The clutch block and gearbox are used for smooth starting and changing the gear ratio between the engine and the axle of the driving wheels. There are two main types of gearboxes - mechanical and automatic, as well as many subspecies. But the most demanded and popular is mechanical.
What happens if you remove the clutch with the gearbox from the car and direct the torque from the engine crankshaft directly to the wheels? Firstly, it will not be possible to achieve a smooth start-off. As soon as you start the engine, the car will start immediately. Secondly, under high loads (for example, when starting up a hill), it will not be possible to start moving. So, we can conclude that the clutch is necessary to separate the engine and transmission. The latter is used in the design to change the torque.
There are several types of gearboxes:
- mechanical, which is controlled by the driver, the choice of the gear ratio depends on him;
- automatic, the gear change in which depends on the engine speed, load, as well as a number of other factors.
But the most common is mechanical. Its main plus is that the driver independently chooses the gear ratio. A very useful quality when driving off-road, snow, ice. And towing a car with such a box is allowed at any distance and at any speed (just take into account the restrictions and requirements of traffic rules).
Manual gearbox
The most common, simple and reliable gearbox design. Its inconvenience is that it is necessary to switch gears independently when changing the speed of movement. Moving through many kilometers of traffic jams, the body is very tired from the frequent squeezing of the clutch. With this type of movement, the life of the clutch block is also reduced.
The design is simple, only two shafts - primary (connected by a clutch disc to the engine crankshaft) and secondary (connected to a gearbox mounted on the drive axle). The most widespread are mechanical transmissions, which have 4 and 5 operating modes (not including reverse, reverse). For a four-speed gearbox, the highest fourth speed has a gear ratio of 1: 1, and all others are greater than one.
As for the fifth speed, its gear ratio is slightly less than one. In the early stages of the development of the automotive industry, many boxes were supplemented with a separate step-up block, which was turned on when a certain speed was reached. And when the speed dropped, this unit was turned off. Of course, not in all cars it was the fifth speed, in some it was both the third and the fourth, depending on the design features of the standard gearbox.
In most modern cars, all gears are synchronized, which allows you to turn on any speed without performing "clever" manipulations. If there are no synchronizers, then the input and output shafts move asynchronously. To make a gear change, you need to squeeze the clutch, set the lever to neutral, release and depress the clutch again, turn on the desired speed. Synchronizers eliminate this complexity and make driving much easier.
