Torque Coverter || Transmission System

Introduction

The Torque convertor, as the name suggests of something related to ‘’Torque’’, which is defined a s a force that tries to rotate an object, and ‘’Convertor’’ suggest some sort of conversion taking place.

Torque Convertor is a part of a transmission system and is usually employed where the conventional clutch system is eliminated.

Now, being a component/part of a transmission system, often employed in an Automatic type of a transmission system.

As the main or the primary function for any transmission system is the Torque multiplication, hence torque convertor is also responsible for the torque multiplication.

So, the torque convertor is a fluid coupling, that transfers the rotating power from the main source, here the main source is the internal combustion engine to a driven rotating load.

Due to the absence of the gears sets, the fluid inside the torque convertor is always as the work, but as during the idling the torque generated by the fluid coupling inside the torque convertor, input from the internal combustion engine rpm is quite low to produce enough torque so that the vehicle is able to move.

Thus, the vehicle remains stationary during the idling.

As the rpm of the main source is increased, the torque force inside the torque convertor generating the torque is also increased thus the vehicle moves forward.

Now, as we have made a brief understanding on how is this whole mechanism working, we shall discuss on the various components of the torque convertor.

Components of a Torque Convertor

• Impellor/Pump
• Turbine
• Stator
• Fluid
• Lock-up Clutch

Impellor/Pump

The impellor is nothing but a set of circular arrangement of the fins attached to the housing of the torque convertor that in turn is attached to the flywheel of the engine so that all these components rotates at the very same speed as of the engine.

The rotation of these fins allows the fluid to be thrown in an outwards direction due to the principle of the centrifugal force , creating a vacuum at the very center, thus allowing more fluid.

The cycle keeps on going this way.

Turbine

The fluid from outside then enters the turbine through its curved blades.

The turbine is directly attached to the transmission line which drives the vehicle and is free to rotate at any speed.

The fluid enters the curved blades of the turbine thus undergoing a directional change and exerts the pressure that rotates the turbine and hence the vehicle.

Stator

The working of a stator is quite interesting. Now as we know the fluid passing from the turbine undergoes a directional change, if this fluid is allowed to directly hit the impellor/pump, it would rather slow down the speed of the impellor/pump and thus we need a mechanism to further change the direction of this fluid in the same direction of the impellor/pump.

The stator is attached with one way clutch with a fixed shaft to allow it to spin in only 1 direction, that is of the impellor/pump.

The blades of the stator are very sophisticatedly design for the efficient effectiveness.

Fluid

The whole game is of the fluid in the torque multiplication process.

Lock-up Clutch

This system locks up the impellor and the turbine at the higher speed so that they collectively move in the same direction for the efficient working of the system.

When the speed is reduced, the conventional fluid coupling system resumes.

Advantages

Allows the car to start and stop without changing gears manually.

The vehicle can accelerate much faster and smoother than a conventional clutch system.

Due to its heaviness, it acts as a flywheel thus absorbing the jerks for smooth operations.

This system slips without any damage, while clutch system burns up the clutch plates.

It is a fluid mechanism, thus greatly reduces the overheating od the components.

Disadvantages

Torque converters often fail due to leakage or bad transmission fluid,

Shuddering may also be the issue, contributing to a bad torque converter.

A very Trained mechanic is needed to diagnose the issue.

Originally published at https://www.carengineered.com on September 28, 2020.