发表于 2022-08-20 18:12:12 阅读 (20) 分类:汽车专业英语
The purpose of an automobile engine is to supply the power needed to move the vehicle. The engine produces this power by burning fuel inside it. Because the engine burns fuel inside, or internally, the engine is known as an internal combustion engine (ICE).
汽车发动机的功用是提供汽车行驰所需的动力。发动机通过发动机内部燃烧燃料来产生这个动力。由于燃料燃烧在发动机内部进行，这种发动机被称作内燃机。
Most automobile engines are located at the front of the vehicle. Many engines drive the rear wheels. This requires a long drive shaft extending from the front wheels to the rear wheels. Other engines drive the front wheels. In the rear-wheel-drive arrangement, the engine sits longitudinally. Its long dimension is from front to back.
对于大多数汽车，发动机布置在汽车前部。许多发动机驱动后轮，这就要求从前轮到后轮的长驱动轴。其余发动机驱动前轮。对于后轮驱动的汽车而言，发动机由前到后纵向布置。
In the front-wheel-drive arrangement, the engine sits crosswise, transversely. With either arrangement, the power is carried to the drive wheels (rear or front) by gears and shafts.
对于前轮驱动的布置，发动机横置。无论哪种布置方式，能量都是通过齿轮和传动轴传到驱动轮（前轮或后轮）。
Some cars have the engine mounted in back of the front seat. This is called a mid-engine arrangement. Other cars have been built with the engine mounted at the rear, in back of rear seat. The Volkswagen “beettle” is an example of rear.
有些汽车的发动机位于前排座椅的后面。这种布置被称为发动机中置。还有些汽车的发动机位于后部，安置在后排座椅后面。大众汽车的甲壳虫就是发动机后置的一个例子。
Various kinds of engine are used in automotive vehicles. The two major types are:The piston engine inwhich pistons move up and down, or reciprocate, in the engine cylinder. This is the engine used in all cares today, except for some models of Mazda.
2. The Wankel rotary engine in which rotate, or spin. The Mazda Motor Corporation of Japan is the major manufacturer of this engine.
汽车上使用着不同种类的发动机。它们可以分成两大类：
1、往复活塞式发动机：发动机在气缸内作上下往复运动。除了马自达公司的几款以外，现今几乎全部轿车都采用这种发动机。
2、转子发动机：活塞在气缸内作旋转运动。日本的马自达公司是这类发动机的主要生产商。
There are two types of piston engines-spark ignition (SI) and compression ignition (CI). Spark-ignition engines use an electric system with spark plugs. Electric sparks at the spark plugs ignite, or set fire, the fuel in the engine cylinders. The combustion of the fuel makes the engine run and produce power. This is the engine used in most produce power. This is the type of engine used in most automotive vehicles.
活塞式发动机可以分为两类：点燃式和压燃式。点燃式发动机使用带火花塞的点火系统。火花塞的电火花点燃发动机气缸内的燃料。燃料燃烧驱动发动机，并做功。这是大多数动力源采用的发动机，也是大多数汽车采用的发动机形式。
The compression-ignition engine uses the heat of compression to ignite the fuel.When air is compressed, it gets very hot. In the diesel engine, the air is compressed so much that its temperature goes up to 538 degrees Celsius or higher. The diesel fuel is sprayed into this very hot air and is ignited by the heat. Some automobiles have diesel engines. Many heavy-duty trucks and buses are powered by diesel engines.
压燃式发动机使用压缩产生的热量来点燃燃料。当空气被压缩，它可以达到非常高的温度。对于柴油式发动机，压缩空气可以使得空气温度达到538度或者更高。此时，柴油被喷射到这炽热的空气中，被空气的热量点燃。一些轿车使用柴油发动机。重型卡车和客车普遍使用柴油发动机。
There are other engines still in the experimental stage that might someday become important. These include gas-turbine engines, steam engines, Stirling engines, and electric motors.
