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变速器介绍外文文献翻译、中英文翻译、外文翻译

变速器介绍外文文献翻译、中英文翻译、外文翻译

附录附录A 英文文献Transmission descriptionTransmission gearbox's function the engine's output rotational speed is high, the maximum work rate and the maximum torque appears in certain rotational speed area. In order to display engine's optimum performance, must have a set of variable speed gear, is coordinated the engine the rotational speed and wheel's actual moving velocity. The transmission gearbox may in the automobile travel process, has the different gear ratio between the engine and the wheel, through shifts gears may cause the engine work under its best power performance condition. Transmission gearbox's trend of development is more and more complex, the automaticity is also getting higher and higher, the automatic transmission will be future mainstream.Automotive Transmission's mission is to transfer power, and in the process of dynamic change in the transmission gear ratio in order to adjust or change the characteristics of the engine, at the same time through the transmission to adapt to different driving requirements. This shows that the transmission lines in the automotive transmission plays a crucial role. With the rapid development of science and technology, people's car is getting higher and higher performance requirements, vehicle performance, life, energy consumption, such as vibration and noise transmission depends largely on the performance, it is necessary to attach importance to the study of transmission.Transmission gearbox's pattern the automobile automatic transmission common to have three patterns: Respectively is hydraulic automatic transmission gearbox (AT), machinery stepless automatic transmission (CVT), electrically controlled machinery automatic transmission (AMT). At present what applies is most widespread is, AT becomes automatic transmission's pronoun nearly.AT is by the fluid strength torque converter, the planet gear and the hydraulic control system is composed, combines the way through the fluid strength transmission and the gear to realize the speed change bending moment. And the fluid strength torque converter is the most important part, it by components and so on pump pulley, turbine wheel and guide pulley is composed, has at the same time the transmission torque and the meeting and parting function.And AT compare, CVT has omitted complex and the unwieldy gear combination variable transmission, but is two groups of band pulleys carries on the variable transmission. Through changes the driving gear and the driven wheel transmission belt's contact radius carries on the speed change. Because has cancelled the gear drive, therefore its velocity ratio may change at will, the speed change is smoother, has not shifted gears kicks the feeling.AMT and the hydraulic automatic transmission gearbox (AT) is the having steps automatic transmission equally. It in the ordinary manual transmission gearbox's foundation, through installs the electrically operated installment which the microcomputer controls, the substitution originally coupling's separation which, the joint and the transmission gearbox completes by the manual control elects to keep off, to shift gears the movement, realizes fluid drive.Manual transmission gear mainly uses the principle of deceleration. Transmission within the group have different transmission ratio gear pair, and the car at the time of shift work, that is, through the manipulation of institutions so that the different transmission gear pair work. Manual transmission, also known as manual gear transmission, with axial sliding in the gears, the meshing gears through different speed to achieve the purpose of torque variation. Manual shift transmission can operate in full compliance with the will of the driver, and the simple structure, the failure rate is relatively low, value for money.Automatic transmission is based on speed and load (throttle pedal travel) fortwo-parameter control gear in accordance with the above two parameters to automatically take-off and landing. Automatic transmission and manual transmission in common, that is, there are two-stage transmission, automatic transmission can only speed the pace to automatically shift, manual transmission can be eliminated, "setback" of the shift feel.Automatic transmission is a torque converter, planetary gears and hydraulic manipulation of bodies, through the hydraulic transmission and gear combination to achieve the purpose of variable-speed torque variation.Also known as CVT-type continuously variable CVT. This transmission and automatic transmission gear generally the biggest difference is that it eliminates the need of complex and cumbersome combination of variable-speed gear transmission, and only two groups to carry out variable-speed drive pulley.CVT transmission than the traditional structure of simple, smaller and it is not the number of manual gear transmission, no automatic transmission planetary gear complex group, mainly rely on the driving wheel, the driven wheel and the transmission ratio brought about by the realization of non-class change.Widely used in automotive internal combustion engine as a power source, the torque and speed range is very small, and complex conditions require the use of motor vehicles and the speed of the driving force in the considerable changes in the scope. To resolve this contradiction, in the transmission system to set up the transmission to change transmission ratio, the expansion of the driving wheel torque and speed range in order to adapt to constantly changing traffic conditions, such as start, acceleration, climbing and so on, while the engine in the most favorable conditions to work under the scope; in the same direction of rotation of the engine under the premise of the automobile can be driven back; the use of neutral, interruption of power transmission, in order to be able to start the engine, idle speed, and ease of transmission or power shift . Transmission is designed to meet the above requirements, so that the conditions in a particular vehicle stability.In addition to transmission can be used to meet certain requirements, but also to ensure that it and the car can have a good match, and can improve the car's power andeconomy to ensure that the engine in a favorable condition to increase the scope of the work of the use of motor vehicles life, reduce energy consumption, reduce noise, such as the use of motor vehicles.Today the world's major car companies CVT are very active in the study. The near future, with electronic control technology to further improve, electronically controlled Continuously Variable Transmission-type is expected to be a wide range of development and application.附录B 文献翻译变速器介绍发动机的输出转速非常高,最大功率及最大扭矩在一定的转速区出现。

变速器设计,中英文带翻译

变速器设计,中英文带翻译

原文:Transmission designAs we all know automobile engine to a certain speed can be achieved under the best conditions, when compared issued by the power, fuel economy is relatively good. Therefore, we hope that the engine is always in the best of conditions to work under. However, the use of motor vehicles need to have different speeds, thus creating a conflict. Transmission through this conflict to resolve.Automotive Transmission role sum up in one sentence, called variable speed twisting, twisting or slow down the growth rate by increasing torsional. Why can slow down by twisting, and the growth rate but also by twisting? For the same engine power output, power can be expressed as N = WT, where w is the angular velocity of rotation. When N fixed, w and T is inversely proportional to the. Therefore, the growth rate will reduce twisting, twisting slowdown will increase. Automotive Transmission speed gear based on the principle of variable twisted into various stalls of different transmission ratio corresponding to adapt to different operational conditions.General to set up a manual gearbox input shaft, intermediate shaft and output shaft, also known as the three-axis, as well as Daodang axis. Three-axis is the main transmission structure, input shaft speed is the speed of the engine, the output shaft speed is the intermediate shaft and output shaft gear meshing between different from the speed. Different gears are different transmission ratio, and will have a different speed. For example Zhengzhou richan ZN6481W2G manual transmission car-SUV, its transmission ratio are: 1 File 3.704:1; stalls 2.202:1; stalls 1.414:1; stalls 1:1 5 stalls (speeding file) 0.802: 1.When drivers choose a launch vehicle stalls, Plectrum will be 1 / 2 file synchronization engagement with a back stall gear and output shaft lock it, the power input shaft, intermediate shaft and output shaft gear of a stall, a stall the output shaft gear driven, and the output shaft power will be transmitted to the drive shaft (red arrow). A typical stall Biansuchilun transmission ratio is 3:1, that is to say three lapsto the input shaft and output shaft to a circle.When the growth rate of car drivers choose two stalls, Plectrum will be 1 / 2-file synchronization and file a joint separation after 2 stall and lock the output shaft gear, power transmission line similar, the difference is that the output shaft gear of a stall 2 stall replaced by the output shaft gear driven. 2 stall Biansuchilun typical transmission ratio is 2.2:1, 2.2 laps to the input shaft and output shaft to a circle than a stall speed increase, lower torque.When refueling vehicle drivers growth stalls option 3, Plectrum to 1 / 2 back to the free file-synchronization position, and also allows the 3 / 4 file synchronization Mobile stall until 3 in the output shaft gear lock, power can be into the shaft axis - intermediate shaft - the output shaft of the three stalls Biansuchilun, led through three stalls Biansuchilun output shaft. 3 stalls typical transmission ratio is 1.7:1, 1.7 laps to the input shaft and output shaft to a circle is further growth.When car drivers Option 4 refueling growth stalls, Plectrum will be 3 / 4 from the 3-file synchronization stall gear directly with the input shaft gear joint initiative, and power transmission directly from the input shaft to the output shaft, the transmission ratio at 1:1, that the input shaft and output shaft speed the same. The driving force without intermediate shaft, also known as direct file, the file transmission than the maximum transmission efficiency. Most cars run-time files are used directly to achieve the best fuel economy.Shift into the first interval when, in a free transmission when Biansuchilun output shaft is not locked in, they cannot rotate the output shaft driven, not power output.General automotive manual transmission than the main 1-4 stalls, usually the first designers to determine the minimum (one stall) and maximum (4 files) transmission ratio, the middle stall drive by geometric progression than the general distribution. In addition, there are stalls Daodang and speeding, speeding file is also known as the five stalls.When the car to accelerate to more than car drivers with the choice of five stalls, and a typical five-transmission ratio is 0.87:1, which is driven by a pinion gear, thegear when the initiative to 0.87 zone, passive gear have been transferred to a circle of the End.Dao Dang, the opposite direction to the output shaft rotation. If one pair of meshing gears when we reverse rotation, with a middle gear, it will become the same to the rotation. Use of this principle, we should add a gear Daodang the "media" will be rotational direction reversed, it will have a Daodang axis. Daodang installed in the transmission shaft independent crust, and the intermediate shaft parallel axis gear with the intermediate shaft and output shaft gear meshing gears, will be contrary to the output shaft.Daodang usually used for the synchronization control also joins five stalls, stalls and Daodang 5 position in the same side. As a middle gear, the general transmission Daodang transmission ratio greater than 1 file transmission ratio, by twisting, steep slope with some vehicles encountered on the progress stalls falters with a Daodang boost.Ride from the driver of the considerations, better transmission stall, stall adjacent stall more than the transmission changes the ratio of small, and easy to shift smoothly. However, the short comings of the stalls is more transmission structure is complicated, bulky, light vehicle transmission is generally 4-5 stalls. At the same time, transmission ratio is not integral, but with all of the decimal point, it is because of the gear teeth meshing is not caused by the whole multiples of two gear teeth can lead to the whole multiples of two meshing gears of uneven wear, making the tooth surface quality have a greater difference.Manual transmission and synchronizerManual transmission is the most common transmission, or MT. Its basic structure sum up in one sentence, is a two-axle shaft, where input shaft, the shaft axis and intermediate shaft, which constitute the main body of the transmission and, of course, a Daodang axis. Manual transmission known as manual gear transmission, which can be in the axial sliding gears, the gears meshing different variable speed reached twisting purpose. Typical manual transmission structure and principles are as follows.Input shaft also said that the first axis, and its front-end spline driven directlywith the clutch disc sets with the spline , by the transfer of torque from the engine. The first axis of the intermediate shaft and gears meshing gears often, as long as the shaft axis to a turn, the intermediate shaft and gear also will be rotating. Vice also said intermediate shaft axis, the axis-even more than the size gear. Also known as the second output shaft axis, the axis of various sets of gear stall progress can be manipulated at any time in the role of the device and the corresponding intermediate shaft gear meshing, thus changing its speed and torque. With the end of the output shaft spline associated with the drive shaft through the drive shaft torque transmitted to the drive axle reducer.Thus, progress stalls drive transmission path is: input shaft gear often rodents - often rodents intermediate shaft gear - corresponding intermediate shaft gear - the second axis corresponding gear. Reversing the gear shaft can be manipulated by the device pick in the axis movement, and the intermediate shaft and output shaft gear meshing gears, to the contrary to the direction of rotation output.Most cars have five stalls and a Daodang forward, a certain degree of each stall transmission ratio, the majority of stalls transmission ratio greater than 1, 4 file transmission ratio of 1, known as direct stalls, and transmission ratio is less than 1 No.5 stall called accelerated stall. Free at the output shaft gear in a position of non-engagement, unacceptable power transmission.The transmission input shaft and output shaft rotational speed to their own, transform a stall when there is a "synchronous". Two different rotational speed gear meshing force will impact the collision occurred, damage gear. Therefore, the old transmission shift to a "feet-off" approach, or stall on the location of the free stay for a while by stalls in the free position refueling doors, in order to reduce the speed differential gear. However, this operation is relatively more complicated and difficult to grasp accurate. So designers create a "synchronized," and allows synchronization through the meshing of gears to be consistent speed and smooth meshing.At present Synchronous Transmission is based on the synchronization of inertia, mainly from joint sets, synchronous lock ring, and so on, it is characterized by friction on the role of synchronization. Splice sets Genlock engagement ring gear and the ringgear when it had Chamfer (Lock angle), Genlock within the cone ring gear engagement with the question of cone ring gear contact friction. Lock and cone angle has been made in the design of an appropriate choice to be made friction cone of the teeth meshing with the ring gear quickly sets pace at the same time will have a Lock role and to prevent the gears meshing in sync before. When synchronization lock cone ring gear engagement with the question of cone ring gear after contact in the effects of friction torque gear speed quickly lower (or higher) with the same speed synchronous lock ring, the two synchronous rotation of the gear Genlock Central zero speed, thus moment of inertia also disappear, then in force under the impetus of engagement sets unhindered and synchronization lock ring gear engagement, and further engagement with the question of gear engagement and the completion Gear Shift Process.The automatic gearboxThe automatic gearbox chooses to block the pole the equal to moving the stick shift of the gearbox, having generally below several blocks:P( parking), R( pour to block), N( get empty to block), D( go forward), S( or2, namely for 2 block soon), L.( or1, namely for 1 block soon)This several an usage for blocking a right usages coming driver the automatic gearbox is automotive of person to say particularly important, underneath let us very much familiar with once automatic gearbox eachly blockings main theme.The usage of the P ( the parking blocks)The launches the luck turns as long as choose to block the pole in driving the position, automatic gearbox car run about very easily.But park, choose to block the pole must pull into of P, from but pass the internal parking system in gearbox moves the device will output the stalk lock lives, combining to tense the hand system move, preventing the car ambulation.The usage of the R( pour to block)R a control for is pouring blocking, using inside wanting slicing recording, automatic gearbox car unlike moving gearbox car so can using half moving, so while reversing the car wanting special attention accelerating pedal.The usage of the N( get empty to block)The N is equal to get empty to block, can while starting or hour of trailer usage.At wait for the signal or block up the car will often often choose to block the pole keeps in the of D, trampling at the same time the next system move.If time is very short, do like this is an admission of, but if stop the time long time had better change into of N, combine to tense the hand system moves.Because choose to block the pole in driving the position, the automatic gearbox car has generally and all to drive the trend faintly, long hours trample the system move same as a deterrent this kind of trend, make gearbox oil gone up, the oil liquid changes in character easily.Particularly in the air condition machine work, launch the soon higher circumstance in machine bottom more disadvantageous.Some pilots for the sake of stanza oil, at made good time or go down slope will choose to block the pole pull the of N skids, this burn the bad gearbox very easily, launching the machine to revolves soon in the however because the gearbox outputs at this time the stalk turns soon very high,, the oil pump provides the oil shortage, lubricating the condition worsen, burn the bad gearbox easily.The usage of the D( go forward to block)Will choose to block when is normal to drive the pole put in the of D, car can at 1 ~4 block( or 3 block) its change to block automatically.The of D drives the position most in common usely. What demand control is: Because the automatic gearbox is soon high and low with car to come to make sure to block according to the accelerator size a, so accelerate the pedal operation method is different, changing to block the hour of the car is soon too not same alike.If start hour quick accelerate the pedal tramples the bottom, rising to block the night, accelerating the ability is strong, arriving certain car soon behind, then will accelerate the pedal loosen to open very quickly, car can rise to block immediately, launch like this the machine voice is small, comfortable good.The another characteristics of the D is a compulsory low blocking, easy to high speed the hour overtakes a car, will accelerate quickly in of D drove the pedal trample after all, connect the compulsory low fend off the pass and then can reduce to block automatically, the car accelerates very quickly, after overtaking a car loosen to openthe pedal of acceleration to can rise to block automatically again.The usage of the S, of L low the usage that blockThe automatic gearbox in in is placed in the low blocking the scope on of S or of Ls, can usage under an etc. circumstance.It change to can make use of to launch well into of S or of Ls the mechanism move, avoiding the car wheel system move the machine over hot, cause the system move the effect descent while going down slope.But change into from the of D of S or of L, car soon can't higher than rise to block the car homologously soon, otherwise strong vibration in opportunity to launch, make gearbox oil hoicked, even will damage the gearbox.The is another at rain fog weather hour, if the road adheres to the term bad, can change into a position for or of L, fixing at somely first lowly blocking driving, doing not use can automatically changing blocking, in order to prevent the car beats slippery.Must keep firmly in mind at the same time, beat the slippery hour can will choose to block the pole pushes into a motive for, cutting off launching machine, toing guarantee a car the safety.汽车变速器设计----------英文文献翻译我们知道,汽车发动机在一定的转速下能够达到最好的状态,此时发出的功率比较大,燃油经济性也比较好。

