1、UUNITNIT5 5A AUTOMOBILEUTOMOBILE ELECTRICALELECTRICAL SYSTEMSYSTEM汽车电气系统汽车电气系统授课教师：授课教师：LESSON 1 THE OVERVIEW OF AUTOMOBILE ELECTRICAL SYSTEM汽车电器系统概述Learning Objectives（学习目标）（学习目标）Learn about the constitution and characteristic of vehicles electrical system.Learn about the functioning of the cars el
2、ectrical system.Grasp the new words and useful expressions.PART ONE：STIMULATE STUDENTS INTEREST（激发兴趣）There are many electrical components in the car.Look at the following picture carefully and try to introduce it to your classmates.PART TWO-STUDY PREPARATION（学习准备）1.New Words to learn（单词学习）（单词学习）Batt
3、ery btri n.电池generator den reit n.发电机horn h:n n.喇叭illumination ilju:mnein n.照明supply splaiv.提供cooperation kupren n.合作，协作，协助，配合circuit s:kt n.电路，线路;material mtiril n.材料，原料;constitution knsttju:n n.建立，组成;summarizesmraz vt.总结，概述;categorize ktgraz把归类Phrase learning（短语学习）2.Proper Names(专有名词专有名词)FUSE 保险丝或
4、精熔断器；DOME 室内灯系统；STOP 停车灯系统；HORN 扬声器；ST 起动机；A/C 空调系统；EFI 电子控制燃油喷射系统；AIRSUS 空气悬架系统；ABS 制动防抱死系统；PART TWO-STUDY PREPARATION（学习准备）ECU 电子控制单元保险丝；POWER 电动车窗控制系统；CBDOOR 电动门锁控制系统；FL RAD FAN 散热器风扇；HTR 加热器系统；HEADRHLWR：右前照灯近光；HEADLHLWR：左前照灯近光；HEADRHUPR：右前照灯远光；PART TWO-STUDY PREPARATION（学习准备）3.Phrase learning（短语
5、学习）（短语学习）content of 内容be the symbol of 是的象征according to 根据a variety of 大量的、各种the most important 最重要的refers to 指的是and so on 等等such as 例如be made up of 由组成transform into 将转换成PART TWO-STUDY PREPARATION（学习准备）PART THREE-TEXT(阅读资料)The constitution and characteristic of vehicles electrical systemAutomotive
6、electrical system is an important part of the car,whose performance directly affects the dynamic quality,economical efficiency,reliability,safety,and comfort and emission performance.Automotive electrical system is an important symbol of the development level of modern vehicles and,scientific and te
7、chnological content of vehicles has become one of the important indicators to measure the grade level of the modern automobiles.With the development of technology,integrated circuits and micro computers are widely used in automobiles.The number of electrical appliances is increasing,the power is inc
8、reasing and the quality of products and performance are improving,the structure tends to be more perfect.Its necessary that vehicle maintenance workers should understand and master the structure of materials,the identification of the spare parts and their principles,and that receive,dispatch and kee
9、p the parts correctly.PART THREE-TEXT(阅读资料)I.The constitution of the vehicles electrical systemIn terms of the electrical system in modern vehicles,it can be summarized and categorized into the following four parts:（1）Power systemThe power supply system includes a battery,a generator and regulator.T
10、he first two parts are parallel.The main power is generator and battery is an auxiliary power supply.Generator with a regulator automatically adjusts the output voltage of the generator when the generator speed increases,so that it remains stable.PART THREE-TEXT(阅读资料)（2）Power consumption systemThe p
11、ower consumption system can roughly be categorized into the following genres:1）Starter System:the main part is the starter,whose task is to start the engine.2）Ignition system:it is part of the gasoline engine,including all components of an electronic ignition system or conventional ignition system.I
12、ts mission is to produce high-voltage spark,according to the working order of the engine ignited combustible mixture within the cylinder.PART THREE-TEXT(阅读资料)3）Lighting system:it includes a variety of lights inside and outside the vehicle and ensures the inevitable lighting for safe driving at night
