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汽车专业外文翻译5

汽车专业外文翻译5
汽车专业外文翻译5

英文翻译

Motor Cars

1. How the Engine Works

An engine that converts heat energy into mechanical energy is called a heat engine ,and the car engine is one type of heat engine. It derives heat from the burning or 'combustion', of a fuel and converts this heat into useful work for driving the car.

The fuel used in the vast majority of car engines is petrol, which is one of the many products obtained from crude oil found in the earth. Petrol, when mixed with the right amount of air, will burn when a flame or spark is applied to it.

In the car engine, air mixed with petrol is taken into a confined space and compressed. The mixture is then ignited and it burns. In burning it heats the air, which expands, and the force of expansion is then converted into a rotary movement to drive the wheels of the car.

To be able to use this energy effectively we have to control the burning or combustion process and the force of expansion. Firstly, we need a tube, or 'cylinder', closed at one end, in which to compress and burn the petrol and air mixture. Then we need a piston which can slide freely in the cylinder, and which can be driven outwards by the

force of expansion. To convert the outward movement of the piston into a rotary movement we must join it by a connecting rods to a crankshaft. We need one passage for the entry of the mixture into the cylinder and another to let out the used gases. To control the entry of the mixture and the exhaust of the gases we need valves, and these are called the inlet and exhaust valves. Finally, we need some means of igniting the mixture in the top of the cylinder, the part called the combustion chamber; and for this we use a sparking plug.

By timing the opening and closing of the valves and by timing the arrival of the spark we can control the whole sequence of events and make the piston move in and out over and over again.

THE CYLINDERS

Motor-car engines may have four, six, or eight cylinders. Look at figure 1.These cylinders are usually mounted in a cylinder block on top of the engine. Beneath the cylinder block is the crankcase, which contains two shafts, the crankshaft and the camshaft. As you have read, the crankshaft is revolved by the outward movement of

the pistons in the cylinders. This rotary movement of the crankshaft transmits the power developed by the engine through the gearbox to the driving wheels and sets the car in motion.

When the crankshaft rotates it also causes the rotation of the camshaft, which lies alongside it in the crankcase. As the camshaft rotates, it pushes up rods alongside each cylinder to open and shut the valves at the top of the cylinder.

There are two valves to each cylinder. The inlet valve lets air and petrol into the combustion chamber of the cylinder when it is opened. When the exhaust valve is opened the gases formed after the combustion in the chamber are allowed to escape . These gases are led away from the car through an exhaust pipe.

Let us examine the action of one of the cylinders in more detail. Look at figure 2.In (a) the piston is near the top of the cylinder with the inlet valve open and the exhaust valve closed, If the crankshaft is turned, either by hand or by the starter motor ,the piston is drawn down by the connecting rod and a charge of petrol-air mixture rushes in. When the piston reaches the bottom of its stroke the inlet valve is closed by the action of a spring. This stroke is called the induction stroke.

In (b) both valves are closed and the crankshaft forces the piston up to compress the mixture in the top of the cylinder. This, then, is called the 'compression' stroke. Towards the end of the compression stroke a spark from the sparking plug causes the mixture to ignite.

In (c) we see that the heat of combustion has caused a rapid rise in pressure in the combustion chamber and this has forced the piston down. Through the connecting rod the piston causes the crankshaft to continue to rotate. This stroke is called the

'expansion' or 'power' stroke, and we can say now that the engine has 'fired'. At the end of

this stroke, as the crankshaft rotates, causing the camshaft alongside it to continue to rotate, one of the cams on the camshaft pushes up the rod, which causes the exhaust valve to open, allowing the exhaust gases to escape.

In (d) we see the fourth and final stroke, the 'exhaust' stroke. The exhaust valve has been forced open by the rotation of the camshaft, and the crankshaft, continuing to rotate, drives the piston back up the cylinder, forcing out the exhaust gases. At the end of this stroke the exhaust valve is closed by the action of a spring, and the camshaft, continuing to rotate, pushes up a second rod to force the inlet valve open. Now the cylinder will receive another charge of petrol-air mixture, and the sequence of four strokes, 'induction', 'compression', 'expansion' or 'power', and 'exhaust', will start

again.

