【正文】 II. Text Explanation ? main bearing journal ? rod journal ? crank arm ? counter balanced weight ? timing gear ? front and rear seals ? top dead center ? multicylinder engine ? bearing cap ? belt pulley III. Exercises ?Translate the following expressions into Chinese. ?主軸頸 ?連桿軸頸 ?曲柄 ?平衡重 ?正時齒輪 ?前后油封 ?上止點 ?多缸發(fā)動機 ?軸承 ?皮帶輪 III. Exercises cranking claw timing gear main bearing belt pulley tortional vibration damper flywheel flywheel bolt crankshaft ?The crankshaft , regarded as the “backbone ” of the engine, serves to change the reciprocating motion of the piston into rotary motion and handles the entire power output. The crankshaft is actually made up of various parts such as main bearing journal, rod journal, crank arm, counterbalanced weight and flywheel. The connecting rod links its large end to the crankshaft and its small end to the piston . III. Exercises ?I. Translate the following sentences into Chinese. ?1． The crankshaft, regarded as the “backbone” of the engine, serves to change the reciprocating motion of the piston into rotary motion and handles the entire power output. ?曲軸作為發(fā)動機的支柱，可將活塞的往復(fù)運動轉(zhuǎn)換成旋轉(zhuǎn)運動，并且將整個能量輸出。?dik] adj. ?周期的 ,周期性的 。 ?近義詞： act as..... ?區(qū)別： serve 為 …… 服務(wù) II. Text Explanation ? It may be flat, concave, and convex or any one of a great variety of shapes to promote turbulence or help control bustion. ?concave [?k?n?keiv] n. 凹 , 凹面 ?convex [?k?n?veks] ?adj. 表面彎曲如球的外側(cè) , 凸起的 ? 譯文 ：（活塞頂部）形狀可以是平頂、凹頂、凸頂或者其它各種形狀，這些形狀促進(jìn)紊流或有助于控制燃燒。 3 cylinder gasket。 II. Text Explanation ?Allow 使 … 成為可能，允許 ?近義詞： permit ?The windfall allowed me to buy a house. ?這意外之財使我 得以 購置一幢房子。 III. Exercises ? 汽車主要由四個部分組成，他們是：發(fā)動機、底盤、車身和電氣設(shè)備。 ?be posed of ?Navy must be posed of surface ship unit and submarine unit. ?海軍一定是由水面艦艇部隊和潛艇部隊組成。 2clutch。 II. Text Explanation ?Power is produced by the linear motion of a piston in a cylinder. ? linear [? lini?] adj. 線的 , 直線的 , 線 性的 ? piston [? pist?n] II. Text Explanation ?The piston attached to the top of a connecting rod by a pin, called a piston pin or wrist pin. ? attach to v. 連接 ?connecting rod 連桿 ? piston pin = wrist pin 活塞銷 II. Text Explanation ?The connecting rod transmits the upanddown motion of the piston to the crankshaft, which changes it into rotary motion. ?transmit…to … 把 … 傳到 … ?which changes it into rotary motion 定語從句 II. Text Explanation ? diesel engines ? water pump ? the ignition distributor ? oil pan ? timing gear ? crankshaft and connecting rod mechanism ? valve gear ? fuel system ? exhaust pipe ? exhaust manifold III. Exercises ?Translate the following expressions into Chinese. ?柴油發(fā)動機 ?水泵 ?分電器 ?油底殼 ?正時齒輪 ?曲柄連桿機構(gòu) ?配氣機構(gòu) ?燃油系統(tǒng) ?排氣管 ?排氣歧管 ? 1cylinder head cover ? 2piston ? 3timing toothed belt ? 4water pump ? 5oil pan ? 6oil pump ? 7crankshaft ? 8flywheel ? 9distributor ? 10valve III. Exercises ?The crankshaft represents the final link in the conversion of reciprocating motion at the piston to one of rotation at the flywheel. In the cast of the multicylinder engine, the crankshaft has to control the relative motions of the pistons, while receiving their own impulses. A onepiece construction is most monly used for the motorvehicle crankshaft, which extends the whole length of the engine and must therefore possess considerable rigidity . III. Exercises ?The timingdrive for the engine valve mechanism is taken from the front end of the crankshaft as is the pulley and belt drive for the engine auxiliaries, such as the cooling fan and the alternator for electrical system. attached to the rear end of the crankshaft is the engine flywheel . III. Exercises ?I. Translate the following sentences into Chinese. ?1． Engine is the power source of the automobile. Power is produced by the linear motion of a piston in a cylinder. ?發(fā)動機是汽車的動力源 .它通過汽缸內(nèi)的活塞線性運動產(chǎn)生的 . ?2． The fuel system works according to the requirements of the engine as it provides an airfuel mixture which must be in proportion to the speed and load placed on the engine. ?燃油系統(tǒng)的作用是根據(jù)發(fā)動機的轉(zhuǎn)速和負(fù)荷提供一定比例的可燃混合氣以滿足發(fā)動機的需求。 He is concerned for her safety. 他擔(dān)心她的安全。 II. Text Explanation ?In some application, a narrow groove is cut into the piston above the top ring to serve as a “heat dam” to reduce the amount of heat reaching the top ring. ?groove [gr??v ] n. 凹槽 ?heat dam 隔熱槽 ?譯文： 在有些結(jié)構(gòu)中，為了減少傳到頂部活塞環(huán)的熱量，在活塞環(huán)的上部切割出一個很窄的環(huán)槽，叫做“隔熱槽”?；钊N把活塞和連桿連接起來。 II. Text Explanation ?In order to reduce or eliminate such vibration, it must be provided with counter balanced weights that extend radically from the crankshaft centerline in the opposite direction of the crank arms. ?譯文： 為了減少或消除振動，它必須裝有平衡重，而且平衡重應(yīng)徑向地從曲軸中心線向曲柄相對的方向延伸安裝。 ?The flywheel can carry the clutch, which transmits the drive to the gearbox. III. Exercises ?The main bearings are designed as twopi。遲鈍 。 ?3． Shank of the connecting rod is provided with an Icross section to give the rod maximum rigidity with the minimum of weight. ?為了使連桿得到最大的剛度和最小的重量，連桿桿身部分加工為工形結(jié)構(gòu)。 ?In order to make the aluminum stronger ,a steel liner often placed in the block. ?3．直列式是發(fā)動機中最簡單的一種排列方式。使不安 (+about/for) ?The boy39。 ?②兌換 ?I want to convert some Hong Kong dollars into American dollars. ?我想把一些港元換成美元。 ?If the day turns out wet we may have to change our plans. ?萬一下雨的話，我們也許得改變計劃。 II. Text Explanation ?Convert …..into….. ?They converted the garage into a theater. 他們將車庫改成戲院。 ? The transmission system