Torque converter is a hydraulic transmission
which increases the
torque of the vehicle reducing its speed . It provides a continuous variation
of ratio
from low to high. The key characteristic of a torque converter is its ability
to multiply
torque when there is a substantial difference between input and output rotational
speed, thus providing the equivalent of a reduction gear. cars with an
automatic transmission have no clutch that disconnects the transmission from the
engine. So, they use an amazing device called a torque converter.
What’s
Inside The Torque Converter?
There
are four components inside the very strong housing of the torque converter:
·
Pump
·
Turbine
·
Stator
· Transmission
fluid
These
are the parts in the figure turbine,stator,pump , The
housing of the torque converter is bolted to the flywheel of the engine, so it
turns at whatever speed the engine is running at. The pump inside a torque
converter is a type of centrifugal pump. As it spins, fluid is flung to the
outside. As fluid is flung to the outside, a vacuum is created that draws more
fluid in at the center. The fluid then enters the blades of the turbine, which
is connected to the transmission. The turbine causes the transmission to spin, which
basically moves your car. The blades of the turbine are curved. This means that
the fluid, which enters the turbine from the outside, has to change direction
before it exits the center of the turbine. It is this directional change that
causes the turbine to spin.
In
order to change the direction of a moving object, you must apply a force to
that object -- it doesn't matter if the object is a car or a drop of fluid. And
whatever applies the force that causes the object to turn must also feel that
force, but in the opposite direction.
So
as the turbine causes the fluid to change direction, the fluid causes the
turbine to spin. The fluid exits the turbine at the center, moving in a
different direction than when it entered. The fluid exits the turbine moving
opposite the direction that the pump (and engine) are turning. If the fluid
were allowed to hit the pump, it would slow the engine down, wasting power.
This is why a torque converter has a
stator. The stator resides in
the very center of the torque converter. Its job is to redirect the fluid
returning from the turbine before it hits the pump again. This dramatically
increases the efficiency of the torque converter. The stator has a very
aggressive blade design that almost completely reverses the direction of the
fluid. A one-way clutch (inside the stator) connects the stator to a fixed
shaft in the transmission (the direction that the clutch allows the stator to
spin is noted in the figure above). Because of this arrangement, the stator
cannot spin with the fluid -- it can spin only in the opposite direction,
forcing these fluid to change direction as it hits the stator blades. The
figure (top to bottom) shows the pump, turbine and the stator, sending the fluid
in their respective direction.
