Introduction

Automatic transmissions are hydraulically operated control systems, they are managed electronically by the vehicle’s computer. This type of transmission is totally different from the manual transmission because the gears are selected automatically and smoothly. This transmission is easy to operate, all the driver has to do is to understand Park (P), Neutral (N) and Drive (D). After that, the rest job is done itself.

How Automatic transmissions system works

In Automatic transmission, gears are selected automatically, as recently mentioned due to provided necessary conditions including engine speed, vehicle speed, performance mode which is selected as well as the driver assist system such as stability control, traction control, cruise control and automatic or autonomous braking.

In older automatic transmissions, the shifting action was accomplished by internal fluid pressures overcoming spring tension – closing one circuit before opening another. This control system produced harsh, jerky shifting. Modern systems moderate the action of the controlling valve shuttles, providing almost seamless shifting.

The pressurized transmission fluid is automatically channeled to mechanisms that drive the clutches and sets of planetary gears due to the agreement between the Engine Management and Transmission Control Systems.

Torque is transferred from the engine to the transmission tanks to the shearing strength of fluid.
Torque converter provide rotational energy. the mechanism consists of two freely rotating parts. Half of it is attached to the engine and the other to the transmission input shaft. The two halves of the converter are placed very close to each other. The fluid that circulates between them is influenced by the rotational energy of the engine which in turn impacts the transmission side of the converter.

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