汽車專業(yè)英語第二章

1、CHAPTER 2 INTERNAL COMBUSTION ENGINE combustion kmbsn n.燃燒燃燒 stroke strouk n.沖程沖程 piston pistn n.活塞活塞 cylinder silind n.氣缸氣缸 valve vlv n.氣門，閥門，閥氣門，閥門，閥 exhaust igz:st n.排氣，廢氣排氣，廢氣 intake inteik n.進(jìn)氣，進(jìn)（引，吸）入進(jìn)氣，進(jìn)（引，吸）入 compression kmpren n.壓縮壓縮 crankshaft krk:ftn.曲軸曲軸 swirl sw:l n.漩渦，渦流，紊流；漩渦，渦流，紊流；v.

2、渦動(dòng)渦動(dòng) churn t:n v.攪拌，攪動(dòng)攪拌，攪動(dòng) foundation faundein n.基礎(chǔ)，基地，基金，基礎(chǔ)，基地，基金，機(jī)座機(jī)座 camshaft km:ftn.凸輪軸凸輪軸 accessory ksesrin.附屬品，附件，輔助裝附屬品，附件，輔助裝置置 clutch kltn.離合器離合器 housing hauzi n.外殼外殼 bolt boult n.螺栓；螺栓；v.用螺栓連接用螺栓連接 core k: n.芯，核心，鐵心，型芯，沙芯，（電芯，核心，鐵心，型芯，沙芯，（電纜）芯線纜）芯線 aluminum lju:minmn.鋁鋁 liner lainn.襯套，襯里，

3、襯板襯套，襯里，襯板 oscillate sileitv.振蕩，振動(dòng)，波動(dòng)，動(dòng)振蕩，振動(dòng)，波動(dòng)，動(dòng)搖搖 bearing b rin.軸承軸承 journal:nln.軸頸軸頸 throw roun.& v.投擲，扔；投擲，扔；n.投擲距離，投擲距離，偏心距離，擺幅；（偏心距離，擺幅；（pl.）曲柄）曲柄 attach tt v.附著，連接，固定（附著，連接，固定（to） reciprocating risiprkeitia.往復(fù)的往復(fù)的 mount muntv.安裝，固定；安裝，固定；n.安裝件，安裝件，支架，機(jī)座支架，機(jī)座 rim rimn.邊緣，輪緣，輪輞，齒圈邊緣，輪緣，輪輞，齒

4、圈 heat-resistant hi:t-rizistnt a.耐熱的耐熱的 clearance klirnsn.間隙間隙 lifter liftn.挺桿挺桿 carburetion k:bjurenn.汽化汽化 carburetor k:bjuretn.化油器化油器 internal combustion engine 內(nèi)燃機(jī)內(nèi)燃機(jī) four-stroke cycle 四沖程循環(huán)四沖程循環(huán) spark plug 火花塞火花塞 intake stroke 進(jìn)氣行程進(jìn)氣行程 power stroke 作功行程作功行程 compression stroke 壓縮行程壓縮行程 exhaust st

5、roke 排氣行程排氣行程 connecting rod 連桿連桿 insert bearing 鑲?cè)胧捷S承鑲?cè)胧捷S承 valve seat 氣門座氣門座 valve guide 氣門導(dǎo)管氣門導(dǎo)管 valve train 氣門機(jī)構(gòu)，氣門組氣門機(jī)構(gòu)，氣門組 hydraulic valve lifter 液力挺桿液力挺桿2.1: principle of operation 2.1.1: Energy and power: Engines used in automobiles are internal combustion heat engines. They convert the chemi

6、cal energy of the gasoline into heat within a power chamber that is called a combustion chamber. Heat energy released in the combustion chamber raises the temperature of the combustion gases within the chamber. The increase in gas temperature causes the pressure of the gases to increase. The pressur

