CVT is decentralization
A6L: 2.0T, 2.4, 3.2fsi (except 4WD)
A4: 1.8T, 2.0T
fit: 1.3, 1.5
Tianlai: 3.5
Xuanyi: 2.0
the eighth generation Accord
Nissan qiaoke
perio (Siena, weekend wind), fit
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< H2 > expanded materials:R & d
successfully developed in & quot; 1992; K11 March & quot; & quot; N-CVT"( Using electromagnetic clutch), and began mass proction
in 1997, it was the first time to successfully develop & quot; Hyper CVT (hydraulic torque converter)
in 2000, we successfully developed & quot; EXTROID-CVT" Nissan also developed & quot; XTRONIC-CVT"， It has been successfully applied to 3.5L large displacement vehicle
xtronic - CVT is achieved by & quot; Torque Converter & quot; And & quot; Steel belt, pulley & quot; Tianlai car adopts reofo9a CVT and Xuanyi adopts reofo10a automatic transmission
CVT is the stepless variable transmission, its English full name is continuous LV variable transmission, referred to as CVT. The Dutch invented this kind of transmission mechanism. The transmission with its device is also called stepless transmission or CVT. The biggest difference between this kind of transmission and ordinary automatic transmission is that it omits the complex and bulky gear combination transmission, and only uses two groups of belt wheels for transmission. By changing the contact radius of driving wheel and driven wheel, the design idea is very clever. CVT is an ideal vehicle transmission device because it can continuously change the transmission ratio, get the best match between the transmission system and the engine working condition, improve the fuel economy and power performance of the whole vehicle, improve the driver's handling convenience and the passenger's riding comfort. Like a car with stepless transmission, it has its own gears, such as parking gear P, reverse gear R, neutral gear n, and forward gear D. however, when the car moves forward automatically, it is very stable, and there is no sudden jump feeling<
at present, only Audi, fit, perio (Siena, weekend wind) and Qiyun are available in the domestic market with CVT technology< The main structure and working principle of CVT are shown in Figure 1. The system mainly includes driving wheel group, driven wheel group, metal belt, hydraulic pump and other basic components. The metal belt consists of two metal rings and hundreds of metal sheets. The driving wheel group and the driven wheel group are both composed of a movable plate and a fixed plate. The belt wheel close to the oil cylinder can slide on the shaft, while the other side is fixed. The movable disc and the fixed disc are both cone-shaped structures. Their cone-shaped surfaces form a V-shaped groove to mesh with the V-shaped metal transmission belt. The power from the engine output shaft is first transmitted to the driving wheel of CVT, then to the driven wheel through V-belt, and finally to the wheel through recer and differential to drive the car. When working, the driving wheel and the driven wheel can move axially to change the working radius of the driving wheel, the conical surface of the driven wheel and the V-belt, so as to change the transmission ratio. The axial movement of the movable disc is realized by the driver adjusting the hydraulic pump cylinder pressure of the driving wheel and the driven wheel through the control system. Because the working radius of driving wheel and driven wheel can be adjusted continuously, CVT is realized
in the hydraulic system of metal belt CVT, the function of the slave cylinder is to control the tension of the metal belt, so as to ensure the efficient and reliable transmission of power from the engine. The driving oil cylinder controls the position of the driving cone wheel to move along the axial direction, and the metal belt of the driving wheel group moves along the V-groove. Because the length of the metal belt remains unchanged, the metal belt of the driven wheel group changes along the V-groove in the opposite direction. The turning radius of the metal belt on the driving wheel group and the driven wheel group changes to realize the continuous change of the speed ratio
when the car starts to start, the working radius of the driving wheel is small, and the transmission can obtain a larger transmission ratio, so as to ensure that the drive axle can have enough torque to ensure that the car has a higher acceleration. With the increase of vehicle speed, the working radius of driving wheel decreases graally, the working radius of driven wheel increases correspondingly, and the transmission ratio of CVT decreases, so that the vehicle can drive at a higher speed< Economic
CVT can realize continuously variable transmission in a wide range, so as to obtain the best match between the transmission system and the engine working condition, and improve the fuel economy of the whole vehicle
2. Power performance
the reserve power of the car determines the climbing ability and acceleration ability of the car. The greater the reserve power of the car, the better the power performance of the car. Due to CVT's continuously variable transmission characteristics, CVT can obtain the transmission ratio with the largest reserve power, so the dynamic performance of CVT is obviously better than that of mechanical transmission (MT) and automatic transmission (at)< Emission
CVT has a wide range of speed ratio, which can make the engine work in the best working condition, thus improving the combustion process and recing the emission of exhaust gas. ZF company will test the CVT proced by itself, and its exhaust emission is about 10% less than that of the vehicle with 4-At
4. Cost
the structure of CVT system is simple, and the number of parts is less than at (about 500) (about 300). Once the automobile manufacturer starts mass proction, the cost of CVT will be less than at. Because the system can save fuel, with the large-scale proction and the innovation of system and material, the proction cost of CVT parts (such as drive belt or drive chain, driving wheel, driven wheel and hydraulic pump) will be reced by 20% - 30%< (4) the advantages and disadvantages of the widely used step automatic transmission (at)
