8.4. Four-wheel drive
| 1 engine 2 – RKPP 3 – drive/differential of a forward axis 4 – driving shaft / forward suspension bracket 5 – driveshaft |
6 – Haldex coupling 7 – conic gear wheels of the drive of a back axis 8 – differential of a back axis 9 – power shafts |
ATTENTION
The all-wheel drive model of the AUDI A3 car is equipped with the constant four-wheel drive. The following elements are in addition necessary for the drive of back wheels:
Knot of selection of power from RKPP of a forward axis to provide transfer of the movement on the driveshaft which connects RKPP to back differential. From differential of a back axis the movement through power shafts is transferred to back wheels.
For a possibility of placement of differential of a back axis the all-wheel drive AUDI A3 model has the double cross lever of a back suspension bracket and the fuel tank, two-piece.
Haldex coupling fixed on differential of a back axis is applied to alignment of various turns of forward and back axes at the four-wheel drive of the car and to distribution of torque depending on traffic conditions, between forward and back axes.
Coupling of Haldex represents disk coupling with electronic control and the hydraulic drive. Depending on the signals arriving from various sensors as, for example, from monitors the engine and the ABS monitor coupling of Haldex regulates process of connection of a back axis. The control system of the four-wheel drive distinguishes the reason of skidding of separate wheels and various speed of wheels and according to it distributes torque between forward and back wheels. The back axis can be disconnected completely from the power drive that lifts limits at towage with the lifted lobbies or back axes. The all-wheel drive model, besides, can be equipped with all electronic and hydraulic systems as, for example, ABS, EDS, ASR, EBV and ESP.
Towage of cars with the four-wheel drive
Cars with the four-wheel drive can be towed on distance no more than 50 km with a speed no more than 50 km/h. Otherwise towage has to be made on the special conveyor by full loading.
ATTENTION