汽車工程專業(yè)英語(2.1-2.4).ppt

1、2.1 Principle of Operation 2.2 Engine Block and Cylinder Head 2.3 Piston, Connecting Rod and Crankshaft 2.4 Engine and Transmission Mounting 2.5 Valve System 2.1 工作原理 2.2 發(fā)動(dòng)機(jī)體和氣缸蓋 2.3 活塞、連桿和曲軸 2.4 發(fā)動(dòng)機(jī)和變速器組件 2.5 氣門系統(tǒng),Chapter 2 Internal Combustion Engine,2.6 Gasoline Fuel System 2.7 Diesel Engine 2.8

2、Engine Cooling 2.9 Engine Lubrication 2.10 Emission 2.6 汽油燃料系統(tǒng) 2.7 柴油發(fā)動(dòng)機(jī) 2.8 發(fā)動(dòng)機(jī)的冷卻 2.9 發(fā)動(dòng)機(jī)的潤(rùn)滑 2.10 排放,第二章 內(nèi)燃機(jī),Chapter 2 Internal Combustion Engine,2.1 Principle of Operation 2.1.1 Energy and power: Energy is used to produce power. The chemical energy in fuel is converted to heat by the burning of t

3、he fuel at a controlled rate. This process is called combustion. 21 工作原理 211 能源和動(dòng)力 能源用于產(chǎn)生動(dòng)力。燃料以控制的速率燃燒，燃料中的化學(xué) 能轉(zhuǎn)換為熱能。這個(gè)過程叫做燃燒。,Chapter 2 Internal Combustion Engine,If engine combustion occurs within the power chamber, the engine is called an Internal combustion Engine. If engine takes place outside

4、the cylinder, the engine is called an external combustion engine. 如果發(fā)動(dòng)機(jī)燃燒發(fā)生在動(dòng)力室內(nèi)，這種發(fā)動(dòng)機(jī)叫做內(nèi)燃機(jī)。 如果燃燒發(fā)生在氣缸外，這樣的發(fā)動(dòng)機(jī)叫做外燃發(fā)動(dòng)機(jī)。,Chapter 2 Internal Combustion Engine,Engines used in automobiles are internal combustion heat engines. Heat energy released in the combustion chamber raises the temperature of the c

5、ombustion gases within the chamber. 汽車使用的發(fā)動(dòng)機(jī)是內(nèi)燃熱發(fā)動(dòng)機(jī)。在燃燒室內(nèi)釋放的熱能 提高了室內(nèi)燃燒氣體的溫度。,Chapter 2 Internal Combustion Engine,The increase in gas temperature causes the pressure of the gases to increase. The pressure developed within the combustion chamber is applied to the head of a piston to produce a usable

6、mechanical force, which is then converted into useful mechanical power. 氣體溫度的增加使氣體的壓力增加。在燃燒室內(nèi)產(chǎn)生的壓力 作用于活塞的頂部，產(chǎn)生機(jī)械力，這個(gè)力轉(zhuǎn)換成有用的機(jī)械 動(dòng)力。,Chapter 2 Internal Combustion Engine,2.1.2 Engine terms Linking the piston by a connecting rod to a crankshaft causes the gas to rotate the shaft through half a turn. The

7、 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; 活塞通過連桿和曲軸連接，使得氣體帶動(dòng)曲軸旋轉(zhuǎn)半圈。作功 沖程耗盡了所有的氣體，這樣就必須采取相應(yīng)的措施排出廢氣 以及向氣缸內(nèi)充入新鮮的可燃混合氣：氣體的運(yùn)動(dòng)由氣門來控 制.,Chapter 2 Internal

8、 Combustion Engine,2.1.2: Engine Terms TDC（top dead center）: the position of the crank and piston when the piston is farther away from the crankshaft. BDC（bottom dead center）: the position of the crank and piston when the piston is nearest away from the crankshaft.,Chapter 2 Internal Combustion Engi