the widely used hydraulic automatic transmission (at) does not use the clutch to shift gears, has few gears, big changes and smooth connection, so it is easy to operate, which brings convenience to the driver and comfort to the passenger. But there are also many disadvantages. First, they are slow to respond to speed changes and are not sensitive to manual waves, so many people like to drive manual waves; Second, the fuel consumption is not economical, the transmission efficiency is low, and the torque conversion range is limited; Third, the mechanism is complex and difficult to repair. In the hydraulic torque converter, the high-speed circulating hydraulic oil will proce high temperature, so the specified high-temperature hydraulic oil should be used. In addition, if the car cannot be started e to battery power shortage, it cannot be started by cart or trailer. In case of hauling the faulty vehicle, pay attention to keep the driving wheel off the ground to protect the automatic wave gear from damage< 5. The difference between CVT stepless transmission and ordinary automatic transmission. In fact, the structure and working principle of these two transmissions are completely different. CVT is simpler in structure and smaller in volume than traditional transmission. It has neither many gear pairs of manual transmission nor complex planetary gear sets of automatic transmission. It mainly relies on two sets of variable speed discs to realize stepless change of speed ratio. The old CVT usually uses rubber belt as transmission element, but the disadvantage is that the force is limited, it is easy to slip, and the transmission efficiency is low. Therefore, it can only be used in motorcycles and minicars with less horsepower. Many auto companies have been working on this problem for more than ten years. Today, Audi takes the lead in "leading the times" in this technology. It uses a unique multi piece chain belt drive belt and an excellent computer-controlled hydraulic system to transmit powerful torque. The biggest feature of CVT is fuel saving. CVT abandons the traditional automatic transmission which wastes energy and adopts new technology to improve fuel utilization. The fuel utilization rate of CVT will be higher than that of manual transmission and automatic transmission, and it can save 5% to 15% fuel compared with traditional automatic transmission
with the continuous progress of science and technology and the continuous maturity of CVT technology, CVT will eventually replace manual transmission (MT) and step automatic transmission (at), and CVT is the main trend of today's automobile development.
in CVT transmission system, the traditional gear is replaced by a pair of pulleys and a steel belt. Each pulley is actually a V-shaped structure composed of two cone-shaped discs. The engine shaft connects the small pulley and drives the large pulley through the steel belt. The mystery lies in this special pulley: the structure of CVT's transmission pulley is rather strange, which is divided into two movable halves, which can be relatively close or separated. The conical plate can be tightened or opened under the action of hydraulic thrust to extrude the steel sheet chain so as to adjust the width of V-groove. When the conical disc moves to the inside to tighten, the steel sheet chain will move to the direction outside the center of the circle (centrifugal direction) under the extrusion of the conical disc, on the contrary, it will move to the center of the circle. In this way, the diameter of the disc driven by the steel chain increases, and the transmission ratio also changes
There are differences in structure and principle between automatic transmission and CVT transmission. The following is a brief introction:
1. Structure
(1) CVT mechanical continuously variable automatic transmission mostly adopts steel belt or chain transmission for power transmission
(2) at hydraulic automatic transmission realizes automatic transmission through the combination of hydraulic transmission and planetary gear, which is generally composed of hydraulic torque converter, planetary gear mechanism, shift actuator, shift control system, shift control mechanism, etc
(3) AMT electronic control mechanical automatic transmission is improved from the traditional manual gear transmission, which combines the advantages of at (automatic) and MT (manual)
(4) al clutch automatic transmission adopts two sets of clutches, which work alternately to achieve the effect of no backlash shift
Principle (1) the engine power is transmitted by the groove of the steel belt and two cone wheels, from the primary wheel to the secondary wheel, and then to the driving wheel through the main recer to realize the power transmission. Because the center distance of the two pulleys is fixed, but the axial distance of the pulley on the shaft is variable, so the contact radius between the steel belt and the pulley is variable, so the transmission ratio is stepless adjustable(2) the automatic control system of hydro mechanical automatic transmission is usually composed of oil supply, manual gear selection, parameter adjustment, shift time control, shift quality control and other parts. The shift time control part is used to change the oil path to the shift actuator (clutch and brake), so as to realize shift control. The lock signal valve is controlled by the solenoid valve, which makes the lock up clutch in the torque converter engage and release timely
(3) in the electronic controlled mechanical automatic transmission, the intention is expressed to the microcontroller through the accelerator pedal and the selector, a large number of sensors grasp the vehicle status at all times, and the microcomputer controls the throttle opening, clutch engagement and shifting according to the best program stored in it, so as to achieve the best matching, so as to obtain excellent driving performance Smooth starting performance and fast shifting ability
