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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[br]that just by giving

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different speeds to the ring and sun[br]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[br]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[br]and the output are not directly

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connected they are connected through an[br]intermediate shaft as shown

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

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

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

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

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press clutch C5 the output rain gear[br]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[br]comes the tricky part

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the carrier of this set is connected to[br]the ring gear of the first set

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

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

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

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

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so the ring gear of the first set will[br]also turn

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this in turn will increase the output speed

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or we will get the second[br]gear

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

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we know that for a direct drive both the[br]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[br]C2 and C4 you will get very high speed

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

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it is clear that the carrier of the[br]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[br]speed of the input

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eventually a very high output speed is[br]obtained

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one more gear set is used to obtain the[br]remaining gear ratios

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

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instead it is connected to the rotating[br]clutch module

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so this sun gear will always turn at the[br]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[br]adjacent set

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

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carrier or ring gear of the second set[br]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[br]stationary

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this means that the planet gears of this[br]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[br]the input this planetary spin will make

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the corresponding sun gear spin in the[br]opposite direction as a result

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

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the tereverse gear

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

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make our free educational services[br]sustainable

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please support us at patreon.com thank[br]you