Because there is a four-stroke sequence, or 'cycle', in this type of internal combustion engine it is called a four-stroke engine. There are also two一stroke engines used, for example, for motor scooters, and for some motor cycles.

Let us think of a car with four cylinders. Remember that it is only on the expansion stroke that power is transmitted to make the crankshaft rotate. Let us number the cylinders, 1,2,3,4. They may transmit power in this order. 1,2,4,3. This means that when number 1 cylinder is on the expansion stroke, number 2 is on the compression stroke, number 4 is on the induction stroke, and number 3 cylinder is on the exhaust stroke. The four pistons, moving up and down inside their cylinders in this order, push down rods connected to the crankshaft at different times and at different points along its shaft. This keeps the crankshaft revolving and the crankshaft, when the gears are engaged, keeps the car moving.

2. The Fuel and Ignition Systems

The fuel system includes a fuel tank, a fuel pump, and a carburetor.

The fuel pump may be operated either mechanically from the engine camshaft or electrically. Its function is to pump petrol from the petrol tank and deliver it to the carburetor. It contains a fine filler to exclude particles of dust or dirt which may have found their way into the tank.

The carburetor is mounted on the inlet pipe, or inlet 'manifold', which leads to the inlet valves of each cylinder. Its function is to 'carburet', or mix, the required amounts of petrol and air for combustion in the cylinders. It regulates automatically the proportions of petrol and air and also allows the driver to control the rate of delivery of the mixture, and so vary the speed of the engine.

See figure 3. This is a simple type of carburetor. It makes use of a fuel reservoir or "float chamber" to which petrol is pumped by the petrol pump. The level of the petrol in. the chamber is kept constant by the action of a float which, as it rises with the petrol, closes a needle valve when the correct level is reached. The petrol from the float chamber flows to a small jet situated in a narrow tube called the choke tube. When the engine is running, i.e. when the pistons are moving up and down in the cylinders, air is drawn in and passes through the choke tube. Here it mixes with the petrol and passes out into the inlet manifold of the engine. The amount of mixture allowed to pass is controlled by a butterfly valve, or ’throttle', situated in the carburetor outlet. This valve is operated by the accelerator pedal. An air cleaner may be connected to the air inlet to remove dust from the air and prevent it getting into the

cylinders and down into the engine lubricating oil, where it can cause increased engine wear.

The proportion of air and petrol required at varying engine speeds is controlled automatically. When starting a cold engine a much richer mixture, one with a higher proportion of petrol to air, is required. This is obtained by restricting the amount of air entering the carburetor. In most cars the driver does this by pulling out a knob called the choke and this partly closes the tube carrying air to the cylinders. The driver must remember to push the choke in again as soon as possible after starting to avoid damage to the engine and waste of fuel.

THE IGNITION SYSTEM

The function of the ignition system is to provide the spark in the combustion chamber to ignite the mixture of petrol and air at the right instant. The system nor many comprises a coil, a distributor, and sparking plugs.

The coil produces the high-voltage impulse required to make the spark at the sparking plugs. It really consists of two coils of insulated wire wound one around the other so that the number of turns in the inner, 'secondary', coil is much greater than that in the outer, 'primary', coil.

A low voltage is supplied to the primary coil and suddenly interrupted. At that moment an impulse at very much higher voltage is induced in the secondary coil.

V oltages of 6 or 12 volts supplied to the primary, low一tension, coil result in voltages of 10,000 volts or more being obtained from the secondary, high tension, coil. When the car is started the low-tension supply is provided by the car's battery.

Remember that the low-tension supply must be broken suddenly to produce the high-tension supply from the secondary coil. This is done in an instrument called the distributor. The distributor is placed between the coil and the sparking plugs.

Inside the distributor are contact points. The contact between them is broken by a revolving cam, which forces them apart. Then they are forced together again by a spring pressing against the arm holding one contact. It is when the contact points are forced apart that the low一tension supply, going through a lead to the coil, is suddenly interrupted.

A second lead, going from the coil back to the distributor, conveys the high-tension (H.T.) supply to the distributor head. From there other leads distribute the H. T. supply to each of the sparking plugs in turn.

