機(jī)械外文翻譯文獻(xiàn)翻譯無(wú)級(jí)變速器
機(jī)械專(zhuān)業(yè)中英文文獻(xiàn)翻譯英文原文Stepless speed technologyStepless 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. 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 transmissionAutomatic transmission is 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 levels 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 transmission 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 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 classificationTo realize stepless speed, driving mode can be adopted according to the liquid transmission, power transmission and mechanical drive three ways.Liquid transmissionLiquid 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 of 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 absorb 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 transmissionPower 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 characteristics 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 armature 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 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 efficiency, 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 an advanced, excellent variable speed device rapid development of machinery, step-less transmission produced a certain impact.Mechanical transmissionThe main characteristic of the mechanical transmission is stable, rotate speed sliding rate, reliable, and has small constant power mechanical properties, 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 transmission.1, MTThe 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 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 axis 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, ATAutomatic transmission (AT: Automatic Transmission) automatic upshifts 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 variation 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 structure 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 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 connection, 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 transmission 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 specified 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 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 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 quality will directly determine the quality of the performance and operation of the AMT. 3, the CVTThe 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 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 dial 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 changes 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 groove 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 efficiency, 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 companies 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, South Fiat Siena, Pa Baclofen, Chery Cowin.The main structure and working principle of the CVT (1) steel belt CVTThe 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 group, 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 side 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 transmission 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 drive 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 continuously 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. 