曲轴毕业设计英文文献及参考书摘要

1、目目 录录 1 1 英文文献翻译英文文献翻译 .1 1.1 the structure of the engine.1 1.2 发动机的结构.9 2 2 专业阅读书目专业阅读书目 .15 2.1 金属切削与机床.15 2.2 数控机床刀具及其应用.15 2.3 数控机床及应用.16 2.4 机床结构件几何优化设计的研究.16 2.5 耐磨损及腐蚀的铸态 28cr白口铸铁.16 2.6 应变疲劳可靠性分析的现状及展望.17 2.7 仿人机器人发展及其技术探索.17 2.8 机械式拖拉机导向探测装置.17 2.9 rgrr- 构造混联 6r 机器人 .17 2.10 大学生机械设计竞赛指导.18

2、1 1 1 英文文献翻译英文文献翻译 1.1 the structure of the engine before you start work, make sure you have a quality onlinemanual from alldata. if you are leaving your engine repair to your mechanic, make sure you read our section on auto warranties on some tips on how to get a good extended warranty to protect y

3、ourself from unexpected repair bills. the engine is the heart of your car, but instead of pumping blood, the engine pumps air and fuel. the engines main function is to convert air and fuel into rotary motion so it can drive the wheels of the car. how does it do that ? pistons:pistons: most common en

4、gines have 4, 6, or 8 pistons which move up and down in the cylinders. on the upper side of the piston is what is called the combustion chamber where the fuel and air mix before ignited. on the other side is the crankcase which is full of oil. pistons have rings which serve to keep the oil out of th

5、e combustion chamber and the fuel and air out of the oil. pistons are made from lightweight aluminum alloy and are designed to float in the cylinder without contacting the cylinder walls. they float on a thin layer of oil which is below the rings. if the rings fail, oil can leak into the combustion

6、chamber and you will see grey smoke coming from the exhaust. if the rings wear or you lose oil to the engine, the pistons can score the cylinder walls damaging the engine and requiring a rebuild. crankshaft:crankshaft: the crankshaft is connected to the pistons via a connecting rod. as the piston mo

7、ves up and down in the cylinder it rotates the crankshaft and converts the straight line motion into rotary 2 motion. valvetrain:valvetrain: the valvetrain consists of valves, rocker arms, pushrods, lifters, and the cam shaft. the valvetrains only job is that of a traffic cop. it lets air and fuel i

8、n and out of the engine at the proper time. the timing is controlled by the camshaft which is synchronized to the crankshaft by a chain or belt. now that we have a general overview of the parts involved lets talk about what happens during the normal operation of your engine. most automotive engine t

9、oday are 4-stroke (or 4-cycle) engines, meaning they have four distinct events which make up the cycle. a 4-stroke engine takes two complete crankshaft revolutions to complete the cycle. below are the 4 complete parts of the 4-stroke cycle. * * intakeintake stroke:stroke: the camshaft opens the inta

10、ke valve and the piston moves down the cylinder. this creates vacuum and sucks in air and fuel into the combustion chamber above the piston. * * compressioncompression stroke:stroke: as the piston starts moving back up the cylinder the intake valve closes and seals off the combustion chamber. the ca

11、uses the air and fuel to compress. * * powerpower stroke:stroke: as the fuel is compressed and the piston nears the top of the cylinder the spark plug fires and ignites the fuel and air. this explosion pushes the piston back down the cylinder and drives the crankshaft. * * exhaustexhaust stroke:stro

12、ke: after the piston reaches the bottom of the cylinder, the exhaust valve opens and the gasses left over from the fuel and air are sent out to the exhaust system. to get a more indepth look into the engine, take a look at the road machines cd free preview. put these four events together in the abov

13、e order and you have a complete cycle. are you asleep yet? thats enough theory, lets talk about the real world and problems you might encounter with the above mentioned parts. 3 pistons:pistons: remember i talked about the rings which seal the combustion chamber from the crankcase. the rings over ti

14、me tend to wear out. when they wear they allow the fuel and air to enter into the oil and dilute it. this dilution reduces the oils ability to lubricate your engine and can cause premature wear. also if the rings wear down they can allow oil from the crankcase to enter the combustion chambers. this

15、will result in oil being burned and exiting your tailpipe as grayish/white smoke. if your car spews grayish white smoke and it does not go stop in the first few minutes after start-up you might have warn rings. if the smoke goes away after start-up look to the valvetrain section. crankshaft:cranksha

16、ft: the crankshaft rides on bearings which can wear down over time. the bearings support the crankshaft and also the rods which connect the pistons to the crankshaft. a loud medium pitched knocking noise in the engine points to warn bearings most of the time. this is usually a costly repair and invo

17、lves removing the crankshaft and either machining the surface where the bearings ride, or replacing the entire crankshaft. to prevent this type of problem, use a high quality oil, change your oil at suggested intervals (3 months or 3000 miles is a safe number) and always maintain your oil level betw

18、een oil changes. many times it is more economical to buy a replacement engine, than to have your engine rebuilt when you have a crankshaft bearing failure. your mechanic can give you a better idea of costs involved. valvetrain:valvetrain: remember the oil smoke problem mentioned above in the piston

