外文翻译--马自达公司的速度感应四轮转向系统.doc

英文全文TheMazdaSpeedSensingComputerised4-WheelSteeringSystem.theMazdaSpeedSensingComputerised4-WheelSteeringTheMazdaSpeedSensingComputerised4-WheelSteeringSystem.Threeandahalfdecadesago,well-calculatedconclusionthatpresentationConference,attheOctober26,twoyoungMazdadesignersarrivedatafar-sightedandwasquiterevolutionaryforthetime.Intheirtechnical1962JapaneseAutomotiveEngineersSocietyTechnicalDrTadashiOkadaconcerningvehicledynamicsasandengineerToshiakisummarisedtheirarduousresearchfollows.1Thebasicdifferenceinthecharacteristicsofoversteerandundersteerliesinthemagnitudeoftimedelayandresponse.2.avehiclethatisstableunderhighspeedmustpossessundersteercharacteristics3.therearwheeltyrereflectsheavilyonthestabilityandamajorimprovementoncontrolandstabilitymaybeanticipatedbymeansoftheautomaticrearwheelsteeringsystem.TheconclusionsandformulationspresentedbythesetwoengineersestablishedthefoundationforMazdaspresent-dayreputedsuspensiontechnology.Overyearsofdedicatedresearchanddevelopmentexpertise,theiroriginaldiscoveriesandtheorieshavecontributedtosomeofthemostsignificantachievementswithintherecenthistoryofautomotivechassisengineering,incorporatedbyMazdawithinitsseriesproductionproducts.Thesedevelopmentsincludethetwintrapezoidallinkrearsuspension,firstemployedintheoriginalfront-wheeldriveMazda323(1980)andtheMazda626(1982,andthenperfectedwithintheupdatedMazd626；theawardwinningDynamicTrackingSuspensionSystemofthesecondgenerationMazdaRX-7(1985)；andtheelaborateE-linkrearsuspensionofthenewMazda929(1987).WhilevariousexternalforcesandloadsareexertedtotherearwheelsofavehicleasitcombatstheelementsofthelawofmotionasdefinedbySirIsaacNewton,thesenewsuspensionsystemsconvertthoseforcesinto4WSeffectswhichpositivelyaidinvehiclestabilityandagility.theMazdadesignersandengineersultimategoalwasstillapositivemeasuretogenerateforcesforpositivecontrols；aFour-WheelSteeringsystem.In1983,Mazdaastonishedtheautomotiveworldwiththeintroductionofanengineeringconceptcar,theMX-02,exhibitedattheTokyoMotorShow.Thisfour-doorSedan,withgenerouspassengeraccommodationonanunusuallylongwheelbase,incorporatedamongitsnumerousadvancedfeaturesatrue4WSsystemthataidedhigh-speedstabilityaswellasitslow-speedmanoeuvring.Thedegreeofrearwheelsteeringwasdeterminedbythemeasurementofbothfrontwheelsteeringangleandvehiclespeed,bymeansofacentralcomputerunit.TheMX-02wasfollowedbyanotherexcitingconceptcar；theMX-03,firstexhibitedattheFrankfurtMotorShowinSeptember1985.Thissleekfourseatfuturisticcoupeofthe1990scombinedarefinedelectronically-controlled4WSsystemwithacontinuallyvaryingtorque-split,four-wheeldrivesystemandapowerfulthree-rotaryengine.MazdaElectronically一ControlledFour-WheelSteeringSystem:ABeneficialTechnologyMazdaselectronically-controlled,vehicle-speed-sensingFour-WheelSteeringSystem(4WSsteerstherearwheelsinadirectionandtoadegreemostsuitedtoacorrespondingvehiclespeedrange.Thesystemismechanicallyandhydraulicallyactuated,producinggreatlyenhancedstability,andwithincertainparameters,agility.ThedriverofaMazda4W5-equippedcarderivesfivestrategicbenefits,overandabovetheconventionalvehiclechassis.1.Superiorcorneringstability2.Improvedsteeringresponsivenessandprecision3.High-speedstraightlinestability4.Notableimprovementinrapidlane-changingmanoeuvres5.Smallerturningradiusandtight-spacemanoeuvrabilityatlowvehiclespeedrangeThemostoutstandingadvantageoftheMazda4WSisthatitcontributestoanotablereductionindriverfatigueoverhigh-speedandextendedtravelling.Thisisachievedbyoptimally:1.reducingtheresponsedelaytosteeringinputandactionand2.eliminatingthevehiclesexcessivereactiontosteeringinputInessence,byprovidingtheoptimumsolutiontothephenomenaresearchedbythetwoyoungMazdaengineersintheearlysixties一bythemethodadvocatedbythem一the4WSsystemhasemergedasafullybeneficialtechnology.StrategicConstructionTheMazda4WSconsistsofarack-and-pinionfrontsteeringsystemthatishydraulicallyassistedbyatwin-tandempumpmainpowersource,withanoverallsteeringratioof14.2:1.Therearwheelsteeringmechanismisalsohydraulicallyassistedbythemainpumpandelectronicallycontrolled一accordingtothefrontsteeringangleandvehiclespeed.Therearsteeringshaftextendsfromtherackbarofthefrontsteeringgearassemblytotherearsteering-phasecontrolunit.Therearsteeringsystemiscomprisedoftheinputendoftherearsteeringshaft,vehiclespeedsensors,asteering-phasecontrolunitdeterminingdirectionanddegree),apowercylinderandanoutputrod.Acenteringlockspringisincorporated,whichlockstherearsysteminaneutral(straightforwardpositionintheeventofhydraulicfailure.Additionally,asolenoidvalvethatdisengageshydraulicassist(therebyactivatingthecenteringlockspringincaseofanelectricalfailureisineluded.The4WSsystemvariesthephaseandratiooftherear-wheelsteeringtothefrontwheels,accordingtothevehiclespeed.Itsteerstherearwheelstowardtheoppositephase(directionofthefrontwheelduringspeedslessthan35kmlh(22mphforatighterturnandneutralizesthem(toastraightforwarddirection,asinaconventionaltwo-wheelsteeringprincipleat35kmlh(22mph.Abovethatspeed,thesystemsteerstowardthesamephase-directionasthefrontwheels,therebygeneratinganincreasedcorneringforceforstability.Themaximunsteeringangleoftherearwheelsextends5degreestoeitherleftorright,ameasurementth敏Mazdahasdeterminedtobeoptimallyeffectiveandnaturaltohumansensitivity.PrimaryComponents1.VehiclespeedsensorsInterpretspeedometershelfrevolutionsandsendsignaltotheelectroniccomputerunit.twosensors,onewithinthespeedometerandtheotheratthetransmissionoutput,areusedtocrosschecktheotherforaccuracyandfailsafemeasures.2.SteeringphasecontrolunitConveystothepowersteeringcylinderboostervalvethedirectionandstrokeofrearwheelsteeringbythecombinedmovementofthecontrolyokeangleandbevelgearrevolutions.3.ElectricsteppermotorPerformsalteringoftheyokeangleandbevelgearphasing4.RearsteeringshaftTransmitsfrontwheelsteeringanglebyturningthesmallbevelgearinthesteeringphasecontrolunit,whichrotatesthemainbevelgearintheassembly.5.ControlvalveFeedshydraulicpressuretothesteeringactuator,accordingtothephaseandstrokerequiredforappropriaterearwheelsteering.6.Hydraulicpowercylin