A brake assembly is suitable for use with a vehicle wheel that has a rim rotatably mounted to an axle. The brake assembly includes a housing fixedly positioned relative to the axle and a plurality of disks disposed within the housing and fixedly positioned relative to the rim. A fluid is disposed within the housing and has a selectively variable viscosity. The viscosity of the fluid is selectively increased to increase a braking force applied to the wheel.

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.

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 clutch assembly includes a first clutch having a first translator and a friction pack and a second clutch having first and second coupling members, a locking element, and a second translator. The friction pack includes a first plate fixed to the first coupling member and a second plate fixed to the second coupling member. The first translator of the first clutch is movable to an actuated position in which the plates of the friction pack are engaged with one another thereby causing angular velocities of the first and second coupling members to be synchronized. The second translator of the second clutch is movable to an extended position in which the locking element engages the first and second coupling members with one another thereby causing a power flow path through the first and second coupling members.

A clutch assembly includes a first clutch having a first translator and a friction pack and a second clutch having first and second coupling members, a locking element, and a second translator. The friction pack includes a first plate fixed to the first coupling member and a second plate fixed to the second coupling member. The first translator of the first clutch is movable to an actuated position in which the plates of the friction pack are engaged with one another thereby causing angular velocities of the first and second coupling members to be synchronized. The second translator of the second clutch is movable to an extended position in which the locking element engages the first and second coupling members with one another thereby causing a power flow path through the first and second coupling members.

A power transmission device includes a friction clutch, an actuator with an output member, and a controller. The friction clutch is lubricated with a lubricant. The controller is configured to determine a current power state of the friction clutch and determine values for a plurality of thermal coefficients based on the current power state, a set of operation variables, and one or more multi-variable correlation data. The controller is further configured to determine an approximated temperature change of the lubricant based on the values of the plurality of thermal coefficients and a lubricant temperature model. The controller is further configured to determine an approximated lubricant temperature based on the approximated temperature change and a device ambient temperature, and to control operation of the actuator based at least on the approximated lubricant temperature.

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.

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 transfer device of a vehicle is provided, in which an auxiliary-drive-wheel output shaft extending in parallel with a main-drive-wheel output shaft is connected to a propeller shaft having a universal joint. An end part of the auxiliary-drive-wheel output shaft on a propeller shaft side is formed in a hollow shape and includes a fitting part configured to be spline-engaged with a joint part provided to the universal joint. The joint part is provided with a centering part which is inserted into a centering hole formed in a flange part provided to one side of the auxiliary-drive-wheel output shaft so that the joint part is centered on the auxiliary-drive-wheel output shaft. The flange part is sandwiched between a spacer and the joint part, and a bolt member is attached to a bolt hole formed in the centering part so that the propeller shaft is assembled to the auxiliary-drive-wheel output shaft.

A transfer device of a vehicle is provided, in which an auxiliary-drive-wheel output shaft extending in parallel with a main-drive-wheel output shaft is connected to a propeller shaft having a universal joint. An end part of the auxiliary-drive-wheel output shaft on a propeller shaft side is formed in a hollow shape and includes a fitting part configured to be spline-engaged with a joint part provided to the universal joint. The joint part is provided with a centering part which is inserted into a centering hole formed in a flange part provided to one side of the auxiliary-drive-wheel output shaft so that the joint part is centered on the auxiliary-drive-wheel output shaft. The flange part is sandwiched between a spacer and the joint part, and a bolt member is attached to a bolt hole formed in the centering part so that the propeller shaft is assembled to the auxiliary-drive-wheel output shaft.