汽车专业英语2Internalcombustionengine

1、汽车专业英语汽车专业英语 Specialty English for Automobile刘永刚刘永刚E-mail: Tel:hapter 2 Internal combustion engine 2.1 Principle of Operation Energy Power Chemical energy Burn / combustion Combustion chamber Internal (external) combustion engine Cylinder Heat engine Mechanical pistonInlet valvepistonco

2、nnecting rodTDCBDCExhaust valvecrankEngine TermsTDC（Top Dead Center）: the position of the crank and piston when the piston is farthest away from the crankshaft.BDC（Bottom Dead Center）: the position of the crank and piston when the piston is nearest away from the crankshaft.2.1.2 Engine terms 缸径缸径bor

3、estrokeTDCBDCClearancevolumeSweptvolumeClearance volume（余隙余隙/燃烧室容积）燃烧室容积）: : the volume of space above the piston when it is at TDC.Engine capacity（排量）（排量）: : this is the swept volume of all cylinders.Compression ratio（压缩比）（压缩比）: :(swept vol + clearance vol) /(clearance vol)活塞活塞行程行程Swept volume（有效（有

4、效/ /工工作容积）作容积）: :the volume between TDC and BDC.TDCBDCStrokeBoreSwept volumeEngine capacityClearance volumeCompression ratio Two-stroke: a power stroke every revolution of the crank Four-stroke: a power stroke every other revolution of the crank 每隔一个每隔一个 Top Dead Center Bottom Dead Center Stroke Bor

5、e Swept volume Engine capacity Clearance volume Compression ratio Two-stroke/Four-stroke revolution2.1.3 The four-stroke spark-ignition engine cycle1. Intake/Induction stroke 进气行程进气行程2. Compression stroke 压缩行程压缩行程3. Power stroke 作功行程作功行程4. Exhaust stroke 排气行程排气行程ward(s) 后缀后缀 表示方向表示方向2.1.4 Engine ove

6、rall mechanics Crankshaft and Connecting rods system 曲柄连杆机构曲柄连杆机构 Valve system 配气机构配气机构 Fuel system 供给系供给系 Intake system 进气系统进气系统 Cooling system 冷却系冷却系 Ignition system 点火系点火系 Starting system 起动系起动系 Lubrication system 润滑系润滑系 Exhaust system 排气系统排气系统2.2 Engine block and cylinder head发动机缸体是发动机的基本骨架，发动机其

7、余的零件或安装发动机缸体是发动机的基本骨架，发动机其余的零件或安装在缸体内部，或固定在缸体上。缸体里有气缸、水套和油道，在缸体内部，或固定在缸体上。缸体里有气缸、水套和油道，曲轴也固定在缸体底部。除了顶置凸轮轴发动机以外，凸轮曲轴也固定在缸体底部。除了顶置凸轮轴发动机以外，凸轮轴都固定在缸体内部。大多数汽车上，缸体采用灰铸铁或者轴都固定在缸体内部。大多数汽车上，缸体采用灰铸铁或者灰铸铁和其他金属（例如镍或铬）的合金铸造而成。灰铸铁和其他金属（例如镍或铬）的合金铸造而成。The engine block is the basic frame of the engine. All other en

8、gine parts either fit inside it or fasten to it. It holds the cylinders, water jackets, and oil galleries. The engine block also holds the crankshaft, which fastens to the bottom of the block. The camshaft also fits inside the block, except on overhead-cam engines (OHC). In most cars, this block is

9、made of gray iron, or an alloy (mixture) of gray iron and other metals, such as nickel or chromium. Engine blocks are castings.Be made of / manufactured withWear：穿戴，磨损：穿戴，磨损Line with: 布满；布满；给给加加The path to the house is lined with bushes.通向那所房子的小径长满了灌木丛。通向那所房子的小径长满了灌木丛。The coat is lined with silk.这件外

10、套用绸子作衬里。这件外套用绸子作衬里。Cylinder sleeves 气缸套气缸套Cylinder sleeves are used in engine blocks to provide a hard wearing material for pistons and piston rings. The block can be made of one kind of iron that is light and easy to cast while the sleeves uses another that is better able to stand up wear and tear.

