外文翻譯--汽車懸架工作原理

1、<p><b>　　附錄3</b></p><p><b>　　英文原文</b></p><p>　　How Car Suspensions Work</p><p>　　By William Harris</p><p>　　University of Michigan</p>

2、;<p>　　When people think of automobile performance, they normally think of horsepower, torque and zero-to-60 acceleration. But all of the power generated by a piston engine is useless if the driver can't contr

3、ol the car. That's why automobile engineers turned their attention to the suspension system almost as soon as they had mastered the four-stroke internal combustion engine. </p><p>　　The job of a car susp

4、ension is to maximize the friction between the tires and the road surface, to provide steering stability with good handling and to ensure the comfort of the passengers. In this article, we'll explore how car suspensi

5、ons work, how they've evolved over the years and where the design of suspensions is headed in the future. </p><p>　　Vehicle Dynamics If a road were perfectly flat, with no irregularities, suspensions w

6、ouldn't be necessary. But roads are far from flat. Even freshly paved highways have subtle imperfections that can interact with the wheels of a car. It's these imperfections that apply forces to the wheels. Accor

7、ding to Newton's laws of motion, all forces have both magnitude and direction. A bump in the road causes the wheel to move up and down perpendicular to the road surface. The magnitude, of course, depen</p><

8、;p>　　Without an intervening structure, all of wheel's vertical energy is transferred to the frame, which moves in the same direction. In such a situation, the wheels can lose contact with the road completely. Then

9、, under the downward force of gravity, the wheels can slam back into the road surface. What you need is a system that will absorb the energy of the vertically accelerated wheel, allowing the frame and body to ride undist

10、urbed while the wheels follow bumps in the road. </p><p>　　The study of the forces at work on a moving car is called vehicle dynamics, and you need to understand some of these concepts in order to appreciate

11、 why a suspension is necessary in the first place. Most automobile engineers consider the dynamics of a moving car from two perspectives: </p><p>　　Ride - a car's ability to smooth out a bumpy road </

12、p><p>　　Handling - a car's ability to safely accelerate, brake and corner </p><p>　　These two characteristics can be further described in three important principles - road isolation, road holdi

13、ng and cornering. The table below describes these principles and how engineers attempt to solve the challenges unique to each. </p><p>　　A car's suspension, with its various components, provides all of t

14、he solutions described. </p><p>　　Let's look at the parts of a typical suspension.</p><p>　　The Chassis The suspension of a car is actually part of the chassis, which comprises all of the

15、important systems located beneath the car's body. </p><p>　　These systems include: </p><p>　　The frame - structural, load-carrying component that supports the car's engine and body, whic

16、h are in turn supported by the suspension </p><p>　　The suspension system - setup that supports weight, absorbs and dampens shock and helps maintain tire contact </p><p>　　The steering system -

17、mechanism that enables the driver to guide and direct the vehicle </p><p>　　The tires and wheels - components that make vehicle motion possible by way of grip and/or friction with the road </p><p&

18、gt;　　So the suspension is just one of the major systems in any vehicle. </p><p>　　With this big-picture overview in mind, it's time to look at the three fundamental components of any suspension: springs,

19、 dampers and anti-sway bars. Springs Today's springing systems are based on one of four basic designs: Coil springs This is the most common type of spring and is, in essence, a heavy-duty torsion bar coiled arou

20、nd an axis. Coil springs compress and expand to absorb the motion of the wheels. </p><p>　　Leaf springs - This type of spring consists of several layers of metal (called "leaves") bound together to

21、 act as a single unit. Leaf springs were first used on horse-drawn carriages and were found on most American automobiles until 1985. They are still used today on most trucks and heavy-duty vehicles. </p><p>

22、　　Torsion bars - Torsion bars use the twisting properties of a steel bar to provide coil-spring-like performance. This is how they work: One end of a bar is anchored to the vehicle frame. The other end is attached to a w

23、ishbone, which acts like a lever that moves perpendicular to the torsion bar. When the wheel hits a bump, vertical motion is transferred to the wishbone and then, through the levering action, to the torsion bar. The tors

24、ion bar then twists along its axis to provide the spring force</p><p>　　Air springs - Air springs, which consist of a cylindrical chamber of air positioned between the wheel and the car's body, use the c

