1997 MERCEDES-BENZ ML320 brake

Fig. 120: Planetary Gear Set, Function (1 Of 5)
Courtesy of MERCEDES-BENZ OF NORTH AMERICA.
Operation
The ring gear (1) and sun gear (3) elements of a planetary gear system are alternately driven and braked by the
actuating elements of the multi-plate clutch and multiple-disc brake. The planet gears (2) can turn on the
internal gearing of the ring gear (1) and on the external gearing of the sun gear (3). This allows for a variety of
gear ratios and the reversal of the rotation direction without the need for moving gear wheels or shift collars.
The torque and speed are converted corresponding to the lever ratios or the ratio of the number of teeth on the
driven to the driving gears and is known as the gear ratio i. The overall ratio of a number of planetary gear sets
connected in series is obtained by multiplying the partial ratios. When two components of the planetary gear set
are locked together, the planetary gear set is locked and turns as a closed unit.
Advantages Of A Planetary Gear Set:
Shifting ability under load.
Several ratios can be produced.
Constant meshing of the gears.
Simple direction reversal.
High efficiency.
Coaxial location of input and output.
Compact design.
The Following Basic Ratio Possibilities Can Be Realized
1.
Sun gear locked.
Ring gear driving.
Planet gears driven.
Relatively low step-down ratio.

2001 Mercedes-Benz ML320
1998-03 AUTOMATIC TRANSMISSIONS Complete Transmissions - ML 320 - 722.662
me
Saturday, October 02, 2010 3:15:28 PMPage 207 © 2006 Mitchell Repair Information Company, LLC.

Fig. 125: Power Flow In 2nd Gear Function
Courtesy of MERCEDES-BENZ OF NORTH AMERICA.
Principals of power transmission in 2nd gear
Torque from the torque converter is increased via the propeller shaft (1) and the center and rear planetary
gearsets and transferred to the output shaft (5). See Fig. 125
.
The following are not engaged:
Front Multi-Disc Brake (B1)
Center Multi-Disc Brake (B3)

2001 Mercedes-Benz ML320
1998-03 AUTOMATIC TRANSMISSIONS Complete Transmissions - ML 320 - 722.662
me
Saturday, October 02, 2010 3:15:28 PMPage 214 © 2006 Mitchell Repair Information Company, LLC.

Freewheel (F1)
Center Multi-Disc Clutch (K2)
Front Planetary Gear Set
The planet carrier (V3) and sun gear (V1) are rigidly connected to each other via the engaged front multi-disc
clutch (K1). The planetary gearset is therefore blocked and turns as a closed unit at the input speed due to the
mechanical connection of the ring gear (V4) and propeller shaft.
Rear Planetary Gear Set
The internal gear (H4) turns at the input speed because of its mechanical connection to the front planet carrier
(V3). The sun gear (H1) is supported via the engaged rear multi-disc brake (B2) and in drive mode via the
locked freewheel (F2), in overrun mode via the engaged rear multi-disc clutch (K3) in the housing. The planet
gears (H2) roll over the fixed sun gear (H1) and provide an increase in torque between the internal gear (H4)
and the planet carrier (H3). The planet carrier (H3) moves at a reduced speed in the direction of engine rotation.
Center Planetary Gear Set
The ring gear (M4) is driven at the same speed as the rear planet carrier (H3) as a result of a mechanical
connection. The sun gear (M1) is supported in the housing via the rear multi-disc brake (B2). The planet gears
(M2) roll over the fixed sun gear (M1) and provide an increase in torque between the internal gear (M4) and the
planet carrier (M3). The output shaft (5) connected to the planet carrier (M3) turns at a reduced speed in the
running direction of the engine.
Torque Converter, Location/Task/Design/Function

See TORQUE CONVERTER, LOCATION/TASK/DESIGN/FUNCTION
.
Planetary Gear Set, Location/Task/Design/Function

See PLANETARY GEAR SET, LOCATION/TASK/DESIGN/FUNCTION
.
Multiple-Disc Brake, Location/Task/Design/Function

See MULTIPLE
-DISC BRAKE, LOCATION/TASK/DESIGN/FUNCTION.
Multi-Plate Clutch, Location/Task/Design/Function

See MULTI
-PLATE CLUTCH, LOCATION/TASK/DESIGN/FUNCTION.
Location/Task/Design/Function Of Freewheel

See LOCATION/TASK/DESIGN/FUNCTION OF FREEWHEEL
.
Power Flow In 3rd Gear Function

2001 Mercedes-Benz ML320
1998-03 AUTOMATIC TRANSMISSIONS Complete Transmissions - ML 320 - 722.662
me
Saturday, October 02, 2010 3:15:28 PMPage 215 © 2006 Mitchell Repair Information Company, LLC.

Fig. 126: Power Flow In 3rd Gear Function
Courtesy of MERCEDES-BENZ OF NORTH AMERICA.
Principal of power transmission in 3rd gear
Torque from the torque converter is increased via the propeller shaft (1) and the center planetary gearset and
transferred to the output shaft (5). See Fig. 126
.
The following are not engaged:
Front multi-disc brake (B1).
Center multi-disc brake (B3).

2001 Mercedes-Benz ML320
1998-03 AUTOMATIC TRANSMISSIONS Complete Transmissions - ML 320 - 722.662
me
Saturday, October 02, 2010 3:15:28 PMPage 216 © 2006 Mitchell Repair Information Company, LLC.