7、e developed within the combustion chamber is applied to the head of a piston to produce a usable mechanical force, which is then converted into useful mechanical power. 2.1.2: Engine TermsTDC（top dead center）:The position of the crank and piston when the piston is farthest away from the crankshaft.B

8、DC（bottom dead center）:The position of the crank and piston when the piston is nearest away from the crankshaft.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.Compression

9、ration:(swept vol + clearancevol) / (clearance vol) Intake (induction) stroke Compression stroke Power stroke Exhaust strokeList the main systems of a gasoline engine List the main systems of a gasoline engine Crankshaft and connecting rods system 圖片圖片Valve system 圖片圖片F(xiàn)uel systemIgnition systemLubri

10、cation systemCooling systemStarting system 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 gas, so means must be provided to expel the burnt gas and recharge the cylinder with a fresh petrol-air mixture: this

11、 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。2.2：engine block and cylinder head 2.2.1Engine block: The engine block is the basic frame of the engine. All other engine parts either fit inside it or fasten to it.

12、It holds the cylinders, water jackets, and oil galleries. The engine block also 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。 2.2.2 Cylinder sleeve: The dry sleeve can be cast in or pressed into a new block or used to re

13、condition badly worn damaged cylinders that cannot easily be rebored. 干缸套可以鑄在或壓入新缸體中，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)。 2.2.3 Cylinder head: 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 piston. In-line engin

14、es 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。 The cylinder head carries the valves, valve springs and the rockers on the rocker shaft, this part of the valv

15、e gear being worked by push-rods. 缸蓋上安裝有氣門、氣門彈簧和搖臂軸上的搖臂，推桿推動(dòng)這些氣門傳動(dòng)機(jī)構(gòu)工作。 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. The oil drains off and runs down into the pan. Thus, there is constant circulation of oil

16、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)。2.3 piston, Connecting rod and crankshaftjournald:nl; d:nl n. 日志，日記，期刊 2.3.2 Piston assembly: Most pistons are made from cast aluminum. The piston, through the connecting rod,

17、 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)。 1.Piston : In diesel engines, the combustion chamber may be formed totally or in part in the piston crown, depending on method of injection. 柴油機(jī)

18、發(fā)動(dòng)機(jī)根據(jù)噴油方法不同，活塞頭部可以形成全部燃燒室，也可以是燃燒室的一部分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)

19、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)邊面緊貼在活塞環(huán)槽里，環(huán)的外表面緊壓在氣缸壁上。 裝配活塞環(huán)從上至下的順序：第一道環(huán)、第二道環(huán)、油環(huán)。 注意： A、在安裝時(shí)應(yīng)防止活塞和活塞環(huán)受損； B、安裝時(shí)有記號(hào)一面朝上。 C、裝好后，活塞環(huán)應(yīng)能自由轉(zhuǎn)動(dòng)。 D、頂環(huán)與第二道環(huán)的位置不能顛倒。 E、將活塞環(huán)開口相距隔開120度，不要重合。 F、安裝油環(huán)時(shí)，應(yīng)先安裝隔圈，然后再安裝側(cè)軌。 2.3.3 Connecting rod: The connecting rod little end is connected to the piston pin. A bu

20、sh made from a soft metal, such as bronze, is used for this joint. The lower end of the connecting rod fit the crankshaft journal. This is called the big end. n. 灌木叢，矮樹v. 叢生，(以灌木)標(biāo)記、保護(hù)、支撐n. 布什(姓氏)adj. 長(zhǎng)得低矮的n. 襯套vt. 加襯套于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。Cylinder number and firi

21、ng order: 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 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)氣門全開時(shí)，1號(hào)氣缸進(jìn)氣門全閉這個(gè)特點(diǎn)在檢查氣門間隙時(shí)是很有用的。no

22、ta bene.nut bi:ni Torsional Vibration 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.Inertia in:in.慣性,惰性當(dāng)一缸點(diǎn)火時(shí)，使曲軸的轉(zhuǎn)速提高，而其它軸的慣性阻礙它，使其滯后，從而導(dǎo)致曲軸扭轉(zhuǎn)。 The inertia

