Next, we will take you through the history of CVT technology and understand the "past life" of Nissan CVT.
1992, Nissan developed a new generation CVT gearbox, named "N-CVT" (using electromagnetic clutch), which is a small CVT that can intelligently bear small torque. At that time, it was mainly carried on some small-displacement vehicles such as Ma Chi.
By 1997, Nissan has developed a CVT gearbox that can withstand large torque and named it "Hyper CVT". Hesitant and innovative use of high-rigidity materials to transfer steel belts greatly improves the maximum torque. This Hyper CVT can be mounted on a 2.0L displacement vehicle, which was a breakthrough in the industry at that time.
In 2000, Nissan pioneered the roller CVT, which was called "EXTROID-CVT". This kind of gearbox uses rollers to transmit power and can bear more torque. Perhaps because of the cost, EXTROID-CVT has not been widely used.
After 2002, it can be said that Nissan CVT gearbox has entered a stage of rapid development. Since then, CVT gearbox has been widely used in its models. Through the application of "thrust" high-strength steel belt technology, CVT gearbox (called "XTRONIC-CVT") can be installed on medium and large displacement vehicles, and Nissan CVT has thus entered the "XTRONIC-CVT" era.
By 2009, Nissan pioneered CVT with auxiliary gearbox (code name CVT7), which can realize a wide transmission ratio of 7.3 and a lightweight and miniaturized design. Later, it was mainly used in vehicles with displacement below 1.6L, and now it has basically replaced the previous generation of small CVT gearboxes, which are mainly used in Sunshine, Xinsylphy, Converse, Tiida and other vehicles.
In China, Nissan introduced a new generation XTRONIC-CVT (code name CVT8), which has excellent fuel economy and ride comfort, and is mainly used in medium and large displacement vehicles. At present, this is the CVT gearbox used by the new generation of Teana. It is understood that this gearbox will replace CVT2 and CVT3 in the future and be installed on 2.5L-3.5L models.
Throughout the development history of Nissan CVT gearbox, the first stage is basically to continuously improve the torque transmitted by CVT gearbox, while the latter stage is more focused on improving the transmission efficiency and speed ratio range of CVT to obtain better fuel economy and driving performance.
Advantages of CVT gearbox:
1, economy
CVT can realize stepless speed change in a wide range, so as to obtain the best matching between the transmission system and the engine working conditions and improve the fuel economy of the whole vehicle.
2. Dynamic
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 of the car. Because of CVT's stepless speed change characteristics, the transmission ratio of maximum reserve power can be obtained, so the dynamic performance of CVT is obviously superior to that of mechanical transmission (MT) and automatic transmission (at).
3. Emissions
CVT has a wide working range, reaching the world-leading 7.3: 1, which can keep the engine in the best working condition at all times, thus improving the combustion process and reducing exhaust emissions. The actual test shows that the exhaust emission of CVT is about 10% lower than that of the car equipped with 4-AT.
4. expenses
The CVT system has a simple structure, the number of parts is about 40% less than that of at transmission, and the quality of the whole vehicle is also reduced. Because the system can save fuel, with the mass production and the innovation of system and materials, the production cost of CVT parts (such as transmission belt or chain, driving wheel, driven wheel, hydraulic pump, etc.) will be reduced by 20%-30%.
5. Driving comfort
Because the speed ratio of CVT is continuously changing, the acceleration or deceleration process of the car is very gentle, driving is very simple and safe, and users can get all-round driving pleasure.