还有一些目前尚且处于试验阶段，但未来可能会非常重要的发动机，比如：燃气涡轮机、蒸汽机、斯特灵发动机和电动机。
A spark-ignition engine requires four basic systems to run. Diesel engines requires three of these systems. They are fuel system, ignition system (expect diesel), lubricating system and cooling system. Each performs a basic job in making the engine run. These are described briefly below.
点燃式发动机运转需要4个基本系统，而柴油发动机需要3个基本系统。它们是燃油系统、点火系统（柴油发动机不需要），润滑系统和冷却系统。每个系统实现一个基本功能来使得发动机运转。下文将简短介绍这些系统。
The fuel system supplies gasoline or diesel fuel to the engine. This fuel is mixed with air to make a combustible mixture (a mixture that will run). Each cylinder is repeatedly filled with the mixture. Then, the mixture is ignited or burned, producing high pressure. The high pressure makes the piston move (or rotors spin). This turns shafts that rotate the wheels, causing the vehicle to move.
燃油系统给发动机提供汽油或柴油燃料。燃油与空气混合形成可燃混合气。发动机的每个气缸重复充满这种可燃混合气，然后它们被点燃或压燃，产生高压。这个高压使得发动机活塞运动（或者转子旋转），驱动轴来旋转车轮，从而使得汽车行驶。
Every time the fuel system delivers air/fuel mixture to a cylinder, the ignition system follows up by a delivering an electric spark. This ignite the mixture which creates the high pressure that moves the pistons and turns the car wheels. The action is repeated many times each second while the engine is running.
每当燃油系统将可燃混合气送至气缸，点火系统接着就发出电火花来点燃缸内的可燃混合气，从而产生高压，使得活塞运动和汽车行驶。当发动机运转时，每秒钟要点火多次。
The ignite system takes the low voltage of the battery and builds it up to a very high voltage: as high as 47,000 volts in some systems. This high voltage jumps the gaps in the spark plugs, producing the sparks that ignite the air/fuel mixture in the engine cylinders.
点火系统将电池的低电压升压到高压。对于某些系统，可以达到47000伏。这个高压击穿火花塞间隙，产生电火花，点燃发动机气缸内的可燃混合气。
The engine has many moving metal parts. If metal parts rub against each other, they will wear rapidly.To prevent this, engines have lubricating oil. The oil gets between the metal parts so they slide on the oil, and not on each other.
发动机有许多运动金属部件。如果这些金属部件相互摩擦，那它们磨损就会很快。为了防止这种情况，发动机使用润滑油。润滑油在金属部件之间，使得金属部件在油膜上滑动，而不是彼此之间的摩擦。
The lubricating system has an oil pan at the bottom of the engine which holds several quarts (liters) of oil. An oil pump, driven by the engine, sends oil from this reservoir through the engine. After circulating through the engine, the oil drops back to the oil pan. The oil pump continues to circulate the oil as long as the engine is running.
发动机润滑系统在发动机底部有一个储存几升汽油的油底壳。由发动机驱动的油泵将油从油底壳泵到发动机循环流动。在发动机循环后，润滑油流回到油底壳。只要发动机在运转，油泵就始终使润滑油循环流动。
Where there is fire (combustion), there is heat. Burning of the air/fuel mixture raises the temperature inside the engine cylinders several thousand degrees. Some of this heat produces the high pressure that moves the pistons to produce power. Some of the heat leaves the cylinders with the exhaust gas. The exhaust gas is what is left after the air/fuel mixture burns. It is cleared out of the cylinders after the combustion is complete.
哪里有燃烧，哪里就有热量。可燃混合气的燃烧使得发动机气缸内温度上升数千度。部分热量产生高压来驱动活塞产生动力。部分热量伴随排放气体被带出气缸。排放气体指的是可燃混合气燃烧后剩余物。当燃烧结束，排放气体被排出气缸。
Some of the heat is removed by the circulating oil. After the hot oil drops down into the oil pan, the oil gives up some of this heat to the air passing under the oil pan. The rest of the heat is removed by the cooling system.