11、 There are two main types of sleeves: dry and wet. 发动机缸体中的气缸套为活塞和活塞环提供一种坚发动机缸体中的气缸套为活塞和活塞环提供一种坚硬耐磨的材料。缸体可以采用较轻且易铸造的铁，硬耐磨的材料。缸体可以采用较轻且易铸造的铁，而气缸套采用更耐磨和耐冲击的材料。气缸套分为而气缸套采用更耐磨和耐冲击的材料。气缸套分为两种：干式和湿式。两种：干式和湿式。2.2.2 Cylinder sleeves2.2.3 Cylinder headThe cylinder head fastens to the top of the block, just as

12、 a roof fits over a house. The underside forms the combustion chamber with the top of the piston. In-line engines of light vehicles have just one cylinder head for all cylinders; larger in-line engines can have two or more. 气缸盖固定在气缸体的顶部，就像房子的房顶一样。气缸盖固定在气缸体的顶部，就像房子的房顶一样。气缸盖底部与活塞头部之间的空间形成了燃烧室。气缸盖底部与活塞

13、头部之间的空间形成了燃烧室。轻型汽车的直列式发动机采用一个气缸盖，较大的轻型汽车的直列式发动机采用一个气缸盖，较大的直列式发动机采用两个或多个气缸盖。直列式发动机采用两个或多个气缸盖。in-line 直列式直列式V型型Hemi 半球形半球形Wedge 楔形楔形Basin 盆形盆形Flat enginePancake engine 对置式对置式arrangementCylinder headIn-line enginePetrol 英英gasoline 美美Combustion chamberGasketSandwichAsbestos 石棉石棉Copper 铜铜Oil pan or sump

14、油底壳油底壳 / 集油槽集油槽 油底壳油底壳Oil panCrankcaseOil pumpLubricating systemCirculationThe oil pump in the lubricating system draws oil from the oil pan and sends it to all working parts in the engine. The oil drains off and runs down into the pan. Thus, there is constant circulation of oil between the pan and

15、the working pats of the engine. 润滑系的机油泵从油底壳抽出机油润滑系的机油泵从油底壳抽出机油，并把机油输送给发动机的所有工，并把机油输送给发动机的所有工作部件。机油从油底壳流进流出。作部件。机油从油底壳流进流出。因而在油底壳和发动机的工作部件因而在油底壳和发动机的工作部件之间就有机油定向循环流动。之间就有机油定向循环流动。Oil Pan / Sump 油底壳油底壳Oil PanComponents of a typical, four stroke cycle, D(dual)OHC piston engine. (E) Exhaust camshaft,(I)

16、 Intake camshaft, (S) Spark plug, (V) Valves, (P) Piston, (R) Connecting rod, (C) Crankshaft,(W) Water jacket for coolant flow.cylinder headhead coverwater jacketoil galleryoil pangasketcylindercylinder sleeveengine blockcrankcaseEngine block and Cylinder head 曲轴箱曲轴箱气缸盖罩气缸盖罩气缸气缸气缸套气缸套气缸体气缸体油底壳油底壳气缸盖

17、气缸盖衬垫衬垫水套水套油道油道Crankshaft 曲轴曲轴Piston ring 活塞环活塞环Piston (crownskirt)活塞（头部裙部）活塞（头部裙部）Piston pin活塞销活塞销Connecting rod连连 杆杆Big-end 连杆大头连杆大头Small-end 连杆小头连杆小头Cap 连杆盖连杆盖Shell bearing轴轴 瓦瓦Main bearing journal主轴颈主轴颈Connecting rod journal 连杆轴径连杆轴径Flywheel 飞轮飞轮2.3 Piston, Connecting rod and CrankshaftThe pisto

