An all-wheel-drive electric vehicle includes one or more front electric motors, one or more rear electric motors, an accelerator sensor, a vehicle speed sensor, and a control unit. The one or more front electric motors are configured to directly drive front wheels. The one or more rear electric motors are configured to directly drive rear wheels. The accelerator sensor is configured to determine an operation amount of an accelerator. The vehicle speed sensor is configured to determine vehicle speed. The control unit is configured to control drive of the one or more front and rear electric motors based on the operation amount of the accelerator and the vehicle speed. The control unit is configured to change an allocation of driving force between the one or more front electric motors and the one or more rear electric motors with a bias toward the rear wheels in a case where the operation amount of the accelerator is increased at or above a predetermined rate in a state in which the vehicle speed is higher than or equal to a predetermined speed.

An all-wheel-drive electric vehicle includes one or more front electric motors, one or more rear electric motors, an accelerator sensor, a vehicle speed sensor, and a control unit. The one or more front electric motors are configured to directly drive front wheels. The one or more rear electric motors are configured to directly drive rear wheels. The accelerator sensor is configured to determine an operation amount of an accelerator. The vehicle speed sensor is configured to determine vehicle speed. The control unit is configured to control drive of the one or more front and rear electric motors based on the operation amount of the accelerator and the vehicle speed. The control unit is configured to change an allocation of driving force between the one or more front electric motors and the one or more rear electric motors with a bias toward the rear wheels in a case where the operation amount of the accelerator is increased at or above a predetermined rate in a state in which the vehicle speed is higher than or equal to a predetermined speed.

A transfer for a four wheel drive vehicle includes first and second distribution mechanisms that respectively include first and second clutches configured to be controlled to a half-engaged state. The first and second distribution mechanisms distribute a portion of power outputted from a power source to a second transmission mechanism respectively through the first and second clutches. A first difference is different from a second difference. The first difference is a difference between a gear ratio from an input shaft of the first clutch to a first driving wheel and a gear ratio from an output shaft of the first clutch to a second driving wheel. The second difference is a difference between a gear ratio from an input shaft of the second clutch to the first driving wheel and a gear ratio from an output shaft of the second clutch to the second driving wheel.

A transfer for a four wheel drive vehicle includes first and second distribution mechanisms. The first distribution mechanism includes a first clutch and is configured to distribute a portion of power from a power source to a second transmission mechanism through the first clutch. The second distribution mechanism includes a planetary gear set and a second clutch, and is configured to distribute a portion of power from the power source to a second transmission mechanism through the planetary gear set and the second clutch in order. The first and second clutches are configured to be controlled to a half-engaged state between engagement and disengagement. An input shaft of the first distribution mechanism and an input shaft of the planetary gear set are unitized.

A vehicle power transfer unit assembly comprises an input shaft, an intermediate shaft at least partially surrounding the input shaft, a central shaft adjacent the input shaft, a peripheral shaft at least partially surrounding the central shaft, a first shift collar, and a second shift collar. The first shift collar is operable between a first position where torque is transferred from the input shaft to the intermediate shaft and a second position where torque is not transferred from the input shaft to the intermediate shaft. The second shift collar is operable between a third position where torque is transferred from the input shaft to the peripheral shaft and a fourth position where torque is transferred from the input shaft to the central shaft.

The invention includes first and second motors, first and second differential mechanisms, and first to eighth decoupling mechanisms. The first and second motors transmit power to left and right wheels. First differential mechanisms distribute the power from the first and second motors. The first and second mechanisms are interposed between the first differential mechanism and the left front wheel and between the differential mechanism and the left rear wheel. The third and fourth decoupling mechanisms are interposed between the first motor and the first decoupling mechanism and between the first motor and the second decoupling mechanism. The fifth and sixth decoupling mechanisms are interposed between the second differential mechanism and the right front wheel and the right rear wheel, respectively. The seventh and eighth decoupling mechanisms are interposed between the second motor and the fifth decoupling mechanism and between the second motor and the sixth decoupling mechanism.

A transfer for a four wheel drive vehicle includes first and second distribution mechanisms that respectively include first and second clutches configured to be controlled to a half-engaged state. The first and second distribution mechanisms distribute a portion of power outputted from a power source to a second transmission mechanism respectively through the first and second clutches. A first difference is different from a second difference. The first difference is a difference between a gear ratio from an input shaft of the first clutch to a first driving wheel and a gear ratio from an output shaft of the first clutch to a second driving wheel. The second difference is a difference between a gear ratio from an input shaft of the second clutch to the first driving wheel and a gear ratio from an output shaft of the second clutch to the second driving wheel.

An axle including a housing having a first cavity and a second cavity formed therein. The first cavity is configured to receive at least a portion of an axle assembly therein, and the second cavity is configured to receive at least a portion of a power source assembly therein.

By driving a first electromagnetic solenoid and a second electromagnetic solenoid, if first cams of a first thrust force amplification mechanism and a second thrust force amplification mechanism are connected to non-rotary members, since second cams are rotated at rotating speeds that are proportional to a vehicle speed V, the relative rotations between the first cam and the second cam increase. Therefore, the first thrust force amplification mechanism and the second thrust force amplification mechanism can be actuated quickly, to thereby switch connection/disconnection states of the first connection/disconnection mechanism and the second connection/disconnection mechanism quickly.

A driving force distributing device includes a single pump for supplying control hydraulic pressure to each of first and second hydraulic clutches, an electric motor for driving the pump, a flow rate variable mechanism for changing a ratio of flow rate of hydraulic fluid supplied to each of the first and second hydraulic clutches and a controlling means for controlling the electric motor and the flow rate variable mechanism. The driving force distributing device can variably control a flow rate of hydraulic fluid supplied to first and second hydraulic clutches based on changing a ratio of flow rate of hydraulic fluid supplied to the first and second hydraulic clutches in the flow rate variable mechanism and a control of changing rotational speed of the pump using the motor.