部分热量被循环油带走。当温度较高的油流回到油底壳，热量通过油底壳下流动的空气带走。剩余的热量就要使用冷却系统来带走。
An engine will run with the four basic systems described above-fuel, ignition, lubricating and cooling. However, three other related systems are also necessary. These are the exhaust system, the emission-control system, and the starting system.
具备上述的燃油、点火、润滑和冷却系统，发动机就可以运转。但是，其余相关的3个系统也是非常必需的。它们是排放系统、排放控制系统和启动系统。
The exhaust system reduces the noise of the burned gases leaving the engine cylinders and carries these exhaust gases safely away from the people in the car. The emission-control system is required by law to reduce the air pollution the engine could produce. The starting system is needed to crank the engine. A battery provides the electric power to operate the starting motor and the ignition system during cranking.
排放系统减少发动机气缸可燃混合气燃烧时的噪音，并且将废气安全带走，使其远离车厢内的人。排放控制系统是法律强制要求的，用来减少发动机产生的空气污染。启动系统是用来启动发动机。启动过程中，由电池给启动电机和点火系统提供能量。
The internal combustion engine is a device used to convert the chemical energy to the fuel (gasoline or diesel fuel) into heat energy, and then to convert this heat energy into usable mechanical energy. This is achieved by combining the appropriate amounts of air and fuel, and burning the mixture in an enclosed cylinder at a controlled rate. A movable piston in the cylinder is forced down by the expanding gases of combustion.
发动机是一个将燃料（汽油或柴油）的化学能转化成热能，再将热能转化成可利用的机械能的装置。实现这个能量的转化是通过混合适当的空气和燃油，并在密封的气缸内以一个可控的速率燃烧这个可燃混合气来实现的。燃烧产生的膨胀气体强迫气缸内的活塞运动。
An average air/fuel ratio for good combustion is about 15 parts of air to 1 part of fuel by weight. This means that for every gallon of gasoline burned, the oxygen is about 9,000 to 10,000 gallons of air is required. Air is about 21% oxygen and 78% nitrogen.
可燃烧良好的空燃比，按质量大约是15：1。这就意味着燃烧1加仑汽油需要的9000到10000加仑的空气里的氧气。空气大约有21%的氧气和78%的氮气。
Diesel engine operate on a much wider air/fuel ratio, since air intake is not regulated on most diesels. Ratios may range from about 20:1 to 100:1. The fact, plus the high compression of the diesel, makes it a very fuel efficient engine.
由于大多数的柴油机并不控制进气，柴油机的空燃比范围很宽，从20：1到100：1。再加上柴油混合气具有很高的压缩比，这使得柴油机的效率很高。
The movable piston in the cylinder is connected to the top of a connecting rod. The bottom of the connecting rod is attached to the offset portion of a crankshaft. As the piston is forced down, this force is transferred to the crankshaft, causing the crankshaft to rotate. The reciprocating (back and forth or up and down) movement of the piston is converted to rotary (turning) motion of the crankshaft, which supplies the power to drive the vehicle.
气缸内的活塞与连杆的上部相连，而连杆的下部与曲轴的偏移部连接。因此，当活塞向下运动时，这个运动传递到曲轴，使得曲轴旋转。活塞的往复运动（前后或者上下）就转化为曲轴的旋转运动，从而给汽车行驶提供动力。
The efficiency of the internal combustion, reciprocating piston engine in converting the potential energy in fuel into mechanical energy is only about 33%. Of the available heat energy in the fuel, about one-third is lost through through the exhaust system and one-third is absorbed and dissipated by the cooling system. Of the remaining one-third, about one-half is lost through available at the vehicle’s drive wheels.
往复活塞式内燃机将燃料的能量转化为机械能的效率大约是33%。燃料中可利用的热量有三分之一通过排气系统丢失掉，另有三分之一被冷却系统吸收和带走，剩下的三分之一大约有一半的能量在汽车的驱动轮消耗掉。
The overall efficiency of the diesel engine is considerably higher than that of the gasoline engine. The reason for this are: the higher compression ratio, the higher air/fuel ratio, and the higher heat value of the fuel. The useful power developed at the drive wheels by a diesel engine is about 25% compared to 15% by a gasoline.
