ImageVerifierCode 换一换
格式:PPT , 页数:45 ,大小:3.80MB ,
文档编号:2993769      下载积分:25 文币
快捷下载
登录下载
邮箱/手机:
温馨提示:
系统将以此处填写的邮箱或者手机号生成账号和密码,方便再次下载。 如填写123,账号和密码都是123。
支付方式: 支付宝    微信支付   
验证码:   换一换

优惠套餐
 

温馨提示:若手机下载失败,请复制以下地址【https://www.163wenku.com/d-2993769.html】到电脑浏览器->登陆(账号密码均为手机号或邮箱;不要扫码登陆)->重新下载(不再收费)。

已注册用户请登录:
账号:
密码:
验证码:   换一换
  忘记密码?
三方登录: 微信登录  
下载须知

1: 试题类文档的标题没说有答案,则无答案;主观题也可能无答案。PPT的音视频可能无法播放。 请谨慎下单,一旦售出,概不退换。
2: 本站所有资源如无特殊说明,都需要本地电脑安装OFFICE2007和PDF阅读器。
3: 本文为用户(三亚风情)主动上传,所有收益归该用户。163文库仅提供信息存储空间,仅对用户上传内容的表现方式做保护处理,对上载内容本身不做任何修改或编辑。 若此文所含内容侵犯了您的版权或隐私,请立即通知163文库(点击联系客服),我们立即给予删除!。
4. 未经权益所有人同意不得将文件中的内容挪作商业或盈利用途。
5. 本站仅提供交流平台,并不能对任何下载内容负责。
6. 下载文件中如有侵权或不适当内容,请与我们联系,我们立即纠正。
7. 本站不保证下载资源的准确性、安全性和完整性, 同时也不承担用户因使用这些下载资源对自己和他人造成任何形式的伤害或损失。

版权提示 | 免责声明

1,本文(汽车专业英语U1-L2(发动机部分)课件.ppt)为本站会员(三亚风情)主动上传,163文库仅提供信息存储空间,仅对用户上传内容的表现方式做保护处理,对上载内容本身不做任何修改或编辑。
2,用户下载本文档,所消耗的文币(积分)将全额增加到上传者的账号。
3, 若此文所含内容侵犯了您的版权或隐私,请立即通知163文库(发送邮件至3464097650@qq.com或直接QQ联系客服),我们立即给予删除!

汽车专业英语U1-L2(发动机部分)课件.ppt

1、陈长梅陈长梅One. Crank-Connecting Rod MechanismCrank-connecting rod mechanism consists of piston-connecting rod group, crankshaft flywheel group, engine block group.1The Engine Block Group(1) The Cylinder BlockThe cylinder block is the basic part of the engine. It forms the main framework or foundation of

2、 the engine. Many parts of the engine are fixed to it. These items include water pump, oil pan, flywheel or clutch housing, ignition distributor, oil pump, fuel pump, and cylinder head.(2) The Cylinder HeadThe cylinder head is bolted to the cylinder block. The top of the cylinder block is covered wi

3、th the cylinder head which contains the combustion chamber (Fig.2-1).Single-cylinder engineSingle-cylinder enginecylinderpistonPiston pinConnecting rodcrankshaftOil pipeInlet valveExhaust valve Timing gearOil pumpconnecting rodflywheelcrankshaftpistoninlet valve进水阀进水阀exhaust valvepush rodTappet挺杆挺杆t

4、iming gears Valve gear阀装置阀装置 Connecting rod Engine BodyCrankcase曲轴箱曲轴箱cylinder blockcylinder headcylinderoil passage and water passage油路和水路油路和水路oil panThe cylinder gasket 气缸垫气缸垫3.cylinder gasket 2.cylinder head1.Cylinder head cover4.Pad 衬垫衬垫5.to fit spark plug安装火花塞安装火花塞I. Pre-questions练练 一一 练练1- cyl