(4) the al clutch automatic transmission arranges the transmission on the two input shafts connected with the two clutches according to odd and even numbers, and completes the shift process through the alternate switching of the clutches, so as to realize the power shift without interruption
(1) the characteristic of the mechanical continuously variable transmission is that the transmission ratio is not a discontinuous point, but a series of continuous values, which can better coordinate the external driving conditions and engine load of the vehicle, give full play to the potential of the engine, improve the fuel economy of the vehicle, and make the vehicle have no loopholes in the traction performance, so as to significantly improve the vehicle performance(2) at doesn't need clutch to shift gears, with less gear change and smooth connection, so it is easy to operate, which brings convenience to drivers and comfort to passengers. One of the disadvantages is slow response to speed changes, no manual gearbox sensitivity; Second, the fuel consumption is not economical, the transmission efficiency is low, and the torque conversion range is limited; Third, the mechanism is complex and difficult to repair
(3) AMT not only has the advantages of automatic transmission, but also retains the advantages of high efficiency, low cost, simple structure and easy manufacturing of the original manual transmission (4) DCT combines the advantages of at and AMT, with high transmission efficiency, simple structure and low proction cost, which not only ensures the power performance and economy of the car, but also greatly improves the comfort of the car{rrrrrrr}
extended data:
CVT transmission advantages:
1. Good fuel economy
CVT can realize continuously variable transmission in a wide range, and can obtain the best match between the transmission system and the engine working condition. CVT can adapt to various speeds of the vehicle and make the engine work in the best working condition for a long time, Therefore, the combustion efficiency of the engine can be improved and the fuel economy can be improved accordingly
Good power performanceCVT can achieve closed-loop control with the engine, fully mobilize the maximum torque of the engine, and its deceleration and torque increasing performance is obviously better than MT and at. Therefore, when assembled in SUV models that need to emphasize torque, the acceleration performance (0 ~ 100km / h) of CVT is 7.5% ~ 11.5% higher than that of at, and the acceleration performance at high speed is better than that of Mt. The power performance of CVT is better than that of manual transmission (MT) and automatic transmission (at)
Good comfortCVT can improve driving comfort. CVT has no gear, the speed change process is continuous and linear, there is no shift impact ring acceleration, there is no at's setback phenomenon ring rapid acceleration, CVT system has a wide transmission ratio, generally in the range of 2.400-0.395, low engine speed and low noise when driving at high speed, so that the driver and passengers can enjoy a quiet and comfortable journey
Good controllabilityCVT transmission is matched with hydraulic torque converter, which can amplify engine torque, so it starts faster and accelerates more smoothly. When the driver overtakes, he will not feel at downshift when he step on the accelerator. Instead, he will change the speed ratio and amplify the torque. In high-speed cornering, release the throttle without at upshift phenomenon, can maintain torque high-speed out of the corner. CVT has better engine braking effect than at. CVT can automatically detect the slope when going up and down the slope, and automatically adjust the speed ratio when going up the slope to increase the torque output; When going downhill, the engine braking torque can be increased to rece the sliding speed when going downhill, which improves the safety and handling
The reliability and service life of CVT mainly depend on the material of metal belt transmission components. According to the technical data of VDT company in the Netherlands, the new design and technology have solved the past problems of CVT. According to the trial results of 800000 sets of CVT all over the world, only 200 sets of CVT have faults, and the failure rate is 0.25%. It can be seen that the system has high quality and reliable use. With high strength and high quality materials and precision manufacturing technology, CVT can achieve the same life as the engine and free of maintenance for life6. Less harmful gas emissions
because CVT can realize the closed-loop control with the engine, it can make the engine run in the economic speed region, improve the combustion process, rece the harmful gas emissions, and prolong the service life of three-way catalyst and oxygen sensor. ZF company of Germany has tested the CVT proced by itself, and its harmful gas emission is about 10% less than that of the vehicle equipped with 4-speed automatic transmission, which greatly reces the environmental pollution
7. Low cost
the structure of CVT system is simple, and the number of parts is much less than at. Once large-scale proction starts, the cost of CVT will be smaller than at. With the large-scale proction and the innovation of system and material, the proction cost of CVT will be further reced. With the decrease of assembly and maintenance costs, its simple structure, low cost and excellent performance make the future of CVT very broad
CVT: the difference between CVT and stepwise transmission is that its transmission ratio is not a discontinuous point, but a series of continuous values, for example, it can change from 3.455 to 0.85. CVT is simpler in structure and smaller in volume than traditional transmission. It has neither many gear pairs of manual transmission nor complex planetary gear set of automatic transmission. It mainly relies on the main driving wheel, driven wheel and metal belt to realize the stepless change of speed ratio.
