Disclosed is a travel control apparatus applied to a vehicle which includes two coupling apparatuses individually changing coupling torques between a drive output part for secondary drive wheels and left and right secondary drive wheel axles and in which the ratio of rotational speed of the drive output part to the average of rotational speeds of primary drive wheels is greater than 1. The apparatus generates a yaw moment in a turning direction by using driving force. When a demand of further increasing the yaw moment arises, the control apparatus renders the braking force of the primary drive wheel on the turning locus inner side coincident with a target braking force changing with the travel state of the vehicle and decreases the coupling torque of the coupling apparatus corresponding to the secondary drive wheel on the turning locus outer side. As a result, generation of an anti-spin moment is avoided.

A control device is mountable on a four-wheel drive vehicle including a main drive wheel and an auxiliary drive wheel, and is configured to control a drive force transmission device configured to transmit a drive force to the auxiliary drive wheel. The control device includes a processor and a memory storing a program, when executed by the processor, to cause the control device to change a control characteristic of the drive force transmission device that indicates a relationship between a vehicle state of the four-wheel drive vehicle and a drive force transmitted to the auxiliary drive wheel in response to an input from the input device.

A power transmission device is provided, which includes a main-drive-wheel drive part, and an auxiliary-drive-wheel drive part having a power extraction part which has a transfer gear set comprised of a transfer drive gear connected to the main-drive-wheel drive part and a transfer driven gear meshing with the transfer drive gear and configured to transmit power to the auxiliary drive wheels. In a power transmission path from the main-drive-wheel drive part to the transfer drive gear, an input shaft connected to the main-drive-wheel drive part and a power transmission shaft connected to the transfer drive gear are coupled to each other in a radial direction through a first spline having a first backlash. A first shear damper without backlash and a second shear damper provided with a second spline having a second backlash smaller than the first backlash are provided between the input shaft and the power transmission shaft.

In an all-wheel drive (AWD) vehicle, torque carrying connections are provided between the powertrain and all four wheels. A multimode clutch module or clutches are provided to selectively disconnect two of the wheels from the powertrain during operating conditions where disconnection improves the performance and efficiency of the AWD vehicle. The multimode clutch module may be installed at various locations of the AWD vehicle, such as within a front or rear differential, between a half axle and a differential or between a half axle and a corresponding wheel, or within a transfer case or power transfer unit.

The drive power connecting/disconnecting device includes a second shaft disposed coaxially to a first shaft so as to transmit drive power to a wheel axle, a connection/disconnection member which moves a second rotational body along an axial direction with respect to a first rotational body, and which is capable of moving in the axial direction so as to make or break engagement between the first shaft and the second shaft, a supporting member, a shaft cover which covers at least the periphery of the second rotational body, a first pivotally supporting portion which is disposed between the first shaft and the second shaft so as to axially support one end of the second shaft; and a second pivotally supporting portion which is disposed inside the shaft cover so as to axially support the other end of the second shaft.

A drive force transmission apparatus is mountable on a four-wheel drive vehicle switchable between a four-wheel drive mode that transmits a drive force of an engine to front wheels and rear wheels, and a two-wheel drive mode that transmits the drive force to only the front wheels. The drive force transmission apparatus allows adjustment of the drive force to the rear wheels, and includes a multi-plate clutch, a piston for axially pressing the multi-plate clutch, an actuator for axially moving the piston, and a control unit for controlling the actuator. Upon satisfaction of a predetermined condition that indicates a high probability of the vehicle needing to be switched from the two