19、sections. if your car only smokes grayish/white smoke at start-up you may have leaking valve seals. valve seals keep oil from above the valve from leaking into the combustion chamber. when they wear, they can allow oil to seep into the combustion chamber and collect there until your start the engine

20、 again. you generally do not get oil leaking past the valve seals while the engine is running since the seals expand with the heat of the engine and plug the leak. 4 another common problem is the timing chain or belt will slip or even break causing the camshaft to stop rotating. remember the camshaf

21、t tells the valves when to open and if it stops spinning then the valves stop opening and closing. no valve moving, no engine running . a term you will here when talking about timing chains and belts is interference engine. when an engine is an interference engine the pistons and valves are so close

22、 together that if the valves were to stop moving (broken belt or chain) and the crankshaft kept spinning they would crash into the piston. (thats the interference) this crash tends to do bad things to an engine, breaking valve, bending pushrods, and even cracking pistons. this is why most manufactur

23、ers recommend changing the timing chain or belt every 60,000 miles. timing belts dry out, stretch and deteriorate over time so even if you do not have 60,000 miles on the car think about changing the belt after its 6 years old. if you are wondering if your engine is an interference engine, you can c

24、heck with gates, who makes timing belts and has a pdf file which will tell you if your engine is an interference engine and the recommended service interval. preventivepreventive maintenance:maintenance: * change your oil regularly and use the recommend weight of oil. check your owners manual or und

25、er the hood for the correct oil to be used. * give your engine a chance to warm up before driving if possible. doing this will let the oil get into all parts of the engine before you put a load on the engine. this is even more critical in cooler temperatures when the oil is cold and sluggish. * chan

26、ge your timing belt or chain at your manufacturers recommended interval. * avoid snake oil additives advertised on late night tv. regular oil changes and good maintenance habits will keep your engine running its best. * if you have a turbo-charged engine, give the engine a minute or two to 5 cool do

27、wn before turning it off. this cool down period allows oil to circulate and cool down the bearings in the turbo. if you shut off the engine immediately after hard driving, the oil can gum up around the hot bearings and create problems down the road. whatwhat toto discussdiscuss withwith youryour mec

28、hanic:mechanic: * if you have to replace your engine, discuss the benefits of buying used versus new. if you plan on keeping your car for some time, a new engine might be the best bet. sometimes new engines are not much more expensive than rebuilt ones, and offer the best solution. * when trying to

29、diagnose engine noises, be as descriptive as possible. take note to when the noise occurs, at what throttle position, and when the noise started occurring. sometimes changing the weight of oil being used can cause a new noise to crop up. make sure your mechanic knows if you changed oil brands or wei

30、ght recently. thats about it for the engine. if you have any other questions feel free to e-mail me at automotive electronic control system consists of sensors, the electronic control module, actuators, three major components of the development of new technology can be divided into electronic engine

31、 control technology and electronic technology, vehicle chassis safely electronic-controlled technical. in modern automotive electronic control system in all aspects of each field has made important contribution. based on the chassis of the airbag control technology to automobile technology, for exam

32、ple, the domain to electronic technology as the core of the safety device is studied. the airbag as passive safety car in an important device, effectively protect the life safety of personnel rides. through the statistics and data showed that, in the car collision, can correctly use belt and airbags

33、 can make head injury rate reduce 30-50%, facial injury rate reduce 70-80%. based on the airbag action safety protection and measured the time process were analyzed to verify the 6 rough study the feasibility of the airbag. lathes are machine tools designed primarily to do turning, facing,and boring

34、. very little turning is done on other types of machine tools,and none can do it with equal facility. because lathes also can do drilling and reaming, their versatility permits several operations to be done with a single setup of the workpiece. consequently, more lathes of various types are used in

35、manufacturing than any other machine tool. the essential components of a lathe are the bed, headstock assembly, tailstock assembly, carriage assembly, and the leadscrew and feed rod. the bed is the backbone of a lathe. it usually is made of well-normalized or aged gray or nodular cast iron and provi

36、des a heavy, rigid frame on which all the other basic components are mounted. two sets of parallel, longitudinal ways, inner and outer, are contained on the bed, usually on the upper side. some makers use an inverted v-shape for all four ways, whereas others utilize one inverted v and one fiat way i

37、n one or both sets. they are precision-machined to assure accuracy of alignment. on most modem lathes the ways are surface-hardened to resist wear and abrasion, but precaution should be taken in operating a lathe to assure that the ways are not damaged. any inaccuracy in them usually means that the

38、accuracy of the entire lathe is destroyed. high techs popularization and the application cause the automobile product renewal the step to be getting quicker and quicker, also causes china automobile industry the independent research and development level and the technical level and the disparity int

39、ernationally is getting bigger and bigger, in the concept automobiles development aspect is the difference disparate extremely. joins wto the automobile to sound the alarm to china, simultaneously also brings the infinite opportunity, our government as well as the car company must enlarge to the aut

40、omobile design research and the investment, establishes one kind of positive correct automobile design the 7 idea, widely carries out the concept automobiles design. the headstock is mounted in a fixed position on the inner ways,usually at the left end of the bed. it provides a powered means of rota