18、n is an important part of a four-stroke cycle engine. Most pistons are made from cast aluminum. The piston, through the connecting rod, transfers to the crankshaft the force created by the burning fuel mixture. This force turns the crankshaft. Thin, circular, steel bands fit into grooves around pist

19、on to seal the bottom of the combustion chamber. These bands are called piston rings. The grooves into which they fit are called ring grooves. A piston pin fits into a round hole in the piston. The piston pin joins the piston to the connecting rod. The thick part of the piston that holds the piston

20、pin is the pin boss.大多数活塞由铝铸造而成。通过连杆大多数活塞由铝铸造而成。通过连杆的作用，活塞把可燃混合气燃烧产生的作用，活塞把可燃混合气燃烧产生的力传递给曲轴，带动曲轴旋转。的力传递给曲轴，带动曲轴旋转。Piston AssemblyFlatConcaveDomeRecessedIn diesel engines, the combustion chamber may be formed totally or in part in the piston crown, depending on method of injection. 柴油机发动机根据喷柴油机发动机根据喷

21、油方法不同，活塞头油方法不同，活塞头部可以形成全部燃烧部可以形成全部燃烧室，也可以是燃烧室室，也可以是燃烧室的一部分的一部分PistonCompression ring: 气环气环 压缩环压缩环 压环压环Oil ring： 油环油环Piston ringsGas RingsOil RingsThe connecting rod is made of forged high-strength steel. It transmits force and motion from the piston to the crankpin on the crankshaft. The connecting

22、rod little end is connected to the piston pin. A bush made from a soft metal, such as bronze, is used for this joint. The lower end of the connecting rod fit the crankshaft journal. This is called the big end. 连杆采用高强度锻造钢。连杆将活塞的力连杆采用高强度锻造钢。连杆将活塞的力和运动传递给曲轴上的曲柄销。连杆小头和运动传递给曲轴上的曲柄销。连杆小头与活塞销连接，连接处有像与活塞销连接

23、，连接处有像青铜青铜这样软金这样软金属制成的属制成的衬套衬套，连杆下端连接在，连杆下端连接在曲柄轴径曲柄轴径上，称为连杆大头。上，称为连杆大头。2.3.3 connecting rodThe piston is an important part of a four-stroke cycle engine. Most pistons are made from cast aluminum. The piston, through the connecting rod, transfers to the crankshaft the force created by the burning fu

24、el mixture. This force turns the crankshaft. Thin, circular, steel bands fit into grooves around piston to seal the bottom of the combustion chamber. These bands are called piston rings. The grooves into which they fit are called ring grooves. A piston pin fits into a round hole in the piston. The p

25、iston pin joins the piston to the connecting rod. The thick part of the piston that holds the piston pin is the pin boss.2.3.4 crankshaftConjunction: 连接，同时发生连接，同时发生a conjunction of favourable political and economic circumstancesIn conjunction with：和：和一起一起Reciprocating: 往复往复bearing journal: 轴颈轴颈Alloy

26、: n/vt 合金，合金，mix (metals) to make an alloythrow：半径，行程：半径，行程TDC、BDC、Vice versa2.3.5 cylinder numbering and firing orderImpluse/pulse 脉冲脉冲Flow 流程流程Space ：把：把.分隔开分隔开, 排开排开, 按一定距离安排开按一定距离安排开 space out the lampposts 30 meters apartInterval 间隔间隔Diagram: 简图，示意图简图，示意图Firing order: 点火顺序点火顺序2.5 Valve systemTh

27、e valve system is made up of those parts needed to open and close the valves at just the right time.To coordinate the four-stroke cycle, a group of parts called the valve trains opens and closed the valves (moves them down and up, respectively). These valve movements must take place at exactly the r

