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1、機(jī)械專業(yè)中英文文獻(xiàn)翻譯 英文原文 Stepless speed technology Stepless speed technology USES belt and the work of the Lord diameters driven pulley, cooperated with the power to deliver, can realize the TRANSMISSION ratio of the continuous change, and get the TRANSMISSION and engine condition the best match between.

2、 Common step-less transmission have hydraulic mechanical step-less transmission and belt type step-less transmission , the current domestic market of the vehicles already more and more. Editor this section step-less transmission and the origin of the automatic transmission Automatic transmission is

3、 easy to operate, reduce fatigue driving, born of the gear drive system, the control method, it can be divided into the hydraulic controlled hydraulic and electric automatic transmission hydraulic automatic transmission; According to the change of the transmission way and can be divided into have le

4、vels of automatic transmission and no levels of automatic transmission. Therefore, step-less transmission is actually a kind of automatic transmission, but it than common automatic transmission is much more complex, more advanced technologies. Step-less transmission and common hydraulic automatic tr

5、ansmission of the biggest differences is on the structure, the latter is by hydraulic control gear drive system structure, still have the gears, it can be realized in between the two block is continuously variable transmission , and is two groups plate and a belt speed of than traditional automatic

6、transmission, simple structure, smaller. In addition, it is free to change gear ratios, so as to realize the full speed stepless speed change, make more smoothly, without the traditional transmission shift at the "" feeling. Editor this section step-less transmission classification To realize stepl

7、ess speed, driving mode can be adopted according to the liquid transmission, power transmission and mechanical drive three ways. Liquid transmission Liquid transmission is divided into two kinds: one kind is hydraulic, mainly is composed by the pump and motor or the valve and pump variable speed o

8、f transmission device, apply to small and medium-sized power transmission. Another kind is hydraulic type, adopts hydraulic coupler or hydraulic torque of variable speed drive, used in high power (kw). To hundreds of thousands of The main characteristics of liquid transmission is: speed range, can a

9、bsorb the impact and big to prevent transmission efficiency high, overload, long life, easy to realize automation: manufacturing precision demand is high, the price is more expensive, output characteristics for constant torque, sliding rate is bigger, running vulnerable to leak. Power transmission

10、 Power transmission basically is divided into three categories: one kind is electromagnetic sliding type, it is in the asynchronous motor installed in electromagnetic clutch, sliding by changing its exciter current to speed, this belongs to a kind of relatively backward speed adjustment way. The cha

11、racteristics of simple structure, low cost, convenient operation and maintenance, sliding, low efficiency, biggest fever, not suitable for long-term serious load operation, the general used only for small power transmission. Second is the dc motor type, changes in the magnetic flux or change the arm

12、ature voltage realize the speed. Its characteristic is speed range, high precision, large and complex, high cost but equipment, maintenance difficulties, are used for medium power range (dozens to hundreds of kw), has gradually been ac motor type instead. Three kinds of ac motor type is, through the

13、 change pole, pressure control and frequency conversion for the speed. The most practical application for variable frequency speed regulation, namely deserve using a horns, and then get luffing power drive motor variable speed. Its characteristic is the speed performance is good, range, high efficie

14、ncy, it can automatic control, small volume, it is suitable for a wide range of power: mechanical properties in single reducing speed constant torque, low efficiency and low speed running smooth enough, the price is higher, maintenance should be professional. In recent years, frequency converter as

15、an advanced, excellent variable speed device rapid development of machinery, step-less transmission produced a certain impact. Mechanical transmission The main characteristic of the mechanical transmission is stable, rotate speed sliding rate, reliable, and has small constant power mechanical prop

16、erties, the transmission efficiency is high, and simple structure, convenient maintenance, the price is relatively cheap; But parts processing and lubrication to demand higher bearing capacity, low resistance, resistance to impact overload and poor, so general suitable for medium and small power tra

17、nsmission. 1, MT The manual transmission (MT: Manual Transmission) gearset, because the number of teeth of each gear is fixed, each gear ratio is a fixed value (that is, the so-called "level"). For example, a block ratio of 3.455, the second gear is 2.056 to the five-speed 0.85, these figures are

18、multiplied by the main reduction ratio is the total transmission ratio of the power train, 5-speed transmission 5 value (ie 5 level), so it is a step-variable transmission. The manual transmission is the most common transmission, composed of relatively AT and CVT, its structure is simple, the main a