You will remember that each cylinder of the car has a sparking plug. The metal part of the sparking plug is screwed into the combustion chamber of the cylinder. The

plug contains two electrodes with a small gap between them. When the plug receives a high-tension impulse from the distributor a spark is caused as the impulse jumps the gap between the two electrodes. This spark ignites the petrol-air mixture in the combustion chamber.

3. Cooling and Lubricating the Engine

The combustion of the mixture in the engine naturally makes a great deal of heat and the engine must not be allowed to become overheated. The function of the cooling system is to control this heat.

The engine may be either water or air cooled, but the vast majority is water cooled. Water in the water jacket surrounding the cylinders picks up the surplus heat from the engine and the heated water rises. It then circulates through the radiator, where it is cooled by the passage of air past the radiator tubes, and returns to the bottom of the water jacket. A fan, which is driven from the engine crankshaft, assists cooling by increasing the draught through the radiator at low speeds. A pump may be used to help in circulating the water.

The engine must also be prevented from running too cool and therefore the temperature of the water is normally controlled within certain limits by the action of a device known as a thermostat. This has the effect of varying the circulation of the water so that, for instance, when the engine is first started less water is allowed to circulate and the engine warms up quickly.

The cooling system can, of course, freeze up in very cold weather, and this can cause considerable damage. For this reason it is advisable to add good antifreeze solution, on that can be left in throughout the summer, which will prevent freezing in winter and protect the system from corrosion all the year round.

THE LUBRICATION SYSTEM

Lubrication is necessary for two main reasons to reduce friction and wear in the engine, and to help carry away was to heat from the bearings, in which the crankshaft and camshaft revolve inside the crankcase, from the pistons, and from the other working parts. In addition, it helps the piston rings to seal in the combustion gases, to prevent them escaping down into the cylinders. (These piston rings are rings fitted into grooves around the top of each piston.)

The majority of engines have what is known as a 'force feed', or pressure, lubricating system. The bottom of the crankcase is enclosed by a sheet-metal pan, or 'sump'. This holds the engine lubricating oil and has a drain plug through which used oil may be drained off. A pump draws oil from the sump and pumps it through a filter

and then through channels, called 'oil ways', to the bearings of the crankshaft and camshaft, and also to the valve gear. At the same time, oil flowing from the bearings forms an oil mist in the crankcase and this mist lubricates the cylinder walls.

A warning light or oil gauge, controlled by the pressure of the oil in the system, is usually provided so that the driver will know when the system is not functioning and the oil is not circulating properly. If the system is not functioning properly the working parts may seize up and cause serious damage to the car engine. It is, therefore, essential for the driver to stop the engine as soon as he sees his warning light come on.

4. The Brakes

The brakes function by absorbing in friction the energy possessed by the moving car. In so doing they convert the energy into heat.

There are two types of brakes, the drum brake and the disc brake. Either or both types may be fitted, but where both types are used it is usual for the disc brakes to be fitted to the front wheels.

DRUM BRAKES

The drum brake consists of a pair of semicircular brake shoes mounted on a fixed back plate and situated inside a drum. This drum is fixed to the road wheel and rotates with it. One end of each shoe is on a pivot and a spring holds the other end in contact with the piston of a hydraulic cylinder. (In front brakes it is usual to use two hydraulic cylinders in order to equalize the pressures exerted by the shoes. See figure 4.) Each shoe is faced with material, known as brake lining, which produces high, frictional resistance.

The hydraulic system comprises a master cylinder and the slave cylinders, which are the cylinders on the road wheels. The slave cylinders are connected to the master cylinder by tubing and the whole system is filled with hydraulic fluid. A piston in the master cylinder is connected to the brake pedal, so that when the driver depresses. The pedal the fluid is forced out to each slave cylinder and operates their pistons. The fluid pushes the pistons out of their cylinders. They, in turn, push against the inner ends of the brake shoes and force them against the brake drums in each wheel. We say that the brakes are on. This friction of the shoes against the drums, which are fixed to the road wheels, slows down or stops the car. As the brake pedal is allowed to come up, the hydraulic fluid returns to its original position, the pistons retract, and a spring attached to each brake shoe returns it also to its original position, free of the brake drum. Now we say that the brakes are off.