变速器外文翻译

变速器外文翻译

Continuously Variable Transmissions An Overview of CVT Research Past, Present, and FutureKevin R. Lang21W. 732May 3, 2000Table of Contents Introduction (1)CVT Theory & Design (2)Push Belt (2)Toroidal Traction Drive (2)Variable Diameter Elastomer Belt (3)Other CVT Varieties (3)Background & History (3)Inherent Advantages & Benefits (4)Challenges & Limitations (5)Research & Development (6)New CVT Research (7)Future Prospects for CVTs (9)CVTs & Hybrid Electric Vehicles (9)Conclusion (10)Works Cited (11)Figures and TablesFigure 1 – Metal Push Belt CVT (2)Figure 2 – Toroidal CVT (2)Figure 3 – Variable Diameter Belt CVT (3)Figure 4 – GM’s New CVT Design (6)Figure 5 – Audi CVT with link chain (6)Figure 6 – Cutaway of Audi CVT (7)Table 1 – Efficiency vs. Gear Ratio for Automatic Transmission (4)Table 2 – Efficiency of Various CVT Designs (4)AbstractAs the U.S. government enacts new regulations for automotive fuel economy and emissions, the continuously variable transmission, or CVT, continues to emerge as a key technology for improving the fuel efficiency of automobiles with internal combustion (IC) engines. CVTs use infinitely adjustable drive ratios instead of discrete gears to attain optimal engine performance. Since the engine always runs at the most efficient number of revolutions per minute for a given vehicle speed, CVT-equipped vehicles attain better gas mileage and acceleration than cars with traditional transmissions.CVTs are not new to the automotive world, but their torque capabilities and reliability have been limited in the past. New developments in gear reduction and manufacturing have led to ever-more-robust CVTs, which in turn allows them to be used in more diverse automotive applications. CVTs are also being developed in conjunction with hybrid electric vehicles. As CVT development continues, costs will be reduced further and performance will continue to increase, which in turn makes further development and application of CVT technology desirable.This paper evaluates the current state of CVTs and upcoming research and development, set in the context of past development and problems traditionally associated with CVTs. The underlying theories and mechanisms are also discussed.IntroductionAfter more than a century of research and development, the internal combustion (IC) engine is nearing both perfection and obsolescence: engineers continue to explore the outer limits of IC efficiency and performance, but advancements in fuel economy and emissions have effectively stalled. While many IC vehicles meet Low Emissions Vehicle standards, these will give way to new, stricter government regulations in the very near future. With limited room for improvement, automobile manufacturers have begun full-scale development of alternative power vehicles. Still, manufacturers are loath to scrap a century of development and billions or possibly even trillions of dollars in IC infrastructure, especially for technologies with no history of commercial success. Thus, the ideal interim solution is to further optimize the overall efficiency of IC vehicles.One potential solution to this fuel economy dilemma is the continuously variable transmission (CVT), an old idea that has only recently become a bastion of hope to automakers. CVTs could potentially allow IC vehicles to meet the first wave of new fuel regulations while development of hybrid electric and fuel cell vehicles continues. Rather than selecting one of four or five gears, a CVT constantly changes its gear ratio to optimize engine efficiency with a perfectly smooth torque-speed curve. This improves both gas mileage and acceleration compared to traditional transmissions.The fundamental theory behind CVTs has undeniable potential, but lax fuel regulations and booming sales in recent years have given manufacturers a sense of complacency: if consumers are buying millions of cars with conventional transmissions, why spend billions to develop and manufacture CVTs? Although CVTs have been used in automobiles for decades, limited torque capabilities and questionable reliability have inhibited their growth. Today, however, ongoing CVT research has led to ever-more-robust transmissions, and thus ever-more-diverse automotive applications. As CVT development continues, manufacturing costs will be further reduced and performance will continue to increase, which will in turn increase the demand for further development. This cycle of improvement will ultimately give CVTs a solid foundation in the world’s automotive infrastructure.Figure (1) – Metal Push Belt CVTFrom [3]Figure (2) – Toroidal CVTFrom [3]CVT Theory & DesignToday’s automobiles almost exclusively use either a conventional manual or automatictransmission with “multiple planetary gear sets that use integral clutches and bands to achieve discrete gear ratios” [3]. A typical automatic uses four or five such gears, while a manual normally employs five or six. The continuously variable transmission replaces discrete gear ratios with infinitely adjustable gearing through one of several basic CVT designs.Push BeltThis most common type of CVT usessegmented steel blocks stacked on a steel ribbon, asshown in Figure (1). This belt transmits powerbetween two conical pulleys, or sheaves, one fixedand one movable [3]. With a belt drive:In essence, a sensor reads the engine output and then electronically increases or decreases thedistance between pulleys, and thus the tension of the drive belt. The continuously changing distance between the pulleys—their ratio to one another—is analogous to shifting gears. [6]Push-belt CVTs were first developed decades ago, but new advances in belt design have recently drawn the attention of automakers worldwide.Toroidal Traction-DriveThese transmissions use the high shear strength of viscousfluids to transmit torque between an input torus and an outputtorus. As the movable torus slides linearly, the angle of a rollerchanges relative to shaft position, as seen in Figure (2). Thisresults in a change in gear ratio [3].Variable Diameter Elastomer BeltThis type of CVT, as represented in Figure (2), usesa flat, flexible belt mounted on movable supports. Thesesupports can change radius and thus gear ratio. However,the supports separate at high gear ratios to form adiscontinuous gear path, as seen in Figure (3). This can lead to the problems with creep and slip that have plagued CVTs for years [3]. This inherent flaw has directed research and development toward push belt CVTs.Other CVT VarietiesSeveral other types of CVTs have been developed over the course of automotive history, butthese have become less prominent than push belt and toroidal CVTs. A nutating traction drive uses a pivoting, conical shaft to change “gears” in a CVT. As the cones change angle, the inlet radius decreases while the outlet radius increases, or vice versa, resulting in an infinitely variable gear ratio [3]. A variable geometry CVT uses adjustable planetary gearsets to change gear ratios, but this is more akin to a flexible traditional transmission than a conventional CVT.Background & HistoryTo say that the continuously variable transmission (CVT) is nothing new would be a grossunderstatement: Leonardo da Vinci sketched his idea for a CVT in 1490 [1]. In automotive applications,CVTs have been around nearly as long as cars themselves, and certainly as long as conventionalautomatics. General Motors actually developed a fully toroidal CVT in the early 1930s and conducted extensive testing before eventually deciding to implement a conventional, stepped-gear automatic due to cost concerns. General Motors Research worked on CVTs again in the 1960s, but none ever sawproduction [2]. British manufacturer Austin used a CVT for several years in one of its smaller cars, but “it was dropped due to its high cost, poor reliability, and inadequate torque transmission” [2]. Many early CVTs used a simple rubber band and cone system, like the one developed by Dutch firm Daf in 1958 [1].Figure (3) – Variable Diameter Belt CVTFrom [3]However, the Daf CVT could only handle a 0.6 L engine, and problems with noise and rough starts hurt its reputation [1]. Uninspired by these early failures, automakers have largely avoided CVTs until very recently, especially in the United States.Inherent Advantages & BenefitsCertainly, the clunk of a shifting transmission is familiar to all drivers. By contrast, a continuously variable transmission is perfectly smooth—it naturally changes “gears” discreetly and minutely such that the driver or passenger feels only steady acceleration. In theory, a CVT would cause less engine fatigue and would be a more reliable transmission, as the harshness of shifts and discrete gears force the engine to run at a less-than-optimal speed.Moreover, CVTs offer improved efficiency and performance. Table (1) below shows the power transmission efficiency of a typical five-speed automatic, i.e. the percentage of engine power translated through the transmission. This yields an average efficiency of 86%, compared to a typical manual transmission with 97% efficiency [3]. By comparison, Table (2) below gives efficiency ranges for several CVT designs.Table (1) Efficiency vs. Gear Ratio for Automatic Transmission [3] Gear Efficiency Range160-85%260-90%385-95%490-95%585-94%Table (2) Efficiency of Various CVT Designs [3] CVT Mechanism Efficiency Range Rubber Belts90-95%Steel Belts90-97%Toroidal Traction70-94%Nutating Traction75-96%Variable Geometry85-93%These CVTs each offer improved efficiency over conventional automatic transmissions, and their efficiency depends less on driving habit than manual transmissions [3]. Moreover:Because the CVT allows an engine to run at this most efficient point virtuallyindependent of vehicle speed, a CVT equipped vehicle yields fuel economy benefitswhen compared to a conventional transmission (3)Testing by ZF Getriebe GmbH several years ago found that “the CVT uses at least 10% less fuel than a 4-speed automatic transmission” for U.S. Environmental Protection Agency city and highway cycles. Moreover, the CVT was more than one second faster in 0-60 mph acceleration tests [5]. The potential for fuel efficiency gains can also be seen in the CVT currently used in Honda’s Civic. A Civic with atraditional automatic averages 28/35 miles per gallon (mpg) city/highway, while the same car with a CVT gets 34/38 mpg city/highway [4]. Honda has used continuously variable transmissions in the Civic for several years, but these are 1.6 liter cars with limited torque capabilities. Ongoing research and development will inevitably expand the applicability of CVTs to a much broader range of engines and automobiles.Challenges & LimitationsCVT development has progressed slowly for a variety of reasons, but much of the delay in development can be attributed to a lack of demand: conventional manual and automatic transmissions have long offered sufficient performance and fuel economy. Thus, problems encountered in CVT development usually stopped said progress. “Designers have … unsuccessfully tried to develop [a CVT] that can match the torque capacity, efficiency, size, weight, and manufacturing cost of step-ratio transmissions” [6].One of the major complaints with previous CVTs has been slippage in the drive belt or rollers. This is caused by the lack of discrete gear teeth, which form a rigid mechanical connection between to gears; friction drives are inherently prone to slip, especially at high torque. With early CVTs of the 1950s and 1960s, engines equipped with CVTs would run at excessively high RPM trying to “catch up” to the slipping belt. This would occur any time the vehicle was accelerated from a stop at peak torque:“For compressive belts, in the process of transmitting torque, micro slip occurs betweenthe elements and the pulleys. This micro slip tends to increase sharply once thetransmitted torque exceeds a certain value …” [8]For many years, the simple solution to this problem has been to use CVTs only in cars with relativelylow-torque engines. Another solution is to employ a torque converter (such as those used in conventional automatics), but this reduces the CVT’s efficiency [2].Perhaps more than anything else, CVT development has been hindered by cost. Low volume and a lack of infrastructure have driven up manufacturing costs, which inevitably yield higher transmission prices. With increased development, most of these problems can be addressed simply by improvements in manufacturing techniques and materials processing. For example, Nissan’s Extroid “is derived from aFigure (4) – GM’s New CVT designFrom [6]Figure (5) – Audi CVT with link chainFrom [1]century-old concept, perfected by modern technology, metallurgy, chemistry, electronics, engineering,and precision manufacturing” [2].In addition, CVT control must be addressed. Even if a CVT can operate at the optimal gear ratio at any speed, how does it “know” what ratio to select? Manual transmissions have manual controls,where the driver shifts when he or she so desires; automatic transmissions have relatively simple shifting algorithms to accommodate between three and five gears. However, CVTs require far more complex algorithms to accommodate an infinite division of speeds and gear ratios.Research & DevelopmentWhile IC development has slowed in recent years asautomobile manufacturers devote more resources to hybrid electricvehicles (HEVs) and fuel cell vehicles (FEVs), CVT research anddevelopment is expanding quickly. Even U.S. automakers, who havelagged in CVT research until recently, are unveiling new designs:General Motors plans to implement metal-belt CVTs in some vehiclesby 2002 [6].The Japanese and Germans continue to lead the way in CVT development. Nissan has taken a dramatic step with its “Extroid” CVT, offered in the home-market Cedric and Gloria luxury sedans. This toroidal CVT costs more than a conventional belt-driven CVT, but Nissan expects the extra cost to be absorbed by the luxury cars’ prices [2]. The Extroid uses a high viscosity fluid to transmit power between the disks and rollers, rather than metal-to-metal contact. Coupled with a torque converter, this yields“exceptionally fast ratio changes”. Most importantly, though, theExtroid is available with a turbocharged version of Nissan’s 3.0 literV6 producing 285 lb-ft of torque; this is a new record for CVTtorque capacity [2].Audi’s new CVT offers both better fuel mileage than a conventional automatic and better acceleration than even aFigure (6) – Cutaway of Audi CVT From [1]manual transmission. Moreover, Audi claims it can offer the CVT at only a slight price increase [1]. This so-called “multitronic” CVT uses an all-steel link plate chain instead of a V-belt in order to handle up to 280 lb-ft of torque [1]. In addition, “Audi claims that the multitronic A6accelerates from 0-100 km/h (0-62 mph) 1.3 s quicker than a gearedautomatic transmission and is 0.1 s quicker over the same speed than anequivalent model with “optimum” use of a five speed manual gearbox”[1]. If costs were sufficiently reduced, a transmission such as this couldbe used in almost any automobile in the world.Many small cars have used CVTs in recent years, and many more will use them in the near future. Nissan, Honda, and Subaru currently use belt-drive CVTsdeveloped with Dutch company Van Doorne Transmissie (VDT) in some of their smaller cars [7]. Suzuki and Daihatsu are jointly developing CVTs with Japanese company Aichi Machine, using analuminum/plastic composite belt reinforced with Aramid fibers. Their CVT uses an auxiliary transmission for starts to avoid low-speed slip. After about 6 mph, the CVT engages and operates as it normally would[7]. “The auxiliary geartrain’s direct coupling ensures sufficiently brisk takeoff and initial acceleration”[7]. However, Aichi’s CVT can only handle 52 lb-ft of torque. This alone effectively negates itspotential for the U.S. market. Still, there are far more CVTs in production for 2000 than for 1999, and each major automobile show brings more announcements for new CVTs.New CVT ResearchAs recently as 1997, CVT research focused on the basic issues of drive belt design and power transmission. Now, as belts by VDT and other companies become sufficiently efficient, research focuses primarily on control and implementation of CVTs.Nissan Motor Co. has been a leader in CVT research since the 1970s. A recent study analyzing the slip characteristics of a metal belt CVT resulted in a simulation method for slip limits and torque capabilities of CVTs [8]. This has led to a dramatic improvement in drive belt technology, since CVTs can now be modeled and analyzed with computer simulations, resulting in faster development and moreefficient design. Nissan’s research on the torque limits of belt-drive CVTs has also led to the use of torque converters, which several companies have since implemented. The torque converter is designed to allow “creep,” the slow speed at which automatic transmission cars drive without driver-induced acceleration. The torque converter adds “improved creep capability during idling for improved driveability at very low speeds and easy launch on uphill grades” [9]. Nissan’s Extroid uses such a torque converter for “smooth starting, vibration suppression, and creep characteristics” [2].CVT control has recently come to the forefront of research; even a mechanically perfect CVT is worthless without an intelligent active control algorithm. Optimal CVT performance demands integrated control, such as the system developed by Nissan to “obtain the demanded drive torque with optimum fuel economy” [13]. The control system determines the necessary CVT ratio based on a target torque, vehicle speed, and desired fuel economy. Honda has also developed an integrated control algorithm for its CVTs, considering not only the engine’s thermal efficiency but also work loss from drivetrain accessories and the transmission itself [12]. Testing of Honda’s algorithm with a prototype vehicle resulted in a one percent fuel economy increase compared to a conventional algorithm. While not a dramatic increase, Honda claims that its algorithm is fundamentally sound, and thus will it become “one of the basic technologies for the next generation’s powerplant control” [12].Although CVTs are currently in production, many control issues still amount to a “tremendous number of trials and errors” [10]. One study focusing on numerical representation of power transmission showed that “both block tilting and pulley deformation meaningfully effected the pulley thrust ratio between the driving and the driven pulleys” [10]. Thus, the resultant model of CVT performance can be used in future applications for transmission optimization. As more studies are conducted, fundamental research such as this will become the legacy of CVT design, and research can become more specialized as CVTs become more refined.As CVTs move from research and development to assembly line, manufacturing research becomes more important. CVTs require several crucial, high-tolerance components in order to function efficiently; Honda studied one of these, the pulley piston, in 1998. Honda found that prototype pistons“experienced a drastic thickness reduction (32% at maximum) due to the conventional stretch forming method” [11]. A four-step forming process was developed to ensure “a greater and more uniform thickness increase” and thus greater efficiency and performance. Moreover, work-hardening during the forming process further increased the pulley piston’s strength [11].Size and weight of CVTs has long been a concern, since conventional automatics weigh far more than manual transmissions and CVTs outweigh automatics. Most cars equipped with automatic transmissions have a curb weight between 50 and 150 pounds heavier than the same cars with manual transmissions. To solve this problem, Audi is currently developing magnesium gearbox housings, a first for cars in its class. This results in nearly a 16 pound weight reduction over conventional automatics. [1]. Future Prospects for CVTsMuch of the existing literature is quick to admit that the automotive industry lacks a broad knowledge base regarding CVTs. Whereas conventional transmissions have been continuously refined and improved since the very start of the 20th century, CVT development is only just beginning. As infrastructure is built up along with said knowledge base, CVTs will become ever-more prominent in the automotive landscape. Even today’s CVTs, which represent first-generation designs at best, outperform conventional transmissions. Automakers who fail to develop CVTs now, while the field is still in its infancy, risk being left behind as CVT development and implementation continues its exponential growth. Moreover, CVTs are do not fall exclusively in the realm of IC engines.CVTs & Hybrid Electric VehiclesWhile CVTs will help to prolong the viability of internal combustion engines, CVTs themselves will certainly not fade if and when IC does. Several companies are currently studying implementation of CVTs with HEVs. Nissan recently developed an HEV with “fuel efficiency … more than double that of existing vehicles in the same class of driving performance” [14]. The electric motor avoids the low-speed/high torque problems often associated with CVTs, through an innovative double-motor system. At low speeds:A low-power traction motor is used as a substitute mechanism to accomplish thefunctions of launch and forward/reverse shift. This has made it possible to discontinueuse of a torque converter as the launch element and a planetary gearset and wet multiplateclutches as the shift mechanism. [14]Thus use of a CVT in a HEV is optimal: the electric portion of the power system avoids the low-speed problems of CVTs, while still retaining the fuel efficiency and power transmission benefits at high speeds.. Moreover, “the use of a CVT capable of handling high engine torque allows the system to be applied to more powerful vehicles” [14]. Obviously, automakers cannot develop individual transmissions for each car they sell; rather, a few robust, versatile CVTs must be able to handle a wide range of vehicles.Korean automaker Kia has proposed a rather novel approach to CVTs and their application to hybrids. Kia recently tested a system where “the CVT allows the engine to run at constant speed and the motor allows the engine to run at constant torque independent of driving conditions” [15]. Thus, both gasoline engine and electric motor always run at their optimal speeds, and the CVT adjusts as needed to accelerate the vehicle. Kia also presented a control system for this unified HEV/CVT combination that optimizes fuel efficiency for the new configuration.ConclusionToday, only a handful of cars worldwide make use of CVTs, but the applications and benefits of continuously variable transmissions can only increase based on today’s research and development. As automakers continue to develop CVTs, more and more vehicle lines will begin to use them. As development continues, fuel efficiency and performance benefits will inevitably increase; this will lead to increased sales of CVT-equipped vehicles. Increased sales will prompt further development and implementation, and the cycle will repeat ad infinitum. Moreover, increasing development will foster competition among manufacturers—automakers from Japan, Europe, and the U.S. are already either using or developing CVTs—which will in turn lower manufacturing costs. Any technology with inherent benefits will eventually reach fruition; the CVT has only just begun to blossom.Works Cited[1]S. Birch: “Audi takes CVT from 15th century to 21st century”. Automotive Engineering International,January 2000.[2]J. Yamaguchi: “Nissan’s Extroid CVT”. Automotive Engineering International, February 2000.[3]M.A. Kluger and D.R. Fussner: “An Overview of Current CVT Mechanisms, Forces andEfficiencies” SAE Paper No. 970688, in SAE SP-1241, Transmission and Driveline SystemsSymposium, pp. 81-88 SAE, 1997.[4]U.S. Environmental Protection Agency, /feg/findacar.htm.Accessed 4/15/00.[5]M. Boos and H. Mozer: “ECOTRONIC – The Continuously Variable ZF Transmission (CVT)” SAEPaper No. 970685, in SAE SP-1241, Transmission and Driveline Systems Symposium, pp. 61-67 SAE, 1997.[6]J.L. Broge: “GM Powertrain’s evolving transmissions”. Automotive Engineering International,November 1999.[7]J. Yamaguchi: “Two new CVTs for mini cars”. Automotive Engineering International, March 1999.[8]D. Kobayashi, Y. Mabuchi and Y. Katoh: “A Study on the Torque Capacity of a Metal Pushing V-Belt for CVTs” SAE Paper No. 980822, in SAE SP –1324, Transmission and Driveline Systems Symposium, pp. 31-39 SAE, 1998.[9]K. Abo, M. Kobayashi and M. Kurosawa: “Development of a Metal Belt Drive CVT Incorporating aTorque Converter for Use with 2-liter Class Engines” SAE Paper No. 980823, in SAE SP-1324, Transmission and Driveline Systems Symposium, pp. 41-48 SAE, 1998.[10]T. Miyazawa, T. Fujii, K. Nonaka and M. Takahashi: “Power Transmitting Mechanism of a DryHybrid V-Belt for a CVT – Advanced Numerical Model Considering Block Tilting and PulleyDeformation” SAE Paper No. 1999-01-0751, in SAE SP-1440, Transmission and Driveline Systems Symposium, pp. 143-153 SAE, 1999.[11]K. Ohya and H. Suzuki: “Development of CVT Pulley Piston Featuring Variable Thickness andWork-Hardening Technologies” SAE Paper No. 980826, in SAE SP-1324, Transmission andDriveline Systems Symposium, pp. 71-79 SAE, 1998.[12]S. Sakaguchi, E. Kimura and K. Yamamoto: “Development of an Engine-CVT Integrated ControlSystem” SAE Paper No. 1999-01-0754, in SAE SP-1440, Transmission and Driveline SystemsSymposium, pp. 171-179 SAE, 1999.[13]M. Yasuoka, M. Uchida, S. Katakura and T. Yoshino: “An Integrated Control Algorithm for anSI Engine and a CVT” SAE Paper No. 1999-01-0752, in SAE SP-1440, Transmission and Driveline Systems Symposium, pp. 155-160 SAE, 1999.[14]N. Hattori, S. Aoyama, S. Kitada and I. Matsuo: “Functional Design of a Motor Integrated CVTfor a Parallel HEV” SAE Paper No. 1999-01-0753, in SAE SP-1440, Transmission and Driveline Systems Symposium, pp. 161-167 SAE, 1999.[15] C. Kim, E. NamGoong, S. Lee, T. Kim and H. Kim: “Fuel Economy Optimization for ParallelHybrid Vehicles with CVT” SAE Paper No. 1999-01-1148, in SAE SP-1440, Transmission and Driveline Systems Symposium, pp. 337-343 SAE, 1999.。

