第一章發動機的工作原理和總體構造內燃機的工作原理與總體構造OperationandBasicSystems主要內容Contents發動機的定義及分類Definition&Classifications四沖程發動機及二沖程發動機的工作原理Operation發動機的基本工作系統BasicSystems發動機的產品名稱和型號編制規則ProductNamesandTypeEstablishmentRules有關概念和排量的計算Terminology&Concept1.1IntroductionTheinternalcombustion(IC)engineisaheatenginethatconvertschemicalenergyinafuelintomechanicalenergy,usuallymadeavailableonarotatingoutputshaft.內燃機是將熱能（來自于燃料化學能）轉變為機械能的一種熱機。Versussteamenginesandgasturbineenginesareexternalcombustionengines(i.e.，combustiontakesplaceoutsidethemechanicalenginesystem)外燃機

1.1發動機的定義發動機將某一種形式的能量轉化為機械能的機器。熱機（熱能機械能）外燃機內燃機燃氣輪機活塞式往復活塞式reciprocatingengines旋轉活塞式rotaryengines1.2HistoricalBackgroundForcenturies,manwalkedorusedanimalsfortransportation.After

theinventionofmechanicalpropulsionsystems,peopleusedself-

propelledvehicles,whichmoveundertheirownpower.

Majormilestonesinvehicledevelopmentinclude:

ThefirstfairlypracticalenginewasinventedbyJ.J.E.Lenoir(1822-1900)andappearedonthesceneabout1860.1876Ottowasgivencreditwhenhisprototypeenginewasbuiltin1876.1892By1892,RudolfDiesel(1858-1913)hadperfectedhiscompressionignitionen-gineintobasicallythesamedieselengineknowntoday.1.2EarlyHistory2techno-logicaloccurrencesduringlatterhalfofthe1800sstimulatedtheemergenceoftheICEIn1859,thediscoveryofcrudeoilinPennsylvaniaThepneumaticrubbertirefirstmarketedbyJohnB.Dunlopin1888.1912

ElectricstarterinventedbyCharlesF.Kettering.

