汽车发动机外文翻译文献

1、 汽车发动机外文翻译文献汽车发动机外文翻译文献(文档含中英文对照即英文原文和中文翻译)AUTOMOTIVE ENGINE1 Engine Classification and Overall MechanicsThe automobile engines can be classified according to: (1) cycles, (2) coolingsystem, (3) fuel system, (4) ignition method, (5) valve arrangement, (6) cylinderarrangement, (7) engine speed.Engine

2、s used in automobiles are the internal combustion heat engines. Theburning of gasoline inside the engine produces high pressure in the engine combustion 汽车发动机外文翻译文献2 Engine Operating PrinciplesIn four-stroke engine, four strokes of the piston in the cylinder are required to 汽车发动机外文翻译文献Compression st

3、roke4. Exhaust stroke 汽车发动机外文翻译文献At the end of the power stroke the camshaft opens the exhaust valve, and theexhaust stroke begins. Remaining pressure in the cylinder, and upward movement ofthe piston, force the exhaust gases out of the cylinder. At the end of the exhaust stroke,the exhaust valve cl

4、oses and the intake valve opens, repeating the entire cycle ofevents over and over again.Fig. 2-4 V6 engine block 汽车发动机外文翻译文献The cylinder head is attached to the block with high-tensile steel studs. The jointbetween the block and the head must be gas-tight so that none of the burning mixturecan esca

5、pe. This is achieved by using cylinder head gasket. Gaskets are also used toseal joins between the other parts, such as between the oil pan, manifolds, or waterpump and the blocks.3.5 Oil Pan 汽车发动机外文翻译文献 汽车发动机外文翻译文献had four rings, or even five.) The inside surface of the ring fits in the groove on t

6、he piston. The rings outside surface presses against the cylinder walls. Rings provide the needed seal between the piston and the cylinder walls. That is, only the rings contact the cylinder walls. The top two rings are to keep the gases in the cylinder and are calledcompression rings. The lower one

7、 prevents the oil splashed onto the cylinder bore from entering the combustion chamber, and is called an oil ring.4.3 The piston pinThe piston pin holds together the piston and the connecting rod. This pin fits into the piston pin holes and into a hole in the top end of the connecting rod. The top e

8、nd of the rod is much smaller than the end that fits on the crankshaft. This small end fits inside the bottom of the piston. The piston pin fits through one side of the piston, throughthe small end of the rod, and then through the other side of the piston. It holds the rodfirmly in place in the cent

9、er of the piston. Pins are made of high-strength steel and have a hollow center. Many pins are chrome-plated to help them wear better.A piston pinfits into a round hole in the piston. The piston pin joins the piston to the connecting rod. The thick part of the piston that holds the piston pin is the

10、 pin boss.4.4 Connecting RodsThe connecting rod little end is connected to the piston pin. A bush made from asoft metal, such as bronze, is used for this joint. The lower end of the connecting rod fits the crankshaft journal. This is called the big end. For this big-end bearing, steel-backed lead or

11、 tin shell bearings are used. These are the same as those used for the mainbearings. The split of the big end is sometimes at an angle, so that it is small enough to be withdrawn through the cylinder bore. The connecting rod is made from forged alloy steel.4.5 CrankshaftsThe crankshaft is regarded a

12、s the “backbone” of the engine (Fig. 2-7).The crankshaft, in conjunction with the connecting rod, converts the reciprocating motion of the piston to the rotary motion needed to drive the vehicle. It is usually made from car-bon steel which is alloyed with a small proportion of nickel. The main beari

13、ngjournals fit into the cylinder block and the big end journals align with the connectingrods. At the rear end of the crankshaft is attached the flywheel, and at the front end are the driving wheels for the timing gears, fan, cooling water and alternator. The throwof the crankshaft, i.e. the distanc

14、e between the main journal and the big end centers, c 汽车发动机外文翻译文献4.6 FlywheelFig. 2-8 Parts of the valve train 汽车发动机外文翻译文献The valve operating assembly includes the lifters or cam followers, pushrods,rocker arms and shafts or pivot, valve and springs etc. The purpose of this to open andclose the inta

15、ke and exhaust ports that lead to the combustion chambers as required(Fig. 2-8). Valve mechanisms vary depending on the camshaft location. When thecamshaft is positioned in the engine block, valve lifters are mounted in the openingsabove the camshaft. Pushrods are connected from each valve lifter to

16、 a pivoted rockerarm mounted above each valve. A lobe on the camshaft is positioned directly beloweach valve lifter. A typical camshaft drive has a sprocket bolted to the end of thecamshaft, and a matching sprocket is attached to the end of the crankshaft. Those twosprockets may be meshed together o

17、r surrounded a steel chain to have the camshaftdrive. When the lower part of the camshaft lobe is rotating under the valve lifter, thevalve spring holds the valve closed.汽车发动机1 发动机的分类和整体力学汽车发动机可根据如下因素进行分类：（1）循环系统，（2）冷却系统，（3）燃油系统，（4）点火方式，（5）气门布置，（6）气缸排列，（7）发动机转速。用于汽车的发动机是内燃机。汽油在发动机内部燃烧，产生的高压力使活塞移动，这一

18、运动通过连杆传递到曲轴，使它旋转。动力通过动力总成传递到车轮，从而带动汽车前进。发动机需要四个基本系统来运行（图 2-1）。柴油发动机需要其中的三个基本系统来运行。它们是燃油系统、点火系统（柴油除外）、润滑系统和冷却系统。然而，其他三个相关系统也是必要的。这些是排气系统，排放控制系统，启动系统。每个系统执行一项基本工作，使发动机正常运行。 汽车发动机外文翻译文献 汽车发动机外文翻译文献图 2-3 四冲程循环汽油发动机1、进气冲程2、压缩行程3、做功冲程4、排气冲程 汽车发动机外文翻译文献图 2-4 V6 发动机缸体 汽车发动机外文翻译文献图 2-5 缸套3.3 缸盖气缸盖是缸体的顶部，相当于一所房子的屋顶与活塞顶部形成燃烧室。直列式轻型车辆的发动机气缸只有一个缸盖 ;较大的直列式发动机可以有两个或两个以上。正如发动机缸体，缸盖也可由铸铁或铝合金制成。气缸盖携带阀门，气门弹簧，摇臂轴，摇臂，推动气门齿轮工作的推杆。有时，凸轮轴直接安装在缸盖上，不用摇臂控制气门工作。这被称为顶置凸轮轴布置。3.4 垫片缸盖与高强度钢螺栓连接缸体。缸体和头部之间的联合，必须不透气，使燃烧的混合物不能泄漏。这是通过使用气缸盖垫片实现。密封垫片还可以用于连接的其他部分，如油底壳，歧管，或水泵和缸体之间。3.5 油底壳油底壳通常由钢