自动变速器中英文对照外文翻译文献

自动变速器中英文对照外文翻译文献

中英文对照外文翻译文献(文档含英文原文和中文翻译)How Automatic Transmissions WorkIf you have ever driven a car with an automatic transmission, then you know that there are two big differences between an automatic transmission and a manual transmission:There is no clutch pedal in an automatic transmission car.There is no gear shift in an automatic transmission car. Once you put the transmission into drive, everything else is automatic.Both the automatic transmission (plus its torque converter) and a manual transmission (with its clutch) accomplish exactly the same thing, but they do it in totally different ways. It turns out that the way an automatic transmission does it is absolutely amazing!In this article, we'll work our way through an automatic transmission. We'll start with the key to the whole system: planetary gear sets. Thenwe'll see how the transmission is put together, learn how the controls work and discuss some of the intricacies involved in controlling a transmission.Some BasicsJust like that of a manual transmission, the automatic transmission's primary job is to allow the engine to operate in its narrow range of speeds while providing a wide range of output speeds.Without a transmission, cars would be limited to one gear ratio, and that ratio would have to be selected to allow the car to travel at the desired top speed. If you wanted a top speed of 80 mph, then the gear ratio would be similar to third gear in most manual transmission cars.You've probably never tried driving a manual transmission car using only third gear. If you did, you'd quickly find out that you had almost no acceleration when starting out, and at high speeds, the engine would be screaming along near the red-line. A car like this would wear out very quickly and would be nearly undrive able.So the transmission uses gears to make more effective use of the engine's torque, and to keep the engine operating at an appropriate speed.The key difference between a manual and an automatic transmission is that the manual transmission locks and unlocks different sets of gears to the output shaft to achieve the various gear ratios, while in an automatic transmission, the same set of gears produces all of the different gear ratios. The planetary gear set is the device that makes this possible in an automatic transmission.GearsThis automatic transmission uses a set of gears, called a compound planetary gear set, that looks like a single planetary gear set butactually behaves like two planetary gear sets combined. It has one ring gear that is always the output of the transmission, but it has two sun gears and two sets of planets.Let's look at some of the parts:First GearIn first gear, the smaller sun gear is driven clockwise by the turbine in the torque converter. The planet carrier tries to spin counterclockwise,but is held still by the one-way clutch (which only allows rotation in the clockwise direction) and the ring gear turns the output. The small gear has 30 teeth and the ring gear has 72, so the gear ratio is:Ratio = -R/S = - 72/30 = -2.4:1So the rotation is negative 2.4:1, which means that the output direction would be opposite the input direction. But the output direction is reallythe same as the input direction -- this is where the trick with the twosets of planets comes in. The first set of planets engages the second set, and the second set turns the ring gear; this combination reverses the direction. You can see that this would also cause the bigger sun gear to spin; but because that clutch is released, the bigger sun gear is free to spin in the opposite direction of the turbineSecond GearThis transmission does something really neat in order to get the ratio needed for second gear. It acts like two planetary gear sets connected to each other with a common planet carrier.The first stage of the planet carrier actually uses the larger sun gearas the ring gear. So the first stage consists of the sun (the smaller sun gear), the planet carrier, and the ring (the larger sun gear).The input is the small sun gear; the ring gear (large sun gear) is held stationary by the band, and the output is the planet carrier. so theformula is:1 + R/S = 1 + 36/30 = 2.2:1The planet carrier turns 2.2 times for each rotation of the small sun gear. At the second stage, the planet carrier acts as the input for the second planetary gear set, the larger sun gear (which is held stationary) acts as the sun, and the ring gear acts as the output, so the gear ratio is:1 / (1 + S/R) = 1 / (1 + 36/72) = 0.67:1To get the overall reduction for second gear, we multiply the first stage by the second, 2.2 x 0.67, to get a 1.47:1 reduction. This may sound wacky, but it works.Third GearMost automatic transmissions have a 1:1 ratio in third gear. You'll remember from the previous section that all we have to do to get a 1:1output is lock together any two of the three parts of the planetary gear. With the arrangement in this gear set it is even easier -- all we have todo is engage the clutches that lock each of the sun gears to the turbine.If both sun gears turn in the same direction, the planet gears lockup because they can only spin in opposite directions. This locks the ring gear to the planets and causes everything to spin as a unit, producing a 1:1 ratio. OverdriveBy definition, an overdrive has a faster output speed than input speed.It's a speed increase. In this transmission, engaging the overdrive accomplishes two things at once. If you read How Torque Converters Work,you learned about lockup torque converters. In order to improve efficiency, some cars have a mechanism that locks up the torque converter so that the output of the engine goes straight to the transmission.In this transmission, when overdrive is engaged, a shaft that is attached to the housing of the torque converter (which is bolted to the flywheel of the engine) is connected by clutch to the planet carrier. The small sungear freewheels, and the larger sun gear is held by the overdrive band. Nothing is connected to the turbine; the only input comes from theconverter housing. Let's go back to our chart again, this time with the planet carrier for input, the sun gear fixed and the ring gear for output.Ratio = 1 / (1 + S/R) = 1 / ( 1 + 36/72) = 0.67:1So the output spins once for every two-thirds of a rotation of the engine. If the engine is turning at 2000 rotations per minute (RPM), the outputspeed is 3000 RPM. This allows cars to drive at freeway speed while the engine speed stays nice and slow.ReverseReverse is very similar to first gear, except that instead of the small sun gear being driven by the torque converter turbine, the bigger sun gear is driven, and the small one freewheels in the opposite direction. The planet carrier is held by the reverse band to the housing. So, according to our equations from the last page, we have:Ratio = -R/S = 72/36 = 2.0:1So the ratio in reverse is a little less than first gear in this transmission. Gear RatiosThis transmission has four forward gears and one reverse gear. Let's summarize the gear ratios, inputs and outputs:Gear Input Output FixedGear Ratio1st 30-tooth sun72-toothringPlanetcarrier2.4:12nd30-tooth sunPlanetcarrier36-toothring2.2:1Planetcarrier72-toothring36-toothsun0.67:1Total 2nd 1.47:13rd30- and 36-tooth suns72-toothring1.0:1OD Planet 72-tooth 36-tooth 0.67:1carrier ring sunRever se 36-tooth sun72-toothringPlanetcarrier-2.0:1Hydraulic SystemThe automatic transmission in your car has to do numerous tasks. You may not realize how many different ways it operates. For instance, here are some of the features of an automatic transmission:If the car is in overdrive (on a four-speed transmission), the transmission will automatically select the gear based on vehicle speed and throttle pedal position.If you accelerate gently, shifts will occur at lower speeds than if you accelerate at full throttle.If you floor the gas pedal, the transmission will downshift to the next lower gear.If you move the shift selector to a lower gear, the transmission will downshift unless the car is going too fast for that gear. If the car is going too fast, it will wait until the car slows down and then downshift.If you put the transmission in second gear, it will never downshift or up shift out of second, even from a complete stop, unless you move the shift lever.You've probably seen something that looks like this before. It isreally the brain of the automatic transmission, managing all of these functions and more. The passageways you can see route fluid to all the different components in the transmission. Passageways molded into the metal are an efficient way to route fluid; without them, many hoses would be needed to connect the various parts of the transmission. First, we'll discuss the key components of the hydraulic system; then we'll see how they work together.The PumpAutomatic transmissions have a neat pump, called a gear pump. The pump is usually located in the cover of the transmission. It draws fluid from a sump in the bottom of the transmission and feeds it to the hydraulic system. It also feeds the transmission cooler and the torque converter.The inner gear of the pump hooks up to the housing of the torque converter, so it spins at the same speed as the engine. The outer gear is turned by the inner gear, and as the gears rotate, fluid is drawn up fromthe sump on one side of the crescent and forced out into the hydraulic system on the other side.The GovernorThe governor is a clever valve that tells the transmission how fast thecar is going. It is connected to the output, so the faster the car moves,the faster the governor spins. Inside the governor is a spring-loaded valve that opens in proportion to how fast the governor is spinning -- the faster the governor spins, the more the valve opens. Fluid from the pump is fed to the governor through the output shaft.The faster the car goes, the more the governor valve opens and the higher the pressure of the fluid it lets through.Valves and ModulatorsThrottle Valve or ModulatorTo shift properly, the automatic transmission has to know how hard the engine is working. There are two different ways that this is done. Somecars have a simple cable linkage connected to a throttle valve in the transmission. The further the gas pedal is pressed, the more pressure isput on the throttle valve. Other cars use a vacuum modulator to apply pressure to the throttle valve. The modulator senses the manifold pressure, which drops when the engine is under a greater load.Manual ValveThe manual valve is what the shift lever hooks up to. Depending on which gear is selected, the manual valve feeds hydraulic circuits that inhibitcertain gears. For instance, if the shift lever is in third gear, it feedsa circuit that prevents overdrive from engaging.Shift ValvesShift valves supply hydraulic pressure to the clutches and bands to engage each gear. The valve body of the transmission contains several shift valves. The shift valve determines when to shift from one gear to the next. For instance, the 1 to 2 shift valve determines when to shift from first to second gear. The shift valve is pressurized with fluid from the governor on one side, and the throttle valve on the other. They are supplied with fluid by the pump, and they route that fluid to one of two circuits to control which gear the car runs in.The shift valve will delay a shift if the car is accelerating quickly. If the car accelerates gently, the shift will occur at a lower speed. Let's discuss what happens when the car accelerates gently.As car speed increases, the pressure from the governor builds. Thisforces the shift valve over until the first gear circuit is closed, and the second gear circuit opens. Since the car is accelerating at light throttle, the throttle valve does not apply much pressure against the shift valve.When the car accelerates quickly, the throttle valve applies morepressure against the shift valve. This means that the pressure from the governor has to be higher (and therefore the vehicle speed has to be faster) before the shift valve moves over far enough to engage second gear.Each shift valve responds to a particular pressure range; so when the car is going faster, the 2-to-3 shift valve will take over, because thepressure from the governor is high enough to trigger that valve.Electronic ControlsElectronically controlled transmissions, which appear on some newer cars, still use hydraulics to actuate the clutches and bands, but each hydraulic circuit is controlled by an electric solenoid. This simplifies the plumbing on the transmission and allows for more advanced control schemes.自动变速器如何工作如果你曾经驾驶过一辆带着自动变速器的车, 那么你就知道自动变速器和手动变速器之间有很大的不同:在一个带着自动变速器的汽车中没有离合器踏板。

变速器(英文版文献)

变速器(英文版文献)

Transmission (mechanics)A transmission or gearbox provides speed and torque conversions from a rotating power source to another device using gear ratios. In British English the term transmission refers to the whole drive train, including gearbox, clutch, prop shaft (for rear-wheel drive), differential and final drive shafts. The most common use is in motor vehicles, where the transmission adapts the output of the internal combustion engine to the drive wheels. Such engines need to operate at a relatively high rotational speed, which is inappropriate for starting, stopping, and slower travel. The transmission reduces the higher engine speed to the slower wheel speed, increasing torque in the process. Transmissions are also used on pedal bicycles, fixed machines, and anywhere else rotational speed and torque needs to be adapted.Often, a transmission will have multiple gear ratios (or simply "gears"), with the ability to switch between them as speed varies. This switching may be done manually (by the operator), or automatically. Directional (forward and reverse) control may also be provided. Single-ratio transmissions alsoexist, which simply change the speed and torque (and sometimes direction) of motor output.In motor vehicle applications, the transmission will generally be connected to the crankshaft of the engine. The output of the transmission is transmitted via driveshaft to one or more differentials, which in turn drive the wheels. While a differential may also provide gear reduction, its primary purpose is to change the direction of rotation.Conventional gear/belt transmissions are not the only mechanism for speed/torque adaptation. Alternative mechanisms include torque converters and power transformation (e.g., diesel-electric transmission, hydraulic drive system, etc.). Hybrid configurations also exist.ExplanationEarly transmissions included the right-angle drives and other gearing in windmills, horse-powered devices, and steam engines, in support of pumping, milling, and hoisting.Most modern gearboxes are used to increase torque while reducing the speed of a prime mover output shaft (e.g. a motor crankshaft). This means that the output shaft of a gearbox willrotate at slower rate than the input shaft, and this reduction in speed will produce a mechanical advantage, causing an increase in torque. A gearbox can be setup to do the opposite and provide an increase in shaft speed with a reduction of torque. Some of the simplest gearboxes merely change the physical direction in which power is transmitted.Many typical automobile transmissions include the ability to select one of several different gear ratios. In this case, most of the gear ratios (often simply called "gears") are used to slow down the output speed of the engine and increase torque. However, the highest gears may be "overdrive" types that increase the output speed.UsesGearboxes have found use in a wide variety of different—often stationary—applications, such as wind turbines.Transmissions are also used in agricultural, industrial, construction, mining and automotive equipment. In addition to ordinary transmission equipped with gears, such equipment makes extensive use of the hydrostatic drive and electrical adjustable-speed drives.SimpleThe simplest transmissions, often called gearboxes to reflect their simplicity (although complex systems are also called gearboxes in the vernacular), provide gear reduction (or, more rarely, an increase in speed), sometimes in conjunction with a right-angle change in direction of the shaft (typically in helicopters, see picture). These are often used on PTO-powered agricultural equipment, since the axial PTO shaft is at odds with the usual need for the driven shaft, which is either vertical (as with rotary mowers), or horizontally extending from one side of the implement to another (as with manure spreaders, flail mowers, and forage wagons). More complex equipment, such as silage choppers and snowblowers, have drives with outputs in more than one direction.The gearbox in a wind turbine converts the slow, high-torque rotation of the turbine into much faster rotation of the electrical generator. These are much larger and more complicated than the PTO gearboxes in farm equipment. They weigh several tons and typically contain three stages to achieve an overall gear ratio from 40:1 to over 100:1, depending on the size of the turbine. (For aerodynamic and structuralreasons, larger turbines have to turn more slowly, but the generators all have to rotate at similar speeds of several thousand rpm.) The first stage of the gearbox is usually a planetary gear, for compactness, and to distribute the enormous torque of the turbine over more teeth of the low-speed shaft. Durability of these gearboxes has been a serious problem for a long time.Regardless of where they are used, these simple transmissions all share an important feature: the gear ratio cannot be changed during use. It is fixed at the time the transmission is constructed.For transmission types that overcome this issue, see Continuously Variable Transmission, also known as CVT.Multi-ratio systemsMany applications require the availability of multiple gear ratios. Often, this is to ease the starting and stopping of a mechanical system, though another important need is that of maintaining good fuel efficiency.Automotive basicsThe need for a transmission in an automobile is aconsequence of the characteristics of the internal combustion engine. Engines typically operate over a range of 600 to about 7000 revolutions per minute (though this varies, and is typically less for diesel engines), while the car's wheels rotate between 0 rpm and around 1800 rpm.Furthermore, the engine provides its highest torque outputs approximately in the middle of its range, while often the greatest torque is required when the vehicle is moving from rest or traveling slowly. Therefore, a system that transforms the engine's output so that it can supply high torque at low speeds, but also operate at highway speeds with the motor still operating within its limits, is required. Transmissions perform this transformation.Many transmissions and gears used in automotive and truck applications are contained in a cast iron case, though more frequently aluminium is used for lower weight especially in cars. There are usually three shafts: a mainshaft, a countershaft, and an idler shaft.The mainshaft extends outside the case in both directions: the input shaft towards the engine, and the output shaft towards the rear axle (on rear wheel drive cars- front wheel drives generally have the engine and transmission mountedtransversely, the differential being part of the transmission assembly.) The shaft is suspended by the main bearings, and is split towards the input end. At the point of the split, a pilot bearing holds the shafts together. The gears and clutches ride on the mainshaft, the gears being free to turn relative to the mainshaft except when engaged by the clutches.Types of automobile transmissions include manual, automatic or semi-automatic transmission.ManualMain article: Manual transmissionManual transmission come in two basic types:a simple but rugged sliding-mesh or unsynchronized / non-synchronous system, where straight-cut spur gear sets are spinning freely, and must be synchronized by the operator matching engine revs to road speed, to avoid noisy and damaging "gear clash", and the now common constant-mesh gearboxes which can include non-synchronised, or synchronized / synchromesh systems, where diagonal cut helical (and sometimes double-helical) gear sets are constantly "meshed" together, and a dog clutch is used for changing gears. On synchromesh boxes, friction cones or "synchro-rings" are used in addition to the dog clutch.The former type is commonly found in many forms of racing cars, older heavy-duty trucks, and some agricultural equipment.Manual transmissions are the most common type outside North America and Australia. They are cheaper, lighter, usually give better performance, and fuel efficiency (although the latest sophisticated automatic transmissions may yield results slightly better than the ones yielded by manual transmissions). It is customary for new drivers to learn, and be tested, on a car with a manual gear change. In Malaysia, Denmark and Poland all cars used for testing (and because of that, virtually all those used for instruction as well) have a manual transmission. In Japan, the Philippines, Germany, Italy, Israel, the Netherlands, Belgium, New Zealand, Austria, Bulgaria, the UK, Ireland, Sweden, Estonia, France, Spain, Switzerland, the Australian states of Victoria and Queensland, Finland and Lithuania, a test pass using an automatic car does not entitle the driver to use a manual car on the public road; a test with a manual car is required.Manual transmissions are much more common than automatic transmissions in Asia, Africa, South America and Europe.Most manual transmissions include both synchronized andunsynchronized gearing, such as a reverse gear and a low-speed "granny gear", both of which can only be shifted into when stopped. Shifting from granny gear to a low synchronized gear is generally available while in motion, while shifting out of reverse to any other gear typically requires the vehicle to be stopped.Non-synchronousMain article: Non-synchronous transmissionsThere are commercial applications engineered with designs taking into account that the gear shifting will be done by an experienced operator. They are a manual transmission, but are known as non-synchronized transmissions. Dependent on country of operation, many local, regional, and national laws govern the operation of these types of vehicles (see Commercial Driver's License). This class may include commercial, military, agricultural, or engineering vehicles. Some of these may use combinations of types for multi-purpose functions. An example would be a PTO, or power-take-off gear. The non-synchronous transmission type requires an understanding of gear range, torque, engine power, and multi-functional clutch and shifter functions. Also see Double-clutching, and Clutch-brakesections of the main article at non-synchronous transmissionsAutomaticMain article: Automatic transmissionEpicyclic gearing or planetary gearing as used in an automatic transmission.Most modern North American and Australian and many larger, high specification European and Japanese cars have an automatic transmission that will select an appropriate gear ratio without any operator intervention. They primarily use hydraulics to select gears, depending on pressure exerted by fluid within the transmission assembly. Rather than using a clutch to engage the transmission, a fluid flywheel, or torque converter is placed in between the engine and transmission. It is possible for the driver to control the number of gears in use or select reverse, though precise control of which gear is in use may or may not be possible.Automatic transmissions are easy to use. However, in the past, automatic transmissions of this type have had a number of problems; they were complex and expensive, sometimes had reliability problems (which sometimes caused more expenses in repair), have often been less fuel-efficient than their manualcounterparts (due to "slippage" in the torque converter), and their shift time was slower than a manual making them uncompetitive for racing. With the advancement of modern automatic transmissions this has changed.Attempts to improve the fuel efficiency of automatic transmissions include the use of torque converters which lock up beyond a certain speed, or in the higher gear ratios, eliminating power loss, and overdrive gears which automatically actuate above certain speeds; in older transmissions both technologies could sometimes become intrusive, when conditions are such that they repeatedly cut in and out as speed and such load factors as grade or wind vary slightly. Current computerized transmissions possess very complex programming to both maximize fuel efficiency and eliminate any intrusiveness.For certain applications, the slippage inherent in automatic transmissions can be advantageous; for instance, in drag racing, the automatic transmission allows the car to be stopped with the engine at a high rpm (the "stall speed") to allow for a very quick launch when the brakes are released; in fact, a common modification is to increase the stall speed of the transmission. This is even more advantageous forturbocharged engines, where the turbocharger needs to be kept spinning at high rpm by a large flow of exhaust in order to keep the boost pressure up and eliminate the turbo lag that occurs when the engine is idling and the throttle is suddenly openedSemi-automaticMain article: Semi-automatic transmissionThe creation of computer control also allowed for a sort of cross-breed transmission where the car handles manipulation of the clutch automatically, but the driver can still select the gear manually if desired. This is sometimes called a "clutchless manual," or "automated manual" transmission. Many of these transmissions allow the driver to give full control to the computer. They are generally designed using manual transmission "internals", and when used in passenger cars, have synchromesh operated helical constant mesh gear sets.Specific type of this transmission includes: Easytronic, and Geartronic.A "dual-clutch" transmission uses two sets of internals which are alternately used, each with its own clutch, so that only the clutches are used during the actual "gearchange".Specific type of this transmission includes: Direct-ShiftGearbox.There are also sequential transmissions which use the rotation of a drum to switch gears.Bicycle gearingMain articles: Bicycle gearing, Derailleur gears, and Hub gear Bicycles usually have a system for selecting different gear ratios. There are two main types: derailleur gears and hub gears. The derailleur type is the most common, and the most visible, using sprocket gears. Typically there are several gears available on the rear sprocket assembly, attached to the rear wheel. A few more sprockets are usually added to the front assembly as well. Multiplying the number of sprocket gears in front by the number to the rear gives the number of gear ratios, often called "speeds".Hub gears use epicyclic gearing and are enclosed within the axle of the rear wheel. Because of the small space, they typically offer fewer different speeds, although at least one has reached 14 gear ratios and Fallbrook Technologies manufactures a transmission with technically infinite ratios.Causes for failure of bicycle gearing include: worn teeth, damage caused by a faulty chain, damage due to thermal expansion,broken teeth due to excessive pedaling force, interference by foreign objects, and loss of lubrication due to negligence.Uncommon typesDual clutch transmissionMain article: Dual clutch transmissionThis arrangement is also sometimes known as a direct shift gearbox or powershift gearbox. It seeks to combine the advantages of a conventional manual shift with the qualities of a modern automatic transmission by providing different clutches for odd and even speed selector gears. When changing gear, the engine torque is transferred from one gear to the other continuously, so providing gentle, smooth gear changes without either losing power or jerking the vehicle. Gear selection may be manual, automatic (depending on throttle/speed sensors), or a 'sports' version combining both options.Continuously variableMain article: Continuously variable transmissionThe Continuously Variable Transmission (CVT) is a transmission in which the ratio of the rotational speeds of twoshafts, as the input shaft and output shaft of a vehicle or other machine, can be varied continuously within a given range, providing an infinite number of possible ratios.The continuously variable transmission (CVT) should not be confused with the Infinitely Variable Transmission (IVT) (See below).The other mechanical transmissions described above only allow a few different gear ratios to be selected, but this type of transmission essentially has an infinite number of ratios available within a finite range. The continuously variable transmission allows the relationship between the speed of the engine and the speed of the wheels to be selected within a continuous range. This can provide even better fuel economy if the engine is constantly running at a single speed. The transmission is in theory capable of a better user experience, without the rise and fall in speed of an engine, and the jerk felt when poorly changing gears.Infinitely variableThe IVT is a specific type of CVT that has an infinite range of input/output ratios in addition to its infinite number of possible ratios; this qualification for the IVT implies thatits range of ratios includes a zero output/input ratio that can be continuously approached from a defined 'higher' ratio. A zero output implies an infinite input, which can be continuously approached from a given finite input value with an IVT. [Note: remember that so-called 'low' gears are a reference to low ratios of output/input, which have high input/output ratios that are taken to the extreme with IVT's, resulting in a 'neutral', or non-driving 'low' gear limit.] Most (if not all) IVT's result from the combination of a CVT with an epicyclic gear system (which is also known as a planetary gear system) that facilitates the subtraction of one speed from another speed within the set of input and planetary gear rotations. This subtraction only needs to result in a continuous range of values that includes a zero output; the maximum output/input ratio can be arbitrarily chosen from infinite practical possibilities through selection of extraneous input or output gear, pulley or sprocket sizes without affecting the zero output or the continuity of the whole system. Importantly, the IVT is distinguished as being 'infinite' in its ratio of high gear to low gear within its range; high gear is infinite times higher than low gear. The IVT is always engaged, even during its zero output adjustment.The term 'infinitely variable transmission' does not imply reverse direction, disengagement, automatic operation, or any other quality except ratio selectability within a continuous range of input/output ratios from a defined minimum to an undefined, 'infinite' maximum. This means continuous range from a defined output/input to zero output/input ratio.Electric variableThe Electric Variable Transmission (EVT) is a transmission that achieves CVT action and in addition can use separate power inputs to produce one output. An EVT usually is executed in design with an epicyclic differential gear system (which is also known as a planetary gear system). The epicyclic differential gearing performs a "power-split" function, directly connecting a portion of the mechanical power directly through the transmission and splitting off a portion for subsequent conversion to electrical power via a motor/generator. Hence, the EVT is called a Power Split Transmission (PST) by some.The directly connected portion of the power travelling through the EVT is referred to as the "mechanical path". The remaining power travels down the EVT's "electrical path". Thatpower may be recombined at the output of the transmission or stored for later, more opportune use via a second motor/generator (and energy storage device) connected to the transmission output.The pair of motor/generators forms an Electric Transmission in its own right, but at a lower capacity, than the EVT it is contained within. Generally the Electric Transmission capacity within the EVT is a quarter to a half of the capacity of the EVT. Good reasons to use an EVT instead of an equivalently-sized Electrical transmission is that the mechanical path of the EVT is more compact and efficient than the electrical path.The EVT is the essential method for transmitting power in some hybrid vehicles, enabling an Internal Combustion Engine (ICE) to be used in conjunction with motor/generators for vehicle propulsion, and having the ability to control the portion of the mechanical power used directly for propelling the vehicle and the portion of mechanical power that is converted to electric power and recombined to drive the vehicle.The EVT and power sources are controlled to provide a balance between the power sources that increases vehicle fueleconomy while providing advantageous performance when needed. The EVT may also be used to provide electrically generated power to charge large storage batteries for subsequent electric motor propulsion as needed, or to convert vehicle kinetic energy to electricity through 'regenerative braking' during deceleration. Various configurations of power generation, usage and balance can be implemented with a EVT, enabling great flexibility in propelling hybrid vehicles.The Toyota single mode hybrid and General Motor 2 Mode hybrid are production systems that use EVTs. The Toyota system is in the Prius, Highlander, and Lexus RX400h and GS450h models. The GM system is the Allison Bus hybrid powertrains and are in the Tahoe and Yukon models. The Toyota system uses one power-split epicyclic differential gearing system over all driving conditions and is sized with an electrical path rated at approximately half the capacity of the EVT. The GM system uses two different EVT ranges: one designed for lower speeds with greater mechanical advantage, and one designed for higher speeds, and the electrical path is rated at approximately a quarter of the capacity of the EVT. Other arrangements are possible and applications of EVT's are growing rapidly in number and variety.EVT's are capable of continuously modulating output/input speed ratios like mechanical CVT's, but offer the distinct difference and benefit of being able to also apportion power from two different sources to one output.HydrostaticSee also Continuously variable transmission > Hydrostatic CVTs Hydrostatic transmissions transmit all power hydraulically, using the components of hydraulic machinery. Hydrostatic transmissions do not make use of the hydrodynamic forces of the fluid flow. There is no solid coupling of the input and output. The transmission input drive is a central hydraulic pump and final drive unit(s) is/are a hydraulic motor, or hydraulic cylinder (see:swashplate. Both components can be placed physically far apart on the machine, being connected only by flexible hoses. Hydrostatic drive systems are used on excavators, lawn tractors, forklifts, winch drive systems, heavy lift equipment, agricultural machinery, etc. An arrangement for motor-vehicle transmission was probably used on the Ferguson F-1 P99 racing car in about 1961.The Human Friendly Transmission of the Honda DN-01 is hydrostatic.HydrodynamicIf the hydraulic pump and/or hydraulic motor make use of the hydrodynamic effects of the fluid flow, i.e. pressure due to a change in the fluid's momentum as it flows through vanes in a turbine. The pump and motor usually consist of rotating vanes without seals and are typically placed in close proximity. The transmission ratio can be made to vary by means of additional rotating vanes, an effect similar to varying the pitch of an airplane propeller.The torque converter in most automotive automatic transmissions is, in itself, a hydrodynamic transmission.It was possible to drive the Dynaflow transmission without shifting the mechanical gears.Hydrodynamic transmissions are used in many passenger rail vehicles. In this application the advantage of smooth power delivery may outweigh the reduced efficiency caused by turbulence energy losses in the fluid.ElectricElectric transmissions convert the mechanical power of the engine(s) to electricity with electric generators and convertit back to mechanical power with electric motors. Electrical or electronic adjustable-speed drive control systems are used to control the speed and torque of the motors. If the generators are driven by turbines, such arrangements are called turbo-electric. Likewise installations powered by diesel-engines are called diesel-electric. Diesel-electric arrangements are used on many railway locomotives, ships and large mining trucks.。

汽车变速器的设计外文文献翻译、中英文翻译、外文翻译

汽车变速器的设计外文文献翻译、中英文翻译、外文翻译

汽车变速器的设计外文文献翻译、中英文翻译、外文翻译A manual n。

also known as a standard n。

XXX。

It consistsof gears。

synchros。

roller bearings。

shafts。

and gear selectors。

The main clutch assembly is used to engage and disengage the engine from XXX gears are used to select the desired。

and the sector fork moves gears from one to another using the gearshift knob。

Synchros are used to slow the gear to a。

before it is XXX。

The counter shaft holds the gears in place and against the main input and output shaft。

Unlike automatic ns。

XXX。

as there isno XXX。

Note: XXX "n Shifter" was deleted as it had no XXX.)XXX have four to six forward gears and one reverse gear。

However。

some cars may have up to eight forward gears。

while semi trucks XXX by the number of forward gears。

such as a 5-speed standard n.The n of a standard n includes three shafts: the input shaft。

汽车变速器的设计外文文献翻译、中英文翻译、外文翻译

汽车变速器的设计外文文献翻译、中英文翻译、外文翻译

本科毕业设计(论文)英文资料翻译*****指导教师:孙飞豹(副教授)学科、专业:车辆工程沈阳理工大学应用技术学院2011年12月20日transmission used in automobilesA standard transmission or manual transmission is the traditional type of transmission used in automobiles. The manual or standard transmission consists of a series of gears, synchros, roller bearings, shafts and gear selectors. The main clutch assembly is used to engage and disengage the engine from the transmission. Heliacal cut gears are used to select the ratio desired the sector fork move gears from one to another by using the gearshift knob. Synchros are used to slow the gear to a stop before it is engaged to avoid gear grinding, the counter shaft hold the gears in place and against the main input and output shaft. A stick shift transmission has no torque converter so there is no need for a transmission cooler. A stick shift transmission needs a simple fluid change for proper service. (there is no transmission filter in a stick shift transmission).Transmission ShifterMost manual transmissions have one reverse gear and four to six forward gears. Some cars also have eight forward gears while thirteen to twenty-four gears are present in semi trucks. To differentiate among the available standard transmissions, they are addressed by the number of forward gears. For example, if the standard transmission has five gears, it will be referred to as 5-speed standard transmission or 5-speed standard.Typical Standard Transmission ConfigurationInside the transmission shafts contain all forward and reverse gears. Most transmissions contain three shafts: input shaft, output shaft and counter or lay shaft. Other than standard transmission, there are other transmissions like continuously variable transmission, automatic transmission and semi-automatic transmission. In the manual transmission, a pair of gears inside the transmission selects the gear ratios. Whereas, in an automatic transmission, combination of brake bands and clutch packs control the planetary gear which selects the gear ratio.If there is a provision to select a gear ratio manually in automatic transmissions, the system is called a semi-automatic transmission. The driver can select from any of the gears at any pointof time. In some automobiles like racing cars and motorcycles that have standard transmissions, the driver can select the preceding or the following gear ratio with no clutch operation needed. This type of standard transmission is known as sequential transmission. In this transmission the clutch is still used for initial take off.Clutch and Flywheel AssemblyThe main clutch plays the role of a coupling device which separates the transmission and the engine. If the clutch is absent and the car comes to a stop the engine will stall. In automobiles, the clutch can be operated with the help of a pedal located on the floor of the vehicle. In an automatic transmission instead of a clutch, a torque converter is used to separate the transmission and engine.Typical Stick Shift PatternsA desired gear can be selected by a lever which is usually located on the floor in between the driver and passenger seat. This selector lever is called the gear lever or gear selector or gear shift or shifter. This gear stick can be made to move in right, left, forward and backward direction. When the gear is placed on the N position or neutral position, no gear will be selected. To move the car in the backward direction, the R gear or reverse gear should be selected.Standard transmissions are more efficient and less expensive to produce than automatic transmissions. A Standard transmission is about 15% more efficient compared to an automatic transmission. Standard transmissions are generally stronger than automatic transmissions and off road vehicles take advantage of a direct gear selection so they can withstand rough conditions. Less active cooling is also required in manual transmission system because less power is wasted.●Popular Problem ChecksCar will not go into gearClutch disc is broken completelyInternal transmission damageFailed clutch master cylinderSeized clutch slave cylinderBroken clutch fork pivotBroken clutch cableCar goes into gear but it fades out or is slippingClutch is worn out and needs replacementClutch is oil soaked from a external engine oil leakCar makes grinding noise while operating or shifting gearsOne of the roller or thrust bearings has failedThe gear synchro is worn out not forcing the gear stop before it is engaged causing a grinding gear.A counter or main shaft bearing has failed causing misalignment of the gears●Troubleshooting Noise and ProblemsIf the vehicle is running and a whirring sound is heard, then it goes away when the clutch is depressed, the transmission input bearing has failed.If the transmission is quiet in neutral but when you depress the clutch a squeaking noise is observed, a clutch throw out bearing has failed.Tips:Never let little noises go unattended; a small noise can cause a large noise and transmission operation failure. Never overload a vehicle or tow beyond the capacity this can cause premature transmission failure.汽车变速器汽车传统变速器是那种标准的手动变速器。

汽车变速器变速箱外文文献翻译、中英文翻译、外文翻译

汽车变速器变速箱外文文献翻译、中英文翻译、外文翻译

TRANSMISSIONOf all transmission technologies, the manual gearbox is the most efficient; around 96 per cent of the energy that is put in comes out of the other end. But not everyone can drive one or wants to. Because you have to dip the clutch pedal, it is less comfortable to drive in heavy traffic. It makes the driver tired and the torque interruptions’ head-nod effect on passengers can be wearing.The driver's clutch control and corresponding torque interruptions are also the manuals weak point. When accelerating up through the gearbox, each up-shift requires the driver to cut the torque momentarily by lifting the gas pedal and dipping the clutch. It may just take a second to complete the operation, but during this time the vehicle is losing speed and acceleration.At the opposite end of the spectrum is the traditional automatic. The modern transmission is by far, the most complicated mechanical component in today’s automobile. It is a type of transmission that shifts itself .A fluid coupling or torque converter is used instead of a manually operated clutch to connect the transmission to the engine.There are two basic types of automatic transmissions based on whetherthe vehicle is rear wheel drive . On a rear wheel drive car , the transmission is usually mounted to the back of the engine and is located under the hump in the center of the floorboard alongside the gas pedal position . A drive shaft connects the rear of the transmission to the final drive which is located in the rear axle and is used to send power to the rear wheel. Power flow on this system is simple and straight forward going from the engine, through the torque converter , then through the transmission and driver shaft until it reaches the final driver where it is split and sent to the two rear wheel .On a front wheel drive car, the transmission is usually combined .With the final drive to from what is called a transaxle. The engine on a front wheel driver car is usually mounted sideways in the car with the transaxle tucked under it onthe side of the engine facing the rear of the car. Front axles are connected directly to the transaxle and provide power to the front wheels. In this example, power flows from the engine through the torque converter to a large chain that sends the power through a 180 degree turn to the transmission that is along side the engine. From there,The power is routed through the transmission to the final drive where it is split and sent to the two front wheels through the drive axles.There are a number of other arrangements including front drive vehicles where the engine is mounted front to back instead of sideways and there are other systems that drive all four wheels but the two systems described here are by far the most popular. A must less popular rear drive arrangement has the transmission mounted to the final drive at the rear and is connected by a drive shaft to the torque converter which is still mounted on the engine. This system is found on the new corvette and is used in order to balance the weight evenly between the front and rear wheels for improved performance and handling. Another rear drive system mounts everything, the engine, transmission and final drive in the rear. This rear engine arrangement is popular on the Porsche.The modern automatic transmission consists of many components and systems that are designed to work together in a symphony of planetary gear sets, the hydraulic system, seals and gaskets, the torque converter, the governor and the modulator or throttle cable and computer consider being an art form.On the automobile planet gear mainly uses in two places, one is the driving axle reduction gear, two is the automatic transmission. Very many net friends all want to know that, the planet gear has any function, why automobile must have it . We knew very well the gear major part all rotates the spool thread fixed gear. For example mechanical type clock and watch, above all gears although all in make the rotation, but their rotation center (with center of a circle position superposition) often installs through the bearing on the cabinet, therefore, their rotating axis all is the relative cabinet fixed, thus also is called "dead axle gear" . Has must have surely moves, the corresponding place, some kind of not that manner knows very well is called "planet gear" the gear, their rotation spool thread is not fixed, but is installs the support which may rotate in (blue color) on(in chart black part is shell, yellow expression bearing). The planet gear (green) besides can look like the dead axle gear such to revolve own rotating axis (B-B) to rotate, their rotating axis also (is called planet) along with the blue color support to circle other gears the spool thread (A-A) to rotate. Circles oneself spool thread the rotation to be called "rotation", circles other gear spool threads the rotation to be called "revolution", looks like in solar system planet such, therefore acquires fame.The spool thread fixed gear drive principle is very simple, meshes mutually in a pair in the gear, some gear takes the driving pulley, the power spreads from its there, another gear takes the driven wheel, the power outputs from it toward outside. Also some gears only take the stopover station, at the same time meshes with the driving pulley, one side meshes in addition with the driven wheel, the power passes from its there.In contains the planet gear in the gear system, the situation was different. Because has the planet frame, in other words, may have three rotating axes permissions power input/Output, but also may use the coupling or the brake and so on method. in needs time limits axis the rotation, is left over two axes to carry on the transmission, as the matter stands, meshes mutually between the gear relations may have the many kinds of combinations: The power from sun gear input, outputs from other sun gear, the planet put through brake mechanism has checked dies; Power from sun gear input, from planet output, moreover a sun gear ecks dies; The power from a planet input, outputs from sun gear, moreover a sun gear checks dies; Two powers separately from two sun gears inputs, after synthesis from planet output; Two powers separately from the planet and sun gear input, after the synthesis output from other sun gear; The power from sun gear input, divides two groups outputs from other sun gear and the planet frame; The power from a planet input, divides two groups to output from two sun gears;Its shift quality is good thanks to its torque converter, but efficiency is relatively poor despite recent advances. Because of this, a lot of the current research is trying to find an efficient alternative to the conventional automatic.The main technologies are continuously variable transmissions (CVTs); dualclutch transmissions (DCTs) and automated manual transmission (AMTs).They all offer different benefits over the conventional planetary automatic.The CVT uses a belt chain or torodial shaped dish drive to vary an infinite number of gear ratios. It has improved efficiency and cost when compared to conventional automatics. Its advantage comes from its simplicity. It consists of very few components;usually a rubber or metal-link belt;a hydraulically operated driving pulley, a mechanical torque-sensing driving pulley, microprocessors and some sensors.The transmission works by varying the distance between the face of the two main pulleys. The pulleys have V-shaped grooves in which the connecting the belt rides. One side of the pulley is fixed axially; the other side moves, actuated by hydraulics.When actuated, the cylinder can increase or reduce the amount of space between the two sides of the pulley. This allows the belt to ride lower or higher along the walls of the pulley, depending on driving conditions. This changes the gear ratio. A torodial-type design works in a similar way but runs an discs and power- rollersThe "step less" nature of its design is CVT's biggest draw for automotive engineers .Because of this, a CVT can work to keep the engine in its optimum power range, thereby increasing efficiency and mileage. A CVT can convert every point on the equine’s operating curve to a corresponding point on its own operating curve.The transmission is most popular with Japanese carmakers and Japanese supplier JATCO is a major producer. But in the US and Europe driving styles are different. Uptake has been slow despite Audi and other manufacturers having Offered CVT operations on their ranges.The DCT is, in effect, two manual gearboxes coupled together. Gear shifts are made by switching from one clutch on one gearbox to another clutch on the other. The shift quality is equal to a conventional automatic, but slip, fluid drag and hydraulic losses in the system result in only slightly improved efficienc y and acceleration over the conventional planetary automatic. Developing the controlstrategy is costly too."Resent advances in conventional automatic technology have weakened the argument to develop and set up production for CVT or DCT," says Bill Martin, managing director of transmission firm Zeroshift "Some carmakers have cancelled DCT projects because of the cost."The cheapest way to build an automatic is with an AMT. AMTs use actuators to replace the clutch pedal and gear stick of a conventional manual. They keep the high efficiency and acceleration of a manual gearbox, but the shift quality on some models is lacking. Torque interruptions and the head-nod effect are the most common complaint.SO what is the alternative? There are always new ideas in transmissions, but Zeroshift says that its technology has efficiency benefits over a manual, delivering fuel economy improvements to city driving. Shift quality can also be equal to that of a refined automatic.Zeroshift's approach is an upgrade to the AMT. The synchromesh is replaced with an advanced dog engagement system.Dog engagement has been used for many years in motor sport to allow fast shifts. Conventional dog Boxes are unsuitable for road use as the large spaces between the drive lugs or 'dogs" create backlash, an uncomfortable shunt caused by the sudden change in torque direction.Zeroshift's technology solves this problem by adding a second set of drive dogs. It has also made each of The two sets of dogs only capable of transmitti ng torque in one or other opposing directions错误!未找到引用源。

