Planetary Gear Trains
WARNING: This page is about a different car, the 2019 Jaguar XJ and 2018 Jaguar XJ. However, it is still accessible from the selected car via links, so may be relevant.
The 8 forward gears and the reverse gear are produced by a combination of four simple planetary gear sets, 3 clutches and 2 brakes. The front two gear sets share a common sun gear. Power is output always through the planetary carrier of the fourth gearset.
Five 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 Sets 1, 2 and 3
The planetary gear sets 1 and 2 comprise:
- Sunwheel - shared by both gear sets
- 4 planetary gears per gear set
- Planetary gear carrier (spider) per gear set
- Ring gear per gear set.
The planetary gear set 3 comprises:
- Sunwheel
- 3 planetary gears
- Planetary gear carrier (spider)
- Ring gear.
| 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 | Sun wheel |
| 4 | Output flange |