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 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 torque 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 CVTCan be used 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 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 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 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 angle 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 dial, 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 above 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 tilt 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 ratio 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 vertical 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 input, and the linear acceleration and deceleration.中文譯文無(wú)級(jí)變速器無(wú)級(jí)變速技術(shù),它采用傳動(dòng)帶和工作直徑可變的主、從動(dòng)輪相配合來(lái)傳遞動(dòng)力,可以實(shí)現(xiàn)傳動(dòng)比的連續(xù)改變,從而得到傳動(dòng)系與發(fā)動(dòng)機(jī)工況的最佳匹配。常見(jiàn)的無(wú)級(jí)變速器有液力機(jī)械式無(wú)級(jí)變速器和金屬帶式無(wú)級(jí)變速器自動(dòng)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(dòng)變速器和電控液壓自動(dòng)變速器;按傳動(dòng)比的變化方式又可分為有級(jí)式自動(dòng)變速器和無(wú)級(jí)式自動(dòng)變速器。因此,無(wú)級(jí)變速器實(shí)際上是自動(dòng)變速器的一種,但它比常見(jiàn)的自動(dòng)變速器要復(fù)雜得多,技術(shù)上也更為先進(jìn)。 無(wú)級(jí)變速器與常見(jiàn)的液壓自動(dòng)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(shí)現(xiàn)的是在兩擋之間的無(wú)級(jí)變速,而無(wú)級(jí)變速器則是兩組變速輪盤(pán)和一條傳動(dòng)帶組成的,比傳統(tǒng)自動(dòng)變速器結(jié)構(gòu)簡(jiǎn)單,體積更小。另外,它可以自由改變傳動(dòng)比,從而實(shí)現(xiàn)全程無(wú)級(jí)變速,使車(chē)速變化更為平穩(wěn),沒(méi)有傳統(tǒng)變速器換擋時(shí)那種“頓”的感覺(jué)。為實(shí)現(xiàn)無(wú)級(jí)變速,按傳動(dòng)方式可采用液體傳動(dòng)、電力傳動(dòng)和機(jī)械傳動(dòng)三種方式。液體傳動(dòng)液體傳動(dòng)分為兩類(lèi):一類(lèi)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(dòng)裝置,適用于中小功率傳動(dòng)。另一類(lèi)為液力式,采用液力耦合器或液力矩進(jìn)行變速傳動(dòng),適用于大功率(幾百至幾千千瓦)。 液體傳動(dòng)的主要特點(diǎn)是:調(diào)速范圍大,可吸收沖擊和防止過(guò)載,傳動(dòng)效率較高,壽命長(zhǎng),易于實(shí)現(xiàn)自動(dòng)化:制造精度要求高,價(jià)格較貴,輸出特性為恒轉(zhuǎn)矩,滑動(dòng)率較大,運(yùn)轉(zhuǎn)時(shí)容易發(fā)生漏油。電力傳動(dòng)電力傳動(dòng)基本上分為三類(lèi):一類(lèi)是電磁滑動(dòng)式,它是在異步電動(dòng)機(jī)中安裝一電磁滑差離合器,通過(guò)改變其勵(lì)磁電流來(lái)調(diào)速,這屬于一種較為落后的調(diào)速方式。其特點(diǎn)結(jié)構(gòu)簡(jiǎn)單,成本低,操作維護(hù)方便:滑動(dòng)最大,效率低,發(fā)熱嚴(yán)重,不適合長(zhǎng)期負(fù)載運(yùn)轉(zhuǎn),故一般只用于小功率傳動(dòng)。 二類(lèi)是直流電動(dòng)機(jī)式,通過(guò)改變磁通或改變電樞電壓實(shí)現(xiàn)調(diào)速。其特點(diǎn)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),現(xiàn)已逐步被交流電動(dòng)機(jī)式替代。 三類(lèi)是交流電動(dòng)機(jī)式,通過(guò)變極、調(diào)壓和變頻進(jìn)行調(diào)速。實(shí)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(dòng)電動(dòng)機(jī)變速。其特點(diǎn)是調(diào)速性能好、范圍大、效率較高,可自動(dòng)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(shí)效率低且運(yùn)轉(zhuǎn)不夠平穩(wěn),價(jià)格較高,維修需專(zhuān)業(yè)人員。近年來(lái),變頻器作為一種先進(jìn)、優(yōu)良的變速裝置迅速發(fā)展,對(duì)機(jī)械無(wú)級(jí)變速器產(chǎn)生了一定的沖擊。機(jī)械傳動(dòng)機(jī)械傳動(dòng)的特點(diǎn)主要是:轉(zhuǎn)速穩(wěn)定,滑動(dòng)率小,工作可靠,具有恒功率機(jī)械特性,傳動(dòng)效率較高,而且結(jié)構(gòu)簡(jiǎn)單,維修方便,價(jià)格相對(duì)便宜;但零部件加工及潤(rùn)滑要求較高,承載能力較低,抗過(guò)載及耐沖擊性較差,故一般適合于中、小功率傳動(dòng)。1、MT手動(dòng)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(gè)固定值(也就是所謂的“級(jí)”)。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(chē)動(dòng)力傳動(dòng)系統(tǒng)的總傳動(dòng)比,5擋變速器共有5個(gè)值(即有5級(jí)),所以說(shuō)它是有級(jí)變速器。手動(dòng)變速器是最常見(jiàn)的變速器,相對(duì)AT和CVT而言,它的結(jié)構(gòu)最簡(jiǎn)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(dòng)變速器故障率相對(duì)較低,使用成本也較低。 2、AT自動(dòng)變速器(AT:Automatic Transmission)可以自動(dòng)升擋和降擋,電腦主要根據(jù)車(chē)速和負(fù)荷(油門(mén)踏板的行程)進(jìn)行升降擋控制,同時(shí)還要參考變速器油溫、換擋模式等多種信號(hào)。AT與MT的相同點(diǎn)就是二者都是有級(jí)式變速器,只不過(guò)AT在各個(gè)擋位都有一段連續(xù)的速比變化,而且能根據(jù)車(chē)速的快慢來(lái)自動(dòng)實(shí)現(xiàn)擋位的增減,可以消除手擋車(chē)“頓挫”的變擋感覺(jué)。(1)AT的結(jié)構(gòu):與手動(dòng)波相比,液力自動(dòng)波(AT)在結(jié)構(gòu)和使用上有很大的不同。