重庆大学车辆工程专业英语

Chapter 1 Automotive Basics (1) Today s average car contains more than 15,000 separate, individual parts that must work together. These parts can be grouped into four major categories: body, engine, chassis and electrical equipment 。P1 当今的车辆一般都由15000多个分散、独立且相互配合的零部件组成。这些零部件主要分为四类:车身、发动机、底盘和电气设备。 1.1 Body (2) The body is designed to keep passengers safe and comfortable. The body styling provides an attractive, colorful, modern appearance for the vehicle. P2车身的 设计 领导形象设计圆作业设计ao工艺污水处理厂设计附属工程施工组织设计清扫机器人结构设计 要保证乘客安全舒适。车身的款式使得汽车看起来漂亮迷人、色彩斑斓、时尚前卫。 1.2 Engine (3)The internal combustion engine is most common: this obtains its power by burning a liquid fuel inside the engine cylinder. There are two types of engine: gasoline and diesel . Both engines are called heat engines; the burning fuel generates heat which causes the gas inside the cylinder to increase its pressure and supply power to rotate a shaft connected to the transmission . P3内燃机是最常见的,其动力来自气缸里液体燃料的燃烧。发动机有汽油机和柴油机两种,都称为热机燃料燃烧产生热量,使得气缸内气体压力升高,从而提供动力,带动连接变速器的轴旋转. 1.3 Chassis 1.3.3Suspension (4) The purpose of the complete suspension system is to isolate the vehicle body from road shocks and vibrations, which will otherwise be transferred to the passengers and load. It must also keep the tires in contact with the road regardless of road surface. P5整个悬架系统的作用是隔离来自路的冲击和振动对车身的影响,防止它们传递给乘客和货物。另外不论路面如何,悬架系统都应该保持轮胎和路的接触。1.3.4 Braking (5) Drum brakes have a drum attached to the wheel hub, and braking occurs by means of brake shoes expanding against the inside of the drum. With disc brakes, a disc attached to the wheel hub is clenched between two brake pads. P6在鼓式制动器上,制动鼓和轮毂连接,制动蹄张开压紧制动鼓内侧从而产生制动。在盘式制动器上,连着轮毂的制动盘,被紧紧夹在两个制动块之间。 1.4Electrical system (6) The electrical system supplies electricity for the starter, ignition, lights and heater. The electricity level is maintained by a charging circuit. P8电器系统为起动机、点火系、照明和加热设备提供电流。电流的大小由充电电路来维持。Automotive Engineering English 、 Chapter 2 Internal Combustion Engine 2。1。2 Engine Terms 2) Linking the piston by a connecting rod to a crankshaft causes the gas to rotate the shaft through half a turn. The power stroke "uses up" the gas, so means must be provided to expel the burnt gas and recharge the cylinder with a fresh petrol-air mixture: this control of gas movement is the duty of the valves; (Page 10) 活塞通过连杆和轴连接,使得气体带动轴旋转半圈。作功冲程耗尽了所有的气体,这样就必须采取相应的 措施 《全国民用建筑工程设计技术措施》规划•建筑•景观全国民用建筑工程设计技术措施》规划•建筑•景观软件质量保证措施下载工地伤害及预防措施下载关于贯彻落实的具体措施 排出废气以及向气缸内再充入新鲜的可燃混合气:气体的运动由气门来控。 2.2.1 Engine Block 1) The engine block is the basic frame of the engine. All other engine 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. (Page 13) 缸体是发动机的基体。发动机其它的部件都安装或固定在缸体上,包括气缸、水套和油道,以及固定在缸体底部的曲轴等。 2.2.2Cylinder Sleeves 2) 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. There are two main types of sleeves: dry and wet. (Page 10) 缸体中的气缸套为活塞和活塞环提供了一种坚硬耐磨的 材料 关于××同志的政审材料调查表环保先进个人材料国家普通话测试材料农民专业合作社注销四查四问剖析材料 。缸体可以采用某种重量轻且易铸造的铁来制造,而缸套使用的却是另一种更加耐磨损的材料成。主要有两种类型的气缸套:干缸套和湿缸套。 2.2.3 Cylinder Head 3) The cylinder head fastens to the top of the block, just as 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. (Page 14) 气缸盖安装在缸体的顶部,就像安在房子上的屋顶一样。缸盖的下方和活塞顶部形成燃烧室。轻型车上 使用的直列发动机,所有气缸仅有一个气缸盖,较大的直列发动机有两个或更多缸盖。 2.2.5Oil Pan 4) The 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 the working pats of the engine. (Page 15) 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之间就有机油定向循环流动。 2.3.2 Piston Assembly (Page 17) 1) 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.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力传递给曲轴,带动曲轴旋转。 1. Piston 2) In diesel engines, the combustion chamber may be formed totally or in part in the piston crown, depending on method of injection. (Page 18) 柴油机发动机根据喷油方法不同,活塞头部可以形成全部燃烧室,也可以是燃烧室的一部分. 