19、xis of the input shaft, output shaft and the intermediate shaft, the shaft bearings, each gear, the synchronizer, the shift operating mechanism. Manual transmission failure rate is relatively low, the use of lower cost. 2, AT Automatic transmission (AT: Automatic Transmission) automatic upshifts

20、and downshifts lifting gear control, computer based primarily on speed and load (throttle pedal stroke), but also refer to a variety of signal transmission oil temperature, shift mode. The same point of the AT and MT both step-variable transmission, only that the AT has a continuous speed ratio vari

21、ation in the respective gear, and the speed according to the vehicle speed automatically to achieve a gear change for hand can be eliminated block cars "frustrated" variable block feeling. (1) AT structure: Compared with manual wave, hydraulic automatic transmission (AT) are very different in struct

22、ure and use. Manually waves mainly composed of gears and shafts, variable speed torque generated by different gear combinations; AT by the torque converter, a planetary gear and the hydraulic steering system, to achieve a variable speed hydraulic transmission and gear combination moment. Wherein the

23、 torque converter is the most characteristic parts of the AT, it is composed by the pump impeller, turbine and guide wheel member, directly enter the engine power transmitting torque and clutch effect. (2) AT advantages and disadvantages: AT without a clutch shift, gear changes less stable connectio

24、n, so the operation is easy, both to car, bring comfort to the car. But the disadvantage is also one of the speed changes in response to slow, there is no manual transmission is sensitive, so many play car owners like to open a manual transmission car; Second, the economic cost of oil, the transmiss

25、ion efficiency is low variable torque range is limited, in recent years, the introduction of electronic control technology improve this problem; institutional complex, difficult to repair. High-Speed ??circulating within the torque converter hydraulic oil will generate heat, so as to use the specifi

26、ed high temperature hydraulic oil. In addition, if the car can not be started due to battery power shortage, you can not start with a truck or trailer bed. Hauling fault car, pay attention to the drive wheels off the ground to protect the Automatic gear from damage. (3) AMT AMT transformation, major

27、 changes in the mechanical transmission (manual transmission) based on the original manual shift control section. In the case of the overall transmission structure constant through the installation of computer-controlled robotic systems to achieve the automation of the shift. AMT is actually a robot

28、 system to complete the two movements operating the clutch and the gear selector. AMT is the production of manual wave based on the transformation, production inheritance, investment responsibility with lower production plant. AMTs core technology is computer-controlled, electronic technology and qu

29、ality will directly determine the quality of the performance and operation of the AMT. 3, the CVT The continuously variable transmission (CVT: Continuous Variable Transmission) with a step-type main difference in that: it is the speed ratio is not interrupted, but a series of discrete values, for

30、 example, has been changing from 3.455 to 0.85. CVT structure is simpler than conventional automatic transmission, smaller, neither many manual transmission gear pair, there is no automatic transmission complex planetary gear set, it depends mainly on the main driven wheel and metal band or wheel di

31、al to achieve the speed ratio stepless change. Its principle is as several sets of gear sizes watched under the control of an aggregate with a common gearbox, and a different speed ratio, like a bicycle pedal driven by the size of the wheel and the chain wheels to rotate at different speeds. Also ch

32、anges due to the different strength of the thrust generated by each group gear sizes, resulting in the transmission output speed, in order to achieve the bradycardia rotation, regardless of grade. CVT belts and variable-width ratchet power transmission, i.e., when the ratchet wheel changes the groov

33、e width of the elbow, corresponding to the shift change the contact radius of the drive wheel and the driven wheel on the driving belt, a belt ships with a rubber band, metal band and metal chain. CVT is truly stepless, it is light weight, small size, fewer parts, and AT has a high operating efficie

34、ncy, lower fuel consumption. CVT disadvantage is obvious, is the transmission belt can be easily damaged, can not withstand a greater load, low power and low torque vehicles can only be restricted to about 1 liter of displacement, so the share of the automatic transmission 4. After the major car com

35、panies vigorously research in recent years, the situation has improved. CVT will be the development direction of the automatic transmission. Domestic vehicle models equipped with the CVT, such as the Nissan Teana, Sylphy, X-Trail full range of models, FAW-Volkswagen, Audi, the Guangqi Honda Fit, Sou

36、th Fiat Siena, Pa Baclofen, Chery Cowin. The main structure and working principle of the CVT (1) steel belt CVT The CVT is a combination of pulleys and a steel strip, power is transmitted to replace the conventional gear device. The main components of the basic member of the including capstan grou