The brakes may also be operated by mechanical linkages from the foot pedal and handbrake lever. Common practice is to operate both from and rear brakes hydraulically with a secondary mechanical system operating the rear brakes only from the hand lever. One of the great advantages of hydraulic operation is that the system is self-balancing, which means that the same pressure is automatically produced at all four brakes, whereas mechanical linkages have to be very carefully adjusted for balance. Of course, if more pressure is put on one of the brakes than on the others there-is a danger that the car will skid.

The mechanical linkage operating on the rear brakes is a system of rods or cables connecting the handbrake lever to the brake-shoe mechanisms, which work entirely Independently of the hydraulic system.

Drum brakes are prone to a reduction in the braking effort, known as 'fade', caused by the overheating of the linings and the drum. Fade can affect all or only some of the brakes at a time, but it is not permanent, and full efficiency returns as soon as the brakes have cooled down. However, fading is unlikely to occur except after the brakes have been used repeatedly in slowing the car from a high speed or after braking continuously down a steep hill. Descending such a hill, it would have been preferable to use engine braking by changing down into a lower gear. Drum brakes can be made less prone to fade by improving the cooling arrangements, by arranging for more air to be deflected over them, for example.

DISC BRAKES

The disc brake consists of a steel disc with friction pads operated by slave hydraulic cylinders. The steel disc is attached to the road wheel and rotates with it. Part of this steel disc is enclosed in a caliper. (See figure 5) This caliper contains two friction pads, one on each side of the disc, and two hydraulic cylinders, one outside each pad. The pads are normally held apart by a spring, but when the driver depresses the brake pedal, pistons from the hydraulic cylinders force the pads against the sides of the disc. Because the disc is not enclosed all the way round, the heat generated when the brakes are applied is dissipated very much more quickly than it is from brake shoes which are entirely enclosed inside a drum. This means that disc brakes are less prone to fade than drum brakes.

汽车

1. 发动机如何工作

一个把热能源转换成机械的能源的发动机叫做一个热发动机,而且汽车发动机是热发动机的一个类型。它源自烧或’燃烧’的热, 燃料和进入驾驶汽车的有用的工作之内依靠这热能。

被用于相当多汽车发动机的燃料是汽油,是从在地球被发现的原油提取得的许多产品之一。汽油,当和正确量空气混合,当火焰或者火花适用于它时,将会燃烧。

在汽车发动机中,和汽油混合的空气进入被限制的空间之内而且被压缩。当时的混合被点燃,而且它燃烧。在燃烧它方面加热扩张的空气,扩充的力量然后转换成一次旋转的运动驾驶汽车的轮子的动力。

能够有效地使用这一能源我们必须控制燃烧程序和它扩充的力量。第一,我们需要一个管或’圆筒’, 关闭在一端,在一个压缩并且燃烧汽油和空气混合的空间。然后我们需要一个能在圆筒中自由地滑动的活塞,和一个能向外地驱使装置。

力量的扩充。把活塞的循环运动转换成我们固定的连接竿杆,组成一个活塞总成参加它的一次旋转的运动。我们进入圆筒之内为混合的进入需要一个通道和另外的放出二手的废气。控制混合的气体进入和废气的排气我们需要活门,和这些叫做进气门和排气门。最后,我们需要在缸的顶端中点燃混合的一些方法,部份认为燃烧室;而且为这我们使用一个火花塞。

安排气门的正时和点火的正时达到我们能控制事件的整个序列而且作活塞动作在和在车轮运转。

气缸

汽车发动机可能有四,六,或八个气缸。审查图 1 。这些气缸在发动机的一个在顶端气缸区段中通常被装。在气缸区段是包含两个桥、活塞总成和凸轮轴的曲桥箱之下。因为你读,活塞总成因气缸中的活塞的向外运动而考虑。活塞总成的这次旋转运动传输对驱动轮经过齿轮箱被发动机发展的力量而且启动汽车。

当活塞总成替换它也引起在曲桥箱中依傍它躺卧的凸轮轴的旋转。如凸轮轴替换,它依傍在气缸的顶端打开而且关上活瓣的每个气缸强行上升竿。

对每个气缸有两个气门。当它被打开时,插入物气门让空气和汽油进去气缸的燃烧室。当在室的燃烧被允许流漏之后,排气气门被打开被形成的瓦斯。这些瓦斯经过一个排气管被引导远离汽车。