与汽油机相比，柴油机的总体效率要高很多。这是因为柴油机具有更高的压缩比，更高的空燃比，柴油的热量也要更高。对于柴油机，驱动轮得到的能量大约可以达到总能量的25%，而汽油机只有15%。
The movement of the piston from its uppermost position (TDC, top dead center) to its lowest position (BDC, bottom dead center) is called a stroke. Most automobile engines operate on the four stroke-cycle principle. A series of events involving four strokes of the piston completes one cycle. These events are: (1) the intake stroke, (2) the compression stroke, (3) the power stroke, and (4) the exhaust stroke. Two revolutions of the crankshaft and one revolution of the camshaft are required to complete one cycle.
活塞从它在气缸内的最高位置(上止点)运动到最低位置(下止点)称为一个冲程。大多数汽车发动机采用四冲程工作循环，由活塞的四个冲程组成一个工作循环，分别是：进气冲程、压缩冲程、作功冲程和排气冲程。发动机的一个工作循环需要曲轴旋转两次，凸轮轴旋转一次。
On the intake stroke the piston is pulled down in the cylinder by the crankshaft and connecting rod. During this time the intake valve is held open by the camshaft. Since the piston has moved down in the cylinder, creating a low-pressure area (vacuum), atmospheric pressure forces a mixture of air and fuel past the intake valve into the cylinder. Atmospheric pressure is approximately 14.7 pounds per square inch (about 101.35 kilopascals) at sea level. Pressure in the cylinder during the intake stroke is considerably less than this. The pressure difference is the force that causes the air/fuel mixture to flow into the cylinder, since the liquid or a gas (vapor) will always flow from a high-pressure to a low-pressure area.
吸气冲程过程中，气缸内的活塞被曲轴和连杆向下拉动。此时，凸轮轴使得进气门打开。由于活塞在气缸壁向下运动，产生了一个低压区（真空区），大气压力使得可燃混和气从进气门进入气缸。海平面的大气压大约是每平方英寸14.7磅（大约101.35千帕）。吸气冲程时，气缸内的压力要远远小于大气压。由于液体和气体总是从高压区流向低压区，因此，气缸内外的压力差就使得可燃混和气流入气缸。
As the piston is moved up by the crankshaft from BDC, the intake valve closes. The air/fuel mixture is trapped in the cylinder above the piston. Further piston travel compresses the air/fuel mixture to approximately one-eighth of its original volume (approximately 8:1 compression ratio) when the piston has reached TDC. This completes the compression stroke.
当曲轴推动活塞从下止点起向上运动，进气门关闭。可燃混和气被限制在活塞以上的气缸区域内。当活塞达到上止点时，活塞压缩可燃混合气至其原有容积的1/8（大约8:1的压缩比）。此时，压缩冲程结束。
When the piston is at or near TDC, the air/ fuel mixture is ignited. The burning of the air/fuel mixture (combustion) takes place at a controlled rate. Expansion of the burning mixture causes a rapid rise in pressure. The increased pressure forces the piston down on the power stroke, causing the crankshaft to rotate.
当活塞达到或接近上止点时，可燃混和气被点燃，并且在一个可控的节奏下进行。可燃混和气的膨胀使得压力急剧上升，并推动活塞向下运动作功，使得曲轴旋转。
当活塞达到或接近上止点时，可燃混和气被点燃，并且在一个可控的节奏下进行。可燃混和气的膨胀使得压力急剧上升，并推动活塞向下运动作功，使得曲轴旋转。
At the end of the power stroke, the camshaft opens the exhaust valve, and the exhaust stroke begins. Remaining pressure in the cylinder, and upward movement of piston, force the exhaust gases out of the cylinder. At the end of the exhaust stroke, the exhaust valve closes and the intake valve opens, repeating the entire cycle of events over and over again.