变速器论文中英文资料外文翻译文献

变速器论文中英文资料外文翻译文献

变速器论文中英文资料外文翻译文献外文翻译THE RESEARCHS OFAMT SHIFTING SCHEDULESVehicular Automatic Transmission can be divided into three types: Automatic Transmission (AT), Automated Mechanical Transmission (AMT) and Continuously Variable Transmission (CVT). AMT has become a kind of transmission that is full of potentiality, due to its high transfer efficiency, low cost and easiness to manufacture.The research on AMT shifting performance is key technology in the developing. Shifting performance directly influence the market competition and industrialization of AMT.AMT has good market expectation, but during the shifting procedure, the power must be cut off which causes the poor shifting performance than AT and CVT. Only through improving the shifting performance can the commercial competence be established. So the virtual important thing is to find the way to improve shifting performance.The development of AMT can be divided into three phases: semi-automatic, automatic and intelligent. The two major part of AMT are: the hardware including the mastered object, executor, sensors and TCU; and the software performing the control strategy.The performance of AT shift influences greatly the performance of the vehicle. So the research on at shift quality is an important problem in the domain of AT researching. Shift quality control of AT is accomplished by electronic and hydraulic system. To shift smoothly, according the real time throttle valve opening and vehicle speed signal, the controller sends electronic signals to control oil pressure changing curve of the applying elements. this paper analyzes and research detailed shift quality control system,the analyzing model of shifting process and pressure changing curve of the applying elements Firstly this paper summarizes the existing evaluated quota of shift quality, and fully analyzes and introduces the existing control manner of AT shift quality.To meet the needs of research of vehicle starting and the real time control of shift, this paper puts forward a simplified model of engine-torque and a dynamics model of AT shifting process. Through the applying of the established model, this paper fully analyzes the process of the AT shifting.This paper drafts the proper oil pressure changing curve of the applying elements which can improve the AT shift quality, and gives the material calculated methods of the AG4 AT. This paper simulates the AG4 AT’s shifting process of 2H to 3H.The results of the simulation validate the established simplified models and the expected oil pressure changing curve.This paper fully analyzes the mechanism of the pressure regulating and flow controlling system of the AG4 AT, and preparatory discusses the design of the block-diagram of the shift quality control. This paper test the control system and hydraulic system of the AG4 AT by the AT hydraulic-electronic testing-bed. The result of the test validates the correction of these analyses.Automated Mechanical Transmission, as so called AMT, is a new-style transmission system. AMT technology applies the automatic technology to the manual mechanical transmission and makes the selection-gear, shift, clutch and throttle implement automatically. AMT technology is suitable for the situation of our country, and has an expansive market and development foreground. Shift schedules decide the time to shift and are the soul of the AMT. When the AMT is working, by comparing the states of the vehicle with the optimal shift schedules,the AMT decides the optimal shift time and achieves the shift automatically. This will lessen the tiredness of the driver and improve the safety. At the same time, the power and fuel-economy of the vehicle can also be improved. The author chooses the shift schedule as the key technology problem to be researched and the main study aim of this thesis is to get the optimal shift schedules for the AMT and so improve the power and fuel-economy of the vehicle. Through analyzing the influence factors of power and fuel-economy for the automobile, the author get the establishment methods for the optimal-power shift schedule and optimal fuel-economy shift schedule. In order to solve the influence of mass on the shift schedule, the author presents a variable-structure-controlled shift system. This enriches the theory of shift schedules. Because the computer simulation can save a lot of manpower and material resources comparing with the true-car test, so in this thesis, the author uses the simulation toolbox MATLAB/Simulate to setup the simulation model for shift schedules. Using this model, the optimal-power shift schedule and optimal fuel-economy shift schedule above are simulated and proved to be reasonable.Shifting performance is defined as the extent of swiftness and softness during the procedure of non-power shifting and to extend the life of the power train. The index is comfort of passenger, time duration and shock, nine factors maybe influence the shifting performance, and two experimental methods can be used to investigate the nature of this performance: one is collecting real-time data during road experiment and analyzing them, the other is the simulation of the operation conditions of the vehicle.The core of the AMT system is the control strategy, the principle of the clutch engagement, shifting procedure, the choice of control method and the CAN communication between TCU and ECU can influence the shifting performance.Shifting schedule is the schedule of auto shifting time between two shifts with controlling parameters. It includes economical and dynamical shifting schedule. At present, shifting schedule of two controlling parameters (vehicle speed and opening on throttle) is mainly used. If shifting schedule is not good,shifting will not happen at right time and the working condition of engine will be severe. It will make the sound of engine abnormally and stability badly through the whole shifting procession. Sometimes even flame out Schedule of clutch engagement is determined by releasing journey of clutch, opening of throttle, shifting, vehicle speed and loading. The mainControlling goals are engaging quantity and engaging speed. The engaging control of clutch is mainly referred to the control of engaging speed. It is divided into three stages: fast, slow, fast. Shifting quality is directly influenced by the second stage. If engaging harder, it will make shifting concussion, even flame out; if engaging more slowly, it will make the friction time longer and reduce its longevity. The main controlling parameters are difference between initiative and passive and torques on both sides. When torques being approximately equal, it is proved by experiments that it can guarantee shifting time and not make concussion through the procession of engagement at the time of difference of rotating speed below some value. Meanwhile, the abrasion of clutch is not severe.Shifting procedure is the procedure through working harmoniously among engine, clutch and transmission. Their cooperation will affect shifting time heavily. In order to decrease the shifting time, the time that is spent on the friction of the clutch should be decreased first. If we intend to increase the time of non-load stage, which helps to minimize the difference of the rotary speed between the driving disc and the driven disc. If we intend to shorten the time of the non-load stage, engage the clutch immediately after the gear change. The clutch can engage in a satisfying period if the new method of controlling the engaging speed of the clutch is realizable. And the time that is spent on synchronizing the gears should also be shortened. It can be realized in the following two ways. The first is to decrease the difference of the driving gear and the driven gear. The second is to increase the shifting force. If realizing the union control between ECU and TCU by CAN bus, AMT has the best control and the best shifting performance by use of communication strategy between TCU and ECU.Influence on shifting performance by hardwareThe elements in hardware system are the basis of proper functions of AMT. Executors, sensors, electronic components, hydraulic systems have influences on shifting performance, the choice of hardware parameters is of vital important to improvement of shifting performance.With the development of the theory and technology of vehicle, the technical increasingly mature of microprocessor and the extensive application of electronic technique on the car, people have no limit at satisfying the automotive means of transportation only, facing gradually from the request of the car power, economy and easily manipulating, flexibility, safety, an d the intelligent type of car becomes the focus in the vision of people increasingly. Company’s publicity slogan of" person, car, life"," make people the center" etc. On the side exhibit the expectation of people to the automotive individuation, humanity.In the development direction of the car intelligence, the intelligence of the automatic gearbox has important effect. But the intelligence of the automatic gearbox embodies at the establishment of the shift regulation. For the fashion, for satisfying people to the new automotive request, for competitive advantage of the car type, at present, each big factory in world worked very much in shift regulation of new car type. Among those, the most arresting is AL4 automatic gearbox developed by PEUGEOT/CITROEN and RENAULT in that there unexpectedly are the 10 kinds of so many shift regulations. In the big system of person— car — road, the good and bad of the car control, reflect primarily in the coordination of the vehicle and environment (road), the coordination of the vehicle and person. And so, the electronic automatic control system can save various regulations to provide the driver to choose to use, not only having the economic regulation, motive (call to sport the type again) regulation, but also still having the general (usual) regulation, environment temperature and regulation with the outsider condition variety etc. Namely, the point of shifting can be freely enacted for every kind of regulation. In the intelligence direction of the shift regulation, everyone has made much work up to now, parts of the results has been applied on the car. But the work that developing this intelligentshift regulation still is hard, this is mainly because of:1. The intelligence degree of the current intelligent gearbox needs to be increased, and it expresses at that accurate degree to identify environment is not high and to identify the driver’s driving can't give satisfaction.2. The intelligence function is still not perfect. The intelligent automatically shift system is an open system; it must be continuously perfect and plentiful on the current foundation. Only this way, it can adapt to the driving request of the different drivers, reducing the driver’s labor strength, increasing the performance of the whole vehicle.Conventional design method which used in the structure parameters' design of automobile gear box and synchronizer is a time-wasting job and hard work, and it is difficult to get idea design parameters and no good to the enhancement of products qualities. The optimum design of automobile gearbox and synchronizer which take the advantage of computers seeking the best structure parameters within constrains is a perfect and high-quality design method. The main target of this article is to set up a optimum mathematical model of structure parameters of the truck's gearbox and synchronizer, the auth or use a optimum method based on K-T equation to improve the design level of automobile gearbox and synchronizer. Gear box is a important part of transmission, so the optimization of automobile gearbox is very important because the transmission is a main part of automobile. According to the design request and character sofa sort of truck, the optimum mathematical model of truck's gearbox is analyzed an d set up in this article to decrease its weight and volume when the strength, stiffness, and lifetime of parts are permitted. And we can receive a satisfaction result through optimizing it's parameter for instance.Synchronizer is a important part of automobile gearbox, it make drive gear and driven gear engaged after their synchronized, so it can decrease engaged shock and noise, it can decrease shift forcing and make it comfort to gear shift and increase the life of synchronizer. The synchronized process of synchronizer is analyzed in this article; we can receive a satisfaction result through optimizing its influence parameter for instance when the synchronizedtime is the shortest. The optimum toolbox of MATLAB is a convenient of ware of modern optimization with fast speed and powerful function. The algorithms of different mathematical subsets are divided into different librarians in the form of functions in MATLAB optimum toolbox. When we use them, we just call the functions and give special parameters to solve the problems and this will be fast and accurate. The author gives an optimum design for automobile gearbox and synchronizer by using the optimum toolbox of MATLAB and receives a satisfaction result.自动变速器换档规律的研究车辆自动变速器通常分为液力机械式自动变速器(简称AT)、电控机械式自动变速器(简称AMT)和机械式无级变速器(简称CVT)。

浅谈汽车变速器外文文献翻译、中英文翻译、外文翻译

浅谈汽车变速器外文文献翻译、中英文翻译、外文翻译
In the past ten years, the transmission industry in our country has attached great importance to the development of new products, both from the input of capital and the input of manpower and material resources. Ten years ago, we developed the most transmission products have a common characteristic, is the new product development process is not complete, but with the rapid development of these years in China, China's transmission product design and development process also gradually with foreign standards. The design and development process of a complete transmission new product usually includes: L. potential customer information collection. 2 transmission market survey, determine the direction of development. 3 develop technical solutions (identify key customer needs, determine the layout, refine customer needs, set development goals, etc.). 4 feasibility analysis. 5 conceptual design (Ratio selection, road load spectrum determination, the establishment of analytical models, Package and static dynamic gap analysis, etc.).

变速器英文版文献

变速器英文版文献

Transmission (mechanics)A transmission or gearbox provides speed and torque conversions from a rotating power source to another device using gear ratios. In British English the term transmission refers to the whole drive train, including gearbox, clutch, prop shaft (for rear-wheel drive), differential and final drive shafts. The most common use is in motor vehicles, where the transmission adapts the output of the internal combustion engine to the drive wheels. Such engines need to operate at a relatively high rotational speed, which is inappropriate for starting, stopping, and slower travel. The transmission reduces the higher engine speed to the slower wheel speed, increasing torque in the process. Transmissions are also used on pedal bicycles, fixed machines, and anywhere else rotational speed and torque needs to be adapted.Often, a transmission will have multiple gear ratios (or simply "gears"), with the ability to switch between them as speed varies. This switching may be done manually (by the operator), or automatically. Directional (forward and reverse) control may also be provided. Single-ratio transmissions also exist, which simply change the speed and torque (and sometimes direction) of motor output.In motor vehicle applications, the transmission will generally be connected to the crankshaft of the engine. The output of the transmission is transmitted via driveshaft to one or more differentials, which in turn drive the wheels. While a differential may also provide gear reduction, its primary purpose is to change the direction of rotation.Conventional gear/belt transmissions are not the only mechanism for speed/torque adaptation. Alternative mechanisms include torque converters and power transformation (e.g., diesel-electric transmission, hydraulic drive system, etc.). Hybrid configurations also exist.ExplanationEarly transmissions included the right-angle drives and other gearing in windmills, horse-powered devices, and steam engines, in support of pumping, milling, and hoisting.Most modern gearboxes are used to increase torque while reducing the speed of a prime mover output shaft (e.g. a motor crankshaft). This means that the output shaft of a gearbox will rotate at slower rate than the input shaft, and this reduction in speed will produce a mechanical advantage, causing an increase in torque. A gearbox can be setup to do the opposite and provide an increase in shaft speed with a reduction of torque. Some of the simplest gearboxes merely change the physical direction in which power is transmitted.Many typical automobile transmissions include the ability to select one of several different gear ratios. In this case, most of the gear ratios (often simply called "gears") are used to slow down the output speed of the engine and increase torque. However, the highest gears may be "overdrive" types that increase the output speed.UsesGearboxes have found use in a wide variety of different—often stationary—applications, such as wind turbines.Transmissions are also used in agricultural, industrial, construction, mining and automotive equipment. In addition to ordinary transmission equipped with gears, such equipment makes extensive use of the hydrostatic drive and electrical adjustable-speed drives.SimpleThe simplest transmissions, often called gearboxes to reflect their simplicity (although complex systems are also called gearboxes in the vernacular), provide gear reduction (or, more rarely, an increase in speed), sometimes in conjunction with a right-angle change in direction of the shaft (typically in helicopters, see picture). These are often used on PTO-powered agricultural equipment, since the axial PTO shaft is at odds with the usual need for the driven shaft, which is either vertical (as withrotary mowers), or horizontally extending from one side of the implement to another (as with manure spreaders, flail mowers, and forage wagons). More complex equipment, such as silage choppers and snowblowers, have drives with outputs in more than one direction.The gearbox in a wind turbine converts the slow, high-torque rotation of the turbine into much faster rotation of the electrical generator. These are much larger and more complicated than the PTO gearboxes in farm equipment. They weigh several tons and typically contain three stages to achieve an overall gear ratio from 40:1 to over 100:1, depending on the size of the turbine. (For aerodynamic and structural reasons, larger turbines have to turn more slowly, but the generators all have to rotate at similar speeds of several thousand rpm.) The first stage of the gearbox is usually a planetary gear, for compactness, and to distribute the enormous torque of the turbine over more teeth of the low-speed shaft. Durability of these gearboxes has been a serious problem for a long time.Regardless of where they are used, these simple transmissions all share an important feature: the gear ratio cannot be changed during use. It is fixed at the time the transmission is constructed.For transmission types that overcome this issue, see Continuously Variable Transmission, also known as CVT.Multi-ratio systemsMany applications require the availability of multiple gear ratios. Often, this is to ease the starting and stopping of a mechanical system, though another important need is that of maintaining good fuel efficiency.Automotive basicsThe need for a transmission in an automobile is a consequence of the characteristics of the internal combustion engine. Engines typically operate over a range of 600 to about 7000 revolutions per minute (though this varies, and is typically less for diesel engines), while the car's wheels rotate between 0 rpm and around 1800 rpm.Furthermore, the engine provides its highest torque outputs approximately in the middle of its range, while often the greatest torque is required when the vehicle is moving from rest or traveling slowly. Therefore, a system that transforms the engine's output so that it can supply high torque at low speeds, but also operate at highway speeds with the motor still operating within its limits, is required. Transmissions perform this transformation.Many transmissions and gears used in automotive and truck applications are contained in a cast iron case, though more frequently aluminium is used for lower weight especially in cars. There are usually three shafts: a mainshaft, a countershaft, and an idler shaft.The mainshaft extends outside the case in both directions: the inputshaft towards the engine, and the output shaft towards the rear axle (on rear wheel drive cars- front wheel drives generally have the engine and transmission mounted transversely, the differential being part of the transmission assembly.) The shaft is suspended by the main bearings, and is split towards the input end. At the point of the split, a pilot bearing holds the shafts together. The gears and clutches ride on the mainshaft, the gears being free to turn relative to the mainshaft except when engaged by the clutches.Types of automobile transmissions include manual, automatic or semi-automatic transmission.ManualMain article: Manual transmissionManual transmission come in two basic types:a simple but rugged sliding-mesh or unsynchronized / non-synchronous system, where straight-cut spur gear sets are spinning freely, and must be synchronized by the operator matching engine revs to road speed, to avoid noisy and damaging "gear clash", and the now common constant-mesh gearboxes which can include non-synchronised, or synchronized / synchromesh systems, where diagonal cut helical (and sometimes double-helical) gear sets are constantly "meshed" together, and a dog clutch is used for changing gears. On synchromesh boxes, friction cones or "synchro-rings"are used in addition to the dog clutch.The former type is commonly found in many forms of racing cars, older heavy-duty trucks, and some agricultural equipment.Manual transmissions are the most common type outside North America and Australia. They are cheaper, lighter, usually give better performance, and fuel efficiency (although the latest sophisticated automatic transmissions may yield results slightly better than the ones yielded by manual transmissions). It is customary for new drivers to learn, and be tested, on a car with a manual gear change. In Malaysia, Denmark and Poland all cars used for testing (and because of that, virtually all those used for instruction as well) have a manual transmission. In Japan, the Philippines, Germany, Italy, Israel, the Netherlands, Belgium, New Zealand, Austria, Bulgaria, the UK, Ireland, Sweden, Estonia, France, Spain, Switzerland, the Australian states of Victoria and Queensland, Finland and Lithuania, a test pass using an automatic car does not entitle the driver to use a manual car on the public road; a test with a manual car is required.Manual transmissions are much more common than automatic transmissions in Asia, Africa, South America and Europe.Most manual transmissions include both synchronized and unsynchronized gearing, such as a reverse gear and a low-speed "granny gear", both of which can only be shifted into when stopped. Shifting from granny gear to a low synchronized gear is generally available while inmotion, while shifting out of reverse to any other gear typically requires the vehicle to be stopped.Non-synchronousMain article: Non-synchronous transmissionsThere are commercial applications engineered with designs taking into account that the gear shifting will be done by an experienced operator. They are a manual transmission, but are known as non-synchronized transmissions. Dependent on country of operation, many local, regional, and national laws govern the operation of these types of vehicles (see Commercial Driver's License). This class may include commercial, military, agricultural, or engineering vehicles. Some of these may use combinations of types for multi-purpose functions. An example would be a PTO, or power-take-off gear. The non-synchronous transmission type requires an understanding of gear range, torque, engine power, and multi-functional clutch and shifter functions. Also see Double-clutching, and Clutch-brake sections of the main article at non-synchronous transmissionsAutomaticMain article: Automatic transmissionEpicyclic gearing or planetary gearing as used in an automatictransmission.Most modern North American and Australian and many larger, high specification European and Japanese cars have an automatic transmission that will select an appropriate gear ratio without any operator intervention. They primarily use hydraulics to select gears, depending on pressure exerted by fluid within the transmission assembly. Rather than using a clutch to engage the transmission, a fluid flywheel, or torque converter is placed in between the engine and transmission. It is possible for the driver to control the number of gears in use or select reverse, though precise control of which gear is in use may or may not be possible.Automatic transmissions are easy to use. However, in the past, automatic transmissions of this type have had a number of problems; they were complex and expensive, sometimes had reliability problems (which sometimes caused more expenses in repair), have often been less fuel-efficient than their manual counterparts (due to "slippage" in the torque converter), and their shift time was slower than a manual making them uncompetitive for racing. With the advancement of modern automatic transmissions this has changed.Attempts to improve the fuel efficiency of automatic transmissions include the use of torque converters which lock up beyond a certain speed, or in the higher gear ratios, eliminating power loss, and overdrive gears which automatically actuate above certain speeds; in older transmissionsboth technologies could sometimes become intrusive, when conditions are such that they repeatedly cut in and out as speed and such load factors as grade or wind vary slightly. Current computerized transmissions possess very complex programming to both maximize fuel efficiency and eliminate any intrusiveness.For certain applications, the slippage inherent in automatic transmissions can be advantageous; for instance, in drag racing, the automatic transmission allows the car to be stopped with the engine at a high rpm (the "stall speed") to allow for a very quick launch when the brakes are released; in fact, a common modification is to increase the stall speed of the transmission. This is even more advantageous for turbocharged engines, where the turbocharger needs to be kept spinning at high rpm by a large flow of exhaust in order to keep the boost pressure up and eliminate the turbo lag that occurs when the engine is idling and the throttle is suddenly openedSemi-automaticMain article: Semi-automatic transmissionThe creation of computer control also allowed for a sort of cross-breed transmission where the car handles manipulation of the clutch automatically, but the driver can still select the gear manually if desired. This is sometimes called a "clutchless manual," or "automated manual"transmission. Many of these transmissions allow the driver to give full control to the computer. They are generally designed using manual transmission "internals", and when used in passenger cars, have synchromesh operated helical constant mesh gear sets.Specific type of this transmission includes: Easytronic, and Geartronic.A "dual-clutch" transmission uses two sets of internals which are alternately used, each with its own clutch, so that only the clutches are used during the actual "gearchange".Specific type of this transmission includes: Direct-Shift Gearbox.There are also sequential transmissions which use the rotation of a drum to switch gears.Bicycle gearingMain articles: Bicycle gearing, Derailleur gears, and Hub gear Bicycles usually have a system for selecting different gear ratios. There are two main types: derailleur gears and hub gears. The derailleur type is the most common, and the most visible, using sprocket gears. Typically there are several gears available on the rear sprocket assembly, attached to the rear wheel. A few more sprockets are usually added to the front assembly as well. Multiplying the number of sprocket gears in front by the number to the rear gives the number of gear ratios, often called"speeds".Hub gears use epicyclic gearing and are enclosed within the axle of the rear wheel. Because of the small space, they typically offer fewer different speeds, although at least one has reached 14 gear ratios and Fallbrook Technologies manufactures a transmission with technically infinite ratios.Causes for failure of bicycle gearing include: worn teeth, damage caused by a faulty chain, damage due to thermal expansion, broken teeth due to excessive pedaling force, interference by foreign objects, and loss of lubrication due to negligence.Uncommon typesDual clutch transmissionMain article: Dual clutch transmissionThis arrangement is also sometimes known as a direct shift gearbox or powershift gearbox. It seeks to combine the advantages of a conventional manual shift with the qualities of a modern automatic transmission by providing different clutches for odd and even speed selector gears. When changing gear, the engine torque is transferred from one gear to the other continuously, so providing gentle, smooth gear changes without either losing power or jerking the vehicle. Gear selection may be manual, automatic (depending on throttle/speed sensors), or a'sports' version combining both options.Continuously variableMain article: Continuously variable transmissionThe Continuously Variable Transmission (CVT) is a transmission in which the ratio of the rotational speeds of two shafts, as the input shaft and output shaft of a vehicle or other machine, can be varied continuously within a given range, providing an infinite number of possible ratios. The continuously variable transmission (CVT) should not be confused with the Infinitely Variable Transmission (IVT) (See below).The other mechanical transmissions described above only allow a few different gear ratios to be selected, but this type of transmission essentially has an infinite number of ratios available within a finite range. The continuously variable transmission allows the relationship between the speed of the engine and the speed of the wheels to be selected within a continuous range. This can provide even better fuel economy if the engine is constantly running at a single speed. The transmission is in theory capable of a better user experience, without the rise and fall in speed of an engine, and the jerk felt when poorly changing gears.Infinitely variableThe IVT is a specific type of CVT that has an infinite range ofinput/output ratios in addition to its infinite number of possible ratios; this qualification for the IVT implies that its range of ratios includes a zero output/input ratio that can be continuously approached from a defined 'higher' ratio. A zero output implies an infinite input, which can be continuously approached from a given finite input value with an IVT. [Note: remember that so-called 'low' gears are a reference to low ratios of output/input, which have high input/output ratios that are taken to the extreme with IVT's, resulting in a 'neutral', or non-driving 'low' gear limit.]Most (if not all) IVT's result from the combination of a CVT with an epicyclic gear system (which is also known as a planetary gear system) that facilitates the subtraction of one speed from another speed within the set of input and planetary gear rotations. This subtraction only needs to result in a continuous range of values that includes a zero output; the maximum output/input ratio can be arbitrarily chosen from infinite practical possibilities through selection of extraneous input or output gear, pulley or sprocket sizes without affecting the zero output or the continuity of the whole system. Importantly, the IVT is distinguished as being 'infinite' in its ratio of high gear to low gear within its range; high gear is infinite times higher than low gear. The IVT is always engaged, even during its zero output adjustment.The term 'infinitely variable transmission' does not imply reversedirection, disengagement, automatic operation, or any other quality except ratio selectability within a continuous range of input/output ratios from a defined minimum to an undefined, 'infinite' maximum. This means continuous range from a defined output/input to zero output/input ratio.Electric variableThe Electric Variable Transmission (EVT) is a transmission that achieves CVT action and in addition can use separate power inputs to produce one output. An EVT usually is executed in design with an epicyclic differential gear system (which is also known as a planetary gear system). The epicyclic differential gearing performs a "power-split" function, directly connecting a portion of the mechanical power directly through the transmission and splitting off a portion for subsequent conversion to electrical power via a motor/generator. Hence, the EVT is called a Power Split Transmission (PST) by some.The directly connected portion of the power travelling through the EVT is referred to as the "mechanical path". The remaining power travels down the EVT's "electrical path". That power may be recombined at the output of the transmission or stored for later, more opportune use via a second motor/generator (and energy storage device) connected to the transmission output.The pair of motor/generators forms an Electric Transmission in itsown right, but at a lower capacity, than the EVT it is contained within. Generally the Electric Transmission capacity within the EVT is a quarter to a half of the capacity of the EVT. Good reasons to use an EVT instead of an equivalently-sized Electrical transmission is that the mechanical path of the EVT is more compact and efficient than the electrical path.The EVT is the essential method for transmitting power in some hybrid vehicles, enabling an Internal Combustion Engine (ICE) to be used in conjunction with motor/generators for vehicle propulsion, and having the ability to control the portion of the mechanical power used directly for propelling the vehicle and the portion of mechanical power that is converted to electric power and recombined to drive the vehicle.The EVT and power sources are controlled to provide a balance between the power sources that increases vehicle fuel economy while providing advantageous performance when needed. The EVT may also be used to provide electrically generated power to charge large storage batteries for subsequent electric motor propulsion as needed, or to convert vehicle kinetic energy to electricity through 'regenerative braking' during deceleration. Various configurations of power generation, usage and balance can be implemented with a EVT, enabling great flexibility in propelling hybrid vehicles.The Toyota single mode hybrid and General Motor 2 Mode hybrid are production systems that use EVTs. The Toyota system is in the Prius,Highlander, and Lexus RX400h and GS450h models. The GM system is the Allison Bus hybrid powertrains and are in the Tahoe and Yukon models. The Toyota system uses one power-split epicyclic differential gearing system over all driving conditions and is sized with an electrical path rated at approximately half the capacity of the EVT. The GM system uses two different EVT ranges: one designed for lower speeds with greater mechanical advantage, and one designed for higher speeds, and the electrical path is rated at approximately a quarter of the capacity of the EVT. Other arrangements are possible and applications of EVT's are growing rapidly in number and variety.EVT's are capable of continuously modulating output/input speed ratios like mechanical CVT's, but offer the distinct difference and benefit of being able to also apportion power from two different sources to one output.HydrostaticSee also Continuously variable transmission > Hydrostatic CVTs Hydrostatic transmissions transmit all power hydraulically, using the components of hydraulic machinery. Hydrostatic transmissions do not make use of the hydrodynamic forces of the fluid flow. There is no solid coupling of the input and output. The transmission input drive is a central hydraulic pump and final drive unit(s) is/are a hydraulic motor, orhydraulic cylinder (see:swashplate. Both components can be placed physically far apart on the machine, being connected only by flexible hoses. Hydrostatic drive systems are used on excavators, lawn tractors, forklifts, winch drive systems, heavy lift equipment, agricultural machinery, etc. An arrangement for motor-vehicle transmission was probably used on the Ferguson F-1 P99 racing car in about 1961.The Human Friendly Transmission of the Honda DN-01 is hydrostatic.HydrodynamicIf the hydraulic pump and/or hydraulic motor make use of the hydrodynamic effects of the fluid flow, i.e. pressure due to a change in the fluid's momentum as it flows through vanes in a turbine. The pump and motor usually consist of rotating vanes without seals and are typically placed in close proximity. The transmission ratio can be made to vary by means of additional rotating vanes, an effect similar to varying the pitch of an airplane propeller.The torque converter in most automotive automatic transmissions is, in itself, a hydrodynamic transmission.It was possible to drive the Dynaflow transmission without shifting the mechanical gears.Hydrodynamic transmissions are used in many passenger railvehicles. In this application the advantage of smooth power delivery may outweigh the reduced efficiency caused by turbulence energy losses in the fluid.ElectricElectric transmissions convert the mechanical power of the engine(s) to electricity with electric generators and convert it back to mechanical power with electric motors. Electrical or electronic adjustable-speed drive control systems are used to control the speed and torque of the motors. If the generators are driven by turbines, such arrangements are called turbo-electric. Likewise installations powered by diesel-engines are called diesel-electric. Diesel-electric arrangements are used on many railway locomotives, ships and large mining trucks.。