2.Piston Rings In modern engines, each piston has three rings. (Piston in older engines Gas Rings sometimes had four rings, or even five.) The inside surface of the ring fits in the groove on the piston. The ring's outside surface presses against the cylinder walls. 在新型发动机上,每个活塞有三个活塞环。(在老式发动机上,每个活塞有四个甚至五个活塞环)环的内侧装在活塞的环槽里,环的外表面紧压在气缸壁上。 2.3.2Connecting rod 4) The connecting 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. (Page 19) 连杆小头与活塞销连接,连接处有像青铜这样软金属制成的衬套,连杆下端连接在曲柄轴径上,称为连杆大头。5) N.B. No.4 piston is always performing the companion stroke to No.1: when the inlet valve in No.4 cylinder is fully open, No.1 cylinder inlet valve is fully closed --- this feature is useful to remember when checking valve clearances. (Page 20) 注意4号活塞和1号活塞总是成对运行:1号气缸进气门全闭时,4号气缸进气门全开这个特点在检查气门间隙时是很有用的。6) As each cylinder fires, it causes the crank throw to speed up. The inertia of the rest of shaft cause it to stay slightly behind, resulting in a twisting action on the crankshaft. (Page 20) 当一气缸点火时,使拐的转速提高,而轴的其它部分由于惯性作用,有所滞后,从而导致曲轴扭转。 2.5: valve system 1、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, 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. (p26)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轴上,该轴称为轮轴,其上有同发动机每一个气门对应的凸轮。当轮轴旋转时,轮的最高点,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,在排气冲程打开排气门。2、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 arm. The rocker armpivots 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. (p27)在这种 方案 气瓶 现场处置方案 .pdf气瓶 现场处置方案 .doc见习基地管理方案.doc关于群访事件的化解方案建筑工地扬尘治理专项方案下载 中,轮圆推动圆形的金属筒,也就是挺柱。轮圆运动到挺柱下方时,推动挺柱远离轮轴向上运动。挺柱带着推杆,推杆推动摇臂,摇臂绕摇臂轴的中心转动。摇臂的一端升起,另一端就落下,这类似于跷跷板。摇臂向下运动的一端推动气门杆打开气门。3、When 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 combustion 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. (p28)当发动机在压缩冲程和作功冲程作时,气门必须紧贴在气门座上,形成良好的气密性以防止燃烧室漏气。如果气门关闭不严,发动机就不能发挥出全部的功率。而且气门头部容易被经过的高温气体烧蚀,活塞顶部也可能会碰到气门使发动机严重损坏。4、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 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. (p28)所以在气门传动机构中要预留一些间隙使气门得以完全关闭。这就是说,气门传动机构运动要与气门有一个充分远的距离,使得气门在气门弹簧作用下紧闭气门座。可是如果间隙过大,会引起轻微的金属敲打声。 5、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 other 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. (p28)由上显而易见,排气门在进气门打开的一小段时间内也打开着。换句话说,排气冲程终了和进气冲程初期有一小段时间的重叠,这称为气门重叠。不同的发动机,其配气正时和气门重叠是不一样的。 6、Opening the intake valve before TDC and closing it after BDC increases the fill of air-fuel mixture in the cylinder. Opening the intake valve early helps overcome the static inertia of the air-fuel mixture at the beginning of the intake stroke, while leaving the intake valve open after BDC takes advantage of the kinetic inertia of the moving air-fuel mixture. This increases volumetric efficiency. (p28)在上止点前打开进气门和在下止点后关闭进气门可增加气缸内可燃混气的进气量提前打开进气门有助于克服进气冲程初期可燃混气的静惯性,同时在下止点后保持进气门打开,可充分利用可燃混气运动时的惯性,这可增加容积效率。 7、The entire valve-train assembly can be viewed as a spring/mass system in which the conversion from stored to ree energy causes forced vibration. Valve-train assemblies with overhead camshafts can be represented with sufficient accuracy by a 1-mass system (consisting of the moving mass, the valve-train assembly stiffness and corresponding damping). (p29)整个气门机构总成可看成一个弹簧-质量系统,其储存的能量转化为自由能量时会引起受迫振动。带有顶置凸轮轴的气门机构可非常精确地用单质量系统来表示,由运动质量、气门机构的刚度和相应的阻尼组成。 8、Each 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 half 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. (p29)在一个四冲程的循环里,每个凸轮转动一次来打开一个气门。在一个循环里曲轴是转动两圈的。因此,凸轮轴必须以曲轴转速的一半旋转,这是由2:1的传动比来实现的。连接凸轮轴的齿轮齿数是连接曲轴的齿轮齿数的2倍。 