5、inder head cover; 2-cylinder head; 3- cylinder gasket; 4-cylinder block; 5- oil pan油底壳油底壳气缸垫气缸垫气缸体气缸体气缸盖罩气缸盖罩气缸盖气缸盖Components of piston piston toppiston headpiston skirt活塞销孔Piston pin holeSmall end小端小端Connecting rod bushing连杆衬套连杆衬套Connecting rodBig endConnecting rod half shells半壳半壳Connecting rod cap

6、compression ringsoil ringspiston pinpistonconnecting rodcrank bearing half shell曲曲柄轴承半壳柄轴承半壳connecting rod cap III. Exercises2Crankshaft Flywheel Group(1) CrankshaftThe crankshaft is the main rotating shaft of the engine. Designed into the one-piece crankshaft are areas for main bearing journals, cr

7、ankpins, counterweights, flywheel flange, and driving hub. The crankshaft and connecting rod convert the reciprocating motion of the piston to the rotary motion of crankshaft. Crankshafts have drilled oil passages, through which oil can flow from the main bearings to the connecting-rod bearings.(2)

8、FlywheelThe flywheel is a comparatively heavy wheel, bolted to the flywheel flange on the rear end of the crankshaft. The inertia of the flywheel tends to keep it rotating at a constant speed. The flywheel also has several other functions, for example, the flywheel has ring gear in its outer circumf

9、erence,which mesh with teeth located on the starting motor drive pinion in order to crank the engine over. In addition, the rear surface of the flywheel serves as the driving member of the clutch assembly (Fig.2-2).I. Pre-questionsWhats the crankshaft assembly composed of? crankshaftBearing轴承轴承timin

10、g gearflywheelbelt pulley皮带轮皮带轮piston3Piston-Connecting Rod Group(1) The Connecting RodThe connecting rod links the piston to the crankshaft. The small end of connecting rod connects with the piston pin and the big end connects with the crank pin of the crankshaft.(2) The PistonThe engine manufactur

11、er fits a piston into each cylinder of the engine. The piston receives the pressure from the burning air-fuel mixture and converts this pressure into up-and-down reciprocating motion. Because aluminum is half weight less than iron, most of pistons are made from aluminum alloy.(3) Piston RingsThe pis

12、ton ring is a springy split metal ring. It is used to provide the necessary seal to eliminate blowby and to control oil consumption. Engine pistons have two kinds of rings:gas rings and oil rings. The pistonPiston toppiston ringpiston pinconnecting rodTwo. The Valve TrainThe valve train is a series

13、of parts used to open and close the intake and exhaust valves. Meshing the timing gears or installing the timing chains onto the sprockets at a specific place will ensure the valves to open and close at the proper moment in the engines cycle. It consists of camshaft, tappet, pushrod, rocker arm, val

14、ve spring, valve and so on (Fig.2-4).1Camshaft The camshaft is another rotating shaft within the engine, its driven by the engines crankshaft through the timing gears. The camshaft has a series of cams that can change rotary motion to straight-line motion which cause the intake valves and exhaust va

15、lves to open. It rotates at the half speed of the crankshaft. 2Tappet, Pushrods and Rocker ArmsTappet rests on a cam of the camshaft. The pushrod is a metal rod that fits between the tappet and the rocker arm. Its function is to transmit cam lobe lift to the rocker arm assembly. The rocker arm is no

16、thing more than a lever. Its function is to convert the up wardmotion of a pushrod into downward motion that compresses the spring and opens the valve.3Valves and Valve SpringsModern engines have cylinder heads that contain valves. Each cylinder requires at least two valves:an intake valve and an ex

17、haust valve. The valves are compressed and closed by valve springs. As the valve is opened by the camshaft, it compresses the valve spring.valves rocks push rods tappets camshaft Words Phrases(单词和短语)(单词和短语)I. Pre-questions What is regarded as the “backbone” of the engine and why? Crankshaft, because