汽车变速器外文文献翻译、中英文翻译、外文翻译

汽车变速器外文文献翻译、中英文翻译、外文翻译

TRANSMISSIONManual transmission is one of the most common transmission, referredto as MT. Its basic structure in a single sentence is a central axis, twoinput shaft, namely, the axial and axial oart, they constituted the transmission of the subject, and, of course, a reverse axis. Manual transmission gear transmission and manual, contain can in axial sliding gears, through different meshing gears to change gear of torsional purpose.The typical structure and principle of the manual transmission.Input shaft also says, it's in front of the spline shaft directly withclutch platen, thus the spline set by the engine relay of torque. The firstshaft gear meshing gears, often with oart as input shaft, and the gear on oart will turn. Also called shaft, because even more solid shaft of gear. The output shaft, and the second shaft position have the drive shaftgear, may at any time and under the influence of the control devices and the corresponding oart gear, thus changing the speed and torque itself. The output shaft is associated with tail spline shaft torque transmissionshaft, through to drive to gear reducer.Predictably, transmission gear drive forward path is: input shaftgear - oart gnaws gnaws gear - because the second shaft gear - corresponding corresponding gear. Pour on the axle gear can also controldevice, by moving axis in the strike, and the output shaft gear and oart gear, in the opposite direction.Most cars have five forward and reverse gear, each one has certain ratio,the majority of gear transmission more than 1, 4 gears transmission is 1, called directly, and ratio is less than 1 of article 5 gear shift accelerated called. The output axis gear in the mesh position, can acceptpower transmission.Due to the gearbox output shaft to input shaft and the speed of theirgear rotating, transform an "synchronization problem". Two rotating speeddifferent meshing gears forcibly inevitable impact and collision damage gear. Therefore, the old transmission shift to use "two feet clutch" method, ShengDang in neutral position shift to stay for a while, in the space location on the door, in order to reduce gear speed. But this operation is more complex, difficult to grasp accurately. Thereforedesigners to create "synchronizer", through the synchronizer will makethe meshing gears reach speed and smooth.Currently the synchronous transmission adopts is inertial synchronizer, it mainly consists of joints, synchronizer lock ring etc,it is characteristic of the friction effect on achieving synchronization.Mating, synchronizer and mating locking ring gear tooth circle have chamfering (locking horns), the synchronizer lock ring inside surface ofgear engagement ring and the friction surface contact. The lock horns with cone when designing the proper choice, has been made to the surface friction of meshing gears with gear synchronous, also can rapid producesa locking function, prevent the synchronous before meshing gears. When synchronous lock ring of gear engagement with surface contact surface, the outer circle in friction torque under the action of gear speed rapiddecrease (increase) or to synchronous speed equal, both locking ring spunconcurrent, relative to lock ring gear synchronous speed is zero, thus inertia moment also disappear, then in force, driven by the junction of unimpeded with synchronous lock ring gear engagement, and further to engagement with the engagement ring gear tooth and complete shift process.functional (1) change ratio, meet different driving conditions for tractionengine, the need to work in the favorable conditions and meet the speed may request. In a wide range of vehicle speed changing the size and automobile driving wheel on the size of the torque. Due to the differentdemands, automobile driving conditions of vehicle speed and torque can drive in a broad range of change. For example, in high speed can be reachedon 100km/h, while in the urban district, speed in 50km/h. In the empty flat roads, road, very little resistanceWhen When carrying carrying carrying uphill, uphill, uphill, driving driving driving resistance resistance resistance was was was great. great. great. And And And the thecharacteristics of automobile engine speed range is lesser, and torque changes more cannot meet the actual conditions range. (2) drive backward, to satisfy the need to drive car backwards. Realizing the backing, engine crankshaft are generally only to a direction,and sometimes need to back, so, often used in the transmission of reverseto realize the car drive backward.(3) in power, interruption, idle running engine starting, auto shift or need to stop the dynamic output, interrupted to transfer the power ofthe drive wheels.(4), when the clutch engagement realize gap, gearbox can not power output. For example, can ensure drivers in engine flameout loosen the clutch when leaving drivers seat.constituteBy continuously variable transmission gearbox and speed control twoparts. The main function of the variable transmission torque and speed is the change of numerical and direction, The main function of theoperation is controlled transmission mechanism, realize thetransformation of transmission ratio, shift to speed torque. Principle,Mechanical transmission main application of the principle of geartransmission velocity. Say simply, there are a number of differenttransmission gearbox group of gear pair of vehicle, and behavior, is alsoshifting gears trunk by manipulating institutions make different gearpair work. As in low-speed, ratio of gear pair work, and in high-speed, let ratio of small gear pair work.Classification,1, according to the change of transmission, transmission way, there can be divided into grade level and synthetical three.(a) : several levels of transmission ratio, can choose the fixed by gear. And can be divided into: gear axis of ordinary gear transmission and fixed gear planetary gear (part) of planetary gear transmission axisof rotation.b) stepless type transmission: ratio can be continuous variation within a certain range, commonly, mechanical and electric hydraulic typeetc.(c) comprehensive type transmission by a class type, transmission andstepless type transmission, the ratio of the maximum and minimum values can be in between the scope for several section stepless change.2, press control can be divided into compulsory manipulation, transmission, automatic control and semi-automatic control 3 kinds.(a) mandatory manipulation of transmission by direct manipulation, change gear shift lever drivers.(b) automatic control type transmission ratio of choice and change: the shift is automatic. Drivers simply manipulate accelerated pedal, transmission can according to the engine speed and load control signal signal actuator, realize the transformation of gear.(c) semi-automatic control type transmission can be divided into twokinds: one kind is part of gear, automatic shift gears, manual (mandatory)shift, Another kind is selected by button in mining under gear clutch pedalor accelerated release pedal, the executing agency to shift. Transmission of maintenance1 transmission gears maintenanceTransmission gears are always changing speed, load, gear toothsurface by bluntThe impact of load, which struck gear tooth surface (especially) damage. Common injuries are:(1) gear transmission is worn gear under normal working conditions, shows the wear uniform angled tooth gear, long wear along the directionTooth thickness shouldof the tooth should not exceed 30 percent longer,not exceed usd, Gear tooth surface area of not less than two-thirds, Running gear mesh clearance shall be commonly used, 0.15-0.26 mm to 0.8 mm limit, Gear engagement between 0.10-0.15 mm, should use limit for 0.60mm. Available batches or soft metal rivalries. If more than clearance method for measuring the pairs, should be replaced.due to fail togear clearance is mainly(2) gear teeth,broken toothmeet the requirements, gear meshing parts or work under great impact load.If you are not greater than 2mm edge of gear oil can smile ShiXiuafter-grinding continue to use, If the scope or have more than three pairs,should smile.(3) often mesh surface of the helical gear often wear face due. 10-0.30mm, in order to ensure that the axial clearance, if tooth gear good operation within the wear, can repair tank, but the amount of grinding grinding should not exceed. 50.(4) often meshing gears shaft neck, needle roller bearing and wear into seat hole hole meshing gears seat with needle bearings and shaft neckwith clearance should be 0.01 - three 0.08 mm, otherwise must be changed.2 the overhaul. Transmission shellGearbox shell is transmissions, to ensure the basis of each part of the transmission is correct position, work under load. Common injuries are:(1) the abrasion of shell bearing hole hole wear will destroy its bearing assembly relation with the bearing, the direct impact of input, output shaft transmission position relative to the hole. Bearing seat with0-0.03 mm clearance shall be used for the maximum limit, should be replacedor 0.10 mm) shell or pile hole repair.(2) shell threaded holes repair note oil ROM plug hole, dumping screwhole threads connecting bolts damage and between shellThreaded hole, can take damage with screw repair.3 transmission shaft of maintenanceTransmission in the process of operation, each bearing the torsionalmoment of change, and bending moment, JianChi part is under pressure, impact and sliding friction etc. Various axial load of common injuries are:(1) the shaft neck and neck too worn wear axis gear axis will not onlyoffset, and can bring the change gear clearance, when making noisetransmission shaft neck. Also make coordination relationship with bearingdamage, may cause ablation. So roller bearings in a place with no more than 0.02 axis wear mm needle bearing shaft neck wear with place, otherwisethan 0.07 mm landscape change or chrome.side of thein stress and more seriouswear JianChi wear(2) JianChispline. JianChi with check, when more than 0.25 or and wear with more thanusd keyway apprentice, gear engagement mm, combining with the gear with JianChi weeks, according to the mm apprentice woodruff key and shaft neckkeyways apprentice to JianChi 0.08 mm over there when the keyway weeks, or should be repaired or replaced shaft.(3) transmission shaft bending thimble resist transmission shaft withmaintenance on both ends of the roof, using pinhole batches of shaft radial micrometers, check the deviation should be less than 0.10 mm) pressure correction repair.4 synchronizer overhaulA. lock ring type inertial synchronizer ring maintenance: lock hornscone a about six degrees - 7 degrees, in use, cone Angle deformation ofrapid synchronous, and not be change in time. B. B. locking locking locking pin pin pin type type type inertial inertial inertial synchronizer: synchronizer: synchronizer: locking locking locking pin pin pin type type synchronizer major damage for cone rim wear, when, cone-disk cone rim on the thread of groove depth 0.40 mm wear to 010mm deep, should be replaced.If the cone rim are scratching, face to face, but two turning machining, must not be more than 1mm should be replaced.变速器手动变速器是最常见的变速器,简称MT MT。