让我们更详细地调查气缸之一的行动。审查图 2 。以插入物在活塞中(一)在气缸的顶端附近气门公开和排气气门关闭,如果活塞总成是用手或藉着起动器马达,转活塞被连接竿所画向下和一项汽油-空气混合匆促的费用在。当活塞到达插入物气门因春天的行动而关闭的它的笔划的底部。这笔划叫做归纳法笔划。

在(b)两者的气门被关闭和活塞总成向上强迫活塞在气缸的顶端中压缩混合。这,当时,叫做’压缩’笔划。向压缩的结束划尾桨闪烁塞子的火花导致混合点燃。

在我们里面(c)见到燃烧的热已经在燃烧室中引起在压力方面的迅速提高,而且这已经把活塞强迫下来。经过连接竿,活塞导致活塞总成继续替换。这笔划叫做’扩充’或者 " 笔划有力量 " ,而且我们现在能说发动机已经 " 点燃 " 。在

这笔划,当做活塞总成替换,靠引起凸轮轴它继续替换,凸轮之一在凸轮轴上强行上升导致排气气门打开的竿,让废气流漏。

在我们里面(d)见到第四个和最后一笔划," 用尽 " 笔划。排气气门已经被强迫开着的藉着凸轮轴的旋转,和活塞总成,继续替换,在气缸上面驾驶活塞背面,挤出废气。在这笔划结束的时候,排气气门因春天的行动,和凸轮轴而关闭,继续替换,强行上升第二支竿强迫插入物气门公开。现在气缸将会受到汽油-空气混合的另一项费用和四笔划, '归纳法’, '压缩’的序列, '扩充’或者", 有力量 " 而且 " 用尽 ", 将会再次开始。

因为有四笔划的序列,或 " 循环 ", 在这类型的内在燃烧发动机中,它叫做一个四笔划的发动机。也有两一笔划用的发动机,举例来说,为马达的摩托车,而且为一些马达循环。

让我们用四个气缸想到一辆汽车。记得它只有在力量被传送到的扩充笔划上让活塞总成辐状。让我们数气缸, 1,2,3,4. 他们可能以这顺序传输力量。1,2,4,3. 这意谓,当号 1个气缸在扩充笔划上时, 2 号在压缩笔划上, 4 号在归纳法笔划上,而且号 3个气缸在排气笔划上。这四个活塞,在他们的气缸内上下地移动以这顺序,推向下竿在不同时间对活塞总成连接和在不同的点沿着它的桥。这使活塞总成保持回转和活塞总成,当齿轮是忙碌的,使汽车保持感人。

2. 燃料和点火系统

燃料系统包括一个燃料箱,一个燃料泵,和一个喷油装置。

燃料泵可能被操作或机械地从发动机凸轮轴或电地。它的功能是抽来自汽油箱的汽油而且递送它给喷油装置。它包含一个好填充物排除灰尘或者可能发现他们的方法进入战车的污垢的粒子。

喷油装置在插入物管、或插入物导致每个气缸的插入物气门的 " 复写 " 上被装。它的功能将与碳化合 ", 或为气缸的燃烧混合、必需汽油和空气。它自动地管理汽油和空气的比例以及让驾驶员控制混合的递送的比率,而且因此改变发动机的速度。

见图 3 。这是一个简单类型的喷油装置。它利用一个燃料水库或者 " 漂流物室 " 到哪一个汽油被汽油泵抽。汽油的水平在。室是漂流物的行动的被保

持的常数,因为它以汽油上升,当正确的水平被达成时,关一个针气门。从漂流物室流程到位于狭窄的管的小喷气式飞机的汽油呼叫抗流圈管。当发动机正在跑,也就是当活塞正在上下地在气缸中移动,空气被画在和经过抗流圈管的途径。在这里它进入发动机的插入物复印本之内在外和汽油和途径混合在一起。大的混合允许对途径被一个蝴蝶气门控制,或 " 扼喉咙 ", 位于在喷油装置出口中。这一个气门被加速者踏板操作。一个空气清洁工人可能被连接到空气插入物进入发动机润滑油,它能引起发动机穿着增加之内从空气移开灰尘而且阻止它进入气缸而且坠落。