18、 it can change the reciprocating motion (往复运往复运动动)of the piston into rotary(旋转旋转) motion and handle(处理处理) the entire(全部全部) power output. Regard as- 译为:被叫做-I. Pre-questions Whats the function of the flywheel? helping the engine to run smoothly(平稳平稳) during the power stroke and releasing(释放释放) it duri

19、ng the other strokes; carrying the clutch, which transmits(传输传输) the drive to the gearbox; has the starter ring gear ,around its. 功功 能能I. Pre-questions Where is the flywheel in the engine? the rear of the crankshaft. the starter ring gear起动环形齿轮起动环形齿轮I. Pre-questions What is the function of the valve

20、 gear in an internal combustion engine? Open the inlet valve in time and let the air-fuel mixture into the cylinders in inlet stroke. Open the exhaust valve in time and let the exhaust gases out of the cylinder in exhaust stroke. I. Pre-questions What does the valve gear of an internal combustion en

21、gine consist of?rocks push rods tappets camshaft spring valves I. Pre-questions Which component drives the camshaft? crankshafttension gearcrankshaft timing gearcamshaft timing gearTiming gear-belt I. I.Pre-questionsPre-questions What is the function of the valve spring? The valve spring provides (提

22、供提供) the force (力量力量) necessary (必要的必要的) to close the valve and hold (控制控制) it tightly (紧紧紧紧地地) against (依附着依附着) its seat (底座底座).camshaftcamshaftpistonspringPiston pinvalveConnecting rodII. Text ExplanationIn an internal combustion engine, the valve gear provides timely admission of the air-fuel mix

23、ture into the cylinders and exhaust of the gases from them.internal combustion engine:internal combustion engine:内燃机内燃机admission- intoadmission- into:将:将-吸入吸入-里里译文:译文:在内燃机中,配气机构能定时地将新鲜的混在内燃机中,配气机构能定时地将新鲜的混合气充入气缸,并且将废气从气缸中排出。合气充入气缸,并且将废气从气缸中排出。II. Text Explanation internal combustion engine 内燃机内燃机 va

24、lve gear 配气机构配气机构 timely 及时的,适时的及时的,适时的 fresh charge 新鲜混合气新鲜混合气 air- fuel mixture 燃油混合气燃油混合气II. Text Explanation The valve gear is composed of timing gears, camshaft, tappets, push rods, rocks, valves, valve seats, spring with fasteners and valve guides. be composed of 由由组成组成 tappet 挺杆挺杆 fastener 紧固

25、件紧固件 valve guide 气门导管气门导管 Valve Function (作用作用) Open a passage, when moving in one direction(方向方向), and to close it when moving in the oppositepzit (相反的;) direction. valve headstem III. Exercises 1-rocks 2-valve spring 3-valve guide 4-valve 5-valve seat 6-camshaft 7-tappet 8-push rod翻翻 译:译: 1、 Most

26、engines had two valves for each cylinder, one is for the inlet and the other for the exhaust . 译:许多发动机的每个气缸都有两个译:许多发动机的每个气缸都有两个气气 门门,一个是,一个是进气门进气门、一个是、一个是排气门排气门。 4、The valves are located within the cylinder head on most engines designed today. are located within 被安装在被安装在-里面;里面; designed adj. 有规则的,规矩的;有规则的,规矩的; 译:气门被有规则的安装在汽缸头部里面。译:气门被有规则的安装在汽缸头部里面。PracticePractice:P15. E x :1-2P15. E x :1-2

侵权处理QQ:3464097650--上传资料QQ:3464097650

【声明】本站为“文档C2C交易模式”,即用户上传的文档直接卖给(下载)用户,本站只是网络空间服务平台,本站所有原创文档下载所得归上传人所有,如您发现上传作品侵犯了您的版权,请立刻联系我们并提供证据,我们将在3个工作日内予以改正。


163文库-Www.163Wenku.Com |网站地图|