There are four common types of automatic transmission: at, CVT, AMT and DCT. At is widely used in cars, and at is almost synonymous with automatic transmission
at is composed of hydraulic torque converter, planetary gear and hydraulic control system, which achieves variable speed and torque through hydraulic transmission and gear combination. Among them, the hydraulic torque converter is the most important part of at, which is composed of pump wheel, turbine and guide wheel, and has the function of transmitting torque and clutch
gear
generally speaking, the gears of automatic transmission are divided into P, R, N, D, 2, 1 or L, etc
P (parking): for parking, it should be used with hand brake. It is the use of mechanical devices to lock the rotating part of the car, so that the car can not move. When the car needs to stay in a fixed position for a long time, or before leaving the cab after stopping, it should pull the hand brake and push the lever to the position P. It should be noted that the P gear can only be used when the vehicle is completely stopped, otherwise the mechanical part of the automatic transmission will be damaged. In addition, the automatic transmission is equipped with a neutral start switch, so that the car can only start the engine in P or n gear, so as to avoid the sudden forward movement of the car when it is mistakenly started in other gears. Therefore, before starting the engine, be sure to confirm whether the shift lever is in P or n gear
R (reverse): used when the vehicle is in reverse. Generally, you need to press the safety button on the paddle to move the paddle to the R gear. It should be noted that when the vehicle has not stopped completely, it is absolutely not allowed to turn to R gear by force, otherwise the transmission will be seriously damaged
n (neutral): neutral. Put the shift lever in n gear, the power between the engine and the transmission has been cut off and separated. If you stay for a short time, you can put the lever in this gear and pull out the hand brake lever. You can move your right foot away from the brake pedal for a rest
d (drive): forward gear, used for general road driving. Due to the different designs of different countries, D gear generally includes from first gear to high gear or from second gear to high gear, and will shift automatically e to the change of speed and load. Place the paddle in D gear, and the driver can control the speed as long as he controls the accelerator pedal
2 (second gear): second gear is forward gear, but the transmission can only shift between first gear and second gear, and will not jump to third gear and fourth gear. Put the paddle in the second gear, the car will start from the first gear, when the speed increases, it will automatically turn to the second gear. Second gear can be used for uphill and downhill. The advantage of this gear section is that when uphill or downhill, the vehicle will stably keep in the first or second gear position, and the transmission will not keep shifting e to the load of uphill or unbalanced speed. When going down a slope, using the resistance of low engine speed for braking will not make the car go faster and faster
1 (first gear): first gear is also a forward gear, but the transmission can only work in first gear. You can't shift to another gear. It works best when it is used in serious traffic jams and steep slopes. When going up or down the slope, the torque of the automobile engine can be fully utilized< Common sense
- maintain the automatic transmission correctly
1. Check the automatic transmission oil regularly
the automatic transmission has very strict requirements on the oil, which requires that the oil not only has the functions of lubrication, cleaning and cooling, but also has the functions of transmitting torque and hydraulic pressure to control the working performance of clutch and brake, so the automatic transmission oil is a special high-grade lubricating oil, It is usually called ATF, and there are many kinds of models, including Ford standard f model and GM standard dexron II model, which should be recognized when using. The friction coefficient varies with the type of ATF. If dexronii type is used and F type is misused, the automatic transmission will have shift impact and sudden engagement of brake and clutch. If F type is misused as dexronii type, it will cause the clutch and brake of automatic transmission to slip and accelerate the early wear of friction plate
