Torque Converter

Introduction

Torque converter is a counterpart of clutch in an automatic transmission. A torque converter is a type of fluid coupling which allows the engine to spin somewhat independently of the transmission. Torque converter is basically the replacement of the clutch system.

Working

Four major components of torque converter are:

ü  Pump

ü  Turbine

ü  Stator

ü  Transmission Fluid

The housing of the torque converter is rushed to the flywheel of the motor, so it turns at whatever speed the motor is running at. The pump inside a torque converter is a sort of diffusive pump. As liquid is dive to the outside, a vacuum is made, that attracts more liquid on the inside.

The liquid then enters the sharp edges of the turbine, which is associated with the transmission to the turn which really moves the wheels. The liquid leaves the turbine at the middle, moving in an unexpected course in comparison to when it entered. The liquid leaving the turbine moves inverse to the course of

                                                           Figure 3: Working with Torque Converter

pump and engine. So this fluid must not be allowed to hit the pump again. This is why a torque converter has a stator.

The stator can be found in the center of the torque converter. Its job is to redirect the fluid returning from turbine before it hits the pump again.

Around 40mph(64 kph), at which both pump and turbine are spinning at almost same speed, the fluid returns from the turbine, entering the pump, already moving in the same direction as the pump, so the stator is not needed.

Advantages

Use of torque converter is very advantageous in the power transmission of an engine. Some of its advantages are listed below:

Ø  Convenience:

Torque converters allow a car to start and stop minus user intervention. It is this piece that makes an automatic truly "automatic" and the main reason that torque converters are used.

Ø  Torque Multiplication:

In the moments before full engagement, torque converters act as a sort of continuously variable transmission. This torque increase means that a vehicle so equipped can accelerate faster and smoother than one with a clutch.

Ø  Flywheel Effect:

                            Because torque converters are very heavy, they tend to act as a sort of inertial flywheel. This flywheel outcome means that vehicles with torque converters have a firmer idle and smoother operation than clutch cars.

Ø  Infinite Slippage:

     To a point, a torque converter can slip almost indefinitely minus damage. This relates sharply with a manual transmission's tendency to burn clutches if permitted to slip too much.

Ø  Fluid Reservoir:

 Torque converters hold several quarts of transmission fluid and can help to decrease transmission overheating by providing a source of cool fluid when required.