FirstusedonaCadillac,thestarterwasproduced

byDaytonElectricLaboratoriesCompany

1.2EarlyHistoryThesteamengineworkingprinciple內燃機發展簡史內燃機是在蒸汽機的基礎上發明創制的：1700年，英國人鈕卡姆制成了直立汽缸，密封式活塞、缸內噴水冷卻的蒸汽機；后由瓦特改良；1814——1829年，英國人史蒂芬森制成蒸汽機車，建成世界上第一段鐵路；1860年，法國人勒納（lenoir）仿蒸汽機制成世界上第一臺商用煤氣機（?=4%）；內燃機發展簡史內燃機是在蒸汽機的基礎上發明創制的：1876年，德國人奧托制成四沖程火花點火內燃機（?=16%）；1883年，英國人司派爾仿奧托四沖程煤氣機創制汽油機；1886年，德國人奔茨制成用汽油機做動力的汽車；1892年，德國人狄塞爾創制柴油機成功，1898年，柴油機作為商品出售，熱效率為29%。1.3EngineOperationFour-StrokeSIEngineCycleIntakeorInductionStrokePowerorExpansionStrokeCompressionStrokeExhaustStroke1.3EngineOperationindicatordiagram1.3EngineOperation1、Piston-EngineConstructionPistonsmoveupanddown(orbackandforth)incylindersReciprocatingmotionischangedtorotarymotionbyconnectingrodandacrankpinonthecrankshaft2、OperationApistonstrokeisthemovementofthepistoninthecylinderfromtoptobottom,orbottomtotopFourpistonstrokes-----------intake,compression,powerandexhaust.Takestworevolutionsofthecrankshaft.Four-stroke-cycleengine1.3EngineOperationFour-StrokeCIEngineCycleIntakeorInductionStrokePowerorExpansionStrokeCompressionStroke1.3EngineOperation四沖程柴油機工作原理（seeanimation）/diesel1.htm1.3EngineOperation四沖程柴油機與汽油機比較同：四個沖程—進氣、壓縮、膨脹和排氣異：燃油，可燃混合氣形成，著火方式汽油易蒸發，柴油不易揮發混合氣形成：高壓柴油從噴油器中直接噴入氣缸，形成時間很短（燃燒室形狀，組織進氣渦流）著火方式：自燃溫度約600K（320℃）壓縮比較大。1.3EngineOperationQuestions:Whatmakestheairorair-fuelmixtureenterintothecylinder?Whatmakesthepistonsmoveupanddowninthecylinders?Whatisthepurposeofthevalves？Whatisthepropertimingofthevalves?Howdothecrankshaftandconnectingrodchangethereciprocatingmotionintorotarymotion？1.3EngineOperationAsinglecylinderfour-stroke-cycleenginehasonlyonepowerimpulseforeverytwocrankshaftrevolutions.Thepistondeliverspoweronlyone-fourthofthetime.四個沖程，只有一個行程做功，運轉不平穩；Foramoreevenflowofthepower,mostautomotiveengineshavefourormorecylinders.Thecylindersfireoneafteranothertoprovideasteadypowerflow.常采用多缸的方式;缸數曲軸做功間隔12周21周4半周8?周1.3EngineOperation1.3EngineOperationAcarengineusesafour-strokecycle--howcantwostrokesaccomplishthesametasks?想一想，兩沖程發動機怎么工作？怎樣在活塞的兩個沖程完成一個（進氣、壓縮、膨脹和排氣）完整的循環？結構特點示功圖1.3EngineOperationYoucanseethattwo-strokeenginesareingeniouslittledevicesthatoverlapoperationsinordertoreducethepartcount.1.3EngineOperationTwo-StrokeSIEnginescheduleSpecialDesignofTwo-StrokeEnginesOnonesideofthepistonisthecombustionchamber,wherethepistoniscompressingtheair/fuelmixtureandcapturingtheenergyreleasedbytheignitionofthefuel.Ontheothersideofthepistonisthecrankcase,wherethepistoniscreatingavacuumtosuckinair/fuelfromthecarburetorthroughthereedvalveandthenpressurizingthecrankcasesothatair/fuelisforcedintothecombustionchamber.Meanwhile,thesidesofthepistonareactinglikevalves,coveringanduncoveringtheintakeandexhaustportsdrilledintothesideofthecylinderwall.1.3EngineOperation兩沖程汽油機在兩個活塞行程內完成進氣、壓縮、膨脹和排氣的工作循環。1、結構三個口：進氣口、排氣口和掃氣口2、工作過程活塞上行：壓縮、進氣、點燃活塞下行：做功、結束進氣、排氣、掃氣3、總結由于特殊結構，方使得進氣、壓縮、做功和排氣得以在兩個沖程中完成；有效行程的大小與孔的位置有關。1.3EngineOperationTwo-StrokeSIEngineCycle1.3EngineOperationTwo-StrokeCIEngineCycle1.3EngineOperationTwo-StrokeoverFourStrokeSIEngineAdvantage優點：PowerStrokeeveryrevolution一周有一個做功行程，運轉均勻平穩；SimpleStructure無專門的換氣機構，使用方便。Disadvantage缺點：RemainingofExhaustGases不易將廢氣排除干凈；LessEfficientStroke有效行程小于上下止點間距離；BlowoutofAir-FuelMixture掃氣時有燃油損失。1.3EngineOperationTwo-StrokeCIEngine1、overtwo-strokeSIengine與二沖程汽油機比較，不同之處：exhaustvalves采用排氣門排氣；moreinletports進氣口不止一個，環布在氣缸周圍，且經氣泵加壓；Scavengingwithpureair采用純空氣掃氣，沒有燃油損失；separatecrankcase不用曲軸箱貯存可燃混合氣及空氣。2、工作原理Upwardstroke:scavenge,compression,spray,self-ignition活塞上行沖程：換氣、壓縮、噴油著火；Downwardstroke:expansion,exhaust,intakeandscavenge活塞下行沖程：膨脹做功、排氣換氣。1.3EngineOperation柴油機與汽油機的特點比較柴油機壓縮比大，燃氣膨脹充分，膨脹終了燃氣溫度較低，熱量利用程度較好，比汽油機省燃料。柴油機氣缸壓力較高，機件受力較大，剛度和強度要求較高，與相同功率的汽油機相比，其體積較大，重量也較大，但堅固耐用，運轉時噪聲也較大。柴油機中噴油泵和噴油氣的精密度高，加工比較困難，制造成本也較高。柴油機借助于壓縮終了空氣的高溫使柴油著火，所以較難起動。汽油機轉速較高，柴油機轉速較低。柴油機廣泛用在農用動力、拖拉機、載重汽車、工程機械、機車、船舶等方面。汽油機則由于結構輕巧、制造方便、工作平穩、起動容易等優點，常用在小客車、輕型載貨汽車及小型農用動力上。1.4Terminology術語及概念Top-Dead-Center上止點（TDC)BottomDead-Center下止點(BDC)Stroke活塞行程(S)DisplacementorDisplacementVolume排量（發動機工作容積或發動機排量）Compressionratio壓縮比Knock爆震1.4術語及概念演示1.5EngineClassificationTypesofIgnitionSparkIgnitionCompressionIgnitionEngineCyclesFour-strokecycleTwo-strokecycleAirIntakeProcessFuelUsedTypeofCooling1.5發動機的分類往復活塞式發動機兩種基本類型汽油機柴油機所用燃料著火方式混合氣準備方式發動機的其他分類按每循環沖程數/按進氣方式/按燃料/按冷卻方式按氣缸數目/按氣缸排列方式/按氣門數1.6BasicEngineSystems發動機的總體構造按照功能解體為下面幾個部分：FuelSystem燃油供給系統（）Intakesystem進氣系統（）IgnitionSystem點火系統CoolingSystem冷卻系統（）LubricatingSystem潤滑系統（）StartingSystem起動系統EmissionControlSystem排放控制系統1.6BasicEngineSystems發動機的總體構造FuelSystem燃油供給系（）Thefuelsystemsuppliesgasolineordieselfueltotheengine.Thefuelismixedwithairtomakeacombustiblemixture.Eachcylinderisrepeatedlyfilledwiththemixture.Then,themixtureisignitedandburned,producinghighpressure.Thehighpressuremakesthepistonsmove.Thisturnsshaftsthatrotatethewheels,causingthevehiclestomove.1.6BasicEngineSystems發動機的總體構造AirIntake/ExhaustSystem

