Drivetrain for an all-wheel-drive vehicle, and method for controlling the same

摘要

A drivetrain for an all-wheel-drive vehicle which has a first driven axle and a second driven axle. A drive unit is connected to a multi-stage transmission which has a multiplicity of gear stages for generating different transmission ratios. A transmission output shaft of the multi-stage transmission is connected to the first driven axle. The drive unit is also connected to an activating arrangement, the output element of which is connected to the second driven axle. Thus drive power can be supplied to the first axle permanently via the multi-stage transmission and drive power can be supplied to the second axle on demand via the activating arrangement. The activating arrangement has a first activating friction clutch and a second activating friction clutch which are designed to supply drive power to the second axle via a first and a second transmission ratio stage, respectively. The first transmission ratio stage is assigned to at least one lower gear stage of the multi-stage transmission. The second transmission ratio stage is assigned to at least one higher gear stage of the multi-stage transmission.