A clutch control device is provided for a four-wheel drive vehicle for transmitting drive force to the rear wheels. The clutch control device includes a dog clutch and a friction clutch, and a 4WD control unit that controls the engagement and disengagement of the dog clutch and the friction clutch. The 4WD control unit has as two-wheel drive modes, a disconnected two-wheel drive mode in which the dog clutch and the friction clutch are released, and a standby two-wheel drive mode in which the dog clutch is engaged and the friction clutch is released. The 4WD control unit is programmed to switch to the standby two-wheel drive mode when uphill movement is detected during the disconnected two-wheel drive mode.

A clutch control device is provided for a 4-wheel drive vehicle. The clutch control device includes a 4WD control unit that controls the engagement and release of a friction clutch and a dog clutch which are arranged separately in the two paths. The 4WD control unit has a synchronization speed control unit, and at a time of transition from a disconnected, two-wheel drive mode, in which the friction clutch and the dog clutch are released, to a connected, four-wheel drive mode, in which the friction clutch and the dog clutch are engaged, the synchronization speed control unit reduces a synchronization speed of the dog clutch more during vehicle deceleration than when the vehicle is not decelerating.

A clutch control device is provided for a four-wheel drive vehicle. The clutch control device is able to suppress the elevation of the temperature of the oil supplied to a friction clutch during two-wheel drive travel when the friction clutch is released. The clutch control device includes a dog clutch and an electronic control coupling. The friction clutch is housed in a coupling case. When the dog clutch and the friction clutch are released, a two-wheel drive mode is selected. The coupling case has a passage opening that is closed to retain lubrication oil in an oil chamber with respect to a clutch chamber that houses the friction clutch. When oil stirring conditions are met thereafter, the passage opening is opened and the lubrication oil is allowed to flow into the clutch chamber from the oil chamber.

A clutch control device is provided for a 4-wheel drive vehicle. The clutch control device includes a 4WD control unit that controls the engagement and release of a friction clutch and a dog clutch which are arranged separately in the two paths. The 4WD control unit has a synchronization speed control unit, and at a time of transition from a disconnected, two-wheel drive mode, in which the friction clutch and the dog clutch are released, to a connected, four-wheel drive mode, in which the friction clutch and the dog clutch are engaged, the synchronization speed control unit reduces a synchronization speed of the dog clutch more during vehicle deceleration than when the vehicle is not decelerating.

A clutch control device is provided for a four-wheel drive vehicle for transmitting drive force to the rear wheels. The clutch control device includes a dog clutch and a friction clutch, and a 4WD control unit that controls the engagement and disengagement of the dog clutch and the friction clutch. The 4WD control unit has as two-wheel drive modes, a disconnected two-wheel drive mode in which the dog clutch and the friction clutch are released, and a standby two-wheel drive mode in which the dog clutch is engaged and the friction clutch is released. The 4WD control unit is programmed to switch to the standby two-wheel drive mode when uphill movement is detected during the disconnected two-wheel drive mode.

A vehicle driveline system (100) is provided comprising a differential (120) having an input (102), a front output (106) connecting to a front axle (12) and a rear output (104) connecting to a rear axle (14). The vehicle driveline system (100) further comprises an actuator (130) which is configured to control the operation of the differential (120) between a first mode, in which the front output (106) is disconnected from the input (102), and a second mode, in which the front output (106) is connected to the input (102).

An axle drive mechanism includes a driving toothed wheel, a drive mechanism housing, a differential cage, a differential gear, a first and a second output shaft, and at least one shiftable torque transmission device. The at least one shiftable torque transmission is disposed between the driving toothed wheel and the first output shaft and includes a torque transmission region. The torque transmission region is at least partially disposed between said differential cage bearings in the axial direction.

In a motor vehicle drive train arrangement with at least one main drive train for driving a main drive axle, and at least one auxiliary drive train which is driven via the main drive train and connected to a secondary drive axle which can be driven via the auxiliary drive train, the secondary drive axle is linked to the auxiliary drive train without an axle differential and the secondary drive axle includes controllable couplers for selectively coupling the secondary drive axle wheels to the auxiliary drive train.

A clutched device can include a differential and first and second conduits. The differential can transmit differential power to first and second outputs. Clutch plates can rotate through a clutch cavity and transmit power between the second output and a third output. An outer carrier and an inner carrier can be coupled for rotation with the second and third outputs, respectively. The first conduit can be open to a first peripheral region of the clutch cavity and fluidly couples the first region to a cavity separate from the clutch cavity. The second conduit can be open to a second peripheral region that is circumferentially spaced apart from the first region. The second conduit can fluidly couple the second region to a central region of the clutch cavity. Rotation of the outer carrier in opposite rotational directions slings lubricant to the first and second conduits, respectively.

A control device for a four wheel drive vehicle. Differential limitation is applied to both of right and left rear wheels, with 2WD_d state being maintained, by executing two wheel control for engaging or half-engaging a first clutch and a second clutch. As the two wheel drive control is executed, a moment that suppresses the rotation speed difference between the right and left rear wheels acts on the right and left rear wheels even in the 2WD_d state. When the rotation speed difference occurs between the right and left rear wheels, a braking force is allowed to act on the vehicle wheel on the high rotation side and a driving force is allowed to act on the vehicle wheel on the low rotation side through the execution of the two wheel drive control so that a stable moment acts on the vehicle without a transition to a 4WD state.