9、An electronic valve control system replaces the mechanical camshaft, controlling each valve with actuators for independent valve timing. The EVC system controls the opening and closing time and lift amount of each intake and exhaust valve with independent actuators on each valve. Changing from a mechanical driven valve into independently controlled actuator valve provides a huge amount of flexibility in engine control strategy. (p30)电控气门控制系统代替了机械式的凸轮轴,用执行器控制每个气门独立的进、排气正时。EVC通过每个气门上的独立执行器控制进气门和排气门的开启、关闭时间以及升程量。由机械式驱动气门到独立控制执行器气门的转变,极大的增加了发动机控制策略的灵活性。 2.6 Gasoline Fuel System 1) (P.33) Gasoline must vaporize easily. This characteristic, called volatility is important. However, it must not vaporize too easily, or it will turn to vapor inside the fuel tank or fuel lines. Inside the fuel line, fuel vapor may block the flow of liquid gasoline. This is called vapor lock. V apor lock is common in fuel lines where the inlet side of the pump is exposed to high temperatures. 油应易于蒸发,这个重要的特性称为挥发性。但是汽油也不能挥发得过快,不然它会在油箱或油管里转变为蒸气。在油管中油蒸气会阻碍液态油的流动,这称为气阻。汽油泵的入口处易受高温,就经常出现气阻。2) (P.33) Increasing the pressure of the fuel mixture in the combustion chamber before ignition helps to increase the power of an engine. This is done by compressing the fuel mixture to a smaller volume. Higher compression ratios not only boost power but also give more efficient power. But as the compression ratio goes up, knocking tendency increases. 在点火前增加燃烧室内可燃混合气的压力有助于提高发动机的功率,这是通过把可燃混合气压缩到一个极小的体积来实现的。高的压缩比不仅可以增加功率,而且会带来更多的有功率。但随着压缩比的增加,爆震的可能性也会增加。3) (P.34) Two primary standard reference fuels, normal heptane and iso-octane arbitrarily assigned 0 and 100 octane number, respectively, are then blended to produce the same knock intensity as the test sample. The percentage of iso- octane in blend is considered the octane number of the test sample. Thus, if the matching reference blend is made up of 15% n-heptane and 85% isooctane, the test sample is rated 85 motor or research octane number, according to the test method used. 两种 标准 excel标准偏差excel标准偏差函数exl标准差函数国标检验抽样标准表免费下载红头文件格式标准下载 参考燃料正庚烷和异辛烷分别被定义成辛烷值为0和辛烷值为100,将它们混合产生与实验样本相等敲缸强度的爆震。混合物中异辛烷的百分比就认为是实验样本的辛烷值。这样,依照实验方法,如果匹配的参考混合物由15%的正庚烷和85%异辛烷组成,那么按照所用的实验方法,对比实验样本的辛烷值就是85 4) Fuel pump: Most cars today have a mechanical fuel pump. This pumps fuel out of the tank and through the fuel lines to the carburetor or injection system. In most cars, the pump is mounted on the engine block. Some cars have an electric fuel pump. This pump mounts in the fuel tank with the fuel pickup and the fuel-gauge-sending unit. (P.37) 当前大多数车采用机械油泵,油泵从油箱抽出油,通过油管送到化油器或喷射系统。大部分车的油泵安装在缸体上。一些车采用电动油泵,油泵安装在油箱上,附带有油量传感器和燃油表油量传送装置。5) Fuel pump: The rotation of the lobe moves a rocker arm in the pump. Inside the pump, a flexible diaphragm connects to the rocker arm though a diaphragm spring, pull rod and link. (P.37) 凸圆旋转带动油泵中的摇臂运动。油泵中可变形膜的泵膜通过膜回位弹簧和膜片拉杆与摇臂相连。6) (P.37) A carburetor delivers fuel in proportion to the amount of air flowing through it. As you press on the accelerator pedal, the throttle valve opens wider to draw more air through the carburetor The carburetor provides richer or leaner mixtures, depending on a number of factors: engine speed, load, temperature, and throttle position. To meet complicated demands, a carburetor is a highly intricate device, with many internal passages and parts. 化油器输送的燃油与流经化油器的空气量成一定比例。踩下加速踏板,节气门开度变大,化油器吸入的空气增加。化油器可提供较浓或较稀的混合气,这取决于发动机转速、负荷、温度和油门开度等因素。为满足复杂的要求,化油器的结构也很复杂,其上有很多内部通道和部件。 7) (P.37) Venturi : An automobile carburetor is designed with a venturi chamber. The venturi is simply a narrowed portion in the air passage. Air moving through the throat of the carburetor speeds up as it travels through this narrowed passageway. The increased air speed through the venturi creates a low-pressure area at the opening of the fuel nozzle. Atmospheric pressure pushes down on a fuel reservoir within the carburetor known as the float chamber. Fuel is forced through a tube that extends into the low-pressure area of the venturi. Thus, fuel sprays through the end of the tube into the air stream. 