28、ight moments. The opening of each valve is controlled by a camshaft.The cam is an egg-shaped piece of metal on a shaft that rotates in coordination with the crankshaft. The metal shaft, called the camshaft, typically has individual cams for each valve in the engine. As the camshaft rotates, the lobe

29、, or high spot of the cam, pushes against parts connected to the stem of the valve. This action forces the valve to move downward. This action could open an inlet valve for an intake stroke, or open an exhaust valve for an exhaust stroke.凸轮是一个蛋形的金属块，它安装在同曲凸轮是一个蛋形的金属块，它安装在同曲轴协调运转的一根金属轴上，该轴称为凸轴协调运转的一根

30、金属轴上，该轴称为凸轮轴，其上有同发动机每一个气门对应的轮轴，其上有同发动机每一个气门对应的凸轮。当凸轮轴旋转时，凸轮的最高点，凸轮。当凸轮轴旋转时，凸轮的最高点，也就是凸圆，推动连接气门杆的部件，使也就是凸圆，推动连接气门杆的部件，使得气门向下运动，在进气冲程打开进气门得气门向下运动，在进气冲程打开进气门，在排气冲程打开排气门。，在排气冲程打开排气门。Valves in modern car engines are located in the cylinder head at the top of the engine. This is known as an overhead valve

31、 (OHV) configuration. In addition, when the camshaft is located over the cylinder head, the arrangement is known as an overhead camshaft (OHC) design. Some high performance engines have two separate camshafts, one for each set of inlet and exhaust valves. These engines are known as dual overhead-cam

32、shaft (DOHC) engine.In this arrangement, the cam lobes push against round metal cylinders called cam follower. As the lobe of the cam comes up under the cam follower, it pushes the cam follower upward (away from the camshaft). The cam follower rides against a push rod, which pushes against a rocker

33、arm. The rocker arm pivots on a shaft through its center. As one side of the rocker arm moves up, the other side moves down, just like a seesaw. The downward-moving side of the rocker arm pushes on the valve stem to open the valve.Push-rod valve trainRocker-arm（摇臂）（摇臂）CamshaftTappet(Cam follower)Pus

34、h-rodValve clearancesValve SpringValve stemValve seat（气门座）（气门座）Valve headPistonRocker-shaft2.5.2 Valve clearanceWhen the engine runs in compression stroke and power stroke, the valves must close tightly on their seats to produce a gas-tight seal and thus prevent the gases escaping from the combustio

35、n chamber. If the valves do not close fully the engine will not develop full power. Also the valve heads will be liable to be burnt by the passing hot gases, and there is the likelihood of the piston crown touching an open valve, which can seriously damage the engine.当发动机处于压缩行程或做功行程时，气门必须紧闭在气门座当发动机处

36、于压缩行程或做功行程时，气门必须紧闭在气门座上，提供很好的密封性，从而防止气体从燃烧室中溢出。如果上，提供很好的密封性，从而防止气体从燃烧室中溢出。如果气门不能完全关闭，则发动机不能产生最大的功率。另外气门气门不能完全关闭，则发动机不能产生最大的功率。另外气门头容易被流经的高温气体烧蚀，有可能导致活塞头部冲击打开头容易被流经的高温气体烧蚀，有可能导致活塞头部冲击打开的气门，会严重破坏发动机。的气门，会严重破坏发动机。为保证气门能完全关闭，必须在气门工作机为保证气门能完全关闭，必须在气门工作机构中留有间隙。这就意味着气门传动机构和构中留有间隙。这就意味着气门传动机构和气门之间有足够远的距离，从而

37、保证气门能气门之间有足够远的距离，从而保证气门能够在弹簧的作用下紧闭气门座。但是如果气够在弹簧的作用下紧闭气门座。但是如果气门间隙过大，会产生轻微的金属敲打声。门间隙过大，会产生轻微的金属敲打声。So that the valves can close fully some clearance is needed in the operating mechanism. This means that the operating mechanism must be able to move sufficiently far enough away from the valve to allow