23、ring is bonded to 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.慣性環(huán) n. 中心，輪轂，輪軸人造橡膠 慣性盤通過一層由橡膠合成的

24、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)動(dòng)做微小轉(zhuǎn)動(dòng)，用以削減發(fā)動(dòng)機(jī)較大速度范圍內(nèi)的曲軸扭轉(zhuǎn)振動(dòng) 2.5: valve system Whats the main function of the Valve System? 1) Open and close the valves at just the right time. 2) Remove as much of the burned gases as is possible and increases volumetric efficiency. How many types of the Camshaft

25、Drive Mechanism? Camshaft km:ft n. 凸輪軸mechanismmeknizm; mek.nizm n. 機(jī)制，原理n. 結(jié)構(gòu)，機(jī)構(gòu)，機(jī)械裝置1-凸輪軸凸輪軸 2-挺柱挺柱 3-推桿推桿 4-搖臂軸搖臂軸 5-鎖緊螺母鎖緊螺母 6-調(diào)整螺釘調(diào)整螺釘 7-搖臂搖臂 8-氣門鎖夾氣門鎖夾 9-氣門彈簧座氣門彈簧座 10-氣門彈簧氣門彈簧 11-氣門導(dǎo)管氣門導(dǎo)管 12-氣門氣門 13-氣門座氣門座2.5 Valve System: 2.5.1 Valve Operation The cam is an egg-shaped piece of metal on a sha

26、ft that rotates in coordination with the crankshaft. The metal shaft, called the camshaft, typically has individual cams for each valve in the engine. As the camshaft rotates, the lobe, or high spot of the cam, pushes against parts connected to the stem of the valve. This action forces the valve to

27、move downward. This action could open an inlet valve for an intake stroke, or open an exhaust valve for an exhaust stroke. 凸輪是一個(gè)蛋形的金屬塊，它安裝在同曲軸協(xié)調(diào)運(yùn)轉(zhuǎn)的一根金屬軸上，該軸稱為凸輪軸，其上有同發(fā)動(dòng)機(jī)每一個(gè)氣門對(duì)應(yīng)的凸輪。當(dāng)凸輪軸旋轉(zhuǎn)時(shí)，凸輪的最高點(diǎn)，也就是凸圓，推動(dòng)連接氣門桿的部件，使得氣門向下運(yùn)動(dòng)，在進(jìn)氣沖程打開進(jìn)氣門，在排氣沖程打開排氣門。 In this arrangement, the cam lobes push against round me

28、tal cylinders called cam follower. As the lobe of the cam comes up under the cam follower, it pushes the cam follower upward (away from the camshaft). The cam follower rides against a push rod, which pushes against a rocker arm. The rocker arm pivots on a shaft through its center. As one side of the

29、 rocker arm moves up, the other side moves down, just like a seesaw. The downward-moving side of the rocker arm pushes on the valve stem to open the valve. 在這種方案中，凸輪基圓推動(dòng)圓形的金屬筒，也就是挺柱。凸輪凸圓運(yùn)動(dòng)到挺柱下方時(shí)，推動(dòng)挺柱遠(yuǎn)離凸輪軸向上運(yùn)動(dòng)。挺柱帶著推桿，推桿推動(dòng)搖臂，搖臂繞搖臂軸的中心轉(zhuǎn)動(dòng)。搖臂的一端升起，另一端就落下，這類似于蹺蹺板。搖臂向下運(yùn)動(dòng)的一端推動(dòng)氣門桿打開氣門。2.5.2 Valve clearance:

30、When the engine runs in compression stroke and power stroke, the valves must close tightly on their seats to produce a gas-tight seal and thus prevent the gases escaping from the combustion chamber. If the valves do not close fully the engine will not develop full power. Also the valve heads will be