化油器设计成带有喉管的形式,喉管只是空气通道中一段狭窄的部分。空气流过化油器的喉管时速度增加,在喷嘴的开口处形成低压区。大气压力作用在储存汽油的浮子室上。燃油便被压入伸向喉管低压区的喷管里。这样燃油从喷管末端喷射到气流中。8) (P.38) carburetor: The float chamber is a reservoir for storing and supplying fuel to the carburetor. As the engineuses fuel, the float chamber replenishes it automaticaThlely. float chamber works on the same basic principle as the holding tank in a flushing toilet. A float rests on top of the fuel in the reservoir. As fuel is used, the float level drops. When the float drops, a needle valve is opened. 浮子室用于储存燃油以及向化油器提供燃油。发动机消耗燃油时,浮子室会自动进行补充。浮子室和抽水马桶储水箱的基本工作原理是相同的。浮子停留在浮子室的油面上。消耗燃油时,浮子下落,针阀打开。 9) (P.38) The pressure differential between the float chamber and the venturi causes fuel to flow. However, to maintain the proper air-fuel ratio, the carburetor must provide just the right amount of fuel. To do so, the main discharge tube has a small hole (called a jet or main jet). This allows a precise amount of fuel to enter the airstream. In most cases, this small hole is in the float chamber at the end of the main discharge tube. There, its small size limits fuel flow. 浮子室和喉管之间的压力差引燃油的流动。然而,为维持合适的空燃比,化油器必须提供适量的燃油。为此,在主喷管上有一个小孔,称作量孔或主量孔,它使得精确数量的燃油进入到气流中。量孔一般在主喷管末端的浮子室里,控制着燃油的流量。 10)(P.38) The throttle mechanism controls the flow of the air- fuel mixture. The throttle has several parts, including the throttle shaft and the throttle plate. By opening and closing, the throttle plate controls the flow of the air-fuel mixture into the engine. More air flows in as the plate opens; less air flows in as the plate closes. 节气门机构控制着可燃混合气的流量,包括节气门轴和节气门等部件。节气门的开启和关闭控制着进入发动机的可燃混合气流量。节气门开启,空气流量增加;节气门关闭,空气流量减少。 2.6.6 Gasoline direct injection (GDI) Conventional gasoline engines are designed to use an electronic fuel injection system, replacing the traditional mechanical carburetion system. Multi-point injection (MPI), where the fuel is injected through each intake port, is currently one of the most wider used systems. Although MPI provides a drastic improvement in response and combustion quality, it is still limited due to fuel and air mixing prior to entering cylinder. (p42) 常规的汽油发动机用电控燃油喷射系统代替传统的机械化油系统。通过每个进口喷射燃料的多点喷射(MPI )系统是现在最广泛使用的系统之一。尽管MPI系统在燃料反应及燃烧质量上有很大的改善,但是进入缸前的空燃混合气仍然限制了它的发展。 2.7 Diesel Engine 1) (P.46) Diesel engine gets this name from the pioneer work done by Dr Rudolf Diesel. The diesel is used for the majority of heavy vehicles and the excellent fuel economy makes it an attractive alternative to the petrol engine for light commercial vehicles, delivery vans and taxis. 柴油发动机的名称来源于Rudolf Diesel博士所完成的开拓性工作。大多数重型车辆使用柴油,优良的燃油经济性使得柴油机成为具有吸引力的替代品,来代替轻型商用车、厢式运输货车和出租车上汽油机。 2) (P.48) As diesel engines always deal with interior mixture formation only a heterogeneous mixture is obtained in the combustion chamber. In heterogeneous mixtures the excess-air factor λextends from pure air in the spray periphery (l= infinite) to pure fuel in the spray core (l= 0). 由于油机总是只在气缸内部形成可燃混合气,在燃烧室内就会得到不均匀的混合气。不均匀混合气的过量空气系数范围从喷射外围纯空气的无穷大到喷射中心纯燃的零。3) (P48) The fuel-injection system on a diesel engine must do a number of important things. First, it must meter the correct amount of fuel to run the engine at the speed and load demanded by the driver.Then it must deliver the metered fuel equally to all cylinders, at exactly the right time. Next, it must inject the fuel at the correct rate and spray pattern for the best burning in the combustion chamber. (P48) 柴油机的燃油喷射系统要完成许多重要的工作。首先,它必须定量供应准确数量的燃油,使发动机在驾驶员所要求的转速和负荷条件下运行。然后,它必须准确地在恰当的时刻把定量供应的燃油平均分配给每一个气缸。为使燃烧室中燃燃烧效果最好,它又必须以准确的速度和喷射方式喷油。