapacity,thereforewidelyappliesonthetruck.Thegearracktypediverterwithfollowsroundtheworld-likecompares,themostmajorcharacteristicistherigidityisbig,thestructurecompactweightislight,andalsothecostislow.Becausethiswaypassesoneasilybythewheelthereactingforcetothesteeringwheel,thereforehastothepavementbehaviorresponsekeenmerit,butsimultaneouslyalsoeasytohavephenomenaandsoongoonandoscillation,alsoitsloadhearingefficiencyrelativeweak,thereforemainlyappliesonthecompactcarandthepickuptruck,atpresentthemajorityoflowendpassengervehicleusesisthegearracktypemachinerysteeringsystem.
Alongwiththevehiclescarryingcapacityincreaseaswellasthepeopletothevehicleshandlingqualityrequestenhancement,thesimplemechanicaltypesteeringsystemwerealreadyunabletomeettheneeds,thepowersteeringsystemariseatthehistoricmoment,itcouldrotatethesteeringwheelwhilethepilottoprovidetheboost,thepowersteeringsystemdividesintothehydraulicpressuresteeringsystemandtheelectricallyoperatedsteeringsystem2kinds.Hydraulicpressuresteeringsystemisatpresentusesthemostwidespreadsteeringsystem.
Thehydraulicpressuresteeringsystemincreasedthehydraulicsysteminthemechanicalsystemfoundation,includinghydraulicpump,Vshapehandpulley,drilltubing,feedinstallment,boostinstallmentandcontrolvalve.Itwiththeaidofinthemotorcarenginepoweractuationhydraulicpump,theaircompressorandthegeneratorandsoon,bythefluidstrength,thephysicalstrengthortheelectricpowerincreasesthepilottooperatethestrengthwhichthefrontwheelchanges,enablesthepilottobepossiblenimblytooperatemotorturningfacilely,reducedthelaborintensity,enhancedthetravelsecurity.
Thehydraulicpressurebooststeeringsystemfrominventedalreadyhadabouthalfcenturyhistorytothepresent,mightsaywasonekindofmoreperfectsystem,becauseitsworkreliable,thetechnologymaturestillwidelyisapplieduntilnow.Ittakesthepowersupplybythehydraulicpump,afteroilpipe-linecontrolvalvestopowerhydrauliccylinderfeed,throughtheconnectingrodimpetusrotationgearmovement,maychangestheboostthroughthechangecylinderboreandtheflowingtubingheadpressuresizethesize,fromthisachievedchangestheboostthefunction.Thetraditionalhydraulicpressuretypepowersteeringsystemmaydivideintogenerallyaccordingtotheliquidflowform:
Ordinaryflowtypeandatmosphericpressuretype2kindoftypes,alsomaydivideintoaccordingtothecontrolvalveformtransfersthevalvetypeandtheslide-valvetype.
Alongwithhydraulicpressurepowersteeringsystemonautomobiledailypopularization,thepeopletooperateswhentheportabilityandtheroadfeelingrequestalsodaybydayenhance,howeverthehydraulicpressurepowersteeringsystemhasmanyshortcomingsactually:
1Becauseitsitselfstructurehaddecideditisunabletoguaranteevehiclesrotatesthesteeringwheelwhenanyoperatingmode,allhastheidealoperationstability,namelyisunablesimultaneouslytoguaranteetimethelowspeedchangestheportabilityandthehighspeedtimeoperationstability;
2Theautomobilechangesthecharacteristictodrivethepilottechnicaltheinfluencetobeserious;
3thesteeringratioisfixed,causesthemotorturningresponsecharacteristicalongwithchangesandsoonvehiclespeed,transverseaccelerationtochange,thepilotmustaimatthemotorturningcharacteristicpeak-to-peakvalueandthephasechangeaheadoftimecarriesoncertainoperationcompensation,thuscontrolstheautomobileaccordingtoitswishtravel.Likethisincreasedpilot’soperationburden,alsocausesinthemotorturningtravelnottohavethesecurityhiddendanger;
Buthereafterappearedtheelectricallycontrolhydraulicboostersystem,itincreasesthevelocitygeneratorinthetraditionalhydraulicpressurepowersteeringsystemfoundation,enablestheautomobilealongwiththevehiclespeedchangeautomaticcontrolforcesize,hastoacertainextentrelaxedthetraditionalhydraulicpressuresteeringsystemexistencequestion.
