A power transmission device include: a differential having three rotational elements; and a connection switching device that selectively switches a connection relationship among an input shaft, a first output shaft, a second output shaft, and the three rotational elements. Further, the connection switching device selectively fixes any one rotational element to a fixing member, the second power source is coupled to rotational elements other than the rotational element fixed to the fixing member, the differential can be switched between modes including a first mode where any one rotational element among the three rotational elements is coupled to the input shaft, one of the remaining rotational elements is fixed to the fixing member, and the other is coupled to the first output shaft, and a second mode where the three rotational elements are respectively coupled to the second power source, the first output shaft, and the second output shaft.

A work vehicle including an articulated vehicle chassis having a front frame portion and a rear frame portion pivotally coupled together at a generally vertical pivot axis. The front frame portion carries a front axle and the rear frame portion carries a rear axle. A steering system includes at least one steering cylinder connected between the front frame portion and the rear frame portion. A power plant provides motive power to the work vehicle, and a transmission receives power from the power plant and provides power to the front axle and rear axle. The work vehicle further includes a secondary clutch interconnected between the transmission and the rear axle. The steering system is configured to disengage the secondary clutch to provide reactive steering, whereby the front frame portion tows the rear frame portion. The rear frame portion freely articulates relative to the front frame portion.

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.

A control device is to be applied to a four-wheel drive vehicle including a first coupling device interposed between a rear-wheel final gear device and a rear left wheel axle and a second coupling device interposed between the rear-wheel final gear device and a rear right wheel axle. The control device includes a controller changes a coupling torque of the first coupling device and a coupling torque of the second coupling device independently of each other. The controller estimates, when the vehicle is accelerating, a vehicle body speed of the vehicle under a state in which the coupling torque of any one of the first coupling device and the second coupling device is set to a value larger than zero and the coupling torque of another one thereof is set to zero. Thereby, the control device can accurately estimate the vehicle body speed when the vehicle is traveling while accelerating.

A vehicle caravan comprising electric vehicles configured for coordinated movement and airflow control comprising: a lead vehicle and chase vehicle, the lead vehicle disposed at the front of the caravan and the chase vehicle disposed behind the lead vehicle in a chase pattern. Each lead and chase vehicle comprising: a vehicle chassis and a front rotatable vehicle drive axle; a selectively movable electric propulsion motor comprising a rotatable motor shaft and motor axis configured to be oriented in a substantially vertical direction; an air duct configured to direct an airflow to the propulsion motor; an airflow shutter in the front end of the air duct to selectively control the airflow within the air duct; and a vehicle controller; the caravan and chase pattern configured for coordination of the motor position and the open/closed position of the lead and chase vehicle shutters while the caravan is moving.

Fluid control apparatus for use with vehicle clutches are disclosed. A disclosed clutch coupling assembly for a vehicle includes a housing defining a cavity. The clutch coupling assembly also includes a fluid reservoir fluidly coupled to the cavity. The clutch coupling assembly also includes a clutch positioned in the cavity. Rotation of the clutch is to convey a fluid from the cavity to the fluid reservoir. The clutch coupling assembly also includes a pump operatively coupled to the housing to control the fluid. Operation of the pump is to convey the fluid from the fluid reservoir to the cavity when the clutch is in an engaged state.

A drive force control system for a vehicle configured to allow a driver to find out a steering angle at which a wheel grips a road surface. In the vehicle, a torque distribution ratio to a pair of wheels turned by a steering wheel and another pair of wheels is changeable. A controller restricts a control to change the torque distribution ratio in the event of a slip of the pair of wheels, if a steering angle of the pair of wheels is changed to allow the pair of wheels to grip a road surface.

Systems, apparatus, and methods to control fluid associated with vehicle clutches are disclosed. A disclosed apparatus includes a drive unit assembly for a vehicle. The drive unit assembly includes a housing and a clutch in a cavity of the housing. Rotation of a drum of the clutch expels a fluid from the cavity. The apparatus also includes a vehicle controller configured to disengage the clutch via an actuator. Actuation of the actuator reduces a flow of the fluid into the cavity. The vehicle controller is also configured to maintain engagement of a vehicle transfer device operatively coupled between a vehicle transmission and the drum such that the drum continues to rotate for a time interval during which the clutch is disengaged.

A control apparatus configured to control a driving force transmission apparatus. The control apparatus includes a torque command value calculator configured to calculate a torque command value for the right and left rear wheels based on a front-rear wheel rotation speed difference, a command value limiter configured to limit the torque command value to a value equal to or smaller than an upper limit value, and a current controller configured to control a current to be supplied to the driving force transmission apparatus so that a driving force determined based on the torque command value is transmitted to the right and left rear wheels. When the front-rear wheel rotation speed difference increases, the command value limiter sets the upper limit value smaller as a change amount of the front-rear wheel rotation speed difference per unit time increases.

A drive device includes a first clutch mechanism that couples or decouples power transmission systems for front and rear wheels, a first electric motor disposed on a front or rear wheel side and coupled to the first clutch mechanism, a second electric motor disposed on the other of the front and rear wheel sides and coupled to the first clutch mechanism, a second clutch mechanism that couples or decouples the first electric motor and front drive shafts, a planetary gear mechanism that distributes output of the first electric motor to the first and second clutch mechanisms, and a third clutch mechanism that limits, in the planetary gear mechanism, a difference between a first rotational element that transmits the output of the first electric motor to the first clutch mechanism and a second rotational element that transmits the output of the first electric motor to the second clutch mechanism.