38、the valves to be fully closed against its seat by the valve spring. However, if the clearance is set too great this will cause a light metallic tapping noise. 2.5.3 valve timingThe time at which valves open and close (valve timing) and duration of valve opening is stated in degrees of crankshaft rot

39、ation. For example, the intake valve normally begins to open just before the piston has reached top dead center. The valve remains open as the piston travels down to BDC and even past BDC. This is intake valve duration. An example of this could be stated as follows: IO at 17oBTDC, IC at 51oABDC (or,

40、 intake opens 17obefore top dead center, intake closes 51o after bottom dead center). Intake valve duration in this case is 248o of crankshaft rotation.It is apparent from this description that the exhaust valve stays open for a short period of time during which the intake valve is also open. In oth

41、er words, the end of the exhaust stroke and the beginning of the intake stoke overlap for a short period of time. This is called valve overlap. Valve timing and valve overlap vary on different engines. 从上述描述显而易见，排气门开启时，有一小段时间，进气门也从上述描述显而易见，排气门开启时，有一小段时间，进气门也是开启的。换句话说，排气行程终了和进气行程初期有一短时间是开启的。换句话说，排气行程

42、终了和进气行程初期有一短时间的重叠，这就称之为气门重叠。不同的发动机具有不同的气门正的重叠，这就称之为气门重叠。不同的发动机具有不同的气门正时和气门重叠。时和气门重叠。The entire valve-train assembly can be viewed as a spring/mass system in which the conversion from stored to free energy causes forced vibration. Valve-train assemblies with overhead camshafts can be represented with

43、 sufficient accuracy by a 1-mass system ( (consisting of the moving mass, the valve-train assembly stiffness and corresponding damping) ). 整个气门传动机构可以被看做成一个弹簧整个气门传动机构可以被看做成一个弹簧/ /质量系统，其储质量系统，其储存的能量转换为自由能量时产生了受迫振动。顶置凸轮轴存的能量转换为自由能量时产生了受迫振动。顶置凸轮轴的气门传动总成可非常精确地用单质量系统（包含移动的的气门传动总成可非常精确地用单质量系统（包含移动的质量、气门机构总

44、成的刚度和相应的阻尼）表示。质量、气门机构总成的刚度和相应的阻尼）表示。2.5.4 cam design and control dynamics2.5.5 camshaft drive mechanismEach cam must revolve once during the four-stroke cycle to open a valve. A cycle, remember, corresponds with two revolutions of the crankshaft. Therefore, the camshaft must revolve at exactly haft

45、the speed of the crankshaft. This is accomplished with a 2:1 gear ratio. A gear connected to the camshaft has twice the number of teeth as a gear connected to the crankshaft.Belt driveCog-type belt 齿形带齿形带Reinforce：加强：加强Fiberglass：玻璃纤维：玻璃纤维Slotted：开槽：开槽Chain driveGear driveVariable valve timing In in

46、ternal combustion engines, variable valve timing, often abbreviated to VVT, is a generic term for an automobile piston engine technology. VVT allows the lift, duration or timing (in various combinations) of the intake and/or exhaust valves to be changed while the engine is in operation.The profile,

47、or position and shape of the cam lobes on the shaft, is optimized for a certain engine revolutions per minute (RPM), and this tradeoff normally limits low-end torque, or high-end power. VVT allows the cam timing to change, which results in greater efficiency and power, over a wider rev-range.通用、专业术语

48、；轮廓、型线；转速通用、专业术语；轮廓、型线；转速/分；分；低端扭矩；高端功率低端扭矩；高端功率At high engine speeds, an engine requires large amounts of air. However, the intake valves may close before all the air has been given a chance to flow in, reducing performance. On the other hand, if the cam keeps the valves open for longer periods of

