Power Flow. Different Gear Positions

Power flow. Different gear positions

Position P (Park)

Primary shaft (P1, P2):
The input shaft rotates clockwise. All clutches and brakes are disengaged, and no power is transferred to the planetary trains.
Secondary shaft (P3):
No power is transmitted to the secondary shaft. B4 locks the sun gear so that it cannot rotate in any direction. Shift-lock (P) is disengaged. The planetary gears can rotate freely around the sun gear, and the car can start to roll if parked on an incline.
Brake B4 is activated in both P and N in order to minimize engagement impact. Otherwise this occurs when several brakes and clutches are activated simultaneously, when the gear selector is moved to position D or R. Because B4 is also applied in both 1st gear and reverse, the number of simultaneous engagements is reduced.

Positions D and 3 - 1st gear

Primary shaft (P1, P2):
The input shaft rotates clockwise and C1 connects the input shaft with the rear planetary train (P1) ring gear so that it rotates clockwise at the input shaft rpm. The inner planetary gears in P1 rotate clockwise. (The sun gear shaft rotates counter-clockwise.)
F2 prevents the front planetary train ring gear from rotating counter-clockwise. The outer planetary gears in P2 rotate counter-clockwise and at the same time move clockwise around the inner planetary gears. The planetary gear carrier and the driving intermediate gear rotate clockwise as a unit at lower speed than the input shaft.
Secondary shaft (P3):
Because the driving intermediate gear rotates clockwise, the driven intermediate gear and P3 ring gear are driven counter-clockwise. The planetary gears rotate counterclockwise. B4 and F3 lock the sun gear so that it cannot rotate in any direction.
The planetary gears rotate counter-clockwise and at the same time move counter-clockwise around the sun gear. The planetary gear carrier and the driving final drive gear rotate counter-clockwise as a unit. The driven final drive gear rotates clockwise at lower speed than the driven intermediate gear.

Position L - 1st gear, engine braking

Secondary shaft (P3):
The driven final drive gear rotates clockwise. The driving final drive gear and the planetary gear carrier rotate counter-clockwise as a unit.
B4 and F3 lock the sun gear so that it cannot rotate in any direction. The planetary gears rotate counter-clockwise and at the same time move counter-clockwise around the sun gear. The ring gear and the driven intermediate gear rotate counter-clockwise.
Primary shaft (P1, P2):
The driving intermediate gear and the planetary gear carrier rotate clockwise as a unit. B3 locks the front planetary train (P2) ring gear so that it cannot rotate in any direction, providing an engine brake. (In D and 3, B3 is not applied, so that no engine braking can be obtained, because of F2.)
The outer planetary gears in P2 rotate counter-clockwise and at the same time move clockwise around the inner planetary gears, which rotate clockwise.
The sun gear shaft rotates counter-clockwise, as B2 and B1 are not applied.
The rear planetary train (P1) ring gear rotates clockwise. C1 connects the rear planetary train ring gear together with the input shaft so that they rotate clockwise as a unit.

Positions D, 3 and L - 2nd gear

Primary shaft (P1, P2):
The input shaft rotates clockwise and C1 connects the input shaft together with the rear planetary train ring gear so that it also rotates clockwise at the input shaft speed.
B2, F1 and B1 prevent the sun gear shaft from rotating in any direction. F2 is in freewheel mode. The inner planetary gears rotate clockwise and at the same time move clockwise around the sun gear shaft. The planetary gear carrier and the driving intermediate gear rotate clockwise as a unit.
Secondary shaft (P3):
The power flow here is the same as in position D for 1st gear. As the driving intermediate gear rotates clockwise, the driven intermediate gear and P3 ring gear will be driven counter-clockwise. The planetary gears rotate counterclockwise.
B4 and F3 lock the sun gear so that it cannot rotate in any direction. The planetary gears rotate counter-clockwise and at the same time move counter-clockwise around the sun gear. The planetary gear carrier and the driving final drive gear rotate counter-clockwise as a unit.
The driven final drive gear rotates clockwise at lower speed than the driven intermediate gear.

Positions D and 3 - 3rd gear

Primary shaft (P1, P2):
The power flow here is the same as in position D for 2nd gear. The input shaft rotates clockwise and C1 connects the input shaft together with the rear planetary train ring gear, so that it also rotates clockwise at the input shaft speed.
B2, F1 and B1 prevent the sun gear shaft from rotating in any direction. (F2 is in freewheel mode.) The inner planetary gears rotate clockwise and at the same time move clockwise around the sun gear shaft. The planetary gear carrier and the driving intermediate gear rotate clockwise as a unit.
Secondary shaft (P3):
Because the driving intermediate gear rotates clockwise, the driven intermediate gear and the ring gear is driven counter-clockwise. C3 connects the sun gear and the planetary gear carrier together.
The planetary train ring gear, the planetary gear carrier, the sun gear and the driving final drive gear rotate counter-clockwise as a unit.
The driven final drive gear rotates clockwise at higher speed than in 2nd gear.

Position D - 4th gear

Primary shaft (P1, P2):
The input shaft rotates clockwise and C1 connects the input shaft together with the rear planetary train ring gear so that it also rotates clockwise at the input shaft speed.
C2 couples the sun gear shaft together with the input shaft so that the sun gear shaft rotates clockwise. The inner planetary gears do not rotate.
B2 and F1 prevent the sun gear shaft from rotating counterclockwise. The entire primary shaft (planetary trains P1 and P2) rotates clockwise as a unit.
The driving intermediate gear rotates clockwise at the input shaft speed.
Secondary shaft (P3):
The power flow is the same as in position D for 3rd gear. The driving intermediate gear rotates clockwise and the driven intermediate gear and the ring gear are driven counter-clockwise.
C3 connects the sun gear and the planetary gear carrier together. (F3 permits freewheel mode.) The planetary train ring gear, the planetary gear carrier, the sun gear and the driving final drive gear rotate counter-clockwise as a unit.
The driven final drive gear rotates clockwise at higher speed than in 2nd gear.

Position R- back-up (reverse) gear

Primary shaft (P1, P2):
The input shaft rotates clockwise and C2 connects the input shaft with the sun gear shaft so that it also rotates clockwise at the input shaft speed. The inner planetary gears rotate counter-clockwise. The outer planetary gears rotate clockwise and at the same time move around the inner planetary gear.
B3 locks the front planetary train ring gear so that it cannot rotate in any direction. The ring gear and the driven intermediate gear rotate counter-clockwise.
Secondary shaft (P3):
Because the driving intermediate gear rotates counter-clockwise, the driven intermediate gear and the ring gear are driven clockwise as a unit. B4 locks the sun gear so that it cannot rotate in any direction.
The planetary gears rotate clockwise and at the same time move clockwise around the sun gear. The planetary gear carrier and the driving final drive gear rotate clockwise. The driven final drive gear rotates counter-clockwise.