空气和汽油的比例必需的以不同发动机速度自动地被控制。当开始一个寒冷发动机一个非常富有的混合,一与晾干制的汽油较高的比例,被需要。这藉由限制进入喷油装置的大量的空气被获得。在大多数汽车中,驾驶员藉由拉出一个拉手利做这呼叫抗流圈和这部分关将空气携带到气缸的管。驾驶员一定记得去推动抗流圈在再次尽快地在开始之后避免对燃料的发动机和废弃物的伤害。

点火系统

点火系统的功能将提供在燃烧室中的火花在正确的立即点燃汽油和空气的

混合。系统也不多数包含卷,一个经销商,而且闪烁塞子。

卷生产高电压冲动必需的在闪烁塞子作火花。它真的有绝缘的电线两卷创伤一在另一个以便内部者的旋转的数字, " 中级的 " 的周围,卷在外部、 " 主要的 " 者,卷中比那棒许多。

低的电压被提供给主要的卷而且突然打断。在非常非常高的电压的片刻一种冲动正在在中级的卷中感应。6 或 12 伏特的电压提供给主要、低的一紧张,卷造成从中级、高度紧张,卷被获得的 10,000 伏特 10,000 伏特更多的电压。当汽车被开始低压的补给是由汽车电池提供。

记得低压的补给一定突然被打破生产中级的卷的高压的补给。这在一个器具被做打电话给经销商。经销商在卷和闪烁塞子之间被放置。

在经销商内是连络点。他们之間的连络被一个分别地强迫他们的回转的凸轮打破。然后他们被一起再次强迫春天压迫对抗手臂把持一连络。它是何时连络点被分别地强迫低一紧张补给,对卷经过一个领引,突然被打断。

第二个领引,从卷去回到经销商,向经销商头提供高压的(H.T.)补给。从在那里其他领引分配 H 。T。这闪烁提供给每个依次插入。

你将会记得汽车的每个气缸有一个闪烁塞子。闪烁塞子的金属制部份进入气缸的燃烧室之内被扭紧。塞子用他们之間的一个小缝隙包含两个电极。当塞子受到火花当做冲动被引起的经销商的一种高压的冲动跳跃这两个电极之間的缝隙。这火花在燃烧室中点燃汽油-空气的混合。

3. 冷却和润滑

在发动机的混合的燃烧自然地作很多热,而且发动机不能被允许变成过热。冷却系统的功能将控制这热。

发动机可能是被冷却的水或空气,但是巨大的多数是被冷却的水。水穿戴在盈余上面围住气缸精选的水夹克从发动机和热的水上升加热。它然后流通过暖器炉,它越过暖器炉管,和回返被空气的通道冷却到水夹克的底部。一个狂热者,从发动机活塞总成被驱使,藉由经过暖器炉以低速增加气流协助冷却。一个泵可能被用来帮助流通水。

发动机也一定被禁止赛跑太凉爽的因此水的温度通常在特定极限里面被即是一个自动调温器的装置的行动所控制。这喝不同水的循环的效果以便,举例来说,当发动机首先被启动比较少的水被允许流通和发动机很快地作准备动作。

冷却系统能,当然,冻结在非常寒冷的天气方面上面,和这能造成相当多的损害。对于这理由,增加好防冻剂解决是适当的,在那之上能被留在到处将会在冬天避免冻结而且使系统免于腐蚀所有的年回合的夏天。

润滑系统

润滑是必需的让两个主要部份理由在发动机中减少摩擦而且穿着,和帮助拿走是从活塞总成和凸轮轴考虑进曲桥箱,从活塞的支座加热,而且从另一个工作分开。此外,它帮助活塞戒指在燃烧瓦斯中封闭,阻止他们进入气缸之内逃脱向下。(这些活塞戒指是被适合在每个活塞的顶端周围的凹槽的戒指。) 多数发动机有什么即是 " 力量饲养 ", 或压力,润滑系统。曲桥箱的底部被一个张-金属的平锅,或’污水坑’附上。这经过用了油支撑发动机润滑油而且有一个排水沟塞子可能被排出沟外离开。一个泵拉污水坑的油而且经过一个过滤器抽它和透过通道当时,呼叫’油方法’,对活塞总成的支座和凸轮轴,以及对气门齿轮。同时,从支座流动的油在曲桥箱中形成油雾,而且这雾润滑气缸墙壁。

