燃油喷射系统外文文献翻译、中英文翻译

附录附录A英文文献与中文参考译文A1FuelinjectionsystemsA1.1GeneralinformationFuelinjectionsystemshavebeenusedonvehiclesformanyyears.Theearliestoneswerepurelymechanical.Astechnologyadvanced,electronicfuelinjectionsystemsbecamemorepopular.Earlymechanicalandelectronicfuelinjectionsystemsdidnotusefeedbackcontrols.Asemissionsbecamemoreofaconcern,feedbackcontrolswereadaptedtobothtypesoffuelinjectionsystems.Bothmechanicalandelectronicfuelinjectionsystemscanbefoundongasolineengines.A1.2Multi-portfuelinjectionsThisisthemostcommontypeoffuelinjectionsystemfoundtoday.Regardlessofthemanufacturer,theyallfunctioninthesamebasicway.Onthesesystemsanequalamountoffuelisdeliveredtoeachcylinder.Thesesystemsallusesensorswhichtransmitoperatingconditionstothecomputer.Informationfromthesesensorsisprocessedbythecomputerwhichthendeterminestheproperair/fuelmixture.Thissignalissenttothefuelinjectorswhichopenandinjectfuelintotheirports.Thelongertheinjectorisheldopen,thericherthefuelmixturewillbe.Mostfuelinjectionsystemsneedthefollowinginformationtooperateproperly.Temperaturesensors-thisincludesbothairandcoolanttemperature.Thecomputerdeterminehowrichorleanthemixtureshouldbe.Thecolderthetemperature,thericherthemixture.Throttlepositionsensorsorswitches-thecomputerusesthisinformationtodeterminethepositionofthethrottlevalve(s).Somevehiclesusesensorswhichrelaytheexactpositionofthethrottlevalve(s)atalltimes.Othersuseswitcheswhichonlyrelayclosedandwide-openthrottlepositions(somemayalsouseamid-throttleswitch).Theseswitchesandsensorshelpdetermineengineload.Airflowsensors-thesesensorsalsohelpthecomputerdetermineengineloadbyindicatingtheamountofairenteringtheengine.Thereareseveraldifferenttypesofairflowsensors,butintheend,theyalldothesamejob.Manifoldpressuresensors-ifavehicleisnotequippedwithanairflowsensor,itusesamanifoldpressuresensortodetermineengineload(Notethatsomevehicleswithanairflowsensormayalsohaveamanifoldpressuresensor.Thisisusedasafail-safeiftheairflowsensorfails).Asengineloadincreases,sodoesintakemanifoldairpressure.Enginespeedandpositionsensors-enginespeed/positionsensorscanbereferencedformthecrankshaft,camshaftorboth.Inadditiontohelpingdetermineengineload,thesesensorsalsotellthecomputerwhentheinjectorsshouldbefired.Thesesystemsoperateatarelativelyhighpressure(usuallyatleast30psi).Tocontrolthefuelpressure,afuelpressureregulatorisused.Asengineloadincreases,morefuelpressureisneeded.Thisisduetotherichermixture(morefuelneeded)andtoovercometheincreasedairpressureintheports.Anyunusedfuelisdivertedbacktothefueltankusingareturnline.A2.IgnitionsystemTherearemanydifferenttypesofignitionsystems.Mostofthesesystemscanbeplacedintooneofthreedistinctgroups:theconventionalbreakerpointtypeignitionsystems(inusesincetheearly1900s);theelectronicignitionsystems(popularsincethemid70s);andthedistributorlessignitionsystem(introducedinthemid80s).Theautomotiveignitionsystemhastwobasicfunctions:itmustcontrolthesparkandtimingofthesparkplugfiringtomatchvaryingenginerequirements,anditmustincreasebatteryvoltagetoapointwhereitwillovercometheresistanceofferedbythesparkpluggapandfiretheplug.A2.1HowdoestheignitionsystemworkAnautomotiveignitionsystemisdividedintotwoelectricalcircuits—theprimaryandsecondarycircuits.Theprimarycircuitcarrieslowvoltage.Thiscircuitoperatesonlyonbatterycurrentandiscontrolledbythebreakerpointsandtheignitionswitch.Thesecondarycircuitconsistsofthesecondarywindingsinthecoil,thehightensionleadbetweenthedistributorandthecoil(commonlycalledthecoilwire)onexternalcoildistributors,thedistributorcap,thedistributorrotor,thesparkplugleadsandthesparkplugs.Thedistributoristhecontrollingelementofthesystem.Itswitchestheprimarycurrentonandoffanddistributesthecurrenttothepropersparkplugeachtimeasparkisneeded.Thedistributorisastationaryhousingsurroundingarotatingshaft.Theshaftisdrivenatone-halfenginespeedbytheengine’scamshaftthroughthedistributordrivegears.Acamnearthetopofthedistributorshafthasonelobeforeachcylinderoftheengine.Thecamoperatesthecontactpoints,whicharemountedonaplatewithinthedistributorhousing.Arotorisattachedtothetopofthedistributorshaft.Whenthedistributorcapisinplace,aspring-loadedpieceofmetalinthecenterofthecapmakescontactwithametalstripontopoftherotor.Theouterendoftherotorpassesveryclosetothecontactsconnectedtothesparkplugleadsaroundtheoutsideofthedistributorcap.Thecoilistheheartoftheignitionsystem.Essentially,itisnothingmorethanatransformerwhichtakestherelativelylowvoltage(12volts)availablefromthebatteryandincreasesittoapointwhereitwillfirethesparkplugasmuchas40000volts.Theterm“coil”isperhapsamisnomersincethereareactuallytwocoilsofwirewoundaboutanironcore.Thesecoilsareinsulatedfromeachotherandthewholeassemblyisenclosedinanoil-filledcase.Theprimarycoil,whichconsistsofrelativelyfewturnsofheavywire,isconnectedtothetwoprimaryterminalslocatedontopofthecoil.Thesecondarycoilconsistsofmanyturnsoffinewire.Itisconnectedtothehigh-tensionconnectionontopofthecoil(thetowerintowhichthecoilwirefromthedistributorisplugged).Undernormaloperatingconditions,powerfromthebatteryisfedthrougharesistororresistancewiretotheprimarycircuitofthecoilandisthengroundedthroughtheignitionpointsinthedistributor(thepointsareclosed).Energizingthecoilprimarycircuitwithbatteryvoltageproducesproducescurrentflowthroughtheprimarywindings,whichinducesaverylarge,intensemagneticfield.Thismagneticfieldremainsaslongascurrentflowsandthepointsremainclosed.Asthedistributorcamrotates,thepointsarepushedapart,breakingtheprimarycircuitandstoppingtheflowofcurrent.Interruptingtheflowofprimarycurrentcausesthemagneticfieldtocollapse.Justascurrentflowingthroughawireproducesamagneticfield,movingamagneticfieldacrossawirewillproduceacurrent.Asthemagneticfieldcollapsesitslinesofforcecrossthesecondarywindings,inducingacurrentinthem.Sincetherearemanymoreturnsofwireinthesecondarywindings,thevoltagefromtheprimarywindingsismagnifiedconsiderablyupto40000volts[18,19].参考译文：A1.燃油喷射系统A1.1燃油喷射系统概述燃料喷射系统已经在汽上车使用了许多年。最早的部分是纯粹机械的。对于先进的技术，电子燃料喷射系统变得更加普遍。早期的机械式和电子式燃料喷射系统没有使用反馈控制。当今与排放越来越相关，两种燃油喷射系统反馈控制都适应。机械和电子式燃料喷射系统在汽油发动机上比较长见。A1.2多点燃油喷射系统这是今天被使用的燃料喷射系统中最普通的类型。所有的制造商，他们都使用同一个基本的方式。它是将等量的混合气分配到各个气缸中。燃油系统都是通过传感器输送的信号给计算机控制。通过计算机处理传感器的信号，然后确定适当的空燃比。然后将喷油信号送给喷油器，控制喷油器的开启和关闭。喷油器打开的时间越长，进入气缸的混合气越多。大部分燃油喷射系统需要以下传感器信号正常运作。温度传感器，这里面包括空气和冷却液的温度。计算机通过温度传感器来确定混合气的浓度。低温时，使混合气变浓。节气门位置传感器，电脑根据此信号来确定节气门的开闭。一些车辆在任何时候都使用节气门位置传感器，从而确定节气门的具体位置。其他车辆使用传感器确定节气门关闭和节气门打开位置（有些还可以使用怠速开关）。这些开关和传感器，帮助确定发动机负荷。空气流量传感器，该传感器还有助于计算机确定发动机的进气量，用于表示发动机负荷。有几种不同类型的空气流量计，不过，他们的作用是相同的。进气压力传感器，如果车辆没有配备空气流量传感器，则它采用了进气压力传感器，以确定发动机负荷（请注意，一些车辆的空气流量传感器也可能有进气压力传感器。这是作为一个空气流量传感器故障的后备安全故障）。进气歧管空气压力增大则表示发动机负荷增大。发动机的转速和位置传感器，发动机转速和位置传感器可从曲轴、凸轮轴得到信号。除了可以确定发动机负荷，还可以通过传感器确定进气量。燃油喷射系统工作在一个相对较高的压力（通常至少30磅）环境下。燃油压力调节器用来控制燃油压力，使燃油压力保持恒定。如果发动机负