General
Combustion engines operate in a limited rpm range. The automatic transmission converts the engine torque into the tractive force required by the wheels to overcome motion resistance.
The automatic transmission is an entirely electronically controlled automatic transmission with nine forward gears and one reverse gear. The gear ratios for the gear ranges are achieved by planetary gear sets. In the automatic transmission, all transmission functions and components are combined in one assembly module.
The fully integrated transmission control controller unit located in the automatic transmission minimizes interfaces to the subharness in the vehicle.
Use of fully integrated transmission control provides the following additional advantages:
High electromagnetic compatibility (prevention of interaction between multiple electronic components)
Fast current control as well as compensation for on-board electrical system fluctuations (increasing shift quality)
Accurate determination of measurements relevant to shift operations and faster evaluation of the measured values
Increased service life, reduced fuel consumption and maximum gearshift comfort can be achieved with the following:
Transmission set-up with nine gears and a steering axis inclination of 9.15
Optimized transmission components
Reduction of working pressure
Software with additional comfort and dynamic functions
Actuation concept with two oil pumps
The transmission can be subdivided into the following assemblies:
Torque converter with torsional damper, centrifugal pendulum and torque converter lockup clutch
Oil pump (primary pump) in off-axis version for generation of required oil pressure and for reliable lubrication of shift elements and bearing points
Electrical transmission oil pump for generating required oil pressure, for guaranteeing lubrication of shift elements and bearing points at engine OFF and for supporting the primary pump
Transmission housing with mechanical transmission components (planetary gear sets, electrohydraulically operated park pawl, multidisk clutches and multidisk brakes)
Fully integrated transmission control controller unit with integrated fully integrated transmission control unit
In terms of design, a distinction is made between four different variants:
P27.10-A054-79
Example illustration of automatic transmission with torque converter and integrated centrifugal pendulum |
1 | Planetary gear set 1 | 11 | Electric transmission oil pump | 21 | Torque converter cover | ||
2 | K38 multiplate clutch | 12 | Piston housing of electrohydraulic parking lock actuator | 22 | Turbine wheel | ||
3 | B05 multidisk brake | 13 | Fully integrated transmission control controller unit | 23 | Stator | ||
4 | Planetary gear system 2 | 14 | Guide tube | 24 | Impeller | ||
5 | Planetary gear set 3 | 15 | Contact carrier of fully integrated transmission control | 25 | Transmission housing breathing | ||
6 | B06 multidisk brake | 16 | Pressure pipe and intake manifold | 26 | Oil pump chain drive | ||
7 | Planetary gear set 4 | 17 | Cover/shift valve body | 27 | Transmission housing | ||
8 | K27 multiplate clutch | 18 | Oil pump | 28 | B08 multidisk brake | ||
9 | Park pawl gear | 19 | Centrifugal pendulum | 29 | Multiplate clutch K81 | ||
10 | Oil pan | 20 | Torque converter lockup clutch |
P27.10-A051-79
Example illustration of automatic transmission with torque converter and engine separator clutch |
30 | Planetary gear set 1 | 40 | Electric auxiliary oil pump | 50 | Engine clutch | ||
31 | K38 multiplate clutch | 41 | Piston housing of electrohydraulic parking lock actuator | 51 | Torque converter cover | ||
32 | B05 multidisk brake | 42 | Fully integrated transmission control control unit | 52 | Electric machine | ||
33 | Planetary gear system 2 | 43 | Supporting body of fully integrated transmission control | 53 | Turbine wheel | ||
34 | Planetary gear set 3 | 44 | Pressure pipe and intake manifold | 54 | Stator | ||
35 | B06 multidisk brake | 45 | Cover/shift valve body | 55 | Impeller | ||
36 | Planetary gear set 4 | 46 | Oil pump | 56 | Oil pump chain drive | ||
37 | K27 multiplate clutch | 47 | Stator | 57 | Transmission housing | ||
38 | Park pawl gear | 48 | Torque converter lockup clutch | 58 | B08 multidisk brake | ||
39 | Oil pan | 49 | Rotor | 59 | Multiplate clutch K81 |
P27.10-A052-79
Example illustration of automatic transmission with torque converter and integrated centrifugal pendulum |
60 | Planetary gear set 1 | 70 | Electric auxiliary oil pump | 80 | Torque converter cover | ||
61 | K38 multiplate clutch | 71 | Piston housing of electrohydraulic parking lock actuator | 81 | Turbine wheel | ||
62 | B05 multidisk brake | 72 | Fully integrated transmission control control unit | 82 | Stator | ||
63 | Planetary gear system 2 | 73 | Guide tube | 83 | Impeller | ||
64 | Planetary gear set 3 | 74 | Supporting body of fully integrated transmission control | 84 | Transmission housing breathing | ||
65 | B06 multidisk brake | 75 | Pressure and oil suction pipes | 85 | Oil pump chain drive | ||
66 | Planetary gear set 4 | 76 | Cover/shift valve body | 86 | Transmission housing | ||
67 | K27 multiplate clutch | 77 | Oil pump | 87 | B08 multidisk brake | ||
68 | Park pawl gear | 78 | Centrifugal pendulum | 88 | Multiplate clutch K81 | ||
69 | Oil pan | 79 | Torque converter lockup clutch |
P27.10-A053-79
Example illustration of automatic transmission with wet clutch |
89 | Planetary gear set 1 | 99 | Electric auxiliary oil pump | 108 | Externally toothed plates | ||
90 | K38 multiplate clutch | 100 | Piston housing of electrohydraulic parking lock actuator | 109 | Internal plates | ||
91 | B05 multidisk brake | 101 | Fully integrated transmission control electric controller unit | 110 | Hub plate | ||
92 | Planetary gear system 2 | 102 | Supporting body of fully integrated transmission control | 111 | Coupling cover | ||
93 | Planetary gear set 3 | 103 | Cover/shift valve body | 112 | Transmission housing breathing | ||
94 | B06 multidisk brake | 104 | Pressure pipe and intake manifold | 113 | Oil pump chain drive | ||
95 | Planetary gear set 4 | 105 | Oil pump | 114 | Transmission housing | ||
96 | K27 multiplate clutch | 106 | Internal plate carrier with torsional damper | 115 | B08 multidisk brake | ||
97 | Park pawl gear | 107 | Wet clutch | 116 | Multiplate clutch K81 | ||
98 | Oil pan |
Additional basic functions | |||
Electric machine, basic function | Model all with transmission 725.0/1 | ||
Park pawl, basic function | Model all with transmission 725.0/1 | ||
Power transmission, basic function | Model all with transmission 725.0/1 | ||
Torque converter lockup clutch control, basic function | Model all with transmission 725.0/1 | ||
Transmission cooling, basic function | Model all with transmission 725.0/1 | ||
Automatic transmission oil supply, basic function | Model all with transmission 725.0/1 | ||
Gearshift system, basic function | Model all with transmission 725.0/1 | ||
Fully integrated transmission control controller unit, basic function | Model all with transmission 725.0/1 |
Referenced documents
- gf0810p2000a Electric machine, basic function
- gf2710p9900a Park pawl, basic function
- gf2710p9901b Power transmission, basic function
- gf2720p1001a Torque converter lockup clutch control, basic function
- gf2755p1000b Transmission cooling, basic function
- gf2757p1003a Automatic transmission oil supply, basic function
- gf2760p1002b Gearshift system, basic function
- gf2760p2003a Fully integrated transmission control controller unit, basic function