What is CPR

Many may be interested in the question of what a checkpoint is? So, if you say dry language, the transmission is designed to change the torque, which is transmitted to the drive wheels from the crankshaft. And if you look from the point of view of a beginner to the question of what a check point is, and why to switch gears, then a lot of difficulties arise. Shifting is a necessity that arises because the engine torque is not uniform. You can compare the engine with an electric motor.

The main difference between them from the point of view of interest to us are the traction characteristics, that is, how, depending on the speed of power, the torque changes. The electric motor has a significant torque at low revs. The indicator falls as you unwind. This characteristic is most favorable for the machine during the start from the place and the subsequent acceleration, when it is necessary to overcome a large inertia force, it is at this time that it is best to have as much torque as possible. Uniform movement requires a much smaller torque to maintain it. At any speed, the power of the electric motor can remain practically maximum, and it can be used almost completely in all modes, that is, it is perfectly adapted to road conditions.

If we talk about the internal combustion engine, then everything is completely different, with reduced speed, its power is significantly reduced, and the magnitude of the moment varies little within the limits of operational numbers. Traction characteristics of such an engine can hardly be called satisfactory. However, for the remaining indicators, the power plant with such a motor is noticeably superior to an electric motor. Since the designers were forced to put up with such shortcomings, the car was equipped with a gearbox to overcome them. So, what is a CAT? It is designed to change the ratio that is present between the engine and the main wheels.

Understanding the issue of "CAT - what is this?" Is to say that different in value torque can be obtained through the use of gears of different sizes. If you place the intermediate gear between the slave and the master, you get a change in the direction of rotation of the slave, which gives us a reverse gear. It turns out that any CAT: automatic, robot, variator or mechanical serves to provide the most optimal mode of the engine in different conditions by changing the same ratio.

Any gearbox has lower and higher stages. When starting from a place, acceleration, subsequent movement at low speed or off-road, you need the highest torque achievable at medium-high speed, however, there is no need to develop high speed. Movement in this mode is provided by the lower gear stages in the gearbox, which have a small gear ratio, which means that even at high engine speeds, the car will move slowly.

Uniform movement at high speed can be ensured only in the case of a high speed of the wheels, as well as maintaining the engine speed at the optimum range. This is possible due to higher gears, which have smaller gear ratios. The car will go at a similar engine speed much faster, until it reaches the maximum speed. However, in the higher gear, the car can not move at a low speed, and also move away from the place, since the torque required for the propulsion will not be developed, and the car itself stalls. So, you should understand what a checkpoint is, and what it's needed for in a car.