手動(dòng)波主要由齒輪和軸組成,通過(guò)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(guò)液力傳遞和齒輪組合的方式來(lái)達(dá)到變速變矩。其中液力變扭器是AT最具特點(diǎn)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(dòng)機(jī)動(dòng)力傳遞扭矩和離合作用。(2)AT的優(yōu)缺點(diǎn) :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(kāi)車(chē)人帶來(lái)方便,也給坐車(chē)人帶來(lái)舒適。但缺點(diǎn)也多,一是對(duì)速度變化反應(yīng)較慢,沒(méi)有手動(dòng)波靈敏,因此許多玩車(chē)人士喜歡開(kāi)手動(dòng)波車(chē);二是費(fèi)油不經(jīng)濟(jì),傳動(dòng)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(wèn)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(dòng)的液壓油會(huì)產(chǎn)生高溫,所以要用指定的耐高溫液壓油。另外,如果汽車(chē)因蓄電池缺電不能啟動(dòng),不能用推車(chē)或拖車(chē)的方法啟動(dòng)。如果拖運(yùn)故障車(chē),要注意使驅(qū)動(dòng)輪脫離地面,以保護(hù)自動(dòng)波齒輪不受損害。(3)AMTAMT在機(jī)械變速器(手動(dòng)波)原有基礎(chǔ)上進(jìn)行改造,主要改變手動(dòng)換檔操縱部分。即在總體傳動(dòng)結(jié)構(gòu)不變的情況下通過(guò)加裝微機(jī)控制的自動(dòng)操縱系統(tǒng)來(lái)實(shí)現(xiàn)換擋的自動(dòng)化。因此AMT實(shí)際上是由一個(gè)機(jī)器人系統(tǒng)來(lái)完成操作離合器和選檔的兩個(gè)動(dòng)作。由于AMT能在現(xiàn)生產(chǎn)的手動(dòng)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(wú)級(jí)變速器(CVT:Continuous Variable Transmission)與有級(jí)式的主要區(qū)別在于:它的速比不是間斷的,而是一系列連續(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(dòng)變速器簡(jiǎn)單,體積更小,它既沒(méi)有手動(dòng)變速器的眾多齒輪副,也沒(méi)有自動(dòng)變速器復(fù)雜的行星齒輪組,它主要靠主、從動(dòng)輪和金屬帶或滾輪轉(zhuǎn)盤(pán)來(lái)實(shí)現(xiàn)速比的無(wú)級(jí)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(chē)的踏板經(jīng)大小輪盤(pán)與鏈條帶動(dòng)車(chē)輪以不同的速度旋轉(zhuǎn)。由于不同的力度對(duì)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(shí)現(xiàn)不分檔次的徐緩轉(zhuǎn)動(dòng)。CVT采用傳動(dòng)帶和可變槽寬的棘輪進(jìn)行動(dòng)力傳遞,即當(dāng)棘輪變化槽寬肘,相應(yīng)改變驅(qū)動(dòng)輪與從動(dòng)輪上傳動(dòng)帶的接觸半徑進(jìn)行變速,傳動(dòng)帶一般用橡膠帶、金屬帶和金屬鏈等。CVT是真正無(wú)級(jí)化了,它的優(yōu)點(diǎn)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(diǎn)也是明顯的,就是傳動(dòng)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(chē),因此在自動(dòng)變速器占有率約4以下。近年來(lái)經(jīng)過(guò)各大汽車(chē)公司的大力研究,情況有所改善。CVT將是自動(dòng)變速箱的發(fā)展方向。國(guó)內(nèi)目前有多款車(chē)型裝備了CVT,如東風(fēng)日產(chǎn)天籟、軒逸、奇駿等全系列車(chē)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)的齒輪裝置傳遞動(dòng)力。主要部件包括主動(dòng)輪組、從動(dòng)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(gè)金屬片構(gòu)成。主動(dòng)輪組和從動(dòng)輪組都由可動(dòng)盤(pán)和固定盤(pán)組成,與油缸靠近的一側(cè)帶輪可以在軸上滑動(dòng),另一側(cè)則固定??蓜?dòng)盤(pán)與固定盤(pán)都是錐面結(jié)構(gòu),它們的錐面形成V型槽來(lái)與V型金屬傳動(dòng)帶嚙合。發(fā)動(dòng)機(jī)輸出軸輸出的動(dòng)力首先傳遞到CVT的主動(dòng)輪,然后通過(guò)V型傳動(dòng)帶傳遞到從動(dòng)輪,最后經(jīng)減速器、差速器傳遞給車(chē)輪來(lái)驅(qū)動(dòng)汽車(chē)。工作時(shí)通過(guò)主動(dòng)輪與從動(dòng)輪的可動(dòng)盤(pán)作軸向移動(dòng)來(lái)改變主動(dòng)輪、從動(dòng)輪錐面與V型傳動(dòng)帶嚙合的工作半徑,從而改變傳動(dòng)比??蓜?dòng)盤(pán)的軸向移動(dòng)量是由駕駛者根據(jù)需要通過(guò)控制系統(tǒng)調(diào)節(jié)主動(dòng)輪、從動(dòng)輪液壓泵油缸壓力來(lái)實(shí)現(xiàn)的。由于主動(dòng)輪和從動(dòng)輪的工作半徑可以實(shí)現(xiàn)連續(xù)調(diào)節(jié),從而實(shí)現(xiàn)了無(wú)級(jí)變速。在金屬帶式無(wú)級(jí)變速器的液壓系統(tǒng)中,從動(dòng)油缸的作用是控制金屬帶的張緊力,以保證來(lái)自發(fā)動(dòng)機(jī)的動(dòng)力高效、可靠的傳遞。主動(dòng)油缸控制主動(dòng)錐輪的位置沿軸向移動(dòng),在主動(dòng)輪組金屬帶沿V型槽移動(dòng),由于金屬帶的長(zhǎng)度不變,在從動(dòng)輪組上金屬帶沿V型槽向相反的方向變化。金屬帶在主動(dòng)輪組和從動(dòng)輪組上的回轉(zhuǎn)半徑發(fā)生變化,實(shí)現(xiàn)速比的連續(xù)變化。汽車(chē)開(kāi)始起步時(shí),主動(dòng)輪的工作半徑較小,變速器可以獲得較大的傳動(dòng)比,從而保證驅(qū)動(dòng)橋能夠有足夠的扭矩來(lái)保證汽車(chē)有較高的加速度。隨著車(chē)速的增加,主動(dòng)輪的工作半徑逐漸減小,從動(dòng)輪的工作半徑相應(yīng)增大,CVT的傳動(dòng)比下降,使得汽車(chē)能夠以更高的速度行駛。 (2)滾輪轉(zhuǎn)盤(pán)式CVT 可用來(lái)傳遞更大的功率和扭矩,適用于較大排量的汽車(chē)上。這種CVT使用轉(zhuǎn)盤(pán)和滾輪的結(jié)合傳遞驅(qū)動(dòng)扭矩并改變傳動(dòng)比。它通過(guò)移動(dòng)動(dòng)力滾輪改變傳動(dòng)比,輸入轉(zhuǎn)盤(pán)給動(dòng)力滾輪及時(shí)施加作用力,所以這種CVT對(duì)傳動(dòng)比變化的反應(yīng)比鋼帶式CVT更快,從而實(shí)現(xiàn)駕駛員加速器輸入的傳動(dòng)比線性變化。此外,與鋼帶驅(qū)動(dòng)式CVT類(lèi)似,傳動(dòng)比的連續(xù)