作功冲程结束时，凸轮轴打开排气门，排气冲程开始。气缸内剩余的压力和活塞向上的运动把废气排出气缸。排气冲程结束时，排气门关闭，进气门开启，从而再次重复整个循环。
To start the engine, some method of cranking the engine is required to turn the crankshaft and cause piston movement. This is done by the starter motor when the ignition key is in the start position. When sufficient air/fuel mixture has entered the cylinders and is ignited, the power strokes create enough energy to continue crankshaft rotation. At the point, the ignition key is released to the run position and starter is disengaged.
为了起动发动机，需要转动曲柄来使得活塞运动。当点火开关置于起动位置时，起动电机转动曲柄，起动发动机。当足量的可燃混和气进入气缸并被点燃，作功冲程产生的能量足以使得曲轴连续转动。此时，点火开关释放到正常位置，起动机推出啮合。
Sufficient energy is stored in the flywheel and other rotating parts on the power stroke to move the piston and related parts through the other three strokes (exhaust, intake, and compression). The amount of air/fuel mixture allowed to enter the cylinder determines the power and speed developed by the engine.
在作功冲程中，大量的能量被储存在飞轮和其他旋转部件上，从而在其余三个冲程中可以使得活塞和相连部件运动。进入气缸的可燃混合气的数量决定了该发动机的功率和转速。
Ⅰ What is the purpose of an automotive engine?Ⅰ
To supply the power needed to move the vehicle.
What is the difference between a gasoline engine and a diesel engine?
A gasoline engine uses an electric ignition system with spark plugs to ignite the fuel. And a diesel engine uses the heat of compression to ignite the fuel.
What are the basic systems to run a spark-ignition engine required?
Fuel system, ignition system, lubricating system and cooling system.
List the strokes of a four-stroke-cycle gasoline engine operation.
The intake stroke, the compression stroke, the power stroke and the exhaust stroke.
What is the function of the flywheel?
It is used to store sufficient energy to move the piston and related parts through the other strokes (exhaust, intake and compression).
Ⅱ 1 A car usually has a piston engine. It consists of several moving part: pistons, connecting rods, crankshaft, camshaft, valve lifters, intake valves and exhaust valves. The cast iron or aluminum engine block holds the moving parts. The engine block has a series of holes which are called cylinders. The cylinders can be arranged in line or in a V-shape and in the upper part of the block. Each cylinder holds a piston and the connecting rod. A circular ring is used to seal the small gap between the piston and the cylinder wall. The lower part of the block is called crankcase which holds the crankshaft with bearing mounts. Pistons are connected to the crankshaft by connecting rods.
汽车一般使用活塞式发动机。活塞式发动机由活塞、连杆、曲轴、凸轮轴、气门挺杆、进气门和排气门等运动部件组成。这些运动部件安置在铸铁或铝合金机体内。发动机体上有些凹洞，这些凹洞被称作气缸。气缸在机体上部呈直列式或V型排列。每个气缸都有活塞和连杆。活塞和气缸壁之间的微小缝隙通过一个圆环密封。机体的下部是曲轴箱，里面是带有轴承的曲轴。活塞和曲轴之间通过连杆连接。
2 The cylinder heads are the top covers of the cylinders which are tightly bolted to the top of the block. The cylinder heads contain combustion chambers. Each combustion chamber contains at least one intake and exhaust valve and one spark plug per cylinder. The valves are opened and closed in a specific sequence with valve lifters controlled by the camshaft. The camshaft is connected to the crankshaft through a time belt.
气缸盖是气缸的上盖，其通过螺栓与上机体连接。气缸盖下是燃烧腔。每个气缸的每个燃烧腔都至少要有一个进气门，一个排气门和一个火花塞。气门被由凸轮轴控制的气门挺杆按一定的顺序打开和关闭。凸轮轴和曲轴之间通过正时带连接。
汽车专业英语(第二版)
作者: 黄韶炯 赵建柱 编
出版社: 人民交通出版社
ISBN: 9787114102950