49、time, as with a racing cam, problems start to occur at the lower engine speeds. This will cause unburnt fuel to exit the engine since the valves are still open. This leads to lower engine performance and increased emissions. For this reason, pure racing engines cannot idle at the low speeds (around

50、800rpm) expected of a road car, and idle speeds of 2000 rpm are not unusual.Pressure to meet environmental goals and fuel efficiency standards is forcing car manufacturers to turn to VVT as a solution. Most simple VVT systems advance or retard the timing of the intake or exhaust valves. Others (like

51、 Hondas VTEC) switch between two sets of cam lobes at a certain engine RPM. Furthermore Hondas I-VTEC can alter intake valve timing continuously.VTEC (Variable Valve Timing and Lift electronic Control) 可变气门配气相位和气门升程电子可变气门配气相位和气门升程电子控制系统控制系统 is a valvetrain system developed by Honda to improve the vo

52、lumetric efficiency of a four-stroke internal combustion engine. This system uses two camshaft profiles and electronically selects between the profiles. It was invented by Honda R&D engineer Ikuo Kajitani. VTEC was the first system of its kind, though other variable valve timing and lift control sys

53、tems have been produced by other manufacturers (MIVEC from Mitsubishi, VVTL-i from Toyota, VarioCam Plus from Porsche, VVL from Nissan, etc)VVT-i, or Variable Valve Timing with intelligence, is an automobile variable valve timing technology developed by Toyota, similar in performance to the BMWs VAN

54、OS.生词表生词表EngineStoke：inductionCompressionpoweremissionTop/bottom dead centerSwept volumeCompression ratioClearance volumeEngine capacityMechanicsMechanism meknizmBlockWater jacketCylinder sleeve (dry or wet)Cylinder headCombustion chamberGasketOil pan sumpPiston /- ring /- pinConnecting rodCrankshaf

55、tBearing journalReciprocateFiring orderFlywheelPiston crown / skirtDiagram 生词表生词表mountingAmplitudeRollPitchyawValve systemCamshaftOverheadHead Camshaft valve trainPush-rod valve trainCam followerPush rodRocker armValve seatValve clearanceValve timingIntake/ exhaust valveBelt / chain / gearTeeth (gea

56、r)Today, internal combustion engines in cars, trucks, motorcycles, aircraft, construction machinery and many others, most commonly use a four-stroke cycle. The four strokes refer to intake, compression, combustion (power), and exhaust strokes that occur during two crankshaft rotations per working cy

57、cle of the gasoline engine and diesel engine.The cycle begins at top dead center (TDC), when the piston is farthest away from the axis of the crankshaft. On the intake or induction stroke of the piston, the piston descends from the top of the cylinder, reducing the pressure inside the cylinder. A mi

58、xture of fuel and air is forced (by atmospheric or greater pressure) into the cylinder through the intake (inlet) port. The intake (inlet) valve (or valves) then close(s), and the compression stroke compresses the fuelair mixture.The airfuel mixture is then ignited near the end of the compression st

59、roke, usually by a spark plug (for a gasoline or Otto cycle engine) or by the heat and pressure of compression (for a Diesel cycle or compression ignition engine). The resulting pressure of burning gases pushes the piston through the power stroke. In the exhaust stroke, the piston pushes the product

60、s of combustion from the cylinder through an exhaust valve or valves. 汽车的动力源是发动机。发动机乃是将某一种形式的汽车的动力源是发动机。发动机乃是将某一种形式的能量转变为机械能的机器。将热能转变为机械能的发动能量转变为机械能的机器。将热能转变为机械能的发动机，称之为热力发动机，其中的热能是由燃料燃烧所产机，称之为热力发动机，其中的热能是由燃料燃烧所产生的。内燃机是热力发动机的一种，其特点是液体或气生的。内燃机是热力发动机的一种，其特点是液体或气体燃料和空气混合后直接输入机器内部燃烧而产生热能，体燃料和空气混合后直接输入机器