41、ting the work at various speeds. essentially, it consists of a hollow spindle, mounted in accurate bearings, and a set of transmission gears-similar to a truck transmission-through which the spindle can be rotated at a number of speeds. most lathes provide from 8 to 18 speeds, usually in a geometric

42、 ratio, and on modem lathes all the speeds can be obtained merely by moving from two to four levers. an increasing trend is to provide a continuously variable speed range through electrical or mechanical drives. because the accuracy of a lathe is greatly dependent on the spindle, it is of heavy cons

43、truction and mounted in heavy beatings, usually preloaded tapered roller or ball types. the spindle has a hole extending through its length, through which long bar stock can be fed. the size d this hole is an important dimension of a lathe because it detemtines the maximum size of bar stock that can

44、 be machined when the material must be fed through spindle. the tailstock assembly consists, essentially, of three parts. a lower casting fits on the inner ways of the bed and can slide longitudinally thereon, with a means for clamping the entire assembly in any desired location. an upper casting fi

45、ts on the lower one and can be movedtransversely upon it, on some type of keyed ways, to permit aligning the tailstock and headstock spindles. the third major component of the assembly is the tailstock quill. this is a hollow steel cylinder, usually about 51 to 76 mm (2 to 3 inches) in diameter, tha

46、t can be moved several inches longitudinally in and out of the upper casting by means of a handwheel and screw. the size of a lathe is designated by two dimensions. the first is known as the swing. this is the maximum diameter of work that can be rotated on a lathe. it is approximately twice the dis

47、tance between the line connecting the 8 lathe centers and the nearest point on the ways. the second size dimension is the maximum distance between centers. the swing thus indicates the maximum workpiece diameter that can be turned in the lathe, while the distance between centers indicates the maximu

48、m length of workpieee that can be mounted between centers. engine lathes are the type most frequently used in manufacturing. llley are heavy-duty machine tools with all the components described previously and have power drive for all tool movements except on the compound rest. they commonly range in

49、 size from 305 to 610 mtn ( 12 to 24 inches) swing and from 610 to 1 219 mm (24 to 48 inches) center distances, but swings up to 1 270 mm (50 inches) and center distances up to 3 658 mm ( 12 feet) are not tmcommon. most have chip pans and a built-in coolant circulating system. smaller engine lathes-

50、with swings usually not over 330 mm ( 13 inches)-also are available in bench type,designed for the bed to be mounted on a bench or cabinet. although engine lathes are versatile and very useful, because of the time required for changing and setting tools and for making measurements on the workpiece,

51、they ale not suitable for quantity production. often the actual chip-production time is less than 30% of the total cycle time. in addition, a skilled machinist is required for all the operations, and such persons are costly and often in short supply. however, much of the operators time is consumed b

52、y simple, repetitious adjustments and in watching chips being made. consequently, to reduce or eliminate the amount of skilled labor that is required, turret lathes, screw machines, and other types of semiautomatic and automatic lathes have been highly developed and are widely used in manufacturing.

53、 the engine lathe, one of the oldest metal removal machines, has a number of useful and highly desirable attributes. today these lathes are used primarily in small shops where smaller quantities rather than large production runs are encountered. 9 the engine lathe has been replaced in todays product

54、ion shops by a wide variety of automatic lathes such as automatic tracer lathes, turret lathes, and automatic screw machines. all the advantages of single-point tooling for maximum metal removal, and the use of form tools for finish and accuracy, are now at the designers fingertips with production s

55、peeds on a par with the fastest processing equipment on the scene today. tolerances for the engine lathe depend primarily on the skill of the operator. the design engineer must be careful in using tolerances of an experimental part that has been produced on the engine lathe by a skilled operator. in

56、 redesigning an experimental part for production, economical tolerances should be used. production machining equipment must be evaluated now, more than ever before, in terms of ability to repeat accurately andrapidly. applying this criterion for establishing the production qualification of a specifi

57、c method, the turret lathe merits a high rating. in designing for low quantities such as 100 or 200 parts, it is most economical to use the turret lathe. in achieving the optimum tolerances possible on the turret lathe, the designer should strive for a minimum of operations. even though pistons and

58、connecting rods tend to become shock absorbers to these loads, radial deflection (both positive and negative) leads to “oscillations” created about the cranks axis of rotation. this will be discussed in more detail later in the story. for now, its important to recognize that crankshafts, as a functi

59、on of torque produced, tend to become “rubber” in the manner by which reciprocating motion (pistons) is converted into rotary motion (torque). as has been previously pointed out, engines are “parts packages” and should be treated as such where no single part operates completely independently. accord

60、ingly, crankshafts can have influence on such variables as valve timing, intake manifold selection and 10 header sizing. but first, we should discuss some of the more common issues. 1.2 发动机的结构 在你开始工作之前，你必须有一个来自 alldata 的高级指南。如果你将发动机交给 机械师修理，务必阅读汽车保证书的相关条款的建议，它如何告诉你获得使你免于意料 之外的维修账单的长期保证。 发动机是汽车的心脏，但它