37、p, a driven wheel set, a metal band, and a hydraulic pump, etc.. Metal band by the two beams of metal rings and hundreds of sheet metal. Capstan group and a driven wheel set by the movable disc and the fixed rent, close to one side of the pulley and the cylinder can slide on the shaft, the other sid

38、e is fixed. Movable plate and the fixed plate cone structure, the cone forming a V-groove to engage with the V-shaped metal transmission belt. The power output of the engine output shaft is first passed to the capstan of the CVT, and then is transmitted to the driven wheel through a V-type power tra

39、nsmission belt, and finally via the gear unit, the differential is transmitted to the wheels to drive the car. Through the capstan and the driven wheel when the movable disc for axial movement to change the working radius of the capstan and the tapered surface of the driven pulley with a V-type driv

40、e belt engaging, thereby changing the transmission ratio. The amount of axial movement of the movable platen is needed by the driver through the control system to adjust the capstan, the follower wheel cylinder of the hydraulic pump pressure to achieve. Continuously adjusted in order to achieve a co

41、ntinuously variable transmission can be achieved due to the working radius of drive pulley and driven pulley. In the the CVT hydraulic system, the role of the slave cylinder to control the tension of the metal band, in order to ensure the efficient and reliable delivery of power from the engine.

42、Active cylinder to control the position of the driving bevel wheel moves axially along the V-groove move in the the capstan group metal band, due to the constant length of the metal strip, a group of the driven wheel in the opposite direction on the metal strip along the V-groove changes. Change the

43、 radius of gyration of the metal strip in the the capstan group and a driven wheel set on the continuous variation of the speed ratio. When the car is started, the small working radius of the driving wheel, the transmission can get a larger gear ratio, thus ensuring the drive axle to have enough tor

44、que to ensure the car has a higher acceleration. As the speed increases, the capstan working radius is gradually reduced, the working radius of the driven wheel increases accordingly, and the CVT transmission is decreased so that the car can travel at higher speeds. (2) wheel rotary CVT Can be u

45、sed to deliver more power and torque applicable in a larger displacement automobiles. This CVT combination of turntable and roller transfer drive torque and change the transmission ratio. It is changed by moving the power roller transmission ratio, input dial to the power roller force is applied in

46、a timely manner, so that CVT gear ratio change of the reaction faster than the strip-type CVT, in order to achieve the drivers accelerator input of the transmission ratio changes linearly. In addition, similar to the strip-drive CVT, the continuous change of the transmission ratio so that the driver

47、 can enjoy seamless smooth shifting, without any shift shock. Engine power transmitted to an input dial input dial to the rotational movement of the transmitting power to the wheel, and then passed through the rollers to the output of the turntable. By continuously changing the inclination angle of

48、 the power roller, CVT performs a smooth and continuous gear ratio changes. The size of the contact circle between the points of contact between the input wheel and the power roller circle size and the output of the dial and the power roller is changed according to the change of the inclination angl

49、e of the power roller. The size ratio of the circle corresponding to the input the turntable and output rotational speed ratio of the turntable, the rotational speed ratio is equal to the drive ratio. When the the output dial circle is larger, the rotation of the output dial slower than the input di

50、al, which is equivalent to the traditional low-end of the transmission. Conversely, output dial circle small, the rotation of the output dial faster than the input dial, which is equivalent to the high-end of the traditional transmission. The momentum wheel is supported on the trunnion connected ab

51、ove and below the assembly and the hydraulic servo piston can move up and down. Power roller, this configuration allows each roller rotating around the trunnion. When the power roller axis through the wheel center, does not produce the force of the tilt of the wheel. Accordingly, since the wheel t

52、ilt remains unchanged, it is no change in the transmission ratio. Since the high-speed rotation of the turntable, as long as the wheel moves up or down. 0.1mm to 1.0mm, can be tilted. This immediate response to a gear ratio change instruction, the EXTROID CVT cause particularly rapid transmission r

53、atio change. The inclination angle of the power roller hydraulic mechanism for manipulation. Despite the transmission ratio is changed by tilting the power roller, but not directly to the wheel afterburner. Instead, the force generated using the turntable so that the inclined roller when the vertic

54、al movement of the wheel from the center axis, the turntable on the roller tilt. As the high-speed rotary dial, dial the forces generated by the wheel movement and force the hours immediately tilt, so we can quickly feel the transmission ratio changes significantly. When the drivers accelerator inpu

