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1、汽车实用英语,Automobile English,Task Three Automobile Engine ,Objectives 1. To know the engine crankshaft and connecting rod assembly. 2. To know the valve and valve train. 3. To learn the Automobile cooling system. 4. To learn how the lubrication system works.,2,1,1. _,2. _,Engine Construction,Fuel Syste
2、m,Part Warm upKnow about two mechanisms and five systems,3,1,3. _,4. _,Cooling System,Lubricating System,Part Warm upKnow about two mechanisms and five systems,4,1,5. _,6. _,Starting System,Ignition System,Part Warm upKnow about two mechanisms and five systems,5,Grasp the useful words and phrases fu
3、el consumption equip with,Part Listening and speaking,6,A: Hi，this is my new car. I bought it last month. B: Oh! Its beautiful. How is the fuel consumption? A: Its very economic on fuel. B: What kind of engine does the car have? A: Its equipped with an advanced diesel engine. B: Diesel engine? A: Ye
4、ah. B: Thats incredible! A: You can try it. B: OK，thank you.,Part Listening and speakingDialogue A New Diesel Car,7,Engine crankshaft and connecting rod assembly is one of the assemblies in the engine. It converts thermal energy into mechanical energy used to drive the vehicle. This assembly is comp
5、osed of pistons，piston rings，connecting rods and crankshafts.,Part ReadingPassage One Crankshaft and Connecting Rod Assembly,8,Engine valve and valve train is the other assembly in the engine. The valve and valve train provides timely admission of the fresh charge into the cylinders and exhaust gas
6、from them. For this purpose，the valves at definite moments open and close the intake and exhaust ports in the cylinder head，through which the cylinders connect to the intake and exhaust manifold.,Part ReadingPassage One Valve and Valve Train,9,The valve and valve train consists of the valves and a m
7、echanism that opens and closes them. This typical train is composed of valve，valve spring，valve guide，tappet，push rod，rocker arm，camshaft，timing gear，timing belt，tensioner，etc.,Part ReadingPassage One Valve and Valve Train,10,1.Engine crankshaft and connecting rod assembly is composed of ， ， and . 2
8、.The valve and valve train is composed of ，valve spring， ， ， ，rocker arm， ， ， ，tensioner，etc.,pistons,Part ReadingPassage OneExercises,piston rings,connecting rods,crankshafts,valve,valve guide,tappet,push rod,camshaft,timing gear,timing belt,Fill in the blanks below.,11,Part ReadingPassage Two Auto
9、mobile Cooling System,Components of water cooling system,1. louver 2. radiator 3. radiator cap 4. fan 5. pump 6. thermostat 7.water temperature gauge 8.water jacket of cylinder head 9.water distribution pipe 10.outlet valve,1.百叶窗 2. 散热器 3. 散热器盖 4.风扇 5.水泵 6.节温器 7.冷却液温度表 8.气缸盖水套 9.分水管 10.放水阀,12,An aut
10、omobiles cooling system is the collection of parts and substances（coolants）that work together to maintain the engines temperature at optimal levels. Comprising many different components such as water pump，coolant，a thermostat，etc.，the system enables smooth and efficient functioning of the engine at
11、the same time protecting it from damage.,Part ReadingPassage Two Automobile Cooling System,13,While its running，an automobiles engine generates enormous amounts of heat. Each combustion cycle entails thousands of controlled explosions taking place every minute inside the engine. If the automobile ra
12、ces on and the heat generated within isnt dissipated，it would cause the engine to self-destruct.,Part ReadingPassage Two Automobile Cooling System,14,Hence，it is imperative to concurrently remove the waste heat. While the waste heat is also dissipated through the intake of cool air and exit of hot e
13、xhaust gases，the engines cooling system is explicitly meant to keep the temperature within limits.,Part ReadingPassage Two Automobile Cooling System,15,The cooling system essentially comprises passages inside the engine block and heads，a pump to circulate the coolant，a thermostat to control the flow
14、 of the coolant，a radiator to cool the coolant and a radiator cap controls the pressure within the system.,Part ReadingPassage Two Automobile Cooling System,16,In order to achieve the cooling action，the system circulates the liquid coolant through passages in the engine block and heads. As it runs t