in addition, the inspection of automatic transmission oil quantity is also very important. Different manufacturers of automatic transmission have different inspection conditions of working fluid. During the inspection, it is generally required to park the vehicle on the horizontal road when the transmission is hot (oil temperature 50 ℃ - 80 ℃), the engine idles (Honda Motor specifies engine flameout), the gear selector is placed in the P position (Nissan Motor allows it to be placed in the N position), at this time, take out the oil dipstick to wipe it, insert it again and then pull it out for inspection, and the oil level should reach the upper limit scale specified on the oil dipstick
for the inspection of oil quality, the general use and maintenance personnel can only judge from the appearance because they have no testing equipment. They can twist their fingers to feel the viscosity, smell the smell with their nose, and replace the oil if it has discolored or burnt
2. Automatic transmission oil change
most automatic transmissions require regular oil change, and the oil change cycle is generally 20000-40000 km. Before discharging the oil, preheat the transmission to the working temperature, so as to rece the viscosity of the oil and ensure that the impurities and precipitates in the oil are discharged together with the oil. In the process of preheating and refueling, the car should be parked on the level ground and the hand brake should be tightened
after the oil is discharged, remove the oil pan as appropriate, thoroughly clean the oil pan and filter screen, and then install the oil pan. When refuelling, first inject the working fluid from the refuelling port to meet the specified standard, start the engine, and move the gear selector lever to return to the P position after all gears when the engine is idling, so that the transmission can heat up quickly, and then refuel
3. Check the manual gear selection mechanism
the manual gear selection mechanism is connected from the gear selection lever to the manual valve by connecting rod or cable, and there are adjustment parts. The position of the manual handle should correspond to the position of the spring card in the automatic transmission one by one. If not, it should be adjusted. The adjustment of the manual gear selection mechanism is often ignored. Sometimes, after the repair of the automatic transmission, e to the failure to adjust the gear selection mechanism, the shifting impact force is too large, even causing accidents
4. Adjustment of brake belt
if the brake belt of automatic transmission is of adjustable structure, it should be adjusted to compensate its normal wear. The adjustment of the brake belt shall comply with the technical regulations of the manufacturer. After adjustment, the adjustment result can be judged by road test. The operation position of brake belt adjustment depends on the type of transmission
5. Check the braking performance of parking gear
when parking on the ramp, pull the gear lever to p position, and release the brake pedal at this time, the car will not slide down by itself. If you need to move the gear lever away from the P position, you should remember to press the brake pedal first, otherwise you will not be able to take it off. Therefore, you should check and repair when there is no braking performance in the parking gear< Classification
1. It can be divided into two types: step transmission and continuously variable transmission according to the type of transmission
step transmission is a transmission with limited fixed transmission ratios (generally 4-9 forward gears and 1 reverse gear). Continuously variable transmission (CVT) is a kind of transmission which can make the transmission ratio change continuously in a certain range. The application of CVT in automobile has been increasing graally< (1) automatic hydraulic transmission is a planetary gear transmission system installed behind the hydraulic torque converter< (2) mechanical continuously variable transmission (CVT)
it realizes CVT by changing the clutch and V-belt wheel radius according to the speed and throttle opening.