31、 liable to be burnt by the passing hot gases, and there is the likelihood of the piston crown touching an open valve, which can seriously damage the engine. 當(dāng)發(fā)動(dòng)機(jī)在壓縮沖程和作功沖程工作時(shí)，氣門必須緊貼在氣門座上，形成良好的氣密性以防止燃燒室漏氣。如果氣門關(guān)閉不嚴(yán)，發(fā)動(dòng)機(jī)就不能發(fā)揮出全部的功率。而且氣門頭部容易被經(jīng)過的高溫氣體燒蝕，活塞頂部也可能會(huì)碰到氣門使發(fā)動(dòng)機(jī)嚴(yán)重?fù)p壞。 So that the valves can close fu

32、lly some clearance is needed in the operating mechanism. This means that the operating mechanism must be able to move sufficiently far enough away from the valve to allow the valves to be fully closed against its seat by the valve spring. However, if the clearance is set too great this will cause a

33、light metallic tapping noise. 所以在氣門傳動(dòng)機(jī)構(gòu)中要預(yù)留一些間隙使氣門得以完全關(guān)閉。這就是說，氣門傳動(dòng)機(jī)構(gòu)運(yùn)動(dòng)要與氣門有一個(gè)充分遠(yuǎn)的距離，使得氣門在氣門彈簧作用下緊閉氣門座?？墒侨绻g隙過大，會(huì)引起輕微的金屬敲打聲。 2.5.2 Valve Timing 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,

34、 the end of the exhaust stroke and the beginning of the intake stoke overlap for a short period of time. This is called valve overlap. Valve timing and valve overlap vary on different engines. 由上顯而易見，排氣門在進(jìn)氣門打開的一小段時(shí)間內(nèi)也開著。換句話說，排氣沖程終了和進(jìn)氣沖程初期有一小段時(shí)間的重疊（進(jìn)排氣門同時(shí)打開），這稱為氣門重疊。不同的發(fā)動(dòng)機(jī)，其配氣相位和氣門重疊是不一樣的。 Opening th

35、e intake valve before TDC and closing it after BDC increases the fill of air-fuel mixture in the cylinder. Opening the intake valve early helps overcome the static inertia of the air-fuel mixture at the beginning of the intake stroke, while leaving the intake valve open after BDC takes advantage of

36、the kinetic inertia of the moving air-fuel mixture. This increases volumetric efficiency. 在上止點(diǎn)前打開進(jìn)氣門和在下止點(diǎn)后關(guān)閉進(jìn)氣門可增加氣缸內(nèi)可燃混合氣的進(jìn)氣量。提前打開進(jìn)氣門有助于克服進(jìn)氣沖程初期（空氣）的靜止慣性，同時(shí)在下止點(diǎn)后打開進(jìn)氣門可充分利用可燃混合氣的運(yùn)動(dòng)慣性，這可增加容積效率（進(jìn)氣效率）。2.5.4 Cam Design and Control Dynamic The entire valve-train assembly can be viewed as a spring/mass sy

37、stem in which the conversion from stored to free energy causes forced vibration. Valve-train assemblies with overhead camshafts can be represented with sufficient accuracy by a 1-mass system (consisting of the moving mass, the valve-train assembly stiffness and corresponding damping). 整個(gè)氣門機(jī)構(gòu)可看成一個(gè)彈簧-質(zhì)量系統(tǒng)，其儲(chǔ)存的能量轉(zhuǎn)化為自由能量時(shí)會(huì)引起受迫振動(dòng)。帶有頂置凸輪軸的氣門機(jī)構(gòu)可非常精確地用單質(zhì)量系統(tǒng)來表示，由運(yùn)動(dòng)質(zhì)量、氣門機(jī)構(gòu)的剛度和相應(yīng)的阻尼組成。2.5.5 Camshaft drive mechanism: Each cam must revolve once during the four-stroke cycle to open a valve. A cycle, remember, corresponds with two