Automatic Transmission

Flow Diagram

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Power Flow Diagram

P, N UD/B LR/B 26/B 35R/S OP/K OWC
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Rotation Direction: Low and Reverse Brake (LR/B) Activation > Overdrive (O/D) Hub Lock > Center and Rear Planetary Carrier Lock. Input Shaft Rotation > Rear Sun Gear Rotation > Rear Internal Gear Rotation (Reverse) > Rear External Gear Rotation > Rear Ring Gear Rotation > Front Ring Gear Rotation > Front Gear Rotation > Front Sun Gear Rotation (Reverse) > Underdrive (U/D) Hub Rotation (Ensures Regression). Input Shaft Rotation > Overdrive Clutch (OD/C) Stopper Rotation. Input Shaft Rotation > 35R Clutch Rotation
R UD/B LR/B 26/B 35R/S OP/K OWC
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Power Delivery Route: Center planetary carrier locked, center sun gear rotates. Rotation of the center planetary sun gear while the carrier is fixed in place slows and rotates the ring gear in reverse (front carrier), transmitting power to the front carrier. The rear and front ring gears of the rear planetary gear rotate at reduced speed, resulting in reverse rotation without load on the front sun gear of the front planetary gear.
D1 UD/B LR/B 26/B 35R/S OP/K OWC
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Power Flow Path — Front sun gear, center and rear carriers are locked, and the rear sun gear rotates continuously. When the rear sun gear rotates, power is reduced by the rear planetary gear set and then delivered to the rear and front ring gears. Power is reduced again by the front planetary gear set, whose sun gear is held stationary, and then delivered to the front carrier. Here, the center ring gear, which is integrated with the front carrier, rotates and causes reverse rotation; the center sun gear rotates at zero load.
D2 UD/B LR/B 26/B 35R/S OP/K OWC
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Power Flow Path — Front sun gear and center sun gear are locked, and the rear sun gear rotates continuously. Rotation of the rear sun gear transmits power to the rear carrier and front ring gear, and the reaction from the front carrier and center ring gear, to which the sun gear is attached, transfers to the center and rear carriers, resulting in power balance and power transmission to the front carrier.
D3 UD/B LR/B 26/B 35R/S OP/K OWC
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Power Flow Path — Front sun gear is locked, and the center and rear sun gears rotate. Rotation of the center sun gear and rear sun gear transmits power to the rear and front ring gears, and the reaction from the front carrier and center ring gear, to which the sun gear is attached, transfers to the center and rear carriers, resulting in power balance and power transmission to the front carrier.
D4 UD/B LR/B 26/B 35R/S OP/K OWC
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Power Flow Path — Front sun gear is locked, and the rear carrier and rear sun gear rotate. Activation of the overdrive clutch (OD/C) locks the rear planetary carrier and sun gears together. The 1:1 rotation ratio passes through the rear and front ring gears and reaches the front carrier, to which the front planetary sun gear is attached. Here, the center sun gear of the center planetary gear set rotates at a higher speed in the normal direction and at zero load due to the reduced ring gear and carrier action with a 1:1 rotation ratio.
D5 UD/B LR/B 26/B 35R/S OP/K OWC
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Power Flow Path — Center and rear carriers, center sun gear and rear sun gear are rotating. The center carrier and center planetary sun gear rotate simultaneously, resulting in a 1:1 rotation ratio transmitted to the center ring gear (front carrier). Here, the rear planetary gear set rotates at a 1:1 gear ratio, as in 4th gear engagement; however, the front planetary gear set remains unlocked, and the front sun gear rotates in the normal direction at zero load and a 1:1 gear ratio.
D6 UD/B LR/B 26/B 35R/S OP/K OWC
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Power Flow Path — Center carrier rotates, center sun gear is locked. When the center planetary sun gear is locked in place and the center carrier is allowed to rotate, the center ring gear increases rotational speed and transmits power to the front carrier. Here, the rear planetary gear set maintains a 1:1 gear ratio, as in 4th or 5th gear engagement; however, the front planetary gear set remains unlocked, and the front sun gear rotates at a higher speed in the normal direction and at zero load.

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