13、,among which head lighting is the most important.Military vehicles add the anti-aircraft lighting.4）Signal system:it includes electric horn,buzzer,flasher lights and other various signal lamps,which are the necessary signals mainly used to ensure safe driving.PART THREE-TEXT(阅读资料)5）Electronic contro
14、l system:it mainly refers to the computer-controlled apparatus,comprising of an electronic ignition control device,electronically controlled fuel injection device,the electronic control anti-lock brakes,electronically controlled automatic transmission,etc,which are respectively used to improve vehic
15、les dynamic quality,economical efficiency,security,handle the exhaust purification,automation and so on.PART THREE-TEXT(阅读资料)6）Auxiliary equipment:this part includes electric wipers,cold starting preheating device,air conditioners,tape recorders,cigarette lighter,anti-theft devices,window glass lift
16、er,seat adjuster and the like.Auxiliary electrical appliances have a tendency to increase and move mainly towards the development of comfort,entertainment,safety protection.PART THREE-TEXT(阅读资料)(3)Detection System It includes a variety of instrumentation such as voltmeter,ammeter,water temperature g
17、auge,oil pressure gauge,fuel gauge,speedometer,engine tachometer and various warning lights for monitoring the work of the engine and other devices.PART THREE-TEXT(阅读资料)(4)Power Distribution SystemPower distribution system is made up of central junction box,circuit switches,safety device,connector c
18、lip and wire,so as to ensure the reliability and safety of the line work.PART THREE-TEXT(阅读资料)2.The types of battery(1)FunctionBattery is a kind of reversible low-voltage DC power supply,an important part of the car.Battery can transform chemical energy into electrical energy and electric energy can
19、 also be converted to chemical energy.Its role is to:PART THREE-TEXT(阅读资料)1)When starting the engine,starter supplies a large current,so it is called starter-typed battery.2)Provide power for the electrical equipment under the conditions that generator does not generate electricity or generate low v
20、oltage.3)When electrical equipment consumes more than generator can afford in a short time,it assists the generator to supply power to electrical equipment.4)When battery power is low and the load of generator is small,it can transform the electrical energy into chemical energy and store the electri
21、city(ie,charge).PART THREE-TEXT(阅读资料)In addition,the battery is equivalent to a large capacitor,it can absorb the over-voltage generator at any time,protecting the transistor and prolonging its lifespan.TypesAccording to its external structure,the battery can be divided into rubber and plastic groov
22、e battery.And according to its property,the battery can be categorized into drained-charged battery,dry-charged battery and maintenance-free battery,etc.At present,lead-acid battery which is dry-charged and maintenance-free is widely used in the vehicles.PART THREE-TEXT(阅读资料)PART FOUR-DIALOGUE EXERC
23、ISE（对话练习）Situation:The following dialogue is between a customer,Cherry,and a repairman,Mr.Liu.Read it aloud and try to act it out.Customer:Hello!Repairman:Hi!Customer:My speedometer does not work.Repairman:When did you lubricate the speedometer-head last time?Customer:I can not remember that.About o
24、ne year ago.Repairman:Speedometers need periodic maintenance.We should lubricate the head once a year.Customer:How to do that?Repairman:Pull the cluster out,disconnect the cable,and feed modest doses of lubricant into the head.Customer:Oh,is it difficult?Repairman:No,I will get somebody to repair th