车辆工程专业外文翻译--变速器

车辆工程专业外文翻译--变速器

外文原文:TransmissionsTransmissions have to compromise on either ride comfort or efficiency, but a new approach to the dog engagement gearbox could improve both.With tightening emissions regulations, carmakers are not just confining their efforts to improving combustion and after-treatment. Many are finding that modern engines are so advanced that the benefits of some engine technologies are small compared to the huge development costs involved.It's important to look at the whole vehicle in order to improve emissions. As the second most expensive piece of kit in the car, the transmission is the logical next place to look.Of all transmission technologies, the manual gearbox is the most efficient; around 96percent of the energy that is put in comes out of the other end. But not everyone can drive one or wants to. Because you have to dip the clutch pedal, it's less comfortable to drive in heavy traffic. It makes the driver tired and the torque interruptions' head-nod effect on passengers can be wearing.The driver's clutch control and corresponding torque interruptions are also the manual's weak point. When accelerating up through the gearbox, each up-shift requires the driver to cut the torque momentarily by lifting the gas pedal and dipping the clutch. It may just take a second to complete the operation, but during this time the vehicle is losing speed and acceleration.At the opposite and of the spectrum is the traditional automatic. Its shift quality is good thanks to its torque converter, but efficiency is relatively poor despite recent advances. Because of this ,a lot of the current research is trying to find an efficient alternative to the conventional automatic.The main technologies are continuously variable transmissions (CVTs); dual clutch transmissions(DCTs) and automated manual transmissions(AMTs).They all offer different benefits over the conventional planetary automatic.The CVT uses a belt chain or toroidal shaped dish drive to vary an infinite number of gear ratios. It has improved efficiency and cost when compared to conventional automatics.Its advantage comes from its simplicitu. It consists of very few components; usually a rubber or metal-link belt; a hydraulically operated driving pulley, a mechanical torque-sensing driving pulley, microprocessors and some sensors.The transmissions works by varying the distance between the faces of the two main pulleys.The pulleys have V-shaped grooves in which the connecting belt rides. One side of the pulley is fixed axially; the other side moves, actuated by hydraulics.When actuatec, the cylinder can increase or reduce the amount of space between the two sides of the pulley. This allows the belt to ride lower or higher along the walls ofthe pulley, depending on driving conditions. This changes the gear ratio. A torodial-type design works in a similar way but runs on discs and power-rollers.The "stepless" nature of its design is CVT's biggest draw for automotive engineers. Because of this, a CVT can work to keep the engine in its optimum power range, thereby increasing efficiency and mileage. A CVT can convert every point on the engine's operating curve to a corresponding point on its own operating curve.The transmission is most popular with Japanese carmakers and Japanese supplier JATCO is a major producer. But in the US and Europe driving styles are different. Uptake has been slow despite Audi and other manufacturers having offered CVT otions on their ranges.The DCT is, in effect, two manual gearboxes coupled together. Gear shifts are made by switching from one clutch on one gearbox to another clutch on the other. The shift quality is equal to a conventional automatic, but slip, fluid drag and lydraulic losses in the system result in only slightly improved efficiency and acceleration over the conventional planetary automatic. Developing the control strategy is costly too."Recent advances in conventional automatic technology have weakened the argument to develop and set up production for CVT or DCT." says Bill Martin, managing director of transmission firm zeroshift. "Some carmakers have cancelled DCT projects because of the cost."The cheapest way to build an automatic is with an AMT. AMTs use actuators to replace the clutch pedal and gear stick of a conventional manual. They keep the high efficiency and acceleration of a manual gearbox, but the shift quality on some models is lacking. Torque interruptions and the head-nod effect are the most common complaint.so what is the alternative? There are always new ideas in transmissions, but Zeroshift says that its technology has efficiency benefits over a manual, delivering fuel economy improvements to city driving. Shift quality can also be equal to that of a refined automatic.Zeroshift's approach is an upgrade to the AMT. The synchromesh is replaced with an advanced dog enqaqement system.Dog engagement has been used for many years in motor sport to allow fast shifts. Conventional dog boxes are unsuitable for road use as the large spaces between the drive lugs or "dogs" create backlash, an uncomfortable shunt caused by the sudden change in torque direction.Zeroshift's technology solves this problem by adding a second set of drive dogs. It has also made each of the two sets of dogs only capable of transmitting torque in one or other opposing directions. "By controlling the engagement and disengagement of the two sets you can shift into the new gear befor disengaging the previous gear, "says Martin. "The shift quality is smoother than a typical modern six-speed automatic luxury car."The shift is instant and the torque is not interrupted.This philosophy is used for both up and down shifts."In conventional AMT there is an emissions spike during a shift due to the need to back off and reintroduce throttle, this is eliminated by going seamless, "says Martin. "This also reduces fuel consumption."It is a relative newcomer to the transmission sector, but the firm says that it is already attracting the attention of major European and US carmakers. The big draw is as a low-cost alternative to DCT, says Martin.Because the manual gearbox architecture is largely maintained, production costs and complexity are not greater than for a conventional AMT. Development of the controls side is also considerably cheaper. Music to the ears of engineers trying to cut emissions and costs."Most of the carmakers have seen the system at least once," says Martion. "Some signed us immediately. Some have said not yet. None have said no. "That may be the clearest sign yet that when it comes to powertrain developments, carmakers are starting to focus on the transmission.HOW ZWROSHIFT WORKSThe hardware consists of two sets of bullets. mounted and actuated on two independent bullet rings. both sets of bullets run on the common hub, which is attached to the shaft with splines.Each bullet has a special profile. On one side they have an angled face for engagement. These are diagonally opposed, allowing the bullet to have a drive function for one gear and an overrun function for the other gear. The engagement faces taper backwards slightly to ensure the bullet latches onto the engaged gear under load.the opposite corners have a ramp, which pushes the bullet out of the previous gear once the new gear has been engaged.In neutral both bullet rings are positioned midway between the ratios. To select first gear, the bullets are moved into mesh with the engagement dogs.The bullets are actuated via shift forks conected to the shift actuators.The driving bullets lock first gear to the output shaft and transfer torque from the gearwheel onto the output shaft. The first gear overrun bullets are also moved into gear to lock the wheel to the output shaft in the opposite direction. This transfrs torque from the gearwheel onto the output shaft when the throttle closes and the engine overruns. This eliminates the backlash you'd expect from a dog engagement gearbox.To shift up with an open throttle, first gear's overrun bullets are unloaded and move in to engage second gear. This is followed by the previous driving ring which becomes unloaded when second gear is taken up.If the bullet is stopped from engaging fully-dog-face to dog-face-the second gear wheel opens an engagement window due to the relative speed difference. With the bullet pushed against the engagement dog compliance between the fork and actuator allows the stored energyto fire the bullet into the window.The first gear overrun bullets have now become the second gear drive bullets. As second gear takes over, the load is removed from the first gear drive bullets. These bullets are now no longer held by their retention angie and can be either moved out ofgear by actuators or pushed out of gear by contact with the ramp face of the bullet.The first gear drive bullets then move across into engagement with second gear. In second gear, the roles of the bullets are reversed.Audi RoadjetAudi plans to add comfort, luxury and practicality without increasing emissions The Roadjet concept, first shown at Detroit in January 2006,indicates a number of technical directions that Audi going to take in the coming year. The firm is focusing on interior design, powertrain, chassis, electronics and safety innovations.These new directions will help Audi strengthen its position in the sub-luxury market that it previously had to itself. Audi has two main tactics to attract new customers in the US. It is breaking into the sports utility vehicle(SUV)and compact utility vehicle(CUV)markets.It also introduces new luxury and lifestyle features to strengthen its position in the US; sales there still lag behind those of BMW, Lexus and Mercedes-Benz. The recently launched Q7 off-road luxury vehicle is a late bid to capitalise on the SUV boom.In Europe, the carmaker's technical innovations such as aluminium construction, four-wheel-drive, and novel powertrain technologies have been successful. But if Audi wants to increase its US market share, it needs to innovate in those areas valued by American customers: comfort, luxury and practicality.Audi's designers have focused on this in the interior. They have devised a new wrap-around instrument panel shape to replace the more functional design in existing models. They have expanded the vehicle's multi-media interface (MMI)control system, used for cruise control, suspension, climate and entertainment separate controls. Combined with an upgraded climate system, occupants can set their own individual climate settings.Soft, warm, earthy colours are used in the Roadjet to create a feeling of well-being. The concept uses high quality functional materials: the upholstery is fine leather; the floor is neoprene. The space between the rear seats can house a range of optional equipment: the show car featured an espresso coffee machine. Storage boxes and baby carriers are more realistic alternatives.To enhance practicality, the rear seats slide backwards and forwards diagonally to increase shoulder and leg-room or rear load space. When the rear seats are in their most forward position, an oblique-facing child seat can be used behind the seats.Roadjet's load bay features an eletrically extending load floor to ease loading, offering unmerous lashing points to secure luggage items. The sliding seats and extending load floor are very likely to enter production on Audi's Q5 and A4 models.To heighten the sense of luxury, the concept uses a costly 1,000W Bang & Olufsen sound system with 14-speakers.This incorporates a "digital voice support" function that uses microphones and the car's speakers to pick up and amplify passengers' voices to ensure clear conversation even at high speeds.In a bid to improve road safety, convenience and traffic management, carmakers are working to common standards to develop a new in-car system to talk to other cars androadside wireless olcal area networks. In traffic jams, bad weather or accident situations, cars send information to emergency services, other cars and traffic computers. The Roadjet concept featres previews such a system.The weight of all the new electronics and luxury equipment in this segment, combined with customers' growing demand for power is having a negative effect on exhaust emissions and fuel consumption. Audi is looking at sophisticated technical solutions to balance the equation.Roadjet's 3.2-litre gasoline direct injection engine is based on an existing engine but features a new fixed intake manifold with an integral vacuum reservoir to increase its output. This is combined with a two-stage cam operated variable valve lit technology to increase output.Despite the sports car performance, the Roadjet's overall fuel consumption is slightly lower than the current A4 Quattro 3.2FSI.The valve train technology, due to enter production later in 2006,lets the engine perform economically and smoothly during normal driving, switching automatically to more responsive, more powerful characteristics when the driver demands.Roadjet also has the first Audi application of speeddependent variable ratio dynamic steering for a stable highspeed motorway ride but with enhanced control on twisty country roads. Electronically-controlled variable rate dampers automatically adjust from soft and comfortable to firm and sporty to enhance safety and handling.Audi's engineers have electronically linked all of these systems to create three driver-selectable programmes: dynamic, comfort and sport. Each programme adjusts the dampers, steering, gearbox and engine eletronics to give different driving experiences.Roadjet's body styling marks a new direction for the carmaker.At 1.55m high with a wheelbase 4.7m long and 2.85m wide, the concept is roomy. The firm has used a combination of sharp feature lines and careully-sculpted concave-section doors to disguise the height. While the trademark LED tail lights are likely to enter production unchanged, steerable xenon gas discharge lights will replace the LEDs in the headlamps.Around the end of 2007 Audi will launch the Q5 CUV, based on the next A4 platform. Smaller and lighter than the Q7,it will be well placed to compete in the profitable CUV segment in the US. The Roadjet previews elements of the interior and exterior styling of this model.The Q5 will need to be more rugged to match the outdoor lifestyle image of the CUVsegment. At the same time, for the European market, the Roadjet's sharp style previews the next A4 model range, which may produce a new hatchback body in 2007 to join the conventional saloon and Avant estate. The dashboard and other new interior refinements are likely to spread across the rest of the Audi range over the next 24 months.中文译文:变速器变速箱通常不得不在舒适性和效率之间做出选择,但一种新型的“犬牙啮合式”变速箱可以同时改善这两种性能。

自动变速器英文文献加翻译

自动变速器英文文献加翻译

AUTOMATIC TRANSMISSIONThe modern automatic transmission is by far , the most complicated mechanical component in today’s automobile . It is a type of transmission that sifts itself . A fluid coupling or torque converter is used instead of a manually operated clutch to connect the transmission to the engine .There are two basic types of automatic transmission based on whether the vehicle is rear wheel drive or front wheel drive . On a rear wheel drive car , the transmission is usually mounted to the back of the engine and is located under the hump in the center of the floorboard alongside the gas pedal position . A drive shaft connects the transmission to the final drive which is located in the rear axle and is used to send power to the rear wheels . Power flow on this system is simple and straight forward going from the engine , through the torque converter , then trough the transmission and drive shaft until it reaches the final drive where it is split and sent to the two rear transmission .On a front wheel drive car , the transmission is usually combined with the final drive to form what is called a transaxle . The engine on a front wheel drive car is usually mounted sideways in the car with the transaxle tucked under it on the side of the engine facing the rear of the car . Front axles are connected directly to the transaxle and provide power to front wheels . In this example , power floes from the engine , through the torque converter to a larger chain that sends the power through a 180 degree turn to the transmission that is along side the engine . From there , the power is routed through the transmission to the final drive where it is split and sent to the two front wheels through the drive axles .There are a number of other arrangements including front drive vehicles where the engine is mounted front to back instead of sideways and there are other systems that drive all four wheels but the two systems described here are by far the most popular . A much less popular rear and is connected by a drive shaft to the torque converter which is still mounted on the engine . This system is found on the new Corvette and is used in order to balance the weight evenly between the front and rear wheels for improved performance and handling . Another rear drive system mounts everything , the engine , transmission and final drive in the rear . This rear engine arrangement is popular on the Porsche.The modern automatic transmission consists of many components and systems that designed to work together in a symphony of planetary gear sets , the hydraulic system, seals and gaskets , the torque converter , the governor and the modulator or throttle cable and computer controls that has evolved over the years into what many mechanical inclined individuals consider to be an art from . Here try to used simple , generic explanation where possible to describe these systems .1)Planetary gear setsAutomatic transmission contain many gears in various combinations . In a manual transmission , gears slide along shafts as you move the shift lever from one position to another , engaging various sizes gears as required in order to provide the correct gear ratio . In an automatic transmission , how ever , the gears are never physically moved and are always engaged to the same gears . This is accomplished through the use of planetary gear sets .The basic planetary gear set consists of a sun gear , a ring and two or more planet gears , all remaining in constant mesh . The planet gears are connected to each other through a common carrier which allows the gears to spin on shafts called “pinions” which are attached to the carrier .One example of a way that this system can be used is by connecting the ring gear to the input shaft coming from the engine , connecting the planet carrier to the output shaft , and locking the sun gear so that it can’t move . In this scenario , when we turn the ring gear , the planets will “walk”along the sun gear ( which is held stationary ) causing the planet carrier to turn the output shaft in the same direction as the input shaft but at a slower speed causing gear reduction ( similar to a car in first gear ) .If we unlock the sun gear and lock any two elements together , this will cause all three elements to turn at the same speed so that to output shaft will turn at the same rate of speed as the input shaft . This is like a car that is third or high gear . Another way we can use a planetary gear set is by locking the planet carrier from moving , then applying power to the ring gear which will cause the sun gear to turn in opposite direction giving us reverse gear .The illustration in Figure shows how the simple system described above would look in an actual transmission . The input shaft is connected to the ring gear , the output shaft is connected to the planet carrier which is also connected to a “Multi-disk” clutch pack . The sun gear is connected to drum which is also connected to the other half of the clutch pack . Surrounding the outside of the drum is a band that can be tightened around the drum when required to prevent the drum with the attached sun gear from turning .The clutch pack is used , in this instance , to lock the planet carrier with the sun gear forcing both to turn at the same speed . If both the clutch pack and the band were released , the system would be in neutral . Turning the input shaft would turn the planet gears against the sun gear , but since noting is holding the sun gear , it will just spin free and have no effect on the output shaft . To place the unit in first gear , the band is applied to hold the sun gear from moving . To shift from first to high gear , the band is released and the clutch is applied causing the output shaft to turn at thesame speed as the input shaft .Many more combinations are possible using two or more planetary sets connected in various way to provide the different forward speeds and reverse that are found in modern automatic transmission .2)Clutch packA clutch pack consists of alternating disks that fit inside a clutch drum . Half of the disks are steel and have splines that fit into groves on the inside of the drum . The other half have a friction material bonded to their surface and have splines on the inside edge that fit groves on the outer surface of the adjoining hub . There is a piston inside the drum that is activated by oil pressure at the appropriate time to squeeze the clutch pack together so that the two components become locked and turn as one .3)One-way ClutchA one-way clutch ( also known as a “sprag” clutch ) is a device that will allow a component such as ring gear to turn freely in one direction but not in the other . This effect is just like that bicycle , where the pedals will turn the wheel when pedaling forward , but will spin free when pedaling backward .A common place where a one-way clutch is used is in first gear when the shifter is in the drive position . When you begin to accelerate from a stop , the transmission starts out in first gear . But have you ever noticed what happens if you release the gas while it is still in first gear ? The vehicle continues to coast as if you were in neutral . Now , shift into Low gear instead of Drive . When you let go of the gas in this case , you will feel the engine slow you down just like a standard shift car . The reason for this is that in Drive , one-way clutch is used whereas in Low , a clutch pack or a band is used .4)Torque ConverterOn automatic transmission , the torque converter takes the place of the clutch found on standard shift vehicles . It is there to allow the engine to continue running when the vehicle comes to a stop . The principle behind a torque converter is like taking a fan that is plugged into the wall and blowing air into another fan which is unplugged . If you grab the blade on the unplugged fan , you are able to hold it from turning but as soon as you let go , it will begin to speed up until it comes close to speed of the powered fan . The difference with a torque converter is that instead of using air it used oil or transmission fluid , to be more precise .A torque converter is a lager doughnut shaped device that is mounted between the engine and the transmission . It consists of three internal elements that work together to transmit power to the transmission . The three elements of the torque converter are the pump , the Turbine , and the Stator . The pump is mounteddirectly to the torque housing which in turn is bolted directly to the engine’s crankshaft and turns at engine speed . The turbine is inside the housing and is connected directly to the input shaft of the transmission providing power to move the vehicle . The stator is mounted to a one-way clutch so that it can spin freely in one direction but not in the other . Each of the three elements has fins mounted in them to precisely direct the flow of oil through the converter .With the engine running , transmission fluid is pulled into the pump section and is pushed outward by centrifugal force until it reaches the turbine section which stars it running . The fluid continues in a circular motion back towards the center of the turbine where it enters the stator . If the turbine is moving considerably slower than the pump , the fluid will make contact with the front of the stator fins which push the stator into the one way clutch and prevent it from turning . With the stator stopped , the fluid is directed by the stator fins to re-enter the pump at a “help”angle providing a torque increase . As the speed of the turbine catches up with the pump , the fluid starts hitting the stator blades on the back-side causing the stator to turn in the same direction as the pump and turbine . As the speed increase , all three elements begin to turn at approximately the same speed . Sine the ‘80s , in order to improve fuel economy , torque converters have been equipped with a lockup clutch which locks the turbine to the pump as the vehicle reaches approximately 40-50 mph . This lockup is controlled by computer and usually won’t engage unless the transmission is in 3rd or 4th gear .5)Hydraulic SystemThe hydraulic system is a complex maze of passage and tubes that sends that sends transmission fluid and under pressure to all parts of the transmission and torque converter and . Transmission fluid serves a number of purpose including : shift control ,general lubrication and transmission cooling . Unlike the engine ,which uses oil primary for lubrication ,every aspect of a transmission ‘s function is dependant on a constant supply of fluid is send pressure . In order to keep the transmission at normal operating temperature , a portion of the fluid is send to through one of two steel tubes to a special chamber that is submerged in anti-freeze in the radiator . Fluid passing through this chamber is cooled and then returned to the transmission through the other steel tube . A typical transmission has an avenge of ten quarts of fluid between the transmission , torque converter , and cooler tank , In fact , most of the components of a transmission are constantly submerged in fluid including the clutch packs and bands . The friction surfaces on these parts are designed to operate properly only when they are submerged in oil .6)Oil PumpThe transmission oil pump ( not to confused with the pump element insidethe torque converter ) is responsible for producing all the oil pressure that is required in the transmission . The oil pump is mounted to front of the transmission case and is directly connected to a flange on the engine crankshaft , the pump will produce pressure whenever the engine is running as there is a sufficient amount of transmission fluid available . The oil enters the pump through a filter that is located at bottom of the transmission oil pan and travels up a pickup tube directly to the oil pump . The oil is then sent , under pressure to the pressure regulator , the valve body and the rest of the components , as required .7)Valve BodyThe valve body is the control center of the automatic transmission . It contains a maze of channels and passages that direct hydraulic fluid to the numerous valves which when activate the appropriate clutch pack of band servo to smoothly shift to the appropriate gear for each driving situation . Each of the many valves in the valve body has a specific purpose and is named for that function . For example the 2-3 shift valve activates the 2nd gear up-shift or the 3-2 shift timing valve which determines when a downshift should occur .The most important valve and the one that you have direct control over is the manual valve. The manual valve is directly connected to the gear shift handle and covers and uncovers various passages depending on what position the gear shift is paced in . When you place the gear shift in Drive , for instance , the manual valve directs fluid to the clutch pack ( s ) that activates 1st gear . It also sets up to monitor vehicle speed and throttle position so that it can determine the optimal time and the force for the 1-2 shift . On computer controlled transmission , you will also have electrical solenoids that are mounted in the valve body to direct fluid to the appropriate clutch packs or bands under computer control to more precisely control shift points .8)Seals and GasketsAn automatic transmission has many seals and gaskets to control the flow of hydraulic fluid and to keep it from leaking out . There are two main external seals : the front seal and the rear seal . The front seal seals the point where the torque converter mounts to the transmission case . This seal allows fluid to freely move from the converter to the transmission but keeps the fluid from leaking out . The rear seal keeps fluid from leaking past the output shaft .A seal is usually made of rubber ( similar to the rubber in a windshield wiper blade ) and is used to keep oil from leaking past a moving part such as a spinning shaft . In some cases , the rubber is assisted by a spring that holds he rubber in close contact with the spinning shaft .A gasket is a type of seal used to seal two stationary parts that are fastedtogether . Some common gasket materials are : paper , cork , rubber , silicone and soft metal .Aside from the main seals , there are also a number of other seals and gasket that vary from transmission to transmission . A common example is the rubber O-ring that seals the shaft for the shift control lever . This is the shaft that you move when you manipulate the gear shifter . Another example that is common to most transmission is the oil pan gasket . In fact , seals are required anywhere that a device needs to pass through the transmission case with each one being a potential source for leaks .9)Computer ControlsThe computer uses sensors on the engine and transmission to detect such things as throttle position , vehicle speed , engine speed , engine load , stop light switch position , etc . to control exact shift points as well as how soft or firm the shift should be . Some computerized transmission even learn your driving style and constantly adapt to it so that every shift is timed precisely when you would need it .Because of computer controls , sports models are coming out with the ability to take manual control of the transmission as through it were a stick shift lever through a special gate , then tapping it in one direction or the other in order to up-shift at will . The computer monitors this activity to make sure that the driver dose not select a gear that could over speed the engine and damage it .Another advantage to these “ smart” transmission is that they have a self diagnostic mode which can detect a problem early on and warn you with an indicator light on the dash . A technician can then plug test equipment in and retrieve a list of trouble codes that will help pinpoint where the problem is .自动变速器对于现代的汽车,自动变速器是一个复杂的组件,这种传递动力的方式,是液力变矩期充当离合器来连接发动机和变速器。

汽车手动变速器外文文献翻译、中英文翻译、外文翻译

汽车手动变速器外文文献翻译、中英文翻译、外文翻译

附录外文文献Manual transmission is the most basic of transmission of a type, its effect is changing, and provide the transmission reverse and neutral. Usually, the pilot on the clutch pedal through manipulation and in any HuanDangGan can choose between gear. There are a few manual transmission, such as motorcycles, cars, some transmission shift transmission allows only sequence, the transmission is called sequence shift transmission. In recent years, along with the electronic control components durability, computerized automatic switching clutch automatic shift of transmission in Europe since the start line are more and more popular, car Volkswagen and ford are sold in the city on the double clutch provide updated generation, transmission from the start with two clutches, every shift automatically switch to another group of clutch engagement, need not as quick as traditional in manual have only one group separated again clutch engagement, shifting speed is faster, more small change gear vibration.Internal structure: shaftDecorate a form of transmission shaft type usually have two and three shaft type two kinds. Usually a rear wheel drive car will adopt three axis type, i.e. input shaft transmission, the output shaft and oart. Input shaft front associated with engine, borrow clutch output shaft back-end through the flange and universal transmission device connected.Input shaft and the output shaft in the same horizontal line, with their oart parallel arrangement. From the input shaft power through the gears to preach to the output shaft oart again. In many input and output shaft transmission shaft could engage in together, so to power, then the gear oart called directly. Direct files through uniaxial transmission, the ratio of 1:1, the highest transmission efficiency. Even in the transmission directly, cannot offer the input shaft, and the output shaft is decorated in a straight line to reduce work needed to inherit the torque transmission.Reversing deviceGenerally speaking, the reverse gear reducer than can alsosynchronizerIn synchronized meshing gears have type synchronizer Settings, can make two gear engagement in the first, before the speed reached synchronizer in all of this manual gear transmission of the car has been usedClutch,The clutch is can make two gear with a separate with mechanical parts, two gear transmission power can be combined, but when to speed, so will depend on the first two gear clutch, change gear ratio, the two gear transmission power, continue again Control:GearIn simple terms, the high speed, low speed ShengDang when the time cameEvery car high speedCompared with automatic transmissionThis refers to the automatic transmission of traditional hydraulic transmission, namely through hydraulic torque converter and planetary gear transmission power automatic transmission.Advantages: transmission efficiency than automatic gearboxes for high, of course, theoretically can compare economical.maintenance will be cheaper than transmission.If you want to higher cost, can begin from both the row of convenience and high power附录外文文献的中文翻译手动变速器是汽车变速器中最基本的一种类型,其作用是改变传动比,并提供倒档和空档。