25、ompressive qualities of air to absorb wheel vibrations. The concept is actually more than a century old and could be found on horse-drawn buggies. Air springs from this era were made from air-filled, leather diaphragms,

26、much like a bellows; they were replaced with molded-rubber air springs in the 1930s. </p><p>　　Based on where springs are located on a car -- i.e., between the wheels and the frame -- engineers often find it

27、 convenient to talk about the sprung mass and the unsprung mass. </p><p>　　Springs: Sprung and Unsprung Mass</p><p>　　The sprung mass is the mass of the vehicle supported on the springs, while t

28、he unsprung mass is loosely defined as the mass between the road and the suspension springs. The stiffness of the springs affects how the sprung mass responds while the car is being driven. Loosely sprung cars, such as l

29、uxury cars (think Lincoln Town Car), can swallow bumps and provide a super-smooth ride; however, such a car is prone to dive and squat during braking and acceleration and tends to experience body sway or </p><

30、p>　　So, while springs by themselves seem like simple devices, designing and implementing them on a car to balance passenger comfort with handling is a complex task. And to make matters more complex, springs alone can&

31、#39;t provide a perfectly smooth ride. Why? Because springs are great at absorbing energy, but not so good at dissipating it. Other structures, known as dampers, are required to do this. </p><p>　　Dampers: S

32、hock AbsorbersUnless a dampening structure is present, a car spring will extend and release the energy it absorbs from a bump at an uncontrolled rate. The spring will continue to bounce at its natural frequency until al

33、l of the energy originally put into it is used up. A suspension built on springs alone would make for an extremely bouncy ride and, depending on the terrain, an uncontrollable car. </p><p>　　Enter the shock

34、absorber, or snubber, a device that controls unwanted spring motion through a process known as dampening. Shock absorbers slow down and reduce the magnitude of vibratory motions by turning the kinetic energy of suspensio

35、n movement into heat energy that can be dissipated through hydraulic fluid. To understand how this works, it's best to look inside a shock absorber to see its structure and function. </p><p><b>　　附

36、錄4</b></p><p><b>　　英文翻譯</b></p><p><b>　　汽車懸架工作原理</b></p><p>　　William Harris</p><p><b>　　密歇根大學</b></p><p>　　當人們想到

37、汽車性能時，他們通常想起的是馬力，扭矩，0到60加速時間。但是，如果司機無法控制汽車，所有的由活塞式發(fā)動機產生的功率是無用的。這就是為什么汽車的工程師就在他們幾乎已經掌握了四沖程內燃機時把他們的注意力轉向了懸掛系統(tǒng)。</p><p>　　圖1 Honda Accord 2005 Coupe雙橫臂汽車懸架</p><p>　　汽車懸架的工作是最大化的充分利用輪胎和路面之間的摩擦，以提供良好的

38、操縱穩(wěn)定性，以確保乘客的舒適性。在這篇文章中，我們將探討汽車懸架是如何工作的，它們這些年經過的發(fā)展以及未來懸架設計的發(fā)展方向。</p><p><b>　　汽車動力學</b></p><p>　　如果道路是完全平坦的，沒有異常的情況，懸架系統(tǒng)就不是必要的。但道路往往都不是平坦的，即使是剛鋪好的公路有細微的缺陷，也能夠與汽車的車輪相互作用。它的這些缺陷聚集于車輪。根據牛

39、頓運動定律，所有的力都有大小和方向。道路上的撞擊導致的車輪垂直上下相對于路面移動。當然大小，取決于車輪是在撞擊一個巨大的凸起還是一個微小的斑點。無論哪種方式，汽車輪轂出現的垂直加速度，是由于它通過一個路面的缺陷。</p><p>　　若沒有中間的結構，所有車輪的垂直能量都被轉移到在同方向上移動車架上。在這樣的情況下，車輪可以完全與路面失去接觸。然后，在向下的重力下，車輪可以返回路面。你需要的是一個能夠吸收車輪垂直

40、加速能量的系統(tǒng)，使車架和車身在車輪沿顛簸的道路行駛時不受干擾。</p><p>　　對開動的汽車的工作動力的研究稱為汽車動力學研究，你需要了解其中的一些概念，以明白為什么懸架系統(tǒng)的重要性是首位的。大多數汽車工程師從兩個角度考慮一個行駛中的汽車的動態(tài)特征：</p><p>　　行駛 ——一輛汽車行駛出坎坷道路的能力</p><p>　　操縱 ——一輛汽車安全地加速，剎