25、at at once.Customer:Ok,thank you.Repairman:Not at all.PART FOUR-DIALOGUE EXERCISE（对话练习）PART FIVE-NOTES TO THE TEXT(难点解析)1.Automotive electrical system is an important symbol of the development level of modern vehicles and,scientific and technological content of vehicles has become one of the importa
26、nt indicators to measure the grade level of the modern automobiles.汽车电气系统是衡量现代汽车发展水平的一个重要标志，其科技含量已成为衡量现代汽车档次的重要指标之一的标志。2.Its necessary that vehicle maintenance workers should understand and master the structure of materials,the identification of the spare parts and their principles,and that receive,
27、dispatch and keep the parts correctly.汽车维修工应了解和掌握电气系统的构造、配件识别方法及原理，对其进行正确收发与保管是十分必要的。3.The power supply system includes a battery,a generator and regulator.电源系统包括蓄电池、发电机及其调节器。4.Its mission is to produce high-voltage spark,according to the working order of the engine ignited combustible mixture withi
28、n the cylinder.其任务是产生高压电火花，按发动机的工作顺序点燃气缸内的可燃混合气。5.Battery is a kind of reversible low-voltage DC power supply,an important part of the car.Battery can transform chemical energy into electrical energy and electric energy can also be converted to chemical energy.蓄电池是一种可逆的低压直流电源，是汽车电源的重要组成部分。蓄电池既能将化学能转
29、换为电能，也能将电能转换为化学能。PART FIVE-NOTES TO THE TEXT(难点解析)6.When starting the engine,starter supplies a large current,so it is called starter-typed battery.起动发动机时，供给起动机大电流，故称为起动型蓄电池。7.When battery power is low and the load of generator is small,it can transform the electrical energy into chemical energy and
30、 store the electricity(ie,charge).蓄电池存电不足，而发电机负载又较小时，它可将发电机的电能转变为化学能储存起来(即充电)。PART FIVE-NOTES TO THE TEXT(难点解析)LESSON2ELECTRONICFUELINJECTIONSYSTEM电电控燃油喷射系统控燃油喷射系统Learning Objectives(学习目标学习目标)Learn about the definition of Automobile EFI.Learn about the operating conditions of Automobile EFI.Learn ab
31、out the structure and the components of the electronic fuel injection system.Learn about the three main systems of the electronic fuel injection system.Grasp the main terms about the electronic fuel injection system.PARTONESTIMULATESTUDENTSINTEREST(激激发兴趣发兴趣)The electronic fuel injection system has m
32、any components.They include fuel delivery system，air induction system，and electronic control system Look at the following picture and guess their English names.PARTTWO-STUDYPREPARATION（学习准备）（学习准备）1.New words to learn actuatorktjueitn.激励者;电脑执行机构;description dskripnn.描述;形容;种类;类型;flowfluvi.流;垂;流出;harne
33、ss h:ns n.电线束，导线束meter mi:t n.计量器;计量仪;modulemdju:l n.模块;组件;speed spi:d n.速度;快速;wiringwari n.配线，布线;logistics ludistiks n.后勤，逻辑学detection dtekn n.侦查;察觉;发觉;检查;manifold mnfuld n.具有多种形式的东西;多支管;歧管（汽车引擎用于进气或排气）;mass msn.大量，大多;injection ndekn n.注射;注射剂;2.Phrase learning（短语学习）（短语学习）air-fuel mixture 可燃混合器ECU=e
34、lectronic control unit 电控单元（模块）high-load 高负荷，大负荷operating condition 工作状况，工况theoretical air-fuel ratio 理论空燃比warm-up 热车，暖车PARTTWO-STUDYPREPARATION（学习准备）（学习准备）PART THREE-TEXT(阅读资料)The electronic fuel injection system can be divided into three basic subsystemsThey are the fuel delivery system，air induct
35、ion system，and the electronic control system1.Fuel Delivery System The fuel delivery system(Fig.5-1)consists of the fuel tank，fuel pump，fuel filter,fuel delivery pipe(fuel rail)，fuel injector,fuel pressure regulator,and fuel return pipe Fuel is delivered from the tank to the injector by means of an
36、electric fuel pumpThe pump is typically located in or near the fuel tankContaminants are filtered out by a high capacity inline fuel filterFuel is maintained at a constant pressure by means of a fuel pressure regulatorAny fuel which is not delivered to the intake manifold by the injector is returned