Atpresentourcountryproducesonthecommercialvehicleandthepassengervehicleusesmostlyistheelectricallycontrolledhydraulicpressurebooststeeringsystem,itisquitematureandtheapplicationwidespreadsteeringsystem.Althoughtheelectricallycontrolledhydraulicservoalleviatedthetraditionalhydraulicpressurefromcertaindegreetochangebetweentheportabilityandtheroadfeelingcontradiction,howeveritdidnothavefundamentallytosolvetheHPSsystemexistenceinsufficiency,alongwithautomobilemicroelectronictechnologydevelopment,automobilefueloilenergyconservationrequestaswellasglobalinitiativeenvironmentalprotection,itinaspectandsoonarrangement,installment,leak-proofquality,controlsensitivity,energyconsumption,attritionandnoiseinsufficienciesalreadymoreandmoreobvious,thesteeringsystemturnedtowardstheelectricallyoperatedbooststeeringsystemdevelopment.
Theelectricallyoperatedbooststeeringsystemisthepresentmotorturningsystemdevelopmentdirection,itsprincipleofworkis:
HPSsystemKCUaftercomesfromthesteeringwheeltorquesensorandthevehiclespeedsensorsignalcarriesonanalysisprocessing,controlstheelectricalmachinerytohavethesuitableboosttorque,assiststhepilottocompletechangestheoperation.Inthelastfewyears,alongwiththeelectronictechnologydevelopment,reducesEPSthecosttobecomelargescalepossibly,Japansendsthecarcompany,MitsubishiCarcompany,thisfieldcarcompany,US'
sDelphiautomobilesystemcompany,TRWCorporationandGermany'
sZFCorporationgreatlyalloneafteranotherdevelopsEPS.Mercedes2BcnzSiemensAutomotiveTwobigcompaniesinvested65,000,000poundstouseindevelopingEPS,thegoalaretogetherloadacarto2002,yearlyproduce300tenthousandsets,becametheglobalEPSmanufacturer.Sofar,theEPSsystemintheslightpassengervehicle,onthetheaterboxtypevehicleobtains(hiswidespreadapplication,andeveryyearby300tenthousandspeeddevelopment.
Steeringisthetermappliedtothecollectionofcomponents,linkages,etc.whichallowforavessel(ship,boat)orvehicle(car)tofollowthedesiredcourse.Anexceptionisthecaseofrailtransportbywhichrailtrackscombinedtogetherwithrailroadswitchesprovidethesteeringfunction.
Themostconventionalsteeringarrangementistoturnthefrontwheelsusingahand-operatedsteeringwheelwhichispositionedinfrontofthedriver,viathesteeringcolumn,whichmaycontainuniversaljointstoallowittodeviatesomewhatfromastraightline.Otherarrangementsaresometimesfoundondifferenttypesofvehicles,forexample,atillerorrear-wheelsteering.Trackedvehiclessuchastanksusuallyemploydifferentialsteering—thatisthetracksaremadetomoveatdifferentspeedsoreveninoppositedirectionstobringaboutachangeofcourse.
Manymodemcarsuserackandpinionsteeringmechanisms,wherethesteeringwheelturnsthepiniongear;
thepinionmovestherack,whichisasortoflineargearwhichmesheswiththepinion,fromsidetoside.Thismotionappliessteeringtorquetothekingpinsofthesteeredwheelsviatierodsandashortleverarmcalledthesteeringarm.
Olderdesignsoftenusetherecirculatingballmechanism,whichisstillfoundontrucksandutilityvehicles.Thisisavariationontheolderwormandsectordesign;
thesteeringcolumnturnsalargescrew(the"
wormgear"
)whichmesheswithasectorofagear,causingittorotateaboutitsaxisasthewormgearisturned;
anarmattachedtotheaxisofthesectormovesthepitmanarm,whichisconnectedtothesteeringlinkageandthussteersthewheels.Therecirculatingballversionofthisapparatusreduce