Methods and system are described for changing a driveline gear range from a lower gear range to a higher gear range. The driveline may include two electric machines and four clutches in a four wheel drive configuration. The methods and systems permit a driveline to change from a lower gear range to a higher gear range in a way that may reduce torque disturbances that may result from gear lash.

The present invention provides a powertrain comprising a transmission (2), a first electric motor (4a) and a second electric motor (4b), wherein the transmission comprises an input shaft (1) to which a source of mechanical power may be connected, an output shaft (6) and a gear assembly providing at least two different gear ratios that may be selected for transfer of mechanical power from the input shaft (1) to the output shaft (6), the first electric motor (4a) is connected to the input shaft (1), such that torque and rotation may be transferred between the first electric motor and the input shaft, and the second electric motor (4b) is connected to the input shaft (1) via a first clutch (5a), such that torque and rotation may be transferred between the second electric motor (4b) and the input shaft (1), and connected to the output shaft (6) via a second clutch (5b), such that torque and rotation may be transferred between the second electric motor (4b) and the output shaft (6), wherein the first electric motor (4a) is connected to the second electric motor (4b) via the first clutch (5a).

Methods and systems are provided for operating a driveline of a four wheel drive vehicle that includes a high gear ratio and a low gear ratio. The driveline may be operated to shift between the high gear ratio and the low gear ratio while the four wheel drive vehicle is moving. In one example, a clutch is opened during shifting from the high gear ratio to the low gear ratio, which allows the vehicle to continue traveling during the gear ratio change.

Provided is a vehicle drive system capable of suppressing a feeling of acceleration drop and free running, thereby improving vehicle riding comfort. The vehicle drive system includes: an internal combustion engine for driving a primary drive wheel; a stepped variable transmission; an assist motor for driving a secondary drive wheel; and a motor control device for controlling the assist motor, wherein the stepped variable transmission is a seamless-shift transmission configured such that a drive force to be transmitted therethrough is interrupted during shifting down, but not substantially interrupted during shifting up, and the motor control device is operable, during the shifting down by the stepped variable transmission, to cause the assist motor to generate a drive force to compensate for the interruption of the drive force.

A hybrid powertrain may include an engine input shaft connected to an engine by a main clutch, a motor input shaft connected to a motor, first and second output shafts mounted in parallel to the engine input shaft, a variable driving gear provided on the motor input shaft to maintain or increase a rotation speed of the motor input shaft and then to transmit the maintained or increased rotation speed to the first output shaft, a composite synchronizer mounted to independently implement interruption of connection between the engine input shaft and the motor input shaft and interruption of connection between the variable driving gear and the motor input shaft, and plural gear pairs mounted to form different transmission gear ratios between the engine input shaft and the first output shaft and between the engine input shaft and the second output shaft.

The invention relates to a vehicle axle, comprising: a differential; a powertrain, comprising a first electric motor (EM1) and a second electric motor (EM2); a first transmission element between the first electric motor and said differential, this first transmission element comprising a variable transmission ratio; a second transmission element between the second electric motor and said differential; wherein the second electric motor is controlled so as to provide its maximum power during gear changes of the first transmission element, so as to compensate at least partially for the power loss inherent in the gear change.

Methods and systems are provided for operating a driveline of a four wheel drive vehicle that includes a high gear ratio and a low gear ratio. The driveline may be operated to shift between the high gear ratio and the low gear ratio while the four wheel drive vehicle is moving. In one example, a clutch is opened during shifting from the high gear ratio to the low gear ratio, which allows the vehicle to continue traveling during the gear ratio change.

One general aspect of the present disclosure includes a hybrid drive for a motor vehicle. The hybrid drive may have a first transmission input shaft configured to connect to an internal combustion engine, a second transmission input shaft being coaxial to the first transmission input shaft and configured to connect to an electric motor, a first gear set plane, a second gear set plane, and a third gear set plane for a first forward gear, a second forward gear, and a third forward gear, respectively, a layshaft, a first gear shifting device connecting the first transmission input shaft and the second transmission input shaft in a first shifting setting and engaging a gear in a second shifting setting, and a transmission output shaft.

A drive device and methods for operating a drive device of a motor vehicle, having an internal combustion engine, an electric machine, and a dual-clutch transmission. The dual-clutch transmission has two clutches, by means of which the transmission can be connected to the internal combustion engine. At least the internal combustion engine is actuated in a driving operation in order to generate a target drive torque, and the clutches are actuated in opposite directions for a gear shift. During a gear shift, the electric machine, which is connected to the dual-clutch transmission without a clutch, is actuated such that the electric machine completely or partly generates the target torque at least temporarily.

A driveline for a tractor including a transmission; a differential; a driveshaft configured to transfer torque from the transmission to the differential; and an auxiliary drive system. The auxiliary drive system includes a motor and an electrical energy storage device. The motor is powered by the electrical energy storage device and configured to apply torque to the driveshaft.