55、t, and the linear acceleration and deceleration. 中文譯文 無級變速器 無級變速技術(shù)，它采用傳動帶和工作直徑可變的主、從動輪相配合來傳遞動力，可以實現(xiàn)傳動比的連續(xù)改變，從而得到傳動系與發(fā)動機(jī)工況的最佳匹配。常見的無級變速器有液力機(jī)械式無級變速器和金屬帶式無級變速器 自動變速器，按齒輪變速系統(tǒng)的控制方式，它可以分為液控液壓自動變速器和電控液壓自動變速器；按傳動比的變化方式又可分為有級式自動變速器和無級式自動變速器。因此，無級變速器實際上是自動變速器的一種，但它比常見的自動變速器要復(fù)雜得多，技術(shù)上也更為先進(jìn)。 　　 無級變速器與常見

56、的液壓自動變速器最大的不同是在結(jié)構(gòu)上，后者是由液壓控制的齒輪變速系統(tǒng)構(gòu)成，還是有擋位的，它所能實現(xiàn)的是在兩擋之間的無級變速，而無級變速器則是兩組變速輪盤和一條傳動帶組成的，比傳統(tǒng)自動變速器結(jié)構(gòu)簡單，體積更小。另外，它可以自由改變傳動比，從而實現(xiàn)全程無級變速，使車速變化更為平穩(wěn)，沒有傳統(tǒng)變速器換擋時那種“頓”的感覺。 　　為實現(xiàn)無級變速，按傳動方式可采用液體傳動、電力傳動和機(jī)械傳動三種方式。 液體傳動 　　液體傳動分為兩類：一類是液壓式，主要是由泵和馬達(dá)組成或者由閥和泵組成的變速傳動裝置，適用于中小功率傳動。另一類為液力式，采用液力耦合器或液力矩進(jìn)行變速傳動，適用于大功率（幾百至幾千千瓦）

57、。 液體傳動的主要特點是：調(diào)速范圍大，可吸收沖擊和防止過載，傳動效率較高，壽命長，易于實現(xiàn)自動化：制造精度要求高，價格較貴，輸出特性為恒轉(zhuǎn)矩，滑動率較大，運(yùn)轉(zhuǎn)時容易發(fā)生漏油。 電力傳動 　　電力傳動基本上分為三類：一類是電磁滑動式，它是在異步電動機(jī)中安裝一電磁滑差離合器，通過改變其勵磁電流來調(diào)速，這屬于一種較為落后的調(diào)速方式。其特點結(jié)構(gòu)簡單，成本低，操作維護(hù)方便：滑動最大，效率低，發(fā)熱嚴(yán)重，不適合長期負(fù)載運(yùn)轉(zhuǎn)，故一般只用于小功率傳動。 二類是直流電動機(jī)式，通過改變磁通或改變電樞電壓實現(xiàn)調(diào)速。其特點是調(diào)速范圍大，精度也較高，但設(shè)備復(fù)雜，成本高，維護(hù)困難，一般用于中等功率范圍（幾十至幾百千瓦）

58、，現(xiàn)已逐步被交流電動機(jī)式替代。 三類是交流電動機(jī)式，通過變極、調(diào)壓和變頻進(jìn)行調(diào)速。實際應(yīng)用最多者為變頻調(diào)速，即采用一變幅器獲得變幅電源，然后驅(qū)動電動機(jī)變速。其特點是調(diào)速性能好、范圍大、效率較高，可自動控制，體積小，適用功率范圍寬：機(jī)械特性在降速段位恒轉(zhuǎn)矩，低速時效率低且運(yùn)轉(zhuǎn)不夠平穩(wěn)，價格較高，維修需專業(yè)人員。近年來，變頻器作為一種先進(jìn)、優(yōu)良的變速裝置迅速發(fā)展，對機(jī)械無級變速器產(chǎn)生了一定的沖擊。 機(jī)械傳動 　　機(jī)械傳動的特點主要是：轉(zhuǎn)速穩(wěn)定，滑動率小，工作可靠，具有恒功率機(jī)械特性，傳動效率較高，而且結(jié)構(gòu)簡單，維修方便，價格相對便宜；但零部件加工及潤滑要求較高，承載能力較低，抗過載及耐沖擊性較

