What is a CVT
For many, the concept of "variator" may benew. If you also do not know what a variator is, you can say that it is a gearbox of a car that does not have steps, and the work is done by smoothly reducing or increasing the gear ratio. This feature makes it possible to use the engine power as rationally as possible, reducing fuel consumption, while providing a better dynamics of the car.
Schematic diagram of this device wasinvented by Leonardo da Vinci in the distant fifteenth century, but only in the middle of the last century the world saw the first car with this kind of transmission. At that time it was applied only on several models, however it became more widely used only in our time after making significant changes to its design.
So, what is a variator? It includes in its composition such a set of elements: a reverse gear, a unit designed to disconnect the variator and the engine, that is, oriented to ensure neutral position, variator transmission and control system.
In the work of modern cars can beone of two types of variators is used: toroidal or V-belt. The basis of V-belt is laid two pulleys, located on different axes. Between them they are connected by means of a wedge-shaped belt. Each pulley is equipped with two conical discs facing each other with their cone-shaped peaks.
The diameter of the pulley is changed by changingthe distance between the disks. If the disks are completely connected, then it will be maximum, and with full spreading - the minimum. Thus, it turns out that with a smooth change in the distances between the discs, a different gear ratio will be transmitted to the driven pulley.
Speaking of what a variator is, it's worthtell about its second form - the toroidal. It does not assume the presence of belts or chains. In the toroidal variator there are two shafts located on parallel axes, while they have spherical surfaces. The torque is transmitted by the rollers, which are clamped between the shafts. Synchronous change of the position of the rollers allows changing the gear ratio. The toroidal variator is used much less often, which is connected with its complicated device.
Variant of a variator from the automatic device: mechanisms of separation
Variator and motor are separated byseveral types of mechanisms. It is important to remember that the design features of the variator gearbox do not allow reverse movement. That is why it is usually supplemented with special mechanisms designed to provide reverse movement. This role is usually assigned to a device such as a planetary gearbox.
Modern variators use electroniccontrol system, whose main function is to change the diameters of the pulleys in accordance with how a change in the engine's performance occurs. The task of the electrician is also the control of the clutch and the planetary gearbox.
If you are interested in the question, what is different aboutvariator from the machine, then we can say that there is no difference between cars with such gearboxes. There are two pedals, as well as a selector switch. But in the case of a variator there are no usual fixed transmissions, as well as decelerations and shocks associated with their switching. This kind of gearbox smoothly and confidently disperses the car, and jerking and jerking are completely eliminated. Modern manufacturers have got rid of this problem by introducing the possibility of choosing from a certain number of fixed gear ratios. It is made specially for imitation of classical transfers.
Now you know what a variator is.</ p>>