9、ne,Chapter 2 Internal Combustion Engine,swept volume: the volume between TDC and BDC. Clearance volume: the volume of space above the piston when it is at TDC. Engine capacity: this is the swept volume of all cylinders.,Chapter 2 Internal Combustion Engine,2.1.3: The four strokes Spark-ignition Engi

10、ne cycle Intake (induction) stroke Compression stroke Power stroke Exhaust stroke,Chapter 2 Internal Combustion Engine,Chapter 2 Internal Combustion Engine,2.1.4:Engine Overall Mechanics Crankshaft and connecting rods system Valve system Fuel system Ignition system Cooling system Lubrication system

11、Starting system,2.2： Engine block and cylinder head,Chapter 2 Internal Combustion Engine,2.2.1: Engine block: 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 als

12、o holds the crankshaft, which fastens to the bottom of the block. 氣缸體是發(fā)動(dòng)機(jī)的基體。發(fā)動(dòng)機(jī)其它的部件都安裝在缸體內(nèi)或 固定在缸體上，它包容了氣缸、水套和油道，以及固定在缸體 底部的曲軸等。,Chapter 2 Internal Combustion Engine,2.2.1: Engine block: The camshaft also fits inside the block, except on overhead-cam engine (OHC). In most cars, this block is made o

13、f gray iron, or an alloy (mixture) of gray iron and other metals, such as nickel or chromium. Engine blocks are casting.,Chapter 2 Internal Combustion Engine,2.2.1: Engine block: Some engine block, especially those in smaller cars, are made of cast aluminum. This metal is much lighter than iron. How

14、ever, iron wears better than aluminum. Therefore, the cylinders in most aluminum engine are lined with iron or steel sleeves. These sleeves are called cylinder sleeves. Some engine blocks are made entirely of aluminum.,Chapter 2 Internal Combustion Engine,2.2.1: Engine block:,Chapter 2 Internal Comb

15、ustion Engine,2.2.2: Cylinder sleeve: The dry sleeve can be cast in or pressed into a new block or used to recondition badly worn or damaged cylinders that cannot easily be rebored. 干式缸套可以鑄進(jìn)或壓入新氣缸體中， 或者用于嚴(yán)重磨損或損 壞而又不易重鏜的缸體的修復(fù)。,Chapter 2 Internal Combustion Engine,2.2.3: Cylinder head: The cylinder he

16、ad 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. 氣缸蓋扣在缸體的頂部，就像屋頂安在房子上一樣。缸蓋的下 方和活塞

17、頂部形成燃燒室。輕型車的直列發(fā)動(dòng)機(jī)所有缸僅有一 個(gè)氣缸蓋，較大的直列發(fā)動(dòng)機(jī)有兩個(gè)或更多缸蓋。,Chapter 2 Internal Combustion Engine,The cylinder head carries the valves, valve springs and the rockers on the rocker shaft, this part of the valve gear being worked by push- rods. 缸蓋上有氣門、氣門彈簧和搖臂軸上的搖臂，推桿推動(dòng)這部 分氣門傳動(dòng)機(jī)構(gòu)工作。,Chapter 2 Internal Combustion Eng

18、ine,Chapter 2 Internal Combustion Engine,2.2.4:Gasket,Chapter 2 Internal Combustion Engine,2.2.5: Oil pan or Sump: The oil pump in the lubricating system draws oil from the oil pan and sends it to all working parts in the engine. Theoil drains off and runs down into the pan. Thus, there is constant

19、circulation of oil between the pan and the working parts of the engine. 潤(rùn)滑系的機(jī)油泵從油底殼抽出機(jī)油，并把機(jī) 油輸送給發(fā)動(dòng)機(jī)的所有工作部件。機(jī)油從油 底殼流進(jìn)流出。因而在油底殼和發(fā)動(dòng)機(jī)的工 作部件之間有機(jī)油定向循環(huán)流動(dòng)。,Chapter 2 Internal Combustion Engine,2.3: Piston, connecting Rod and Crankshaft,Chapter 2 Internal Combustion Engine,2.3.2: Piston assembly Most pistons

