Torque of a prime mover is input into a sun gear. A planetary gear revolves in a circumferential direction of the sun gear while rotating and meshing with the sun gear. A carrier has an annular shape, rotatably supports the planetary gear, and is rotatable relative to the sun gear. A first ring gear is fixed to a housing, and meshes with the planetary gear. A second ring gear meshes with the planetary gear, is different from the first ring gear in number of teeth of a tooth portion, and outputs torque to a rotation portion. At least a part of the sun gear in an axial direction is located radially inward of the carrier. At least a part of the first ring gear and at least a part of the second ring gear in the axial direction are located radially outward of the carrier.

A sun gear of a speed reducer is provided coaxially with and integrally rotatably with a rotor of a prime mover. Multiple planetary gears are disposed in a circumferential direction of the sun gear, and are capable of revolving in the circumferential direction of the sun gear while rotating in a state of meshing with the sun gear. A carrier rotatably supports the planetary gears, and is rotatable relative to the sun gear. A first ring gear is fixed to a housing, and has a first ring gear tooth portion capable of meshing with the planetary gears. A second ring gear is rotatable integrally with a rotation portion, and has a second ring gear tooth portion capable of meshing with the planetary gears. The second ring gear tooth portion is different in number of teeth from the first ring gear tooth portion.

A rotational translation unit includes a rotation portion that rotates relative to a housing upon receiving an input of torque output from a speed reducer, and a translation portion that moves relative to the housing in an axial direction according to rotation of the rotation portion relative to the housing. A clutch is provided between a first transmission portion and a second transmission portion that are rotatable relative to the housing, and the clutch allows transmission of the torque between the first transmission portion and the second transmission portion in an engaged state of the clutch, and interrupts the transmission of the torque between the first transmission portion and the second transmission portion in a disengaged state of the clutch. A return spring is capable of urging the rotational translation unit in a direction away from the clutch relative to the housing.

A state changing unit is capable of contacting a clutch, and being configured to receive a force along the axial direction from a translation portion and change a state of the clutch to an engaged state or a disengaged state according to a position of the translation portion in an axial direction relative to a housing. A fixed end is non-rotatable relative to the housing. A return spring is disposed on a side of the fixed end opposite to the clutch, and capable of urging the translation portion in a direction away from the clutch with respect to the fixed end.

A state changing unit is capable of contacting a clutch, and being configured to receive a force along the axial direction from a translation portion and change a state of the clutch to an engaged state or a disengaged state according to a position of the translation portion in an axial direction relative to a housing. A fixed end is non-rotatable relative to the housing. A return spring is disposed on a side of the fixed end opposite to the clutch, and capable of urging the translation portion in a direction away from the clutch with respect to the fixed end.

A rear drive module for an all-wheel drive motor vehicle includes a differential assembly having an outer differential housing and an inner differential housing, the inner differential housing being fixed for rotation with an output shaft of the differential assembly; a ring gear assembly having a ring gear mounted to and fixed for rotation with the outer differential housing; and a disconnect and synch-lock mechanism: operable to synchronize and lock the inner differential housing and the outer differential housing, and to disconnect the inner differential housing and the outer differential housing to prevent rotation of the outer differential housing and the ring gear. The disconnect and synch-lock mechanism may include a synchronizer clutch and a clutch actuator. The clutch actuator may be a ball-ramp or face cam mechanism which is configured to control the operation of the synchronizer clutch and locking between the inner and outer differential housings.

A rear drive module for an all-wheel drive motor vehicle includes a differential assembly having an outer differential housing and an inner differential housing, the inner differential housing being fixed for rotation with an output shaft of the differential assembly; a ring gear assembly having a ring gear mounted to and fixed for rotation with the outer differential housing; and a disconnect and synch-lock mechanism: operable to synchronize and lock the inner differential housing and the outer differential housing, and to disconnect the inner differential housing and the outer differential housing to prevent rotation of the outer differential housing and the ring gear. The disconnect and synch-lock mechanism may include a synchronizer clutch and a clutch actuator. The clutch actuator may be a ball-ramp or face cam mechanism which is configured to control the operation of the synchronizer clutch and locking between the inner and outer differential housings.

Pump assembly for recirculating a cooling fluid of a heat engine, comprising: a pump body, an impeller driven by a driven shaft and inserted in a chamber of the circuit for recirculating the cooling fluid of the heat engine; at least a reversible friction clutch, adapted to transmit the motion from motion generating means, coupled to the motor shaft of the vehicle, to the driven shaft, an electric motor to drive said driven shaft independently of the heat engine; wherein said electric motor and said friction clutch are arranged in an axially external position with respect to the motion generating means of the clutch. Preferably, said electric motor is axially opposed to the friction clutch with respect to the motion generating means, and is axially adjacent to the chamber of the impeller in the axial direction.

Pump assembly for recirculating a cooling fluid of a heat engine, comprising: a pump body, an impeller driven by a driven shaft and inserted in a chamber of the circuit for recirculating the cooling fluid of the heat engine; at least a reversible friction clutch, adapted to transmit the motion from motion generating means, coupled to the motor shaft of the vehicle, to the driven shaft, an electric motor to drive said driven shaft independently of the heat engine; wherein said electric motor and said friction clutch are arranged in an axially external position with respect to the motion generating means of the clutch. Preferably, said electric motor is axially opposed to the friction clutch with respect to the motion generating means, and is axially adjacent to the chamber of the impeller in the axial direction.

A disconnect clutch comprises a passive centrifugal valve that is utilized to disconnect parasitic loads from an engine during the initial start-up and to automatically connect the parasitic loads once the engine speed is sufficient. The passive centrifugal valve operates dependent on a rotational speed of a flywheel assembly of the clutch and is configured to switch at a threshold rotational speed of the flywheel assembly.