WEBVTT

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Some technologies are easier to understand

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with the help of 3D animation

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But, What about the 6-Speed Automatic transmition from Allison

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To visualize and understand

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This beautiful planetary gearset mechanism

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A 2D Animation will be ideal

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You can consider this 2D drawing as a cross section of the 3D model

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A planetary gearset has 2 inputs and 1 output

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If you properly understand working of a planetary gearset

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You can easily understand automatic transmitions from the 2D animation

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the essence of the planetary gearset is
that just by giving

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different speeds to the ring and sun
gears you will be able to get different

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speeds at the output

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the beauty of automatic transmissions
lies in how these different input speeds

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are transmitted

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let's see it in the 2D animation

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this 3D planetary set is represented in 2D as shown

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in an automatic transmission the input
and the output are not directly

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connected they are connected through an
intermediate shaft as shown

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now a small suggestion before you
proceed you will be able to explain all

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seven gears by yourself by pausing the
video for a moment and understanding the mechanism

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please try that at every single gear you
will be amazed by the brilliance of this mechanism

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if you press clutch see one the input
will be connected to the sun gear if you

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press clutch C5 the output rain gear
will be stationary

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this will result in the first gear

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now let's add one more gear set here
comes the tricky part

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the carrier of this set is connected to
the ring gear of the first set

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this simply means that the output of the
second set is connected to the input of the first set

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think for a moment about what happens
when you apply C1 and C4

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Since C4 is applied the ring gear of
the second set will be stationary

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this makes the carrier turn this carrier
is connected to the ring gear of the first set

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so the ring gear of the first set will
also turn

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this in turn will increase the output speed

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or we will get the second
gear

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to obtain a fourth gear or direct drive
a rotating clutch module is also used

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we know that for a direct drive both the
Sun and the ring gear should rotate at

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the input speed

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if we press C2 and C1 together

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this is what happens

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in the very same mechanism if you apply
C2 and C4 you will get very high speed

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at the output think for a moment and try
to understand this

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it is clear that the carrier of the
second set will turn at the input speed

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however here the ring gear is stationary

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this makes the sun gear

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turn at almost three times the
speed of the input

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eventually a very high output speed is
obtained

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one more gear set is used to obtain the
remaining gear ratios

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however the sun gear of this set is not
connected to the shaft

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instead it is connected to the rotating
clutch module

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so this sun gear will always turn at the
input speed

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and here again the output of

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the set is connected to the input of the
adjacent set

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for the remaining gear ratios C3 is
always applied this means that the brown

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carrier or ring gear of the second set
will turn at one-third of the input

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speed for the remaining cases

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for the third gear apply see one as well

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for the fifth gear apply C2 along with C3

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the reverse is an interesting mechanism

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here C5 is applied along with C3

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so here the carrier of the second set is
stationary

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this means that the planet gears of this
set will not be able to revolve

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and that they will simply spin

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this spin is in the same direction as
the input this planetary spin will make

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the corresponding sun gear spin in the
opposite direction as a result

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the output sun gear will also turn in the
opposite direction and we will get

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the tereverse gear

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we hope that you enjoyed the brilliance
of the allison transmission mechanism to

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make our free educational services
sustainable

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please support us at patreon.com thank
you