Planetary Gear Trains
The 8 forward gears and the reverse gear are produced by a combination of 4 simple planetary gear sets, 3 clutches and 2 brakes. The front 2 gear sets share a common sun gear. Power is output always through the planetary carrier of the fourth gearset.
5 shift elements comprising 3 clutches and 2 brakes, are responsible for all 8 forward and reverse gears. High efficiency is achieved by the use of only 2 shift elements disengaged in each gear which reduces drag and so increases the efficiency.
Planetary Gear Set 1
The planetary gear sets 1 comprises:
- Sunwheel
- 4 planetary gears
- Planetary gear carrier (spider)
- Ring gear.
Planetary Gear Sets 2 and 3
The planetary gear sets 2 and 3 comprise:
- Sunwheel - shared by both gear sets
- 3 planetary gears per gear set
- Planetary gear carrier (spider) per gear set
- Ring gear per gear set.
| ITEM | DESCRIPTION |
|---|---|
| 1 | Planetary gears - gear set 1 |
| 2 | Ring gear - gear set 1 |
| 3 | Planetary gear carrier (spider) |
| 4 | Planetary gears - gear set 2 |
| 5 | Ring gear - gear set 2 |
| 6 | Planetary gears - gear set 3 |
| 7 | Ring gear - gear set 3 |
| 8 | Sun wheel - gear set 3 |
| 9 | Sun wheel - joint gear sets 1 and 2 |
Planetary Gear Set 4
The planetary gear set 4 comprises:
- Sunwheel
- 4 planetary gears
- Planetary gear carrier (spider) - output shaft
- Ring gear.
| ITEM | DESCRIPTION |
|---|---|
| 1 | Ring gear |
| 2 | Planetary gears |
| 3 | Output shaft/gear carrier |
| 4 | Sun wheel |