Freewheel F1.
Freewheel F2.
Rear multi-disc clutch (K3).
Front Planetary Gear Set
The planet carrier (V3) and sun gear (V1) are rigidly connected to each other via the engaged front multi-disc
clutch (K1). The planetary gearset is therefore blocked and turns as a closed unit at the input speed due to the
mechanical connection of the ring gear (V4) and propeller shaft.
Rear Planetary Gear Set
The center multi-disc clutch (K2) is engaged and transmits the input speed of the input shaft (1) to the planet
carrier (H3) via the hollow gear (M4). The ring gear (H4) turns in the same way as the planet carrier (H3) due to
the mechanical connection with the locked front planetary gearset. This planetary gearset is therefore locked
and turns as a closed unit.
Center Planetary Gear Set
The hollow gear (M4) rotates at input speed due to the engaged center multi-disc clutch (K2). The sun gear
(M1) is supported in the housing via the multi-disc brake (B2). The planet gears (M2) roll over the fixed sun
gear (M1) and provide an increase in torque between the internal gear (M4) and the planet carrier (M3). The
output shaft (5) connected to the planet carrier (M3) turns at a reduced speed in the running direction of the
engine.
Torque Converter, Location/Task/Design/Function

See TORQUE CONVERTER, LOCATION/TASK/DESIGN/FUNCTION
.
Planetary Gear Set, Location/Task/Design/Function

See PLANETARY GEAR SET, LOCATION/TASK/DESIGN/FUNCTION
.
Multiple-Disc Brake, Location/Task/Design/Function

See MULTIPLE
-DISC BRAKE, LOCATION/TASK/DESIGN/FUNCTION.
Multi-Plate Clutch, Location/Task/Design/Function

See MULTI
-PLATE CLUTCH, LOCATION/TASK/DESIGN/FUNCTION.
Power Flow In 4th Gear Function

2001 Mercedes-Benz ML320
1998-03 AUTOMATIC TRANSMISSIONS Complete Transmissions - ML 320 - 722.662
me
Saturday, October 02, 2010 3:15:28 PMPage 217 © 2006 Mitchell Repair Information Company, LLC.

Fig. 127: Power Flow In 4th Gear Function
Courtesy of MERCEDES-BENZ OF NORTH AMERICA.
Principal of power transmission in 4th gear
The direct drive ratio of 4th gear (i = 1) means that there is no torque and speed conversion. Power is transferred
from the propeller shaft (1) to the input shaft (5) via three locked planetary gearsets (5). See Fig. 127
.
The following are not engaged:
Front Multi-Disc Brake (B1)
Rear Multi-Disc Brake (B2)

2001 Mercedes-Benz ML320
1998-03 AUTOMATIC TRANSMISSIONS Complete Transmissions - ML 320 - 722.662
me
Saturday, October 02, 2010 3:15:28 PMPage 218 © 2006 Mitchell Repair Information Company, LLC.

Center Multi-Disc Brake (B3)
Freewheel F1
Freewheel F2
Front Planetary Gear Set
The planet carrier (V3) and sun gear (V1) are rigidly connected with each other via the engaged front multi-disc
clutch (K1). The planetary gearset is therefore blocked and turns as a closed unit at the input speed due to the
mechanical connection of the ring gear (V4) and propeller shaft.
Rear Planetary Gear Set
The center multi-disc clutch (K2) is engaged and transmits the input speed of the input shaft (1) to the planet
carrier (H3) via the hollow gear (M4). The ring gear (H4) turns in the same way as the planet carrier (H3) due to
the mechanical connection with the locked front planetary gearset. This planetary gearset is therefore locked
and turns as a closed unit.
Center Planetary Gear Set
The hollow gear (M4) rotates at input speed due to the engaged center multi-disc clutch (K2). The rear multi-
disc clutch (K3) connects the sun gears of the center planetary gear set (M1) and the rear planetary gear set
(H1). The planetary gearset is locked by the same speeds of the ring gear (M4) and the sun gear (M1) and it
turns as a closed unit.
Torque Converter, Location/Task/Design/Function

See TORQUE CONVERTER, LOCATION/TASK/DESIGN/FUNCTION
.
Planetary Gear Set, Location/Task/Design/Function

See PLANETARY GEAR SET, LOCATION/TASK/DESIGN/FUNCTION
.
Multi-Plate Clutch, Location/Task/Design/Function

See MULTI
-PLATE CLUTCH, LOCATION/TASK/DESIGN/FUNCTION.
Power Flow In 5th Gear Function

2001 Mercedes-Benz ML320
1998-03 AUTOMATIC TRANSMISSIONS Complete Transmissions - ML 320 - 722.662
me
Saturday, October 02, 2010 3:15:28 PMPage 219 © 2006 Mitchell Repair Information Company, LLC.

Fig. 128: Power Flow In 5th Gear Function
Courtesy of MERCEDES-BENZ OF NORTH AMERICA.
Principles of power transmission in 5th gear
Torque from the torque converter is increased via the propeller shaft (1) and all three planetary gearsets and
transferred to the output shaft (5). See Fig. 128
.
The following are not engaged:
Rear Multi-Disc Brake (B2)

2001 Mercedes-Benz ML320
1998-03 AUTOMATIC TRANSMISSIONS Complete Transmissions - ML 320 - 722.662
me
Saturday, October 02, 2010 3:15:28 PMPage 220 © 2006 Mitchell Repair Information Company, LLC.