20、 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. 大多數(shù)活塞由鋁鑄造而成。 通過連桿，活塞把可燃混合 氣燃燒所產(chǎn)生的力傳遞給曲 軸，并帶動(dòng)曲軸旋轉(zhuǎn)。,Chapter 2 Internal Combustion Engine,1.Piston,Chapter 2 Internal Combust

21、ion Engine,2. Piston Rings In modern engines, each piston has three rings. (Piston in older engines sometimes had four rings, or even five.) The inside surface of the ring fits in the groove on the piston The rings outside surface presses against the cylinder walls. 在新型發(fā)動(dòng)機(jī)上，每個(gè)活塞有三個(gè)活塞環(huán)。（在老式發(fā)動(dòng)機(jī) 上，每個(gè)活塞

22、有四個(gè)甚至五個(gè)活塞環(huán)。）環(huán)的內(nèi)邊面緊貼在活 塞的環(huán)槽里，環(huán)的外表面緊壓在氣缸壁上。,Chapter 2 Internal Combustion Engine,3. Piston Pin,Chapter 2 Internal Combustion Engine,2.3.3 Connecting Rod 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

23、 the connecting rod fit the crankshaft journal. This is called the big end. 連桿小頭與活塞銷連接，小頭孔處壓有諸如青銅這種較軟材料 所制成的襯套，連桿下端連接在曲軸的連桿軸徑處，稱為連桿 大頭。,Chapter 2 Internal Combustion Engine,Connecting Rod,Chapter 2 Internal Combustion Engine,Connecting Rod,Chapter 2 Internal Combustion Engine,2.3.4 Crankshaft,Chapte

24、r 2 Internal Combustion Engine,2.3.5 Cylinder number and firing order: Crank arrangement of engines: four cylinders six cylinders,Chapter 2 Internal Combustion Engine,Cylinder number and firing order: No.4 piston is always performing thecompanion stroke to No.1: when the inlet valve in No.4 cylinder

25、 is fully open, No.1 cylinder inletvalve is fully closed - this feature is useful to remember when checking valve clearances. 注意4號(hào)活塞和1號(hào)活塞總是成對(duì)運(yùn)行：4號(hào)氣缸進(jìn)氣門全閉 時(shí)，1號(hào)氣缸進(jìn)氣門全開這個(gè)特點(diǎn)在檢查氣門間隙時(shí)是很有 用的。,Chapter 2 Internal Combustion Engine,2.3.6 Flywheel,Chapter 2 Internal Combustion Engine,2.3.7 Torsional vibration

26、balancer: 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. 當(dāng)一缸點(diǎn)火時(shí)，使曲軸擺幅的速度提高，而其它軸的慣性阻礙 它，使其滯后，從而導(dǎo)致曲軸扭轉(zhuǎn)。,Chapter 2 Internal Combustion Engine,The inertia ring is bonded t

27、o the hub through a flexible elastomer (rubber compound) insert. The inertial ring moves slightly in relation to crankshaft rotation as each cylinder fires, thereby dampening the torsional vibration of the crankshaft over a wide range of engine speed. 慣性盤通過一層由橡膠合成的可變形人造橡膠層與減振器圓盤 相連在每個(gè)汽缸點(diǎn)火時(shí)，慣性盤相對(duì)于曲軸運(yùn)

28、動(dòng)做微小轉(zhuǎn) 動(dòng)，用以削減發(fā)動(dòng)機(jī)較大速度范圍.,Chapter 2 Internal Combustion Engine,Chapter 2 Internal Combustion Engine,汽車英語專業(yè)詞組 2.1 chemical energy 化學(xué)能 internal combustion engine 內(nèi)燃機(jī) inlet valve 進(jìn)氣閥 exhaust valve 排氣閥 TDC 上止點(diǎn) BDC 下止點(diǎn) swept volume 有效/工作容積 engine capacity 發(fā)動(dòng)機(jī)排量 clearance volume 燃燒室容積 compression ratio 壓縮比,Chapter 2 Internal Combustion Engine,汽車英語專業(yè)詞組 2.1 kinetic energy 動(dòng)能 induction/i