A rotary coupling (200) for an all-wheel drive vehicle includes a housing (210), an input part (212), an output part (214), and a clutch (220) disposed within a clutch area (222) of the housing (210) and is movable between an engaged position and a disengaged position to change an amount of torque transferred from the input part (212) to the output part (214). A fluid reservoir (260) is defined in the housing (210). A lubrication valve (250) is movable between an open position and a closed position for controlling supply of a fluid from the fluid reservoir (260) to the clutch area (222) of the housing (210). An actuator (238) is connected to the clutch (220) to move the clutch (220) between the engaged position and the disengaged position and connected to the lubrication valve (250) to move the lubrication valve (250) between the open position and the closed position.

A rotary coupling (200) for an all-wheel drive vehicle includes a housing (210), an input part (212), an output part (214), and a clutch (220) disposed within a clutch area (222) of the housing (210) and is movable between an engaged position and a disengaged position to change an amount of torque transferred from the input part (212) to the output part (214). A fluid reservoir (260) is defined in the housing (210). A lubrication valve (250) is movable between an open position and a closed position for controlling supply of a fluid from the fluid reservoir (260) to the clutch area (222) of the housing (210). An actuator (238) is connected to the clutch (220) to move the clutch (220) between the engaged position and the disengaged position and connected to the lubrication valve (250) to move the lubrication valve (250) between the open position and the closed position.

A utility vehicle includes a diesel engine, a two-four wheel drive switcher provided on a driving power transmission path from the diesel engine and configured to switch transmission of driving power to driving wheels between a two-wheel drive mode and a four-wheel drive mode, and a vehicle control unit configured to control the two-four wheel drive switcher. The utility vehicle further includes a rollover sensor configured to detect rollover of the utility vehicle, and a fuel cutoff valve configured to cut off fuel supply to the diesel engine. The vehicle control unit determines whether or not the utility vehicle is being rolled over in accordance with detection by the rollover sensor and controls the fuel cutoff valve to cut off the fuel supply when the vehicle control unit determines that the utility vehicle is being rolled over.

A utility vehicle includes a diesel engine, a two-four wheel drive switcher provided on a driving power transmission path from the diesel engine and configured to switch transmission of driving power to driving wheels between a two-wheel drive mode and a four-wheel drive mode, and a vehicle control unit configured to control the two-four wheel drive switcher. The utility vehicle further includes a rollover sensor configured to detect rollover of the utility vehicle, and a fuel cutoff valve configured to cut off fuel supply to the diesel engine. The vehicle control unit determines whether or not the utility vehicle is being rolled over in accordance with detection by the rollover sensor and controls the fuel cutoff valve to cut off the fuel supply when the vehicle control unit determines that the utility vehicle is being rolled over.

A method of disengaging an axle disconnect system including providing an actuator having a coil (214) at least partially surrounded by a housing (220), an armature (216) located within the housing and the coil, where the armature is capable of actuating between a first and second position, and at least one of the housing and the armature is part of a magnetic circuit. Applying a current to the coil and actuating the armature from the first position to the second position. Developing an uninterrupted magnetic flux through the magnetic circuit and stopping application of the current to the coil. Permitting the magnetic flux through the magnetic circuit to continue in its uninterrupted state and maintain the armature in the second position. Applying an alternating current, having decreasing amplitude over time, to the coil to dissipate the magnetic flux through the magnetic circuit.

A method of disengaging an axle disconnect system including providing an actuator having a coil (214) at least partially surrounded by a housing (220), an armature (216) located within the housing and the coil, where the armature is capable of actuating between a first and second position, and at least one of the housing and the armature is part of a magnetic circuit. Applying a current to the coil and actuating the armature from the first position to the second position. Developing an uninterrupted magnetic flux through the magnetic circuit and stopping application of the current to the coil. Permitting the magnetic flux through the magnetic circuit to continue in its uninterrupted state and maintain the armature in the second position. Applying an alternating current, having decreasing amplitude over time, to the coil to dissipate the magnetic flux through the magnetic circuit.

A vehicle includes an all-wheel-drive powertrain having an electric machine configured to power wheels. A controller is programmed to output a first calculated vehicle speed derived from integrating a measured longitudinal acceleration of the vehicle and output a second calculated vehicle speed based on the measured longitudinal acceleration and a speed of one of the wheels. The controller is further programmed to, responsive to a flag being present, command a speed to the electric machine that is based on the first vehicle speed to reduce wheel slip, and responsive to a flag not being present, command a speed to the electric machine that is based on the second vehicle speed to reduce wheel slip.

A method to estimate an amount of force in a clutch pack of a clutch actuation system. The method includes engaging an actuation motor to apply a set point force to the clutch pack and monitoring a position of the actuation motor when the set point force is applied. Additionally, the method includes determining one or more clutch clamping curves and one or more clutch releasing curves based on a relationship between the position of the actuation motor and an amount of torque applied by the actuation motor at position of the actuation motor. The method further includes modeling one or more frictional characteristics of the clutch actuation system and estimating an amount of clamping and releasing force within the clutch pack by using a control unit. The amount of torque applied to the clutch pack between the clutch clamping and releasing curves at the set point force is maintained.

A method to estimate an amount of force in a clutch pack of a clutch actuation system. The method includes engaging an actuation motor to apply a set point force to the clutch pack and monitoring a position of the actuation motor when the set point force is applied. Additionally, the method includes determining one or more clutch clamping curves and one or more clutch releasing curves based on a relationship between the position of the actuation motor and an amount of torque applied by the actuation motor at position of the actuation motor. The method further includes modeling one or more frictional characteristics of the clutch actuation system and estimating an amount of clamping and releasing force within the clutch pack by using a control unit. The amount of torque applied to the clutch pack between the clutch clamping and releasing curves at the set point force is maintained.

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.