A vehicle drive train, has a clutch unit actuatable by an actuating unit, and a sensor for determining the coupling status. The actuating unit includes an electromagnetic actuator having a piston movable from a starting to an end position. At least the piston and the clutch are acted on by a transmission fluid. Operating the drive train can include: a) actuating the actuator and moving the piston from the starting position; b) ascertaining a measured sensor value; c) ascertaining a temperature of the transmission fluid by measuring an electrical resistance of the actuator and/or measuring a first time interval between actuation of the actuator according to step a) and the detection by the sensor of an intermediate position that is reached by the piston; d) determining an actual position of the piston based on the measured sensor value and the temperature; and e) moving the piston, starting from the determined actual position, into the end position.

An engagement-type clutch mechanism is provided in which due to the movement of a first power transmission member, which is movably supported on a rotating shaft, toward a second power transmission member, a first and second projecting parts provided on opposing faces of a first and second power transmission members are engaged to each other, and the rotation of the second power transmission member is synchronized with the rotation of the first power transmission member, and due to the movement of a sleeve toward the synchronized second power transmission member, a first spline of the first power transmission member is linked to a second spline of the second power transmission member via a to-be-engaged spline of the sleeve, and the rotation of one of the rotating shaft and the second power transmission member is transmitted to the other of the rotating shaft and the second power transmission member.

A drive switching mechanism of a utility vehicle includes: a two-wheel drive and four-wheel drive switching device that switches between two-wheel drive and four-wheel drive of the utility vehicle; and a control unit that controls the drive switching mechanism. The two-wheel drive and four-wheel drive switching device switches between two-wheel drive and four-wheel drive by using a first clutch. The control unit permits the two-wheel drive and four-wheel drive switching device to switch from two-wheel drive to four-wheel drive when a rotation difference of the first clutch becomes equal to or smaller than a predetermined value.

A system for controlling a clutch is provided with: an action member rotatable about an axis; a motor drivingly connected to the action member to impart a rotational motion about the axis to the action member; a conversion mechanism drivingly connected to the action member to convert the rotational motion about the axis into an axial motion; a clutch member constituting the clutch and drivingly connected to the conversion mechanism so as to be driven by the axial motion, the clutch member being movable axially bidirectionally from a first position where the clutch is disconnected, through a second position, to a third position where the clutch is connected; and a controller configured to measure and compare a rotational angle of the motor with a reference value to determine at which of the first position, the second position, and the third position the clutch member is.

A drive switching mechanism of a utility vehicle includes: a two-wheel drive and four-wheel drive switching device that switches between two-wheel drive and four-wheel drive of the utility vehicle; and a control unit that controls the drive switching mechanism. The two-wheel drive and four-wheel drive switching device switches between two-wheel drive and four-wheel drive by using a first clutch. The control unit permits the two-wheel drive and four-wheel drive switching device to switch from two-wheel drive to four-wheel drive when a rotation difference of the first clutch becomes equal to or smaller than a predetermined value.

A transmission for a vehicle includes a first rotating member for rotation about an axis and a second rotating member for rotation about the axis. The first rotating member and the second rotating member are connectable to each other such that the first rotating member and the second rotating member are rotationally locked relative to each other for transferring torque between the first rotating member and the second rotating member. The transmission comprises a sensor arrangement for measuring a relative angular position of the first rotating member and the second rotating member while at least one of the first rotating member and the second rotating member is rotating.

The invention relates to a coupling arrangement for a gearbox, comprising a coupling sleeve, which is axially displaceable between a first and second position, a first and second rotatable element, which are connectable and disconnectable to each other by means of the coupling sleeve, an electrical machine connected to one of the first and second rotatable element, and a position indicator device for detecting the angular position of a rotor of the electrical machine. The position indicator device also is arranged to detect the axial position of the coupling sleeve.

An engagement-type clutch mechanism is provided in which due to the movement of a first power transmission member, which is movably supported on a rotating shaft, toward a second power transmission member, a first and second projecting parts provided on opposing faces of a first and second power transmission members are engaged to each other, and the rotation of the second power transmission member is synchronized with the rotation of the first power transmission member, and due to the movement of a sleeve toward the synchronized second power transmission member, a first spline of the first power transmission member is linked to a second spline of the second power transmission member via a to-be-engaged spline of the sleeve, and the rotation of one of the rotating shaft and the second power transmission member is transmitted to the other of the rotating shaft and the second power transmission member.

A method for controlling a positive gearshift unit includes, in an engagement procedure, a coupling element, which is connected to a first coupling half and which has a beveled coupling toothing, is brought into engagement with a blocking element, which has a blocking toothing and which is connected to a second coupling half, and is brought into engagement with a catch element, which is connected to the second coupling half, which has a beveled catch toothing, and which is able to move circumferentially with respect to the blocking element. In the engagement procedure, a touch-point is set which comes after a crossing of a synchronous rotational speed in a rotational speed difference profile.

A method of disconnecting a generator from a source of mechanical rotation includes receiving a generator disconnect command and receiving a rotational position of a generator input member. The input member rotational angle is compared to the target disconnect angle range, and a determination made whether to disconnect the input member from a generator drive member based on the comparison.