41、車和過角落的能力</p><p>　　圖2 懸掛運動參數示意圖 </p><p>　　這兩個特點可以進一步說明在三個重要原則——道路隔離，道路附著和轉彎。下表描述了這些原則和工程師試圖解決的各不相同的挑戰(zhàn)(表略)。</p><p>　　汽車的懸掛系統(tǒng)通過它的各個組成部分，提供所有的解決方案。</p><p>　　讓我們看一個典型的懸架系統(tǒng)。&

42、lt;/p><p><b>　　底盤系統(tǒng)</b></p><p>　　一輛汽車的懸掛，其實就是在底盤，其中包括所有該車的車身下方的的重要系統(tǒng)。</p><p><b>　　這個系統(tǒng)包括</b></p><p>　　車架——結構、承載組件，支持汽車的引擎和車身，它們反過來又受懸架的支持</p>

43、<p>　　懸掛系統(tǒng)——承載負荷，吸收和削弱沖擊力，并幫助維持輪胎與地面的接觸</p><p>　　轉向系統(tǒng)——使司機指引車輛的機械系統(tǒng)</p><p>　　輪胎和輪轂——通過與路面的抓地力和/或摩擦力使車輛的運動方式可行的組件</p><p>　　因此，懸架系統(tǒng)是任何車輛的一個主要系統(tǒng)。</p><p>　　考慮到這個大圖的概

44、述，讓我們看看汽車懸架系統(tǒng)的三個主要組成部分：彈簧、減震器和防搖桿。</p><p><b>　　彈簧</b></p><p>　　如今的彈簧系統(tǒng)基于四個不同的基本設計理念：</p><p>　　線圈彈簧——這是彈簧的最常見的類型，實質上是重型扭桿圍繞一個軸圈。線圈彈簧的壓縮與伸長吸收了車輪的運動能量。</p><p>

45、　　鋼板彈簧——這個彈簧型的多層金屬稱為“簧片”聯系在一起作為一個獨立的單元。鋼板彈簧首先應用于馬車且在1985年的美國汽車上已經普及了。它們至今仍應用于大部分卡車和重型車輛。</p><p>　　扭力桿——扭力桿使用一種扭鋼筋的性能提供線圈彈簧般的表現。它們的工作原理是：桿的一端被固定到車身框架。另一端連接到一個橫臂，它就像一個杠桿，移動垂直扭力桿。當車輪有一個碰撞時，垂直的運動傳到橫臂，然后通過翹起扭力桿，之

46、后扭力桿通過其軸線曲折提供彈簧力。歐洲的汽車制造商廣泛地使用該系統(tǒng)，就像上世紀50、60年代的美國惠普與克萊斯勒公司一樣。</p><p>　　空氣彈簧——空氣彈簧，它是在車輪和車體之間的由圓柱形空氣腔組成的，它使用壓縮空氣的質量來吸收車輪的震動。這一概念其實可以在一個多世紀前的馬拉車上發(fā)現。它從這個時代是從充氣、皮革隔膜而來，就像是一個風箱。它們是從20世紀30年代被橡膠澆筑空氣彈簧所取代的。</p>

47、;<p>　　基于彈簧是安裝在車上——即車輪和車架之間——工程師們經常將它們簡單分為簧載質量與簧下質量。</p><p>　　彈簧：簧載質量和簧下質量</p><p>　　簧載質量是彈簧支撐的汽車質量，而簧下質量粗略的定義為道路和懸架彈簧之間的質量。當汽車被驅動時，彈簧的剛度對懸掛質量的響應有影響。松散彈簧的汽車，例如豪華轎車(認為林肯城市汽車)，可以平穩(wěn)的渡過顛簸路面并且提

48、供一個超級平順的車程。但是，這樣的車很容易熄火，突然制動以及加速時車身容易側偏和轉彎。緊的彈簧汽車，如跑車(認為馬自達的Miata)，在顛簸的道路上，它們可以減弱車身的震動，這意味著它們可以更活躍更靈動即便是在死角轉彎時。</p><p>　　因此，雖然看起來本身很簡單的彈簧裝置，設計并將其置于車上來保持乘客的舒適度在一個可控制的范圍內卻是一項復雜的任務。使事情更加復雜的是，僅憑彈簧是不足以提供一個完美的平穩(wěn)的行