一个警告的光或油因系统的油的压力而控制的标准度量通常被提供,以便当系统没有在动作,而且油没有在适当地流通时,驾驶员将会知道。如果系统没有在适当地动作工作部份可能抓住在而且上面造成对汽车发动机的严重伤害。它因此,是必要的让驾驶员停止发动机一旦他见到被发生的他的警告光就。

4. 制动

制动功能藉由在摩擦中吸收,能源根据感人的汽车持有。在如此做他们把能源转换成热。

有制动的两类型、鼓制动和圆盘制动。或或两者的类型可能被适合,但是哪里两者的类型被用圆盘制动装配在前面的轮子是平常的。

鼓刹

鼓制动有在一个固定的后面碟子上被展开而且被位于进一面鼓的一双半圆

制动鞋子。这鼓被修理到道路轮子而且以它替换。每只鞋的一端在一个枢上,而且一个春天支撑与水力气缸的活塞接触的另一端。(为了要使被鞋子发挥的压力相等,在前面的制动中,使用两个水力的气缸是平常的。见图 4 。) 每只鞋高度地面对材料,像是生产的制动衬里,磨擦力抵抗。

水力的系统包含一个主人的气缸和在路上是气缸轮子的奴隶气缸。奴隶气缸因装管和整个的系统而连接到主人气缸充满水力的液体。在主人的气缸的一个活塞被连接到制动踏板,所以当驾驶员沮丧时。踏板液体被挤出到每个奴隶气缸而且操作他们的活塞。液体从他们的气缸推动活塞。他们,依次,对抗制动鞋子的内部结束推动而且对抗每个轮子的煞车鼓强迫他们。我们说制动是开的。对抗鼓,被修理到道路轮子,的鞋子的这一个摩擦减慢或者停止汽车。当做制动脚的被允许发生,水力的液体回返到它的最初位置,活塞撤回,和春天附件对每个制动蹄片也归还它到它的最初位置,免于煞车鼓。现在我们说制动取消。

制动也可能由机械的连合从脚踏板和手刹杠杆所操作。常见的做法将操作两者都从和后面的制动水力地以一个中级的机械系统操作后面只有从手杠杆刹。水力操作的棒利益之一是系统自我平衡,意谓相同的压力在所有的四制动自动地被生产,然而机械的连合必须非常小心地为平衡被调整。当然,如果较多的压力被穿上制动之一超过在其余者上那里-是一种汽车将会制动的危险。

在后面的制动上操作的机械的连合是一个竿的系统或电缆把手刹杠杆连结

到制动蹄片机制,工作完全地独立地水力系统。

鼓制动倾向于刹努力的减少,像是由衬里的过热和鼓所引起的 " 褪色 " 。衰弱能影响所有的或者只有一些制动每次,但是它不长备,而且完全的效率像制动一样地很快返回冷却下来。然而,时尚不可能发生除了在制动已经重复地被用于之后之外减慢一个高速的汽车或在不断地刹向下一个险峻的小山之后。降如此的一个小山,使用藉由进入一个较低的齿轮之内变更向下刹的发动机会是较好的。鼓制动能被做比较不俯伏藉由改良冷却安排褪色,藉由为较多的空气安排在他们之上被偏斜,举例来说。

圆盘式制动器

圆盘制动用被奴隶水力的气气缸操作的摩擦填补有一个钢圆盘。钢的圆盘被附上到道路轮子而且以它替换。这一个钢圆盘的一部份在卡钳中被附上。(见图 5) 这一卡钳包含两个摩擦填补,一在圆盘和两个水力的气气缸的每边上,一在每个填补之外。填补通常在一个春天之前分别地被拿着,但是当驾驶员使制动踏板萧条时,水力的气气缸的活塞强迫对抗圆盘的边的填补。因为圆盘没被附上所有的方式回合,热产生了制动何时被应用比它更加快地非常被消散。这意谓圆盘制动更不倾向于褪色胜于鼓制动。

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