4-汽车专业英语课件-汽车设计制造部分-section 4汽车专业英语2版ppt课件--20180227补充-- clutch design

复习,提问（教师说发动机底盘部件名称，同学回答英文名称）,Chapter11AutomotiveDesign,DesignofDryClutchesEngineandTransmissionMatching11.1Changingratios-matchingofthetransmissiontothevehicle11.2Brakingsystemdesignmethodology;11.4DevelopingandTestingtheEngineManagementSoftware11.3StartingSystemDesign,Chapter11AutomotiveDesignDesignofDryClutches,1,学习内容,本节课学习内容、目标和重点难点,学习目标,难点重点,AutomotiveDesignDesignofDryClutches,1.掌握有关离合器设计的专业术语与词汇2.掌握长句分析要点，提高翻译技巧3.了解离合器设计需要考虑的几个重要问题,1.重点：长句翻译方法；相关术语的记忆2.难点：长句翻译,AutomotiveDesignDesignofDryClutches,Reviewclutchstructure,2,AutomotiveDesignDesignofDryClutches,Reviewclutchstructure（translatethefollowingChinesetermsintoEnglish）,离合器压盘飞轮盖压紧弹簧离合器从动盘从动盘摩擦衬片,2,AutomotiveDesignDesignofDryClutches,3,AutomotiveDesignDesignofDryClutches,4,AutomotiveDesignDesignofDryClutches,Whendeterminingclutchsize,boththeabilitytotransferthemaximumamountofinputtorquewithsufficientreliabilityandtheanticipatedthermalloadcausedbyheatingduringmoving-offandshiftingarecrucialfactors.,5,长句翻译方法1.拆分（化整为零，各个击破）：在“通读全文，明确词义，弄清语法，理解大意”过程中，要将句子切分成若干个部分（句子、分词短语、动词不定式短语、介词短语等），并分别加以理解和表达；2.整合（合零为整，组合润色）：弄清各部分之间的修饰关系，并据此和汉语习惯进行组合表达。,AutomotiveDesignDesignofDryClutches,Whendeterminingclutchsize,boththeabilitytotransferthemaximumamountofinputtorquewithsufficientreliabilityandtheanticipatedthermalloadcausedbyheatingduringmoving-offandshiftingarecrucialfactors.,5,长句翻译方法1.拆分（化整为零，各个击破）,拆分成8个部分：,每个部分的含义：,1当确定离合器尺寸时/2能力/3传递最大输入转矩/4具有足够的可靠性/5预期热负荷/6由加热（摩擦生热）所引起的/7在起步和换挡期间/8是至关重要的两个因素注意both-and搭配,AutomotiveDesignDesignofDryClutches,Whendeterminingclutchsize,boththeabilitytotransferthemaximumamountofinputtorquewithsufficientreliabilityandtheanticipatedthermalloadcausedbyheatingduringmoving-offandshiftingarecrucialfactors.,5,长句翻译方法2.整合（合零为整，组合润色）：弄清各部分之间的修饰关系，并据此和汉语习惯进行组合表达。,弄清语法关系：,组合表达：,1（当）确定离合器尺寸时，4（具有足够的）可靠（性）地3传递最大输入转矩的2能力和7（在）起步与换挡期间6由摩擦生热所引起的5预期热负荷8是至关重要的两个因素。,1当确定离合器尺寸时/2能力/3传递最大输入转矩/4具有足够的可靠性/5预期热负荷/6由加热（摩擦生热）所引起的/7在起步和换挡期间/8是至关重要的两个因素注意both-and搭配,AutomotiveDesignDesignofDryClutches,1/DesignCalculationsTheclutchmusttransmitthemaximumenginetorqueincludingexcessivedynamicincreases.TheclutchtorquetobetransferredTcisdependentonthepressureforceofthepressureplate,thefrictioncoefficientofthefrictionlining,theaveragefrictionradiusandthenumberoffrictionsurfaces:,5,frictioncoefficient.znumberoffrictionsurfaces:single-plateclutchz=2,two-plateclutchz=4.,AutomotiveDesignDesignofDryClutches,6,FaxPressureforceofthepressureplate(N),rmaveragefrictionradius(m),rmiscalculatedfromtheouterandinnerfrictionsurfaceradiusroandriasfollowingequation,AutomotiveDesignDesignofDryClutches,Thefrictioncoefficientsforstaticfriction(fullyengagedclutch)andfordynamicfriction(duringslip)arenearlyidenticalandarebetween0.3and0.45fororganicfrictionlinings.Inthecaseofextremethermaloverloading-fading-thecoefficientcandroptolessthan0.2.Tocoverfrictioncoefficientdeteriorationduringextremefadingaswellaspressureforcedroppingcausedbyrelaxationofthediaphragmspring,returnspringforce,thecentrifugalforceofthediaphragmspringtongues,frictionandpreloadintheactuationsystem,asafetyfactorSisintroduced.,7,AutomotiveDesignDesignofDryClutches,ThesafetyfactorSistheratiooftheclutchtorquetobetransmittedtothemaximumenginetorqueTM,max.Itliesbetween1.2S1.4:,Figure1showsthebandwidthsofpracticaldesignsforpassengercarsandcommercialvehiclesasafunctionoftheclutchplatediameter.Exactcalculationofshiftable（可拆换的）,externallyactuatedfrictionclutchesfollowsVDIguideline2241,page1.Theotherliteratureisalsohelpfulinthecalculationprocess.,8,AutomotiveDesignDesignofDryClutches,Fig.1Bandwidthsofpracticalclutchdesignsforapassengercars/vansandbcommercialvehicles.*two-plateclutch,9,AutomotiveDesignDesignofDryClutches,2/ThermalBalanceTheservicelifeoffrictionliningsiscrucialfortheservicelifeofamotorvehiclesclutch.Theservicelifeoffrictionliningsdependsonthetemperature,loadduration,thequalityoftheliningsandtheamountofwear.Moreover,theoperationofthedryclutchalsohasalotofinfluenceontheservicelifeofthefrictionlinings,whichcanbeseenastheweakestlinkinthewearchain.,10,AutomotiveDesignDesignofDryClutches,Inthecaseofthermalloadingofthedryclutch,aconsiderationofthermalbalanceoftheentireclutchsystemismandatory（强制的，法定的）.Here,theaddedheatisrelatedtotheheatcapacityoftheclutch(pressureplate,flywheel)andthedissipatedheat.Thetemperatureofthepressureplateisadecisivecriterion（判据，准则）,sinceitgenerallyhaslessheatcapacitythantheflywheelanditscoolingisimpaired（削弱）bythesurroundingpressureplatehousing.3/LoadLimitsAslongastheclutchofamotorvehicleissufficientlydimensionedmechanicallyanddesignedwithaneyetowear,temperaturewillbethecriticalloadlimit.Aslongas只要，直到为止,11,AutomotiveDesignDesignofDryClutches,Toassess（估算）load,thevalueofsurface-specificshiftenergyisconsulted.Table1showsempiricallyestablishedfiguresforthemaximumallowedshiftenergyrelativetothefrictionsurface.,12,Table1Maximumallowedshiftenergyrelativetothefrictionsurfaceswhenusingorganicclutchlinings,AutomotiveDesignDesignofDryClutches,Thepermissibletemperatureofthepressureplateislimitedbythereductioninpressureforceinducedbytherelaxationofthediaphragmspring.However,itisgenerallyhigherthanthemaximumallowedtemperatureoftheclutchplate.Thisisdecisivefortheservicelifeofthetribologicalsystem，especiallythefrictionlinings.Thelimittemperatureisdefinedhereasthehighesttemperatureatwhichtheclutchisstilloperative.However,thisalsoimpliesthefactthat,whenthelimittemperatureofthefrictionliningisreached,thesurfaceisalreadyirreversiblydamaged.Only