A dog clutch of a vehicle power transmission device includes a sleeve, the dog clutch connecting/disconnecting a first rotating shaft to/from a first gear by moving the sleeve between a neutral position at which inner circumferential teeth formed on an inner circumferential side of the sleeve are not meshed with outer circumferential teeth on a side surface side of the first gear and an engagement position at which the inner circumferential teeth are meshed with the outer circumferential teeth, the inner circumferential teeth and the outer circumferential teeth having inclined surfaces tooth thicknesses of which become larger as the inner circumferential teeth and the outer circumferential teeth approach each other, and when the sleeve is moved to an engagement position by a shift fork, the sleeve being held in contact with a side surface of the first gear.

A four-wheel drive vehicle comprises: main drive wheels; sub-drive wheels; a power transmission path; a first connecting/disconnecting device; and a second connecting/disconnecting device, at least one connecting/disconnecting device of the first and second connecting/disconnecting devices including: a dog clutch; a synchronization mechanism; and an electromagnetic actuator. The four-wheel drive vehicle includes a control device providing the energization control of the electromagnetic coil based on a preliminarily stored current command value to engage the dog clutch of the one connecting/disconnecting device, and the control device learns a characteristic value indicative of an increasing characteristic of the rotation speed of the first rotating member with respect to the current command value and updates the current command value such that an increase rate of the rotation speed of the first rotating member becomes equal to a predetermined rate based on the learned characteristic value.

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 shifting system includes an input member, a disconnect, an output member, and a shifting assembly to selectively rotationally couple the input member and the output member. The shifting assembly includes an input hub having a disconnectable component engageable with the disconnect and a clutch engagement component extending radially away from an axis. A plurality of clutch plates is coupled to the clutch engagement component and is moveable between engaged and disengaged positions. A biasing member is coupled to the clutch plates to bias the clutch plates toward the engaged position, and an apply plate is coupled to the biasing member. The apply plate is moveable between a first plate position where the clutch plates are in the engaged position, and a second plate position where the clutch plates are in the disengaged position. A clutch plate carrier is coupled to the clutch plates and to the output member.

A clutch system configured to transmit torque between an input shaft and an output shaft. The clutch system may include a clutch and a lubrication supply system. The clutch may include: an input portion disposed at an end of the input shaft; an output portion disposed at an end of the output shaft; and a sliding component that slides axially between the input and output portions to engage the clutch. The lubrication supply system may include: one or more lubricant feeds for delivering a lubricant to the clutch; and one or more lubricant drains for draining the lubricant from the clutch. The one or more lubricant feeds may include one or more respective valves. The one or more valves each may be configurable between settings that vary an amount of the lubricant delivered to the clutch via the respective one of the one or more lubricant feeds.

A clutch arrangement (3) with a friction clutch (8) and a dog clutch (9), wherein the output side of the friction clutch (8) and the output side of the dog clutch (9) are connectible to a flywheel mass device (4). A powertrain unit having such clutch arrangement is also described.

A coupling device for transmitting a torque from a flywheel mass to a drive device. A ratchet wheel and a transmission element of the flywheel mass ‘SUE’, which is identical to the flywheel mass (or is connected to the flywheel mass, are axially displaceable relative to one another, and pawls of the ratchet wheel can be moved into cutouts of the SUE, and a friction device, particularly in the form of a friction cone, is connectable to the SUE at least partially in a frictionally engaging manner and is connected to the ratchet wheel in a positively engaging manner.

A clutch that has a synchronizer for matching a rotational velocity of a drive input with a rotational velocity of a driven output prior to engagement of a locking mechanism.

A clutch that has a synchronizer for matching a rotational velocity of a drive input with a rotational velocity of a driven output prior to engagement of a locking mechanism.

A four-wheel drive vehicle comprises: main drive wheels and sub-drive wheels; a first input rotating member; a first output rotating member; a second input rotating member; a second output rotating member; a first dog clutch; a second dog clutch; a synchromesh mechanism. In the case of canceling a disconnect state in which the power transmitting member interrupts power transmission from the drive power source and the sub-drive wheels, the control device controls an engagement torque of the coupling to a preset first torque and operates the synchromesh mechanism to engage the first dog clutch when it is determined that the rotation speeds are synchronized between the second input rotating member and the second output rotating member, and controls the engagement torque of the coupling to a second torque smaller than the first torque to engage the second dog clutch when it is determined that the first dog clutch is engaged.