汽车工程专业英语DOC.docx

1、汽车工程专业英语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 。 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

2、和电气设备。 1.1 Body（车身） (2) The body is designed to keep passengers safe and comfortable. The body styling provides an attractive, colorful, modern appearance for the vehicle. 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（发动机） (3)The internal combustion engine is most common: this obtains its p

3、ower 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 t

4、ransmission . 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（底盘） 1.3.3 Suspension（悬架） (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 passeng

5、ers and load. It must also keep the tires in contact with the road regardless of road surface. 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（制动） (5) Drum brakes have a drum attached to the wheel hub, and braking occurs by means of brake shoes expanding against the

6、 inside of the drum. With disc brakes, a disc attached to the wheel hub is clenched between two brake pads.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。1.4 Electrical system（电气系统） (6) The electrical system supplies electricity for the starter, ignition, lights and heater. The el

7、ectricity level is maintained by a charging circuit. 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。 Chapter 2 Internal Combustion Engine 2.1.2 Engine Terms（发动机条款） 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 g

8、as, 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; 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（发动机缸体） 1) The engine block is

9、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. 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。 2.2.2 Cyl

10、inder Sleeves（气缸套） 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

11、types of sleeves: dry and wet. 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（缸盖） 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 pist

12、on. 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。 2.2.5 Oil Pan or sump （油盘或油底盖） 4) The oil pump in the lubricating system draws oil fr

13、om 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. 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

14、(活塞总成) 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。 2) In diesel engines, the combustion chamber may be f

15、ormed totally or in part in the piston crown, depending on method of injection. 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 3）Piston Rings（活塞环） 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

16、 in the groove on the piston. The rings 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。 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. Th

17、e lower end of the connecting rod fit the crankshaft journal. This is called the big end. 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 c

18、losed - this feature is useful to remember when checking valve clearances.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 th

19、e crankshaft. 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 （气门系统） 1）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 i

20、ntake stoke overlap for a short period of time. This is called valve overlap. Valve timing and valve overlap vary on different engines. 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。 2） Each cam must revolve once during the four-stroke cycle to open a valve.

21、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. 在

22、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。 2.6 Gasoline Fuel System （汽油燃烧系统） 1) 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

23、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. 汽油容易蒸发，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

24、泵的入口处易受高温，就经常出现气阻。 2) 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. B

25、ut 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） Fuel pump: Most cars today have a mechanical fuel pump. This pumps fuel out of the tank and through the fuel lines to the carbur

26、etor 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. 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。 4）

27、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, tem

28、perature, 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。 5） The throttle mechanism contro

29、ls 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

30、. 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。 2.7 Diesel Engine（柴油机） 1) 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 alt

31、ernative 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）At exhaust-gas turbo-charging, the exhaust-gas energy which would have been lost is used to drive a turbine. This

32、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。 2.8.2 Thermostat circulation（温控器循环） 1） When the engine is cool, the thermostat remains closed so that coolant cannot circulate through the radiator. Instead, coolant is recircul