4) With the injector pump on the low part (base circle) of the camshaft, the inlet and spill ports are open. This allows fuel to flow at 268 kPa into the venturi on top of the plunger.As the camshaft turns, the lobe moves the plunger upward. This raised the fuel pressure, forcing fuel through the delivery valve and on through the lines. The lobe continues to move the plunger upward to a point where the spiral groove in the plunger uncovers the spill port in the venturi. At this point, fuel above the plunger drains through the spill port. This is the end of injection. (P.49) 当喷油泵处于凸轮轴基圆时,进油孔和回油孔都打开,柴油以268KPa的压力流入柱塞上方的柱塞腔。凸轮轴旋转时,凸圆使柱塞向上移动,油压增加,油从出油阀流出送入高压油管。凸圆继续推动柱塞向上移动,直到柱塞运动到螺旋槽打开柱塞腔上的回油孔时的位置,此时,柱塞上方的柴油从回油孔流出,喷油过程结束。 5) At equilibrium, the control rod assumes a position for a supply of fuel which corresponds to engine power at, that operating point. If engine speed drops as a result of increased load, for example, the centrifugal force is also reduced and the governor springs move the flyweights, and thus the control rod, in the direction of increased fuel delivery until equilibrium is again established. (p52) 平衡时,控制杆的供油位置由该工况点发动机相应功率决定.例如,如果由于负载增加,发动机速度下降,飞块的离心力会随之下降.此时,调速器弹簧压动飞块,带动控制杆向加油方向运动直至平衡重新建立. 6) (P52) All previous injection systems have one disadvantage in common : the pressure generation and the supply of the injection quantity are not mutually independent. The result is that the injection pressure increases with the engine speed and also increases during injection (approximately linearly). Consequently, smaller injection quantities are injected with low pressure. The peak pressure is almost twice as high as the average injection pressure, which is responsible for the quality of the fuel swirl in the combustion chamber. 前述所有的喷射系统都有一个共同的缺点:油压的产生和喷射的供油量不是相互独立的,这样喷油压力随转速而增加,同样在喷油期间也几乎呈线性增加。因此,少量柴油会以低压喷射。最高喷油压力几乎是平均喷油压力的两倍,这会影响燃烧室内柴油漩涡的质量 7) (P53) A pressure accumulator is supplied with fuel by a high-pressure pump (Common Rail). The pressure in the common rail is measured with a pressure sensor and settled to a constant value by a pressure-control valve in the high-pressure pump. Depending on the requirements of combustion, the pressure in the rail can be maintained, largely independent of the engine speed, at a constant value in the range between 15~ 140MPa. 高压油泵(共轨管)向积压器供油。压力传感器测量共轨管的压力,高压油泵的油压控阀将压力控为一个常数。根据燃烧的要求,共轨管内的油压维持在15~140MPa 范围内的一个固定值,这基本上与发动机转速无关。 8) (P54) At exhaust-gas turbo-charging, the exhaust-gas energy which would have been lost is used to drive a turbine. This turbine drives a compressor which aspirates the combustion air and supplies it pre-compressed to the engine. In this way, more fuel can be supplied to the larger air mass and the engine power is increased. A positive effect is also exerted on the combustion process. 在废气涡轮增压中,原本要丧失的废气能量用来驱动涡轮,涡轮驱动压缩机,压缩机吸入助燃空气,预压缩后送给发动机。这样,空气量多,供油也多,发动机功率就会增加,对燃烧过程也会带来积极作用。 2.8Emission Control 1) Thermostat circulation (P58) When the engine is cool, the thermostat remains closed so that coolant cannot circulate through the radiator. Instead, coolant is recirculated within the engine block and cylinder head until the coolant reaches a predetermined temperature. At that temperature a wax-like pellet expands inside the thermostat to open it and allow the coolant to flow. Today, most original-equipment thermostats open at approximately 85oC to 90oC. In hotter climates, a “cooler” thermostat may be used to help avoid overheating. 当发动机温度较低时,节温器保持关闭,冷却水不能流通散热器进行循环,而是在发动机缸体和缸盖之间循环流动,一直到冷却水达到预定的温度为止。在该温度下,节温器中的蜡芯膨胀,从而打开节温器,使得循环水流经节温器。目前,多数原装节温器的开启温度大约在85~90oC。气温较高时,可采用低温节温器防止发动机过热。