A first engagement member rotates integrally with a first shaft. A second engagement member rotates integrally with a second shaft. An electric clutch device drives the first engagement member with a pressing member that extends and contracts in response to drive of the clutch actuator. The drive control unit performs a position control to control the clutch actuator, such that a drive amount of the first engagement member becomes a target stroke amount, when the first engagement member and the second engagement member are separated from each other and performs a pressing force control to control the clutch actuator, such that the pressing force between the first engagement member and the second engagement member becomes a target pressing force, when the first engagement member and the second engagement member are engaged with each other.

An electromagnetic clutch assembly may include a first clutch plate, a second clutch plate, and a synchronizer. The second clutch plate may define an aperture. A portion of the synchronizer may be configured to extend through the aperture. In the absence of a magnetic field, the first clutch plate and the first surface of the second clutch plate may define an air gap and the portion of the synchronizer may extend into the air gap. In response to a first magnetic field, the portion of the synchronizer may contact the first clutch plate. In response to a second magnetic field, the portion of the synchronizer may translate in the aperture toward the second clutch plate and the first clutch plate and the second clutch plate may close the air gap.

A motor assembly, control system and associated method monitor the rotational engagement of an input shaft associated with a motor with an output shaft configured to controllably position a control surface. In this regard, a control system includes a motor assembly and an associated controller. The motor assembly includes a motor configured to rotate an input shaft and a first encoder configured to determine a rotational position of the input shaft. The motor assembly also includes an output shaft, such as a capstan, and a second encoder configured to determine a rotational position of the output shaft. The output shaft is rotatably coupled to the input shaft associated with the motor via a clutch. The controller is configured to identify slippage of the clutch based upon information provided by the first and second encoders regarding the rotational positions of the input shaft and the output shaft, respectively.

A transmission includes an input shaft coupled to a prime mover, a countershaft, main shaft, and an output shaft, with gears between the countershaft and the main shaft. A shift actuator selectively couples the input shaft to the main shaft by rotatably coupling gears between the countershaft and the main shaft. The shift actuator is mounted on an exterior wall of a housing including the countershaft and the main shaft. An integrated actuator housing includes a single external power access for the shift actuator. A controller interprets a shaft displacement angle, determines if the transmission is in an imminent zero or zero torque region, and performs a transmission operation in response to the transmission in the imminent zero or zero torque region.

A method ascertains a characteristic variable of a clutch installed into the powertrain of a vehicle for transmitting torque between a clutch input and a clutch output. A first electric motor is connected to the clutch input to introduce a first drive torque into the clutch. The torque is ascertained when the vehicle is at a standstill in that the clutch is first opened; the first electric motor is regulated at a first rotational speed; the clutch output is regulated at a second rotational speed; a counter torque which counteracts the transmission torque is applied to the clutch output; the clutch is then closed in order to assume a slipping state in which a specific differential rotational speed between the clutch input and the clutch output is present; the first drive torque is then ascertained; and the transmission torque is determined on the basis of the first drive torque.

A method of operating a vehicle drivetrain for rocking the vehicle free. The drivetrain has a transmission with an input and an output that can be coupled by a clutch. The input and output are connected to a drive aggregate and a drive output, respectively. The clutch is actuated based on driver actuation of an accelerator and a rotational speed of the drive output such that following accelerator actuation, when its actuation decreases, the clutch disengages with a first opening gradient. Then, based on a calculated point in time at which drive aggregate torque upon the clutch corresponds to torque on the clutch from the drive output, the clutch disengages with a second, smaller opening gradient. And depending on a rotational speed of the drive output relative to a limit value, the clutch either initiates or terminates engagement with a first closing gradient.

A vehicle includes: a transmission including an input shaft that receives power inputted from a power source for travel of the vehicle and an output shaft that outputs power to a drive wheel; a manual gear shifting power transmission mechanism that delivers an operation force of a driver as gear shifting power to the transmission; a clutch disposed between the power source for travel of the vehicle and the input shaft; and a controlled clutch actuation power transmission mechanism that delivers power of a clutch actuator as clutch actuation power to the clutch.

A coupling assembly has a second coupling member mounted for rotation and a first coupling member having a speed sensor to sense a speed of rotation of the second coupling member. The coupling assembly further has a forward and a reverse locking element movable between (i) a coupling position in which the locking elements engage the second coupling member to thereby prevent rotation of the second coupling member in opposite first and second directions and (ii) a non-coupling position. Upon the speed of rotation of the second coupling member decreasing to be lower than a hill-hold speed threshold, the reverse locking element is moved to the coupling position while the forward locking element is maintained in the non-coupling position. Irrespective of a Park command, the locking elements are maintained in the non-coupling position while the speed of rotation of the second coupling member is greater than a park speed threshold.

A transmission is subject to gear shift management that provides for shifting gears in a controlled manner in order to provide for a simplification of part and reduction in system complexity. In particular, a range synchronizer component can be replaced with a simplified range jaw clutch, without incurring a requirement for an installation of other components such as a motor generator or starter-generator.

A method for controlling a clutch unit for a drive train of a motor vehicle, wherein the clutch unit comprises a wet-running friction clutch for controllably transmitting torque from an input element to an output element of the clutch unit, wherein the clutch unit comprises oil for cooling the friction clutch, wherein heat inputs which contribute to heating the oil of the clutch unit are calculated, heat outflows which contribute to cooling the oil of the clutch unit are calculated and, as a function of the heat inputs and heat outflows, a maximum admissible clutch torque is calculated, and wherein the current clutch torque of the friction clutch is limited to the maximum admissible clutch torque.