A drive train system includes a source of rotational energy, a viscous coupling and power take off assembly that is rotatably driven by the source of rotational energy, and a rotatably driven device that is rotatably driven by the viscous coupling and power take off assembly. The viscous coupling and power take off assembly may include a power take off that is rotatably driven by the source of rotational energy and a viscous coupling that is rotatably driven by the power take off. Alternatively, the viscous coupling and power take off assembly may include a viscous coupling that is rotatably driven by the source of rotational energy and a power take off that is rotatably driven by the viscous coupling. Lastly, the viscous coupling and power take off assembly may include a combined viscous coupling and power take off assembly that is integrated into a single housing.

A drive train system includes a source of rotational energy, a viscous coupling and power take off assembly that is rotatably driven by the source of rotational energy, and a rotatably driven device that is rotatably driven by the viscous coupling and power take off assembly. The viscous coupling and power take off assembly may include a power take off that is rotatably driven by the source of rotational energy and a viscous coupling that is rotatably driven by the power take off. Alternatively, the viscous coupling and power take off assembly may include a viscous coupling that is rotatably driven by the source of rotational energy and a power take off that is rotatably driven by the viscous coupling. Lastly, the viscous coupling and power take off assembly may include a combined viscous coupling and power take off assembly that is integrated into a single housing.

An active differential for the controlled distribution of a drive torque generated by a drive motor to two drive shafts includes a planetary gear train configured to couple the two drive shafts to a drive shaft of the drive motor, and a distributor motor including a distributor shaft. The distributor motor produces a torque, with a distribution of a drive torque to the two drive shafts being dependant on the torque produced by the distributor motor. The distributor shaft and the planetary gear train are coupled by a coupling device which only transmits a torque from the planetary gear train to the distributor shaft when a rotational speed difference between rotational speeds of the two output shafts exceeds a predetermined limit value and when a connection condition depending on an operating condition of the distributor motor is satisfied.

An active differential for the controlled distribution of a drive torque generated by a drive motor to two drive shafts includes a planetary gear train configured to couple the two drive shafts to a drive shaft of the drive motor, and a distributor motor including a distributor shaft. The distributor motor produces a torque, with a distribution of a drive torque to the two drive shafts being dependant on the torque produced by the distributor motor. The distributor shaft and the planetary gear train are coupled by a coupling device which only transmits a torque from the planetary gear train to the distributor shaft when a rotational speed difference between rotational speeds of the two output shafts exceeds a predetermined limit value and when a connection condition depending on an operating condition of the distributor motor is satisfied.