2) anti-freeze: This is a solution which is added to the cooling system to lower the temperature at which freezing of the coolant occurs: the actual freezing temperature is governed by the quantity of anti-freeze added to the system. Ice increases its volume as its temperature decreases, so extensive damage to the cylinder block will result if the coolant freezes. Most modern anti-freeze solutions contain special chemical additives called inhibitors to reduce corrosion of the metal parts. Care must be taken to avoid splashing anti-freeze on the vehicle paintwork, since some of the chemicals can soften the paint. 防冻剂溶液添加到冷却系统中,可降低冷却液冷冻的温度。冷却液实际的冷冻温度是由添加的防冻剂的数量来控制的。温度降低时,冰的体积会增加,所以冷却液一旦冷冻会给发动机缸体带来极大的损害。现在多数的防冻剂都含有特殊的化学添加剂(称为抑制剂)用于减小对金属部件的腐蚀。由于有些化学剂软化油漆,因此一定要避免把防冻剂溅到汽车的漆面上。 3) The purpose of the lubrication system is to circulate oil through the engine. An engine must have a good lubrication system. Without it, the friction heat from the contact of the moving parts would wear the parts and cause power loss.Oil, when placed between two moving parts, separates them with a film. This oil film prevents the parts from rubbing against each other. This oil film also cushions the parts, giving quieter and smoother engine operation. 润滑系统的作用是使机油在发动机里循环流动。发动机必须要有良好的润滑系统,不然移动部件相互接触摩擦而产生的热量磨损发动机部件,并损失发动机功率。机油位于两个移动部件之间,通过油膜隔开两部件。油膜防止部件之间的相互摩擦。它垫在部件之间,使得发动机工作安静、平稳可靠。4) In most cars, the oil pump is in the crankcase above the sump. It draws oil through a tube that extends downward into the sump. This tube has a filter screen over its bottom end..The screen keeps large pieces of sludge and dirt from being drawn into the pump. The tube may be hinged on the pump end so that it can move up and down as the oil level changes in the sump. Thus, the pump always draws oil from the top of the sump, not from the bottom where the dirt and sludge tend to settle. Modern cars use one of two common types of oil pumps --- the gear-type and the rotor-type. 在多数汽车上,机油泵位于油底壳上方的曲轴箱里。机油泵通过一根向下延伸到油底壳里的油管油,该油管底端有滤网,可防止大块的沉淀物和污垢吸入机油泵。油管铰接在机油泵的末端,这样在油底壳里的油面变化时油管可上下移动。机油泵总是从油底壳的上部油,而不是从污垢和沉淀物所在的底部油。目前的汽车一般有齿轮式和转子式两类机油泵可供使用。5) Three Types of harmful emission (HC, CO, NOX): There are many causes for emissions. Some emissions are caused by poor air quality. Other emissions are caused by engine fuels, such as diesel fuel or gasoline. These are hydrocarbon fuels, made up primarily of hydrogen and carbon. Emissions are colorless and odorless. Sunlight, though, will transform them into smog. 产生排放的原因有很多,一部分排放物是由于空气质量差引起的,另一部分是由柴油或汽油等发动机燃料产生的。这些碳氢化合物燃料主要由碳和氢两种元素组成。这些排放物是无色无味的,在阳光的作用下转变为烟雾。 6)The catalytic converter (or more correctly the catalytic exhaust converter) consists of metal housing, a substrate and the actual active catalytic layer. The active catalytic substances are platinum and rhodium. Platinum accelerates the oxidation of the hydrocarbons and the carbon monoxide, and rhodium accelerates the reduction of the oxides of nitrogen. 催化转化器(或更恰地称废气催化转化器)由金属外壳、基层和活性催化层组成。活性催化剂是铂和铑两种物质。铂加速碳氢化合物和一氧化碳的氧化,铑加速氮氧化合物的还原。 2.10Emission control 7) Exhaust-gas Recirculation (EGR): Exhaust-gas recirculation is a method of reducing emissions of oxides of nitrogen that has been known and applied for years. In its essential components, engine exhaust is an inert gas, i.e. a non-combustible gas. 废气再循环可降低氮氧化合物的排放,这种技术早已为人所知并应用多年。发动机废气的基本成分是一种惰性气体,也就是一种不易燃烧的气体。9)Evaporative Emission Control (蒸发排放控制): For vehicles used in the U.S and Japan, vapors in the fuel tank may not be vented freely to the atmosphere but must be led into intake manifold. A canister filled with active charcoal absorbs the vapors when the engine is stationary, and releases them to the engine when it is running. Emissions could be increased thereby, so the vapors are fed to the engine only under certain operation conditions. Venting from the canister or directly from the tank to the engine is controlled by an electronic-controlled solenoid valve. 对在美国和日本使用的汽车来说,油箱里的燃油蒸汽不能直接排入到大气中,必须引入到进气歧管中。