A power transmission device of a four-wheel drive electrically driven vehicle comprises a transverse engine that is supported on one right side surface of two side surfaces of the gear case, and a motor that is supported on the other left side surface of the two side surfaces of the gear case. The power transmission device includes a transfer case that is supported by a gear case and the distributes power from a power source between the left and right front wheels and the left and right rear wheels. The transfer case wraps around from the side surface to a rear surface of the gear case, as seen from above, and outputs power to the left and right rear wheels from the rear surface side of the gear case.

A transfer case includes primary and secondary output shafts, along with a secondary torque transfer mechanism and a locking mechanism, which are configured to selectively couple the primary and secondary output shafts. The secondary torque transfer mechanism comprises a sprocket coupled to the secondary output shaft, and a plate clutch coupled to the sprocket to selectively form a friction coupling with the primary output shaft. The locking mechanism selectively couples the primary output shaft to the sprocket, and includes a locking sleeve and an actuator that moves the locking sleeve between a first position and a second position. In the first position, the locking sleeve forms a first splined connection with the primary output shaft and forms a second splined connection with the sprocket. In the second position, the locking sleeve forms the first splined connection with the primary output shaft and forms a second splined connection with the sprocket.

A transfer case includes an input shaft, a primary output shaft, a secondary output shaft, and an actuator. The primary output shaft is coupled to the input shaft with a gear reduction mechanism. The secondary output shaft is selectively coupleable to the primary output shaft with a secondary torque transfer mechanism. The actuator includes a first actuation mechanism, a second actuation mechanism, and a driver gear assembly. The first actuation mechanism is configured to operate the gear reduction mechanism. The second actuation mechanism is configured to operate the secondary torque transfer mechanism. The drive gear assembly includes a gear plate member, a sense plate member configured to engage the first actuation mechanism, and a hub member configured to engage the second actuation. The sense plate member and the hub member are independently coupled to the gear plate member to rotate in unison with the gear plate member.

A vehicle drive system capable of selectively providing all-wheel drive and single-driven-axle modes includes a front drive unit having a planetary gearset with a grounded ring gear and a sun gear driven by the transaxle's drive spool via an input shaft, and a differential selectively coupled by a dog clutch to one of the sun gear or the planetary carrier, or neither of them, to thereby selectively provide both an available low range and a front axle disconnect. The front drive unit further defines a power take-off unit with a clutch selectively coupling the input shaft to a propshaft. The rear drive unit includes a planetary gearset with a grounded ring gear, a sun gear driven by the propshaft, and a differential selectively coupled by a dog clutch to one of the sun gear or the planetary carrier, or neither of them, to thereby likewise selectively provide both an available low range and a rear axle disconnect.

Methods and systems for a locking mechanism in an inter-axle differential are provided. A vehicle system, in one example, includes an electric motor coupled to a clutch assembly in a locking mechanism of an inter-axle differential coupled to a first axle and a second axle, the clutch assembly is configured to selectively disengage the locking mechanism, and in the disengaged configuration the locking mechanism permits speed differentiation between the first and second axles. The system further includes an electric motor brake coupled to the electric motor and configured to selectively apply a brake torque to the electric motor and the electric motor is configured to actuate the clutch assembly.

Methods and systems for a locking mechanism in an inter-axle differential are provided. A vehicle system, in one example, includes an electric motor coupled to a clutch assembly in a locking mechanism of an inter-axle differential coupled to a first axle and a second axle, the clutch assembly is configured to selectively disengage the locking mechanism, and in the disengaged configuration the locking mechanism permits speed differentiation between the first and second axles. The system further includes an electric motor brake coupled to the electric motor and configured to selectively apply a brake torque to the electric motor and the electric motor is configured to actuate the clutch assembly.

Drive device for a motor vehicle, includes a differential for distributing a torque that can be supplied via a drive shaft to two output shafts and a superimposition gear coupled with the differential one of the output shafts and an additional motor for superimposing torques supplied from the output shaft, from the differential and from the additional motor, wherein the differential is coupled via a torque reducing transmission ratio device with the superimposition gear, wherein the superimposition gear includes a switching device that can be controlled with a control device, wherein the superimposition gear superimposes in a first switching mode torques supplied to the switching device from the output shaft.

Drive device for a motor vehicle, includes a differential for distributing a torque that can be supplied via a drive shaft to two output shafts and a superimposition gear coupled with the differential one of the output shafts and an additional motor for superimposing torques supplied from the output shaft, from the differential and from the additional motor, wherein the differential is coupled via a torque reducing transmission ratio device with the superimposition gear, wherein the superimposition gear includes a switching device that can be controlled with a control device, wherein the superimposition gear superimposes in a first switching mode torques supplied to the switching device from the output shaft.

A vehicle control apparatus includes a planetary gear mechanism, first and second wheels, an engine, a motor generator, a wheel drive clutch, and a control system. The planetary gear mechanism includes first, second, and third rotation elements. The first wheel is coupled to the first rotation element via a first path. The second wheel is coupled to the second rotation element via a second path. The engine is coupled to the third rotation element via a third path. The motor generator is provided on the first path. The wheel drive clutch is provided on the first path and between the motor generator and the first wheel. The control system controls the motor generator and the wheel drive clutch. The control system executes a motor stop mode in which the wheel drive clutch is brought into a released state and the motor generator is brought into a rotation stop state.

A vehicle having a four-wheel-drive system including an auxiliary portion that has an auxiliary driveshaft and drive means between the auxiliary driveshaft arranged to releasably connect a second group of wheels to the driveline via a releasable torque transmitting device. The releasable torque transmitting device is operable to allow slippage of the input portion with respect to the output portions, thereby to vary an amount of torque that is transmitted to the second group of wheels.