What is gear box , type of gear box used by automobile ,what is transmission system of automobiles

WHAT IS GEAR BOX

In this article we will discuss about types of gearbox used in transmission system of automobiles.

An automobile needs high torque while climbing on hills and when starting,
Even though they are performed at low speeds. On other hand, when running at high speeds on flat roads, high torque is not required because of momentum. 
So we needed of a equipment which can change the vehicle’s torque and speed according to road condition or when the driver needed.
and that equipment is known as gearbox box.

In an automobile various gearboxes are used which allow the vehicle to obtain different torque and speed combination. These are as follows

Classification of Gearbox:

Primerly Gear box is divided into two types according to the transmission. These are:-

✓ Manual transmission gearbox

✓ Automatic transmission gearbox
 

 Automatic transmission gear lever

Manual transmission gear lever

1. Manual Transmission Gearbox:

In this transmission different speed ratio (gear ratio) is selected by the driver manually. 
special skill of driving is needed to operate this type of gear box. According to their design, manual transmission gear box is subdivided into three types:-

(A.) Sliding mesh gear box:

In this, gears on the main shaft are moved right or left for meshing them with right gears on the counter shaft for get different speed.
This type of gear box gears are meshed by sliding.
disadvantage
special skill is needed to operate this gear box
High chances of wear and tear of this gearbox.

Images

(B.) Constant mesh gear box:

In this gearbox, all the gears are in constant meshed with each other all time
The gears of the main shaft rotates freely without rotating the main shaft. Constant mesh gear box have two dog clutches.
These clutches are attached on the main shaft, one between the clutch gear and the second gear and the other between the first gear and reverse gear.
So in this type of gear box (constant mesh gear box) we can change the gear ratio by shifting the dog clutch. This type of gear box is more popular than sliding mesh because it creates low noise and less wear of gears.

(C.) Synchromesh gear box:

problem  in constant mesh gear box is that when the driver engage the dog clutch, the main shaft and gear to be meshed which are running at different speed. So when engage this action cause gear wear and tear of dog clutch. This problem is solved by  synchromesh gear box. This gear box is as same as the constant mesh gear box
In this dog clutch is replaced by synchromesh devices.

Synchromesh

Synchromesh gear equipment works on the principle
That before engaging two gears are to be first brought into frictional contact which equals their speed after which they engaged smoothly.
This Synchromesh gear box is widely used in automobile.

2. Automatic Transmission Gear box:

A transmission in which various speeds ratio are obtained automatically is known as automatic transmission. In this type of gear box driver selects the general car condition such as forward or reverse. The selection and engagement of gear for the required gear speed are done automatically when the accelerator is pressed or depressed. Automatic transmission needs no gear change lever and clutch pedal because clutch and transmission is a combined in one unit and works automatically.

Automatic transmission is generally subdivided into two types:

(A.)  Epicyclic gear box:

(B.)  Torque converter:

(C.)  AMT

(D.)  CVT 

(E.).  DTC

In this article we have discussed main types of Gear box used by automobile.

        Team mechanic adda