(3) "motor" CVT
it cancels the traditional mechanism in mechanical transmission, and replaces it with electric current to drive the wheel integrated with the motor
3. Automatic transmission can be divided into 2 forward gears, 3 forward gears and 4 forward gears according to the number of forward gears. Early automatic transmissions usually had two forward gears or three forward gears. There is no overdrive in both automatic transmissions, and the highest gear is direct. The automatic transmissions installed on new cars basically have 4-9 forward gears, that is, they are equipped with overdrive gears. Although this design makes the structure of the automatic transmission more complex, the fuel economy of the car is greatly improved e to the over speed gear< According to the type of gear transmission, automatic transmission can be divided into fixed shaft gear type and planetary gear type. Fixed axle gear type automatic transmission has larger volume, smaller maximum transmission ratio and less use. Planetary gear type automatic transmission has a compact structure and can obtain a large transmission ratio, so it is widely used in most cars< According to the control mode of gear transmission system,
(1) hydraulically controlled automatic transmission (hcat)
hcat converts the vehicle speed and throttle opening into hydraulic control signals by mechanical means; According to the size of these hydraulic control signals, each control valve in the valve plate can realize automatic shift by controlling the action of the shift actuator according to the set shift law, which is less used. This paper will not introce it
(2) eht
eht converts engine speed, throttle opening, vehicle speed, engine water temperature, automatic transmission hydraulic oil temperature and other parameters into electrical signals through various sensors, and inputs them into the computer; According to these electric signals, the computer sends electric control signals to the shift solenoid valve, oil pressure solenoid valve, etc. according to the set shift law; The shift solenoid valve and the oil pressure solenoid valve turn the electronic control signal of the computer into the hydraulic control signal, and each control valve in the valve plate controls the action of the shift actuator according to these hydraulic control signals, so as to realize the automatic shift
(3) the electronically controlled automatic transmission
realizes the shift by controlling the motor. Because it uses the motor control, there is no hydraulic oil and no slide valve box, so the structure becomes more compact and simple, and the cost is lower. Due to less use, this paper will not introce
basic composition
there are many brands and models of automatic transmission, and their external shape and internal structure are different, but their composition is basically the same, and they are all composed of hydraulic torque converter and gear type automatic transmission. Common components include hydraulic torque converter, variable speed gear mechanism, clutch, brake, one-way clutch, oil pump, filter, pipeline, control valve body, speed regulator, etc. according to the functions of these components, they can be divided into five parts: hydraulic torque converter, variable speed gear mechanism, oil supply system, TCU and shift control mechanism
1. Hydraulic torque converter is located at the front end of the automatic transmission and connected to the flywheel of the engine. Its function is similar to that of the clutch in the vehicle with manual transmission. It uses the change of kinetic energy in the process of oil circulation to transfer the engine power to the input shaft of automatic transmission, and can automatically and steplessly change the transmission ratio and torque ratio within a certain range according to the change of vehicle driving resistance. It has a certain function of deceleration and torque increase
2. Transmission gear mechanism
there are two types of transmission gear mechanism in automatic transmission: ordinary gear type and planetary gear type. Due to the large size and small maximum transmission ratio of ordinary gear transmission, only a few vehicles adopt it. Most of the automatic transmissions of cars are gear transmissions
Structure of CVT; The gearbox assembly is arranged in line with the engine. There are parallel shafts, input shaft, driving belt axle, driven belt axle and main drive shaft in the gearbox. The input shaft, the driving belt axle and the engine crankshaft are arranged in a straight line, which are composed of star gear, planetary gear and planetary carrier
the driving pulley and the driven pulley are both composed of pulleys with movable and fixed wheel surfaces, and the two pulleys are connected by steel strips. The driving pulley includes driving pulley, reverse brake and forward clutch, while the driven pulley includes driven pulley, starting clutch and intermediate driven gear integrated with parking gear. The main drive shaft is composed of the driving gear of the main recer and the intermediate driven gear
working principle; The two ends of the transmission belt are wound on a conical pulley, and the outer diameter of the pulley changes steplessly depending on the oil pressure. When starting, the diameter of the driving pulley becomes the minimum, while the diameter of the passive pulley becomes the maximum, so as to achieve a higher transmission ratio
with the increase of vehicle speed and the change of each sensor signal, the computer control system determines and controls the control oil pressure of two pulleys, and finally changes the continuous change of pulley diameter, so as to achieve stepless speed change in the whole process of speed change. In the past, e to the material, the tension and torque of the transmission belt between tapered pulleys were limited, so it can only be used in motorcycle type small displacement vehicles
extended data
the second generation CVT adopts hydraulic torque converter and electronic control, the CVT transmission torque is increased to 250nm, and the width of metal steel strip can be 3omm. Most CVTs adopt hydraulic torque converter, which can provide the best performance in torque amplification and transmission smoothness when starting. In order to improve its transmission efficiency, when the speed reaches a certain value, the lock up clutch makes the torque converter lock up, and the lock up clutch is engaged to rece the loss
at present, the latest CVT improves the transmission torque to 350nm. By improving the metal strip, increasing its power density, optimizing the starting strategy, increasing the torque overload protection dish, optimizing the hydraulic system, increasing the speed ratio range, improving the efficiency of variable speed machinery and hydraulic system, recing the clamping force of the strip and pulley, the efficiency of the whole CVT is improved, and the volume and cost are reced
The pulsating CVT includes three-phase parallel connecting rod type (gusA type) and four-phase parallel open connecting rod type (zero Max type). Among them, planetary cone type CVT has strong universality, simple structure and process, reliable operation and excellent comprehensive performance, especially it can meet the needs of various proction lines. The input power of most CVT procts is 0.18 ~ 7.5kW, and that of a few types can reach 22 ~ 30kW