滤气罐中充满活性,发动机静止时滤气罐收燃油蒸气,发动机工作时滤气罐释放燃油蒸气。发动机的排放会因此增加,所以只在特定的工况下才给发动机供应燃油蒸气。电磁阀控制着从滤器罐或直接从油箱到发动机的燃油蒸汽排放。 3.2 Clutch 1) Dry Friction Clutch When a vehicle is to be moved from rest the clutch must engage a stationary gearbox shaft with the engine; this must be rotating at a high speed to provide sufficient power or else the load will be too great and the engine will stall (come to rest). (p72)当汽车原地起步时,离合器要将静止的变速器轴同发动机接合起来,此时发动机必须高速旋转以提供足够大的功率,否则载荷过大将引起发动机熄火。2)The driving member (主动部分)The driving member consists of two parts: the flywheel and the pressure plate. The flywheel is bolted directly to the engine crankshaft and rotates when the crankshaft turns. The pressure plate is bolted to the flywheel. The result is that both flywheel and pressure plate rotate together. (p74) 主动部分由飞轮和压盘两部件组成。飞轮用螺栓直接连接到发动机曲轴上,随曲轴旋转而旋转。压盘与飞轮连接,这样飞轮和压盘一起旋转。3) The driven member (从动部分)The driven member, or clutch disc, is located between the flywheel and pressure plate. The disc has a splined hub that locks to the splined input shaft on the gearbox. Any rotation of the clutch disc turns the input shaft. 从动部分(或从动盘)位于飞轮和压盘之间。从动盘上有花键毂,连接着变速器上花键的输入轴。从动盘的旋转动变速器输入轴随之转动。 4) The inner part of the clutch disc, called the hub flange, has a number of small coil springs. These springs are called torsional springs. They let the middle part of the clutch disc turn slightly on the hub. Thus, the springs absorb the torsional vibrations of the crankshaft.When the springs have compressed completely, the clutch moves back until the springs relax. In other words, the clutch absorbs these engine vibrations, preventing the vibrations from going through the drive train. (P.74) 从动盘的内部(毂缘)有一些叫作扭转弹簧的小螺旋弹簧,这些弹簧使得从动盘中部相对从动盘毂能有轻微转动,从而吸收曲轴的扭转振动。压紧弹簧完全压缩时,离合器向后移动直到弹簧开始松弛。也就是说,离合器吸收发动机的振动,防止振动传递给传动系。5) Operating members (操纵机构)These are the parts that release pressure from the clutch disc. The operating members consist of the clutch pedal, clutch return spring, clutch linkage, clutch fork, and throwout bearing. The clutch linkage includes the clutch pedal and a mechanical or hydraulic system to move the other operating members. 操纵机构释放离合器盘的压力。操纵机构由离合器踏板、回位弹簧、离合器杆系、分离叉和分离轴承等组成。离合器杆系包括离合器踏板以及用来移动其它操纵部件的机械或液压操纵系统。6)Operating members (p74) When the clutch pedal is depressed, the clutch linkage operates the clutch fork. The clutch fork, or release fork, moves the throwout bearing against the pressure plate release levers. These levers then compress springs that normally hold the clutch disc tightly against the flywheel. 踩下离合器踏板,离合器杆系操纵分离叉。分离叉动分离轴承压向压盘上的分离杠杆,分离杠杆压缩压紧弹簧。通常情况下,压紧弹簧使从动盘和飞轮紧密接合。 7)Operating members : When the clutch pedal is released, the pressure plate forces the clutch disc against the flywheel. The clutch return spring helps raise the pedal. 释放离合器踏板,压盘使从动盘压紧飞轮,回位弹簧使离合器踏板抬起。8) The hydrodynamic coupling(液力偶合器) Most automatic transmissions use a hydrodynamic coupling to join the engine crankshaft to the transmission input shaft. Hydrodynamic couplings and hydrodynamic torque converters transfer the torque through fluid-flow forces. They provide advantages when driving away thanks to infinitely variable conversion of speed and torque, with the maximum torque being available at the drive-away point (engine turning, vehicle stationary). 大多数的自动变速器(AT)使用液力偶合器来连接发动机曲轴和变速器的输入轴.液力偶合器和液力变矩器通过流体流动力传递扭矩.它们的优点是起步时由于速度和扭矩的连续 变化,可在起步时(发动机运行,车辆静止)得到最大扭矩. Universal Joints (UJ) 万向节1) The suspension connects the final drive assembly to the car body. The final drive moves up and down in relation to the engine and transmission. A coupling is needed that permits movement between the final drive and transmission. The universal joints provide this coupling.(p94)悬架连接着主减速器(后桥)总成和车身。主减速器相对于发动机和变速器上下运动,这样在主减速器和变速器之间就需要万向节这种连接装置来允许其相对运动。