15、hrough，the coolant absorbs heat before returning to the radiator，to be cooled itself. Next，the cooled down coolant is recirculated and the cycle continues to maintain the engines temperature at the right levels.,Part ReadingPassage Two Automobile Cooling System,17,The cooling system essentially comp
16、rises passages inside the engine block and ，a to circulate the coolant，a to control the flow of the coolant，a to cool the coolant and a radiator cap controls the pressure within the system.,heads,Part ReadingPassage TwoExercises,pump,thermostat,radiator,Fill in the blanks below.,18,Translate the fol
17、lowing paragraph into Chinese. Comprising many different components such as water pump，coolant，a thermostat，etc.，the system enables smooth and efficient functioning of the engine at the same time protecting it from damage.,Part ReadingPassage Two Exercises,汽车冷却系统包括水泵、冷却液、恒温器等组件，能够使发动机平稳高效运行，同时使其免受损害
18、。,19,1,1. _,Lubricant Passage Way,Part ReadingPassage Three How the Lubrication System Works,20,Lubrication is employed to reduce friction by interposing a film between rubbing parts. The lubrication system must continuously replace the film. The lubricants commonly employed are refined from crude o
19、il after the fuels have been removed.,Part ReadingPassage Three How the Lubrication System Works,21,Their viscosities must be appropriate for each engine，and the oil must be suitable for the severity of the operating conditions. Oils are improved with additives that reduce oxidation，inhibit corrosio
20、n，and act as detergents to disperse deposit-forming gums and solid contaminants. Motor oils also include an antifoaming agent.,Part ReadingPassage Three How the Lubrication System Works,22,Various systems of numbers are used to designate oil viscosity；the lower the number，the lighter the body of the
21、 oil. Viscosity must be chosen to match the flow rate of oil through a part to the designed cooling requirements of the part.,Part ReadingPassage Three How the Lubrication System Works,23,If the oil is too thick it will not flow through the part fast enough to properly dissipate heat. Certain oils c
22、ontain additives that oppose their change in viscosity between winter and summer.,Part ReadingPassage Three How the Lubrication System Works,24,1,4. _,Gear oil pump（schematic）,Part ReadingPassage Three How the Lubrication System Works,1. _,Oil Cooler,2. _,Oil Filter,3. _,Lubrication Oil,25,Oil filte
23、rs，if regularly serviced，can remove solid contaminants from crankcase oil，but chemical reactions may form liquids that are corrosive and damaging. Depletion of the additives also limits the useful life of lubricating oils.,Part ReadingPassage Three How the Lubrication System Works,26,The lubrication
24、 system is fed by the oil pan that forms the lower enclosure of the engine. Oil is taken from the pan by a gear oil pump， and is passed through a oil strainer and delivered under pressure to a system of passages or channels drilled through the engine.,Part ReadingPassage Three How the Lubrication Sy
25、stem Works,27,Virtually all modern engines use full-flow type oil filters. Filtered oil is supplied under pressure to crankshaft and camshaft main bearings.,Part ReadingPassage Three How the Lubrication System Works,28,Adjacent crank throws are drilled to enable the oil to flow from the supply at th
26、e main bearings to the crank pins. Leaking oil from all of the crankshaft bearings is sprayed on the cylinder walls，cams，and up into the pistons to lubricate the piston pins.,Part ReadingPassage Three How the Lubrication System Works,29,Additional passages intersect the cam-follower openings and sup
27、ply oil to hydraulic valve lifters when used. A spring-loaded pressure-relief valve maintains the pressure at the proper level. Oil is important for both lubrication and cooling.,Part ReadingPassage Three How the Lubrication System Works,30,1. Lubrication is employed to reduce friction by interposin
28、g a film between rubbing parts. _ 2. Oil filters，if regularly serviced，can remove solid contaminants from crankcase oil，but chemical reactions may form liquids that are corrosive and damaging. _ _,6,Translate the following sentences into Chinese.,润滑的作用是通过油膜减少摩擦部件之间的摩擦。,机油滤清器，如果定期加以保养，可以从曲轴箱有效去除固体污染物