進排氣系統

（）Allenginesdrawairfromtheatmosphere.AirIntake/ExhaustSystembringscleanairintotheenginefromoutsideandpushesexhaustgasestooutside.1.6BasicEngineSystems發動機的總體構造IgnitionSystem點火系統Deliveranelectricsparktoignitetheair-fuelmixture.Theactionisrepeatedmanytimeseachsecondwhiletheengineisrunning.Theignitionsystemtakesthelowvoltageofthebatteryandbuildsituptoaveryhighvoltage---ashighas47,000voltsinsomesystems.Thishighvoltagejumpsthegapsinthesparkplugs,producingthesparks.1.6BasicEngineSystems發動機的總體構造CoolingSystem冷卻系統（）Coolingsystemgivetheenginebetterheatcontrolbyremovalofthesurplusheatorwarminguptheenginequicklyatthecoldstart.1.6BasicEngineSystems發動機的總體構造LubricatingSystem潤滑系統（）Theenginehasmanymovingmetalparts.Ifmetalpartsrubagainsteachother,theywillwearrapidly.Topreventthis,engineshavelubricatingsystemsthatfloodallmovingpartswithacoatingoflubricatingoil.Theoilgetsbetweenthemetalpartssotheyslideonoilandnotoneachother.1.6BasicEngineSystems發動機的總體構造StartingSystem起動系統Thestartingsystemisneededtocranktheengine.Abatteryprovidestheelectricpowertooperatethestaringmotorandtheignitionsystemduringcranking1.6BasicEngineSystems發動機的總體構造EmissionControlSystem

Controlofvehicleemissionsincludescontrollinggasolinevaporsreleasedintotheatmosphereinadditiontoreducingexhaustemissions.發動機參數承載車輛BETA發動機DELTA發動機發動機型號伊蘭特索納塔1.6LGAS1.8LGAS2.0LGAS2.7LGAS發動機形式1-4(4缸)V-6(6缸)BORE×STROKE77.4×8582×8582×93.566.7×75排氣量(CC)1.5991.7951.9752.656最大功率(PS/rpm)112/6,000132/6,000140/6,000178/6,000缸心距9196最大扭矩(Kg.m/rpm)14.6/4,50017.1/4,50018.6/4,50025.0/4,000Engine基本組成(Assembly)AirCleanerExhaustManifoldIntakeManifoldCatalystCylinderHeadWaterPumpAirCleanerAirCleanerElementFuelRailInjectorCatalystIntakeManifoldExhaustManifoldThrottleBody進排氣系統Intake/ExhaustSystemValveTrainTimingBeltCamshaftIntake&ExhaustValveCamshaftSprocketCrankshaftSprocketValveSpringIdler配氣系統CoolingWaterCircuitThermostatThermostatHousingWaterPumpToRadiator冷卻系統曲柄連桿機構

MovingPart（主運動系統）PistonPistonRingFlywheelConnecting-RodCrankshaftMainBearingDamperPulleySIMK43PCU

O?SENSOR

3-CATALYST碳罐清污閥CKPSKNOCKSENSORTPSIGNITIONCOILFUELPUMPWTS

INJECTORCMPSISASENSORSACTUATORS新世代

A/T?β-2.0DENGINEAirMAPSSPARKPLUGCMPS:CamshaftPositionSensorCKPS:CrankshaftPositionSensorTPS:ThrottlePositionSensorWTS:WaterTemperatureSensorISA:IdleSpeedActuatorEFCENGMANAGEMENTSYSTEM構成圖ProductNames&TypeEstablishmentRules

內燃機產品名稱和型號編制規則GB/T725-1991規定；內燃機按所用燃料命名；型號由阿拉伯數碼和漢語拼音字母組成；內燃機型號由下列四部分組成首部：產品系列符號或換代標志符號；中部：缸數符號、沖程符號、汽缸排列符號和缸徑符號；后部：結構特征、用途符號尾部：區分符號TrendGDIHCCIProblems:1.1ListfivedifferencesbetweenSIenginesandCIengines.1.2Afour-strokecycleenginemay