49、程的。為什么？那是因為彈簧雖然能夠吸收巨大的能量，但它在散熱上卻算不上良好。其他的結構，就如眾所周知的阻尼器，要求做到這一點。</p><p><b>　　阻尼減震器</b></p><p>　　除非抑制結構的存在，汽車彈簧將伸長并且釋放出在吸收的速度失控時碰撞產生的能量。彈簧繼續(xù)以其自然頻率反彈，直至其所有的最初的能量用盡。建立一個單獨的彈簧懸架會使行程非常的有彈性

50、，并且不受地形控制的汽車。</p><p>　　輸入減震器和緩沖器，一個裝置，通過控制一個不期望的彈簧運動的過程如同阻尼。用減震器減慢和減少運動振動的幅度，通過懸架運動的動能轉化為熱能，能量可以通過液壓流體消散。要理解這是如何工作的，最好找一個減震器的內部結構圖來看它的結構和功能。</p><p>　　減震器基本上就是一個安裝在車架與輪轂之間的油泵。部件上部安裝的連接到車架(即簧載質量)，

51、而較低的安裝連接到車軸，靠近輪(即簧下的質量)。在雙管式設計中，一種最常見類型的減震器結構是，上部連接在活塞桿上，而活塞桿又是依次連接活塞的，同時它們又坐在充滿液壓油的管中。內管被稱為壓力管，外管就是我們所知道的儲備管。儲備管會儲存多余的液壓油。</p><p>　　當汽車車輪在路面上遇到碰撞，造成彈簧線圈卷和開，彈簧的能量通過上部分轉移到減震器，向下沿著活塞桿進入活塞。節(jié)流孔將活塞穿孔并且當活塞在壓力管中上下移

52、動時使液體能夠傾流出來。由于孔比較小，只有少量的液體在很大的壓力下能夠通過。這使活塞減速，從而減慢彈簧的速度。</p><p>　　減震器工作在兩個周期 - 壓縮循環(huán)和延長周期。壓縮循環(huán)時活塞向下移動，壓縮在活塞下面的腔室中的液壓流體。延長周期時活塞移向壓力管的頂部，壓縮在活塞上方的腔室中的流體。一個典型的汽車或輕型卡車在延長周期時比它們在壓縮循環(huán)時將要受到更大的阻力?？紤]到這一點，在壓縮循環(huán)時控制車輛的簧下重量

53、的運動，而延長周期控制更重一些的簧載重量。</p><p>　　所有現代的減震器都是速度敏感型的——懸架移動得越快，減震器提供的阻力越多。這使得沖擊可以適應道路的狀況并且將一些汽車行駛過程中不期望發(fā)生的情況包括反彈，搖擺，制動潛水和加速蹲等控制住。</p><p>　　阻尼器：支桿和穩(wěn)定桿</p><p>　　另一種常見的阻尼結構是支桿——基本上是一個內部裝有螺旋彈

54、簧的減震器。它執(zhí)行兩項工作：它們提供減震器的減震作用，并且它們?yōu)槠噾壹芟到y(tǒng)提供支撐結構。這意味著支柱提供的超過減震器，減震器不支持車輛的重量——它們只控制重量在汽車內轉移的速度，而不是重量本身。</p><p>　　正是因為沖擊和支桿與汽車的操控有這么大的關系,它們被認為是關鍵的安全功能。過度磨損的沖擊和支柱可以讓車輛的重量從一側轉移到另一側也可以從前方到后方。這降低了輪胎的抓地能力，以及處理和制動性能。<

55、;/p><p><b>　　穩(wěn)定桿</b></p><p>　　穩(wěn)定桿(也稱為防傾桿)與減震器或支柱一起使用，給行駛中的汽車額外的穩(wěn)定性。穩(wěn)定桿是一個金屬棒，它橫跨整個車軸并且將兩端的懸架的有效地連接在了一起。</p><p>　　當將懸架在一個車輪上上下移動時，穩(wěn)定桿將運動傳遞到另一個車輪。這將創(chuàng)造一個更平穩(wěn)的車程，并減少車輛的晃動。特別是，它能