29、，但化学反应可能形成具有腐蚀性和破坏性的液体。,Part ReadingPassage Three Exercises,31,This light indicates the engine oil pressure，not the oil level. However，if your engine oil level is low，it will affect the oil pressure. The light should come on every time your ignition key is turned to ON or START and go out when the e
30、ngine starts.,Part Maintenance and repair How to Deal With Engine Oil Pressure Warning Light,32,If the light stays on or turns on while the engine is running，you have lost oil pressure and continued operation will cause severe engine damage.,Part Maintenance and repair How to Deal With Engine Oil Pr
31、essure Warning Light,33,If you lose oil pressure: （1）Pull off the road as soon as it is safely possible. （2）Shut off the engine immediately. If you do not stop the engine as soon as possible，severe engine damage could occur.,Part Maintenance and repair How to Deal With Engine Oil Pressure Warning Li
32、ght,34,If you lose oil pressure: （3）Check the engine oil level，following the instructions under Checking and Adding Engine Oil in the Owner Guide. To ensure an accurate reading，your car should be on level ground.,Part Maintenance and repair How to Deal With Engine Oil Pressure Warning Light,35,If yo
33、u lose oil pressure: （4）If the level is low，add only as much oil as necessary before you start the engine again. Do not overfill. Do not operate the engine again，if the light is on，regardless of the oil level.,Part Maintenance and repair How to Deal With Engine Oil Pressure Warning Light,36,Part Mai
34、ntenance and repair Exercises,Answer the following questions. If you lose oil pressure，what should we do？,37,The exhaust emissions of automotive engines contain a number of harmful pollutants. In order to minimize the amount of harmful pollutants being produced，manufactures have developed automotive
35、 emission controls.,Part Outward Bound Automobile exhaust gases,38,The following is a list of the harmful exhaust gases manufactures plan to reduce，which includes how the gases are formed and why they are dangerous.,Part Outward Bound Automobile exhaust gases,39,Carbon Monoxide （CO） Carbon Monoxide
36、consists of carbon and oxygen. This colorless， odorless，poisonous gas is the product of incomplete combustion. By weight，carbon monoxide accounts for the 47% of air pollution.,Part Outward Bound Automobile exhaust gases,40,Hydrocarbon（CH） Hydrocarbons consist of carbon and hydrogen. Hydrocarbons are
37、 emitted in an unburned form from equipment which uses a petroleum product as a source of fuel. Hydrocarbons are one of the key elements responsible for the production of photochemical smog.,Part Outward Bound Automobile exhaust gases,41,Oxides of Nitrogen（NOx） Oxides of nitrogen consist of nitrogen
38、 combined with varying amounts of oxygen. NOx are produced by heat and pressure during the combustion process. NOx are also a main component in smog.,Part Outward Bound Automobile exhaust gases,42,Photochemical Smog Photochemical smog，commonly referred to simply as smog，is a by-product of the combin
39、ation of HC and NOx. In the presence of sunlight these two elements form ozone（O3），nitrogen dioxide，and nitrogen nitrate; all of which cause respiratory problems. Nitrogen dioxide is a light brown colored gas which can affect visibility in the air corridors around major airport terminals and above h
40、ighways.,Part Outward Bound Automobile exhaust gases,43,Particulates Particulates are tiny particles of liquids and solids which are dispersed into the atmosphere during any burning process. Particulates are composed of carbon，ash，oil，grease，and metal oxides. Smoke，haze，and dust are types of air pol
41、lution which are readily visible and are known to complicate respiratory problems caused by smog.,Part Outward Bound Automobile exhaust gases,44,Sulfur Oxides（SOx） Sulfur oxides consist of various amounts of oxygen and sulfur. Sulfur oxides result from the burning of lower grades of fossil fuels，such as coal or oil.,Part Outward Bound Automobile exhaust gases,45,Translate the words or phrases in the following figure into Chinese.,Part Outward Bound Exercises,46,Thank you!,Automobile English,