2) Here two U-shaped pieces are placed perpendicular to one another and joined with a simple cross. The U-shaped pieces are called yokes. The cross that connects them is called a spider. The arms that extend from the spider are called trunnions. The two yokes are at a 90o angle to one another. Most cars have two universal joints, one at each end of the propeller shaft. (p94)两个U形件垂直布置,通过一个简单的十字叉连接在一起。U 形件称为万向节叉,连接万向节叉的十字叉叫作十字轴,从十字轴延伸出的臂叫作耳轴。两个万向节叉成90o布置。多数汽车采用两个万向节,在传动轴的每一端各有一个万向节。 3) A shaft which receives the drive from a cross type joint varies its speed during rotation; the greater the drive angle the greater the speed variation. A constant rotational speed can be restored by fitting a second joint in a way such that when the first joint increases its speed the second joint decreases its speed. (p95)传动轴接收十字轴式万向节传来的动力,转动时其速度发生变化。传动角越大,速度变化越大。要实等速,必须以某种方式安装第二个万向节,这样第一个万向节使转速增大,第二个万向节就使转速减少。4) The hypoid gear is in common use today due mainly to the fact that the offset pinion allows the propeller shaft to be set below, (for cars) or above, (for commercial vehicles) the crown wheel center. This gives either a reduction in the propeller shaft tunnel, which causes a bump in the vehicle floor, or in the case of a commercial vehicle a reduction in the angle through which the universal joint has to operate. (p96)在的主减速器普遍使用准双曲面圆锥齿轮,这主要是因为主动锥齿轮的偏移允许轿车上传动轴布置得比从动锥齿轮低一些,而商用车上又允许布置得比从动锥齿轮高一些。这就使得传动轴通道(凸包)(它会导致汽车车身地板形成凸起) 位置降低,或者使得商用车上万向节工作角度减小。5) Large crown wheels reduce the ground clearance under the differential. In the case of pinion axles and planetary-hub reduction axles, the differential and the half-shafts can be made smaller by splitting the reduction. This makes it possible, even in the case of high power outputs, to achieve sufficient ground clearance of the vehicle. (p96)从动锥齿轮(冠轮)尺寸大,会降低汽车的离地间隙。如果采用圆柱齿轮式和行星齿轮式轮边减速器,通过两级减速的形式可减小差速器和半轴的尺寸。这样,汽车就可以获得足够大的离地间隙,即使输出功率要求较大也可以。6) Planetary gears are used mainly in final drives, rear- mounted splitter boxes and, above all, in automatic transmissions. The simplest form of planetary gear (the planetary-gear train) consists of sun gear, ring gear and arm with planet gears. Each of the three elements may act as drive, output or may be at rest. Therefore, great variation is possible as regards the transmission ratio, ranging as far as a reversal of the direction of rotation. The parallel meshing of several gears under load permits a compact construction. (P.97)行星齿轮系主要应用在主减速器、后置副变速器和自动变速器上。最简单的行星齿轮系统由太阳轮、齿圈和行星轮组成。三部件中任意一个都可作输、输出或保持静止。这样,依照变速比的不同可得到较大的变速范围,汽车的倒行也能实。承载齿轮的平行啮合使行星轮系结构较紧凑。7) When a vehicle is cornered the inner wheel moves through a shorter distance than the outer wheel. This means that the inner wheel must slow down and the outer wheel must speed up. During this period it is desirable that each driving wheel maintains its driving action. The differential performs these two tasks. (p98) 当汽车转弯时,内侧车轮比外侧车轮行驶的距离要短,这说明内侧车轮比外侧车轮转得要慢。在此期间,维持每个驱动车轮的行驶状态是很重要的。这两个任务由差速器来完成。8) The principle of the bevel type differential can be seen if the unit is considered as two discs and a level. When the vehicle is travelling straight, the lever will divide the driving force equally and both discs will move the same amount. When the vehicle corners, the driving force will still be divided equally but the inner disc will now move through a smaller distance; this will cause the lever to pivot about its center which will prize forward the outer disc to give it a greater movement. This action shows that the torque applied to each driving wheel is always equal --- hence the differential is sometimes called a torque equalizer. (p98-99) 汽车直行时,杠杆平均分配驱动力,两个圆盘移动相同的距离。汽车转弯时驱动力仍然会平均分配,但是内侧圆盘移动的距离要小一些,这使得杠杆绕中心转动,推动外侧圆盘使之移动更大的距离。这个过程表明扭矩总是平均分配给每个驱动轮,因此差速器有时也叫做扭矩平衡装置。