重庆大学车辆工程专业英语.doc

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。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. Vapor 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 maintai