变速器外文翻译

变速器外文翻译

The ZF AS Tronic Family Automotive Transmissions forAll Commercial Vehicle Classes1 Requirements for Commercial Vehicle TransmissionsCustomers demand high efficiency along with increasing vehicle comfort and safety. As an independent transmission manufacturer, ZF customer needs include the needs of drivers, forwarding companies, and vehicle manufacturers.Therefore, ZF considers the many requirements that a new transmission concept must fulfill when developing a transmission, Figure 1 .图1商用车辆的需求Fig. 1 Requirements for commercial vehiclesKeeping and later during operation. That is why fuel consumption is increasingly one of the decisive vehicle features that separate the competition. A modern transmission can make an important contribution here: On the one hand by improving efficiency and on the other hand in automatic transmissions by the optimal selection of the gear ratio dependent on the driving situation. Reducing the transmission, s weight also leads to reduced costs: Using less material reduces acquisition costs and enabling a higher payload reduces operating costs. On the one hand, decreased oil consumption contributes to environmental protection; additionally, it has an immediate influence on the costs, however, th at accrue throughout the vehicle ’ s service life.The demand for system comfort increasingly approaches the standard set by car technology, whereas in this case limits are set by mass ratios and cost constraints.Low noise emissions are a result of legal regulations on the one hand but also contribute to more comfortable driver workplaces when met. Furthermore, electronic systems increasingly support the driver and relieve him/her from routine tasks. This benefits safety in traffic.2 Advances with Automatic TransmissionsAutomatic transmissions can satisfy many of the demands that customers make on commercial vehicles considerably better than manual transmissions. Despite the fact that automatic transmissions are generally more expensive, if one takes the complete installed manual transmission system including the gearshift system into account, the difference in acquisition costs is no longer as great. Moreover, the goal of future developments is to further reduce the costs for automatic transmissions.Even today the higher acquisition costs are already paying for themselves relatively quickly due to lower operating costs so that automatic transmissions are economically advantageous in the long run. The efficiency of the AS Tronic family of transmissions is comparable to a manual transition; however, as a rule, the shifting point selection is better due to the application of an automatic driving strategy, which positively affects fuel consumption. A long term study conducted by ZF and DEKRA found that the automatic shifting point selection represents the consumption performance of a very good, concentrated driver. Thus, averaging all drivers and driving situations in a commercial fleet, consumption is reduced on the order of 3 percent since the engine operates reliably in the optimum speed range with regard to fuel consumption; a process that is controlled independently of the driver, s qualification.An additional advantage in terms of operating costs is reduced clutch wear. Reduced differential speeds during starting and shifting operations lengthen the service life of the clutch, which has al so been proven in long term tests. Many vehicle manufacturers take this into account and offer a significantly longer warranty cover on the clutch in AS Tronic transmissions.By automating the clutch, the clutch pedal is no longer needed, which clearly simplifies operation for the driver, particularly in stop and go traffic or when maneuvering. The automatic gear selection relieves the driver from shifting as well, whereby he/she can concentrate better on road traffic. However, at the same time, the driver can engage manually at any time, for instance in driving situations where thedriver's forward field of vision is in question. This takes place according to Shift by Wire via an electromechanical control switch so that only very little actuating forces are applied when manually selecting gears. The rapid automatic shifting and the protection against operating error also contribute to the increase in driver comfort while at the same time protecting the transmission and driveline. In addition, the absence of a mechanical link between shift lever and transmission reduces cabin noise.Using an automatic transmission also has advantages for vehicle manufacturers. Like the clutch control, the complete shift linkage is no longer needed, which makes both left and right hand steering vehicles easy to manufacture. When designing the driver workplace, anything is possible in terms of operating the transmission.3 The ZF AS Tronic FamilyZF began developing automated manual transmissions for commercial vehicles early. The first product was a partially automated transmission with automatic pre selection, which was introduced into the market in 1984. Ten years later, an automated transmission followed with the introduction of the first AS Tronic; however, the driver still had to select gears. Its successor model was first equipped with an intelligent shift program, which has been in production since 1998. Thus, a fully automatic solution was offered in a heavy commercial vehicle for the first time.The chosen transmission concept for AS Tronic resulted in the most efficient solution possible for larger volumes. Extensive integration and removal of unnecessary components opened up potential cost savings. As a group drive, AS Tronic is designed with an unsynchronized basic transmission and synchronized splitter and range change group, Figure 2.图2 ZF AS Tronic的3D剖示图Fig. 2 ZF AS Tronic: 3D section cutIn order to reduce the weight of the transmission, a design with two countershafts was chosen, which is optimal in this performance class in terms of weight. Due to a modular design and a basic transmission with 3 or 4 speeds, l6 peed, 12 speed, and 10 speed variants could be represented.In the basic transmission, the synchronizations were replaced with shift dogs, because the synchronization can take place by controlling the internal combustion engine in modern EDC engines. An additional transmission brake is then required for up shifts, which is located on one of the two counter shafts. A standard dry clutch is used. It is fully automatic so that a clutch pedal is no longer necessary. All automated components are pneumatically operated and are combined within modules that are integrated into the transmission housing. The coordinated operation of transmission, clutch, and engine takes place by electronic control, which is located in the shift module. The interfaces to the out side were minimized.AS Tronic was initially limited to torques of 2, 300 Nm (12 speed) and 2, 600 Nm (16 speed). Afterward, variants were introduced in a two step development, which expand the torque ranges of 12 speed transmissions upwards. AS Tronic is offered in direct drive and overdrive designs and is generally available with an integrated secondary retarder “Intarder. ’’Automatic transmissions have found increasing acceptance in heavy commercial vehicles in the past few years and enjoy enormous popularity among customers. However, the advantages of these transmissions are also demonstrated especially in light and medium duty commercial vehicles. Vehicles in these classes are primarily used in city and regional traffic. Relief from operating the transmission and the clutch is especially important in this case because the traffic environment requires the driv er’s full attention. Furthermore, this sector is marked by a high number of untrained drivers and frequent driver turnover. Therefore, reducing the driver's influence on fuel consumption and clutch wear is an unmistakable advantage, not to mention safeguarding against transmission and clutch damage caused by the driver.For these reasons ZF decided to expand the product portfolio for automatic transmissions systematically into the area of low torques, Figure 3.图3变速器型谱:ZF AS Tronic的转矩范围Fig. 3 Transmission portfolio:the ZF AS Tronicproducts with torque rangesStarting from the technical fundamental principle- two pedal solutions with automatic shifting and a customer benefit that is commensurate with the AS Tronic- smaller AS Tronic transmission will be developed as well. They receive additional coding to their genuine designation in order to mark their association to the respective vehicle applications. AS Tronic mid will be used for applications from 800 Nm to 1, 600 Nm;AS Tronic lite will cover trucks in the lower torque range up to 1, 050 Nm with 6 speed transmissions.4 ZF AS Tronic midThe vehicle sector where the AS Tronic mid series will be used is very sensitive to price and highly differentiated in terms of application types. Thus, midrange vehicles will service both distributor and long distance transport as well as construction sites. Therefore, one of the focal points of development lies in a cost effective design that will fulfill the many and diverse customer requirements easily and also cover the wide torque range.Consistent product planning led to the development of an uncompromising midrange transmission series designed for automation. It encompasses seven transmission types combined into one modular design. With 840 mm short and 900mm long transmission variants, the modular design concept is primarily based on the variation of the wheel widths in order to cover the torque ranges up to 1, 200 Nm and 1,600 Nm respectively. Both transmission lengths will be offered in direct and overdrive de signs. Compared to the AS Tronic, the AS Tronic mid transmissions are approx. 50 to 65 kg lighter. In order to optimize costs, a consistent complexity management system was pursued. Approximately 40% of the components were taken from existing transmissions in production at ZF.In order to offer uniform automation technology for all commercial vehicles in the midrange and heavy duty sectors, the proven AS Tronic components such as transmission/clutch actuators, electronics, and software were used. Due to the inter face equality this achieved, the vehicle manufacturer can offer both AS Tronic and AS Tronic mid series in almost identical vehicles with various drive line variants at minimal expense.In a preliminary concept study, various gear set concepts were considered. Eight gear set formulas were compared using eleven selected evaluation criteria in terms of function, costs, and deadline. In order to provide this complex decision matrix with the necessary transparency, a decision making software tool was used. The choice was made for a 12 speed gear set (2x3x2), which is comparable to a conventional 9 speed gear set in terms of design space and weight and even has advantages compared to a 10 speed gear set, Figure 4.图4 ZF AS Tronic mid变速器剖示图Fig. 4 ZF AS Tronic mid in complete viewIt consists of engaging and disengaging input constants ( splitter group), 3 speed main transmission, and an output end planetary drive stage (range change group). Synchronizations are used in the splitter and range change group; the main transmission shifting elements are designed as dogs. The gear steps has a slightly progressive gear interval due to a small increase in the gear ratio. Thus, at a total gear spread of approx. 12. 8, the gear ratio of 23. 8 % from 11th to 12th speed is on par with a comparable 16 speed transmission. For the first time, the gear ratio of the reverse gear was designed 13. 1, i. e. slower than 1st gear on a range change group transmission by an offset engagement over the reverse idler gear. In close cooperation with the customers, high drivability was already emphasized in the specification phase. Upon completion of the rough design, the drivability release criteria of one customer were already proven in simulations.A detailed cost analysis of the gear units in ZF transmissions led to the design of the planetary rear mounted range change group in the AS Tronic mid,in which the most cost effective solutions were adopted in each case. Thus, the design of the new gear unit is marked by the synchronization of the AS Tronic and the gear set design of the Ecosplit Figure 5.图5 ZF AS Tronic mid:行星齿轮传动Fig. 5 ZF AS Tronic mid:planetary drive detailThe bearings of the swing fork in the range change group are realized between the twohousing parts, which minimizes seal points to the outside and possible corrosion weak points. The clutch actuating cylinder was turned in driving direction from the 6 o’ clock position for AS Tronic to the 8 o'clock position for AS Tronic mid. This not only increases vehicle road clearance and brings the actuating cylinder out of the danger zone, it al so offers the flexibility to react to potential requirements pushed clutch release under compression.Different from the AS Tronic, the AS Tronic mid gear set will only be designed with one counter shaft. The solution was the best in a parameter study for the torque range considered, which takes into account both the modular design aspects as regards optimal gear set length variation as well as the legally permitted noise requirements. As a result, the developer faced an additional challenge. If the oil pump and transmission brake are each driven by one countershaft in the AS Tronic, then both components now must be combined in a joint, cost effective brake pump module.Maximizing transmission efficiency in order to reduce fuel consumption attracted much interest during development. By consistently changing splash lubrication to injection lubrication, quasi dry sump lubrication was achieved so that diving losses do not occur. In order to optimize the lubrication system, oil flow calculations were conducted. The oil itself was handled like a structural/ design element. ZF has worked intensively for years with lubricant manufacturers in order to develop synthetic oils such as the ZF Ecofluid M, which is used in these transmissions. This oil has low viscosity and therefore contributes low internal losses; however, at the same time it offers sufficient lubricating film to guarantee the service life of gears, bearings, and synchronizations. An additional advantage of Ecofluid M is high stability, which makes clearly longer oil change intervals possible and greatly reduces oil consumption.Shift dogs in the main transmission and a com pact transmission design with small center distance also contribute to loss reduction. All these measures together increased the efficiency in the direct gear from 99. 2 to 99. 6% under comparable operating conditions. Active heat management enabled additional fuel savings. If the transmission runs at approx. 60℃ oil sump temperature on road, the oil viscosity can be further reduced by additionally heating to 80℃. In this case, AS Tronic mid is optionally available for the addition of a highly integrated heat exchanger. Short payback periods of approx, one year are ensured by cost effectively integrating theheat exchanger cartridge with the integrated bypass valve in the oil circulation on the intake side.ZF AS Tronic系列-适用于各种商用车辆的自动变速器1 商用车辆变速器的需求客户的要求是在提高车辆舒适性和安全性的同时也提高效率。

变速器外文文献翻译、中英文翻译、外文翻译

变速器外文文献翻译、中英文翻译、外文翻译

TRANSMISSIONEngine output speed is very high, the power and the maximum torque in certain areas of the speed. In order to exert the engine, you must have the best performance, to coordinate the speed of the engine and the actual speeds. Transmission in automobile driving process between the engine and wheels, in different ratios, through the shift in the engine can work under the condition of the best performance. The development trend of the transmission is more complex, more and more is also high automation degree, automatic transmission is the mainstream of the future.Car engines in certain speed can reach the best state, the output power of the bigger, fuel economy and better. Therefore, we hope in the best condition engine always work. But, in the use of the car to have different speed, the contradictions. This contradiction through the transmission to solve.Auto transmission function in a single sentence, is called the speed change, which reduced growth slowing or thickening twist. Why can increase twist, and slowing growth and to reduce twist? Put the power output unchanged, the engine power can be expressed as N = wT, w is turning, T is the angular torque. When N fixed, w and T is inversely proportional to the. So the growth will be reduced, slow increase twist. Auto transmission gear transmission is based on the principle of variable twist, each corresponding to different into gear transmission, in order to adapt to the different operating conditions.General manual transmission shaft set the input and output shaft, and say, another three axis reverse axis. Three main transmission shaft type is the speed of the input shaft structure, the speed of the engine, is also the output shaft speed is presented. By output shaft gear generated between different speeds. The gear is different with different ratio, also have different speed. Such as Zhen Zhou Nissan ZN6481W2G type SUV driver’s dynamic transmission, it is respectively: 1 ratio of 1:3.704 gears, 2.202 2:1, 3:1; 1.414 4 gears, - 5 (1): overdrive dependent.When the car started when the driver choose 1 files, dial 1 1/2 shift fork synchronizer backward joints and 1 shift gear lock on the output shaft, and the power input shaft, and the output shaft shift gears, 1 shift gear drive output shaft, output shaft will power to transmission (red arrows). The typical one shift gear ratio is 3:1, i.e. input shaft turn 3 laps, output shaft turn 1 lap.When the car growth drivers choose 2 files, dial 1 1/2 shift fork synchronizer and 1 separateness from 2 after mating locking output shaft gear and power transmission line, which is similar to the output shaft gear with 2, 1 files output shaft gear. The typical 2 shift gear ratio is 2.2:1, input, output shaft turning 2.2 pivot, 1-1 RPMincreases, torque shift.When gas growth drivers choose 3, dial 1 1/2 shift fork to synchronizer, and back to space three/four file synchronizer will move until 3 gear lock in the output shaft, make the power from the first shaft -- -- on the output shaft transmission gears, 3 through the output shaft gear shifting speed. The typical 3 ratio was 1.7:1, the input shaft turning circle, the output shaft 1.7 turn 1 ring, is further growth.When gas growth drivers choose 4 gears, fork will 3/4 file synchronizer from 3 gear directly with the input shaft driving gear engagement, power transmission directly from the input shaft to the output shaft, and the output shaft is 1:1 ratio and the input shaft speed. Due to the force, and the direct oart shift, the gear transmission efficiency ratio. Cars run most time in order to achieve the best directly file fuel economy.Shift to go into space, transmission in the transmission gears have locked in the output shaft, they cannot drive the output shaft rotation, no power output.General car manual transmission ratio main points above 1-4, usually designers to first identify the lowest (1) and (4) transmission, the ratio between after general distribution according to form. In addition, there is a reverse and overdrive, overdrive called 5 files.When the car to accelerate whether isolated car drivers choose more than 5, 5 gear transmission is typical 0.87:1, namely with big gear drive pinion gear turns, when active 0.87 lap, passive gear has turned over one lap.When the reverse in the opposite direction to the output shaft rotation. If a gear when reverse rotation, plus a gear will become a positive spin. Using this principle, will add a reverse gear do "medium", the direction of rotation axis, so has reversed a reverse axis. Reverse transmission shaft independent in housing, and parallel axis, when oart in gear and gear and oart output shaft gear, output shaft to will instead.Usually the reverse synchronizer is controlled by the jointing, so May 5 files and reverse position is in the same side. Due to the middle, reverse gear transmission is generally greater than 1 gear transmission ratio, twist, some cars met with forward instead of steep open up in reverse.From driving gear transmission is smooth; more is better, more adjacent gear shift between the transmission ratio, shift easy and smooth. But the gear transmission fault is more complex structure, big volume and light auto transmission is now commonly 4-5. At the same time, the transmission ratio is not an integer, but with the decimal point, this is not the whole number of meshing gears, two gear ratio is the euploid number will lead to two gear surface non-uniform wear, tooth surface quality of differences.Manual transmission and synchronizerManual transmission is one of the most common transmissions, referred to as MT. Its basic structure in a single sentence is a central axis, two input shaft, namely, the axial and axial oart, they constituted the transmission of the subject, and, of course, a reverse axis. Manual transmission gear transmission and manual, contain can in axial sliding gears, through different meshing gears to change gear of torsional purpose. The typical structure and principle of the manual transmission.Input shaft also says, it's in front of the spline shaft directly with clutch platen, thus the spline set by the engine relay of torque. The first shaft gear meshing gears, often with oart as input shaft, and the gear on oart will turn. Also called shaft, because even more solid shaft of gear. The output shaft, and the second shaft position have the drive shaft gear, may at any time and under the influence of the control devices and the corresponding oart gear, thus changing the speed and torque itself. The output shaft is associated with tail spline shaft torque transmission shaft, through to drive to gear reducer.Predictably, transmission gear drive forward path is: input shaft gear - oart gnaws gear - because the second shaft gear - corresponding gear. Pour on the axle gear can also control device, by moving axis in the strike, and the output shaft gear and oart gear, in the opposite direction.Most cars have five forward and reverse gear, each one has certain ratio, the majority of gear transmission more than 1, 4 gears transmission is 1, called directly, and ratio is less than 1 of article 5 gear shift accelerated called. The output axis gear in the mesh position, can accept power transmission.Due to the gearbox output shaft to input shaft and the speed of their gear rotating, transform a "synchronization problem". Two rotating speed different meshing gears forcibly inevitable impact and collision damage gear. Therefore, the old transmission shift to use "two feet on-off" method, accelerate in neutral position shift to stay for a while, in the space location on the door, in order to reduce gear speed. But this operation is more complex, difficult to grasp accurately. Therefore designers to create "synchronizer", through the synchronizer will make the meshing gears reach speed and smooth.Currently the synchronous transmission adopts is inertial synchronizer, it mainly consists of joints, synchronizer lock ring etc, it is characteristic of the friction effect on achieving synchronization. Mating, synchronizer and mating locking ring gear tooth circle have chamfering (locking horns), the synchronizer lock ring inside surface of gear engagement ring and the friction surface contact. The lock horns with cone when designing the proper choice, has been made to the surface friction of meshinggears with gear synchronous, also can rapid produces a locking function, prevent the synchronous before meshing gears. When synchronous lock ring of gear engagement with surface contact surface, the outer circle in friction torque under the action of gear speed rapid decrease (increase) or to synchronous speed equal, both locking ring spun concurrent, relative to lock ring gear synchronous speed is zero, thus inertia moment also disappear, then in force, driven by the junction of unimpeded with synchronous lock ring gear engagement, and further to engagement with the engagement ring gear tooth and complete shift process变速器发动机的输出转速非常高,最大功率及最大扭矩在一定的转速区出现。

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In recent years, the automotive automatic transmission there are three main types: mechanical electronic control automatic transmission (AMT), Stepless automatic transmission (CVT) automatic transmission and hydraulic machinery (AT). In the electronically controlled automatic transmission in the field of mechanical, in recent years, there is a newvariable-speed transmission, that is, double-clutch automatic transmission speed (Dual Clutch Transmission), due to both inherited and the AMT structure manual transmission easy to install Compact space, light weight, high-efficiency drive, many of the advantages of low manufacturing costs, and the integration of AT under the uninterrupted power, the rapid shift of the good characteristics of a smooth, quickly became the industry's R & DCT will be the new hot spot for a certain On the degree of change to the existing transmission market. In the next few years, the global transmission of light vehicle market will be AT, CVT, and between the DCT.
Dual-clutch transmission technology development and application of the history of the status quo:
Dual-clutch transmission (DCT) to the concept of the 1960s are now history. As early as1939 inGermanyto apply for the Kegresse.A first dual-clutch gearbox of the patent, a manual transmission will be divided into two parts, the design concept, part of the odd file transfer, even another part of the file transfer. And the transmission of power through the linking of the two clutch two input shaft, adjacent to the file of passive gear and the two staggered mesh gear input shaft, with two clutch control can be achieved without cutting off power conversion of the transmission ratio, thus shortening the Shift time, effectively enhance the quality of transmission,
Dual-clutch transmission characteristics of the structure and working process
The transmission has been carried out in the cargo on board the pilot, was limited to the control of technology, such transmission has not deployed mass production. Then in the 1980s, Porsche is also dedicated to the invention of the car's dual-clutch gearbox (PDK), but it will not DCT technology into mass production.
外文资料翻译
学生姓名:指导教师:朱天军
河北工程大学机电学院
2011年6月
Dual-clutch transmission technology highlights
Transmission technology motor vehicles as a whole is shifting from manual to automatic transmission development, especially at this stage of rapid development of computer technology used in variable-speed transmission system, so that the car automatic transmission technology has been rapid development.
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