In an engagement device provided with a hydraulic actuator having an oil bag expanding and contracting in an engaging direction and a releasing direction, an annular engagement plate moved by the oil bag in the engaging direction and the releasing direction, and a return mechanism that urges the engagement plate in the releasing direction, the engagement plate is an engagement element whose surface on the releasing direction side is in contact with the oil bag, and the return mechanism moves the engagement plate in the releasing direction and presses the oil bag through the engagement plate.

Power transmission systems including clutch arrangements and systems are adapted to be used in marine and other environments. Such power transmission systems may include clutch arrangements that provide more effective power transmission capabilities as well as greater durability and longer life. Slipping clutch arrangements may effectively vary the output speed of a clutch arrangement from the speed of the engine or other driver as desired for the particular application. Various clutch arrangements also provide for greater flexibility and drive options, lighter weight, and diverse types of capabilities.

A coupling arrangement for the powertrain of a vehicle with a clutch housing with a feed arrangement for feed medium contained in the clutch housing and with a clutch mechanism, wherein the clutch mechanism has input-side clutch units communicating with an input-side clutch unit carrier, output-side clutch units communicating with an output-side clutch unit carrier, and a pressing device through which an operative connection between the input-side clutch units and the output-side clutch units can be produced or cancelled, and wherein the input-side clutch unit carrier is part of the feed arrangement. The feed arrangement further has a feed device which is associated with the input-side clutch unit carrier and which is connected to the input-side clutch unit carrier and/or to the pressing device so as to be fixed with respect to relative rotation.

A multiple disc clutch includes an axially displaceable outer disc hooked into an outer disc carrier to provide a first friction surface, and an axially displaceable inner disc hooked into an inner disc carrier to provide a second friction surface for a friction pairing with the first friction surface. The outer disc has an outer coupling element for coupling to the outer disc carrier and the inner disc has an inner coupling element for coupling to the inner disc carrier. The outer disc has an outer ring, the outer coupling element extends radially from the outer ring, and the first friction surface is connected to the outer ring by an outer leaf spring element; or the inner disc has an inner ring, the inner coupling element extends radially from the inner ring, and the second friction surface is connected to the inner ring by an inner leaf spring element.

A multiple disc clutch includes an axially displaceable outer disc hooked into an outer disc carrier to provide a first friction surface, and an axially displaceable inner disc hooked into an inner disc carrier to provide a second friction surface for a friction pairing with the first friction surface. The outer disc has an outer coupling element for coupling to the outer disc carrier and the inner disc has an inner coupling element for coupling to the inner disc carrier. The outer disc has an outer ring, the outer coupling element extends radially from the outer ring, and the first friction surface is connected to the outer ring by an outer leaf spring element; or the inner disc has an inner ring, the inner coupling element extends radially from the inner ring, and the second friction surface is connected to the inner ring by an inner leaf spring element.

A multi-plate clutch includes an outer plate suspended on a radial outside and axially displaceable, an inner plate suspended on a radial inside and axially displaceable, and a plurality of leaf springs. The plurality of leaf springs is distributed around an outer circumference of the outer plate to suspend the outer plate in a torque-transmitting manner on a rotor pot, or the plurality of leaf springs is distributed in an inner circumference of the inner plate to suspend the inner plate in a torque-transmitting manner on a driving ring. In an example embodiment, the multi-plate clutch is a dry multi-plate clutch for a hybrid drivetrain. In an example embodiment, the multi-plate clutch includes a plurality of outer plates and a plurality of inner plates.

A secondary drive unit (SDU) for the secondary axis of an all wheel drive vehicle consists of an SDU housing defining a first section for receiving a main shaft which is connected to a drive source and a second section for enclosing a twin clutch assembly. The twin clutch assembly has a common clutch housing connected to the main shaft, a left clutch for selectively connecting a left output shaft and the clutch housing, a right clutch for selectively connecting a right output shaft and the clutch housing, and a rigid center plate separating the left and right clutches. The twin clutch assembly may be activated by a dual action piston assembly to decrease all wheel drive synchronization and connection response times.

A secondary drive unit (SDU) for the secondary axis of an all wheel drive vehicle consists of an SDU housing defining a first section for receiving a main shaft which is connected to a drive source and a second section for enclosing a twin clutch assembly. The twin clutch assembly has a common clutch housing connected to the main shaft, a left clutch for selectively connecting a left output shaft and the clutch housing, a right clutch for selectively connecting a right output shaft and the clutch housing, and a rigid center plate separating the left and right clutches. The twin clutch assembly may be activated by a dual action piston assembly to decrease all wheel drive synchronization and connection response times.

The present disclosure provides a wet friction engaging device. The device includes a plate group engaged with two connecting members and including two groups of friction plates housed in a plate housing chamber and alternately arranged in an axial direction with surfaces facing each other. The plate group is switched between an engaged state in which the friction plates are in close contact with each other, and a disengaged state in which the friction plates are separable from each other. End plates at respective ends of the plate group are kept at a larger distance in the axial direction after a switch to the disengaged state than in the engaged state.

The present disclosure provides a wet friction engaging device. The device includes a plate group engaged with two connecting members and including two groups of friction plates housed in a plate housing chamber and alternately arranged in an axial direction with surfaces facing each other. The plate group is switched between an engaged state in which the friction plates are in close contact with each other, and a disengaged state in which the friction plates are separable from each other. End plates at respective ends of the plate group are kept at a larger distance in the axial direction after a switch to the disengaged state than in the engaged state.