59、差，故一般適合于中、小功率傳動。 1、MT 　　手動變速器（MT：Manual Transmission）采用齒輪組，由于每擋齒輪組的齒數(shù)是固定的，所以各擋速比是個固定值（也就是所謂的“級”）。比如，一擋速比是3.455，二擋是2.056，再到五擋的0.85，這些數(shù)字再乘上主減速比就是汽車動力傳動系統(tǒng)的總傳動比，5擋變速器共有5個值（即有5級），所以說它是有級變速器。 　　手動變速器是最常見的變速器，相對AT和CVT而言，它的結(jié)構(gòu)最簡單，主要由輸入軸、軸出軸和中間軸、各軸軸承、各擋齒輪、同步器、換擋操縱機(jī)構(gòu)組成。手動變速器故障率相對較低，使用成本也較低?！? 2、AT 自動變速器（A

60、T:Automatic Transmission）可以自動升擋和降擋，電腦主要根據(jù)車速和負(fù)荷（油門踏板的行程）進(jìn)行升降擋控制，同時還要參考變速器油溫、換擋模式等多種信號。AT與MT的相同點就是二者都是有級式變速器，只不過AT在各個擋位都有一段連續(xù)的速比變化，而且能根據(jù)車速的快慢來自動實現(xiàn)擋位的增減，可以消除手擋車“頓挫”的變擋感覺。 　　（1）AT的結(jié)構(gòu)： 　　與手動波相比，液力自動波（AT）在結(jié)構(gòu)和使用上有很大的不同。手動波主要由齒輪和軸組成，通過不同的齒輪組合產(chǎn)生變速變矩；而AT是由液力變扭器、行星齒輪和液壓操縱系統(tǒng)組成，通過液力傳遞和齒輪組合的方式來達(dá)到變速變矩。其中液力變扭器是AT

61、最具特點的部件，它由泵輪、渦輪和導(dǎo)輪等構(gòu)件組成，直接輸入發(fā)動機(jī)動力傳遞扭矩和離合作用。 　　（2）AT的優(yōu)缺點 ： 　　AT不用離合器換檔，檔位少變化大，連接平穩(wěn)，因此操作容易，既給開車人帶來方便，也給坐車人帶來舒適。 　　但缺點也多，一是對速度變化反應(yīng)較慢，沒有手動波靈敏，因此許多玩車人士喜歡開手動波車；二是費(fèi)油不經(jīng)濟(jì)，傳動效率低變矩范圍有限，近年引入電子控制技術(shù)改善了這方面的問題；三是機(jī)構(gòu)復(fù)雜，修理困難。在液力變扭器內(nèi)高速循環(huán)流動的液壓油會產(chǎn)生高溫，所以要用指定的耐高溫液壓油。另外，如果汽車因蓄電池缺電不能啟動，不能用推車或拖車的方法啟動。如果拖運(yùn)故障車，要注意使驅(qū)動輪脫離地面，以保

62、護(hù)自動波齒輪不受損害。 ?。?）AMT 　　AMT在機(jī)械變速器（手動波）原有基礎(chǔ)上進(jìn)行改造，主要改變手動換檔操縱部分。即在總體傳動結(jié)構(gòu)不變的情況下通過加裝微機(jī)控制的自動操縱系統(tǒng)來實現(xiàn)換擋的自動化。因此AMT實際上是由一個機(jī)器人系統(tǒng)來完成操作離合器和選檔的兩個動作。由于AMT能在現(xiàn)生產(chǎn)的手動波基礎(chǔ)上進(jìn)行改造，生產(chǎn)繼承性好，投入的責(zé)用也較低，容易被生產(chǎn)廠接受。AMT的核心技術(shù)是微機(jī)控制，電子技術(shù)及質(zhì)量將直接決定AMT的性能與運(yùn)行質(zhì)量。　　 3、CVT 無級變速器(CVT：Continuous Variable Transmission)與有級式的主要區(qū)別在于：它的速比不是間斷的，而是一系

63、列連續(xù)的值，譬如可以從3.455一直變化到0.85。CVT結(jié)構(gòu)比傳統(tǒng)自動變速器簡單，體積更小，它既沒有手動變速器的眾多齒輪副，也沒有自動變速器復(fù)雜的行星齒輪組，它主要靠主、從動輪和金屬帶或滾輪轉(zhuǎn)盤來實現(xiàn)速比的無級變化。 　　其原理是與普通的變速箱一樣大小不一的幾組齒輪在操控下有分有合，形成不同的速比，像自行車的踏板經(jīng)大小輪盤與鏈條帶動車輪以不同的速度旋轉(zhuǎn)。由于不同的力度對各組齒輪產(chǎn)生的推力大小不一，致使變速箱輸出的轉(zhuǎn)速也隨之變化，從而實現(xiàn)不分檔次的徐緩轉(zhuǎn)動。 　　CVT采用傳動帶和可變槽寬的棘輪進(jìn)行動力傳遞，即當(dāng)棘輪變化槽寬肘，相應(yīng)改變驅(qū)動輪與從動輪上傳動帶的接觸半徑進(jìn)行變速，傳動帶一般用

