Power Flow

POWER FLOW





1. "D" OR "2" RANGE FIRST GEAR
Operating Clutches, Brakes and Solenoid Valves
Forward clutch
Coast clutch
One-way clutch No. 1
Solenoid Valve No. 1
The engine power from the input shaft is transmitted to the rear planetary ring gear through function of the coast clutch and one-way clutch No. 0. In other words, the rear planetary ring gear turns clockwise at the same speed as the input shaft owing to operation of the forward clutch, coast clutch and one-way clutch No. 0.
The rear planetary ring gear, as it turns, causes the rear planetary pinion to rotate on its own axis clockwise while turning around the rear planetary sun gear clockwise and the rear planetary sun gear to turn counterclockwise. On the other hand, with the front planetary ring gear prevented from turning counterclockwise by function of the one-way clutch No. 1, the front planetary sun gear, which is incorporated with the rear planetary sun gear, rotates on its axis at such speed of the specified ratio to that of the front planetary pinions, which are linked with the rear planetary pinion through the planetary carrier and turning around at the same speed. In other words, the ratio of the revolution speed between the sun gears and planetary carrier is determined by the front planetary gears set. Previously described revolution of the rear planetary ring gear is transmitted to the rear planetary pinions (rear planetary carrier) and the rear sun gear at this speed ratio. As the planetary carrier is incorporated with the counter drive gear, the counter drive gear also turns clockwise.
When attempting to use the engine brake (when the counter drive gear tries to turn faster), the one-way clutch No. 1 operates to cause the front planetary ring gear to turn clockwise. Then, revolution of the planetary carrier is released and the engine brake does not work.





2. "D" OR "2" RANGE SECOND GEAR
Operating Clutches, Brakes and Solenoid Valves
Forward clutch
Coast clutch
2nd/4th brake
Solenoid valve No. 1
Solenoid valve No. 2
Just like the 1st gear, the engine power from the input shaft is transmitted to the rear planetary ring gear through function of the forward clutch, coast clutch and one-way clutch No. 0. On the other hand, as the sun gears are prevented from turning by the 2nd/4th brake, revolution of the rear planetary ring gear turning clockwise at the same speed as the input shaft, causes the rear planetary pinion to rotate clockwise on its own axis and at the same time turn around the rear planetary sun gear clockwise. As the rear planetary pinion is installed to the planetary carrier and linked with the counter drive gear, the counter drive gear also turn clockwise at the same speed as the rear planetary pinion turning on its orbit.





3. "D" RANGE THIRD GEAR
Operating Clutches, Brakes and Solenoid Valves
Forward clutch
Coast clutch
Overdrive clutch
Solenoid valve No. 2
TCC control solenoid valve (At TCC operates.)
The engine power from the input shaft is transmitted to the rear planetary ring gear and the front planetary ring gear through function of the forward clutch, coast clutch, one-way clutch No. 0 and overdrive clutch. In other words, the rear planetary ring gear and the front planetary ring gear, together with the input shaft as one unit, turns clockwise at the same speed. At this time, the front and rear planetary ring gears independently try to turn the front and rear planetary pinions and planetary sun gears which are engaged with them respectively. However, the front and rear planetary sun gears are incorporated and the front and rear planetary pinions are prevented from turning independently by the planetary carrier. As a result, with the front and rear ring gears, planetary pinions and planetary sun gears double engaged, planetary gears turn as one unit, clockwise and at the same speed as the input shaft. For this reason, the counter drive shaft connected to the planetary carrier also turns clockwise at the same speed.





4. "D" RANGE 4TH GEAR
Operating Clutches, Brakes and Solenoid Valves
Forward clutch
Overdrive clutch
2nd/4th brake
TCC control solenoid valve
The engine power from the input shaft is transmitted to the front planetary ring gear through function of the forward clutch and overdrive clutch. In other words, the front planetary ring gear turns clockwise at the same speed as the input shaft.
On the other hand, as the 2nd/4th brake functions to stop the planetary sun gears from turning, revolution of the front planetary ring gear causes the small planetary pinions to turn counter clockwise on their own axes and the large planetary pinion to turn clockwise on its own axis while causing these planetary pinions to turn around the front planetary sun gear clockwise. As a result, the planetary carrier turns clockwise and so does the counter drive gear.





5. "L" RANGE
Operating Clutches, Brakes and Solenoid Valves
Forward clutch
Coast clutch
1st/Reverse brake
Solenoid valve No. 1
The power train is the same as that of "D" or "2" range 1st gear but it is so designed that the 1st/reverse brake operates to prevent the front planetary ring gear from turning clockwise and resulting in engine brake failure, when the engine brake is used.





6. "R" RANGE
Operating Clutches, Brakes and Solenoid Valves
Reverse clutch
1st/Reverse brake
Coast clutch
Solenoid valve No. 1
The engine power from the input shaft is transmitted to the planetary sun gears through function of the reverse clutch. Thus, the planetary sun gears, together with the input shaft as one unit, turn clockwise at the same speed. On the other hand, as the 1st/reverse brake functions to prevent the front planetary ring gear from turning, revolution of the front planetary sun gear causes the large planetary pinion to rotate counterclockwise on its own axis, and the small planetary pinion to rotate clockwise on its own axis, while causing their planetary pinions to turn around the front planetary sun gear counterclockwise. As a result, the planetary carrier turns counterclockwise and so does the counter drive gear.





7. "P" OR "N" RANGE
Operating Clutches, Brakes and Solenoid Valves
Coast clutch
Solenoid valve No. 1
The engine power from the input shaft is not transmitted any further because the forward clutch and reverse clutch are not operating.
If the gear is still in the "P" range, the parking lock pawl is meshed with the parking lock gear on the counter driven gear and keeps the vehicle at a stop.