Transmission as one of most essential part in a vehicle, which serve as control movement of the vehicle. It uses the power created by the engine and allow the wheels to move and stay on stationary position, It also keeps the engine within a certain revolutions per minute range.

A transmission system refers to the mechanism that transmits the power developed by the engine to the wheels of an automobile in the form of kinetic energy. These transmission parts are toothed wheels that comprises of interlinked set of rotating gears which are basically used for changing speed or direction of a moving vehicle.
The expression of ‘transmission’ in an automobile engine refers to the gearbox. For covering smaller distances there are low gears and for larger distances there are high gears. High gears usually have more number of teeth and have an ability of covering larger distances in just one revolution of pedal.

The arrangement of the transmission and where it sits is dependent on whether the car is all-wheel drive, front-wheel drive, or rear-wheel drive. basically, transmission system comprises of various transmission components such as gears, shafts and other parts, which function together to enable the movement of a vehicle.

In addition, the engines typically operate over a range of 600 to about 7000 rpm (though this varies, and is typically less for diesel engines), while the car’s wheels rotate between 0 rpm and around 1800 rpm and provides its highest torque and power outputs unevenly across the rev range resulting in a torque band and a power band.

Type of Transmission System

Basically, there are two types of transmission system used in a vehicle. they are, Manual and Fully Automatic transmission. well, the game is changing why because modern car transmission system are called, Semi-Automatic transmission and Continuously Variable Transmissions (CVT), their primary purpose is that, they are easier to use than ever before. however, the manual and fully automatic transmission system can’t be avoided due to the modern transmissions of all types have become more prone to failure, primarily because of this higher level of complexity.
In this article, you’ll get to know and have basic understanding on all types of transmission system listed below:

1. Manual Transmissions: This is the oldest type of transmission system, but still used till date due to it effectiveness. As the name suggests, the selection of gear ratios on manual transmissions is accomplished by manually shifting a gear selector mechanism that disengages one gear and selects another.
Manual transmission is connected to the engine with used of a clutch, which is always on engaged position, power is delivered to the transmission through an input shaft that is separated from the primary cluster, and which can rotate at a different speed to the cluster. But if disengaged (by pressing the foot pedal or hand lever), it removes torque from the system.

2. Fully Automatic Transmissions: This type of transmission is hydraulically operated control systems. Clutch and gear stick has became useless, because they are managed electronically by the vehicle’s computer. In this transmission no stress for the driver, all the driver has to do is shift the selector from Park (P) or Neutral (N), into Drive (D), and the gear shifting will take place automatically and smoothly, without any additional input from the driver under normal driving conditions.

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3. Semi-Automatic Transmissions: This type of transmission is known as an “automatic manual” or “clutchless manual” transmission. The transmission tries to combine the advantages of the manual and automatic transmission systems, but avoid their disadvantages and it can be describe as hybrid between a fully automatic and manual transmission.
There is no need of clutch pedal in this transmission system, the gears are change via a simple shifter or paddle located behind the steering wheel. Using the gears automatically, the processors, sensors, pneumatics and actuators are all used to shift the gears once the drive has signalled the change.
The basic principles of shifting mechanical gears in a semi-automatic fashion have been in use on heavy commercial vehicles for many years. The latest and best designs provide lightning-fast, almost undetectable gearshifts.

4. Continuously Variable Transmissions (CVT): this transmission doesn’t use gears as its means of producing various vehicle speeds at different engine speeds. Instead of gears, the system relies on a rubber or metal belt running over pulleys that can vary their effective diameters. To keep the belt at its optimum tension, one pulley will increase its effective diameter, while the other decreases its effective diameter by exactly the same amount. This action is exactly analogous to the effect produced when gears of different diameters are engaged.

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How Transmission System Works

At first, the engine produces some power in expansion stroke, it called as indicated power. this power is fed into crankshaft and tends to rotate by pushing the piston downward. The power that comes through a crankshaft is called, brake power. Hence the downward movement of piston tends to rotate crankshaft and it produces some torque.

The power from the engine is passed into gearbox. In a transmission system consists of clutch and gearbox. The gearbox can be manually or automatically operated. The function of gearbox is used to vary the speed of vehicle from the engine as per we required and mainly depends upon road conditions.

Here the clutch plays an important role. The function of clutch is used to engage and disengage the transmission shaft (gearbox shaft) to engine. It can be operated by an lever in driver compartment. Always clutch is in engage position hence power can be transmitted from engine to gearbox, then pressing a lever it would became disengaged, hence there is no power transmission from engine. This stage is called engine idling. Finally the power from the gearbox is passed through the differential by propeller shaft. The propeller shaft is connection between drive and driven shaft. The Differential would split the power to wheels as per our positioning of vehicle. At last vehicle can be propelled.

Also check: Operation of Transmission system