64、橡膠帶、金屬帶和金屬鏈等。CVT是真正無級化了，它的優(yōu)點是重量輕，體積小，零件少，與AT比較具有較高的運(yùn)行效率，油耗較低。但CVT的缺點也是明顯的，就是傳動帶很容易損壞，不能承受較大的載荷，只能限用于在1升排量左右的低功率和低扭矩汽車，因此在自動變速器占有率約4以下。近年來經(jīng)過各大汽車公司的大力研究，情況有所改善。CVT將是自動變速箱的發(fā)展方向。 　　國內(nèi)目前有多款車型裝備了CVT，如東風(fēng)日產(chǎn)天籟、軒逸、奇駿等全系列車型，一汽大眾奧迪，廣汽本田飛度，南汽菲亞特西耶那、帕力奧，奇瑞旗云等。 CVT的主要結(jié)構(gòu)和工作原理 （1）鋼帶式CVT 這種CVT是帶輪和鋼帶的組合，取代常規(guī)的齒輪裝置傳

65、遞動力。主要部件包括主動輪組、從動輪組、金屬帶和液壓泵等基本部件。 　　金屬帶由兩束金屬環(huán)和幾百個金屬片構(gòu)成。主動輪組和從動輪組都由可動盤和固定盤組成，與油缸靠近的一側(cè)帶輪可以在軸上滑動，另一側(cè)則固定。可動盤與固定盤都是錐面結(jié)構(gòu)，它們的錐面形成V型槽來與V型金屬傳動帶嚙合。發(fā)動機(jī)輸出軸輸出的動力首先傳遞到CVT的主動輪，然后通過V型傳動帶傳遞到從動輪，最后經(jīng)減速器、差速器傳遞給車輪來驅(qū)動汽車。工作時通過主動輪與從動輪的可動盤作軸向移動來改變主動輪、從動輪錐面與V型傳動帶嚙合的工作半徑，從而改變傳動比?？蓜颖P的軸向移動量是由駕駛者根據(jù)需要通過控制系統(tǒng)調(diào)節(jié)主動輪、從動輪液壓泵油缸壓力來實現(xiàn)的。由

66、于主動輪和從動輪的工作半徑可以實現(xiàn)連續(xù)調(diào)節(jié)，從而實現(xiàn)了無級變速。 　　在金屬帶式無級變速器的液壓系統(tǒng)中，從動油缸的作用是控制金屬帶的張緊力，以保證來自發(fā)動機(jī)的動力高效、可靠的傳遞。主動油缸控制主動錐輪的位置沿軸向移動，在主動輪組金屬帶沿V型槽移動，由于金屬帶的長度不變，在從動輪組上金屬帶沿V型槽向相反的方向變化。金屬帶在主動輪組和從動輪組上的回轉(zhuǎn)半徑發(fā)生變化，實現(xiàn)速比的連續(xù)變化。 　　汽車開始起步時，主動輪的工作半徑較小，變速器可以獲得較大的傳動比，從而保證驅(qū)動橋能夠有足夠的扭矩來保證汽車有較高的加速度。隨著車速的增加，主動輪的工作半徑逐漸減小，從動輪的工作半徑相應(yīng)增大，CVT的傳動比下降，使得汽車能夠以更高的速度行駛。 （2）滾輪轉(zhuǎn)盤式CVT 可用來傳遞更大的功率和扭矩，適用于較大排量的汽車上。這種CVT使用轉(zhuǎn)盤和滾輪的結(jié)合傳遞驅(qū)動扭矩并改變傳動比。它通過移動動力滾輪改變傳動比，輸入轉(zhuǎn)盤給動力滾輪及時施加作用力，所以這種CVT對傳動比變化的反應(yīng)比鋼帶式CVT更快，從而實現(xiàn)駕駛員加速器輸入的傳動比線性變化。此外，與鋼帶驅(qū)動式CVT類似，傳動比的連續(xù)