37、 to the tank through a fuel return pipePART THREE-TEXT(阅读资料)2.Air Induction SystemThe air induction system(Fig.5-2)consists of the air cleaner，air flow meter,throttle valve，air intake chamber,intake manifold runner，and intake valveWhen the throttle valve is opened，air flows through the air cleaner,t
38、hrough the air flow meter(to L type systems)，past the throttle valve，and through a well tuned intake manifold runner to the intake valveAir delivered to the engine is a function of driver demandAs the throttle valve is opened further,more air is allowed to enter the engine cylinder PART THREE-TEXT(阅
39、读资料)PART THREE-TEXT(阅读资料)3.Electronic Control SystemThe electronic control system(Fig.5-3)consists of various engine sensors，ECU，fuel injector assemblies，and related wiring PART THREE-TEXT(阅读资料)The EFI system uses various sensors to detect the operating conditions of the engine and the vehicle.In ac
40、cordance with the signals from these sensors,the ECU calculates the optimal fuel injection volume and operates the injectors in order to inject the proper volume of fuel.PART THREE-TEXT(阅读资料)The ECU determines precisely how much fuel needs to be delivered by the injector through monitoring the engin
41、e sensorsThe ECU turns the injectors on for a precise amount of time，which is reffered to as injection pulse width or injection duration，to deliver the proper air-fuel ratio to the engineAt other times,such as during warm-up,acceleration,deceleration,or high-load driving conditions,the engine ECU de
42、tects those conditions with the various sensors and then corrects the fuel injection volume in order to ensure an optimal air-fuel mixture at all time.PART THREE-TEXT(阅读资料)There are two types of EFI system classified by the intake air detection method.L-EFI(Air-flow control type)This type uses an ai
43、r-flow meter to detect the amount of the air flowing in the intake manifold.There are two types of detection methods:One directly measures the intake air mass,and one makes corrections based on the air volume.PART THREE-TEXT(阅读资料)D-EFI(Manifold pressure control type)This type measures the pressure i
44、n the intake manifold to detect the amount of the intake air using the intake air density.PART THREE-TEXT(阅读资料)PART FOUR-DIALOGUE EXERCISE（对话练习）Situation:The following dialogue is between Tom,a car salesman and Jack,a customer.They are talking about the car.Tom:What can I do for you?Jack:I bought a
45、car from your company about a year ago.Now it seems something is wrong with the battery.Tom:Can you give me more details?Jack:Well,Iv been in Changchun for the last two months and left my car parked in a garage.When I came back,it was difficult to get it started.Tom:Well,the batteries are not happy
46、at low temperatures,especially when they are not being used for long periods.Jack:Then,What should I do?Tom:You should take the battery out of the car when its not being used for a long time.Jack:Thank you for your help.Tom:My pleasure.If youd like the battery checked,bring it in.Jack:OK,Ill do that
47、.Thank you.Tom:See you.PART FOUR-DIALOGUE EXERCISE（对话练习）PART FIVE-NOTES TO THE TEXT(难点解析)1.TheEFI system uses various sensors to detect the operating conditions of the engine and the vehicle.电控燃油喷射系统通过各种传感器检测发动机和汽车的工作状况。2.At other times,such as during warm-up,acceleration,deceleration,or high-load d
48、riving conditions,the engine ECU detects those conditions with the various sensors and then corrects the fuel injection volume in order to ensure an optimal air-fuel mixture at all times.在暖机、加速、减速、高负荷运转等其他工况下，发动机控制单元通过各种传感器确定工作情况，及时修正喷油量，以始终保证最佳空燃比。3.There are two types of detection methods:One directly measures the intake air mass,and one makes corrections based on the air volume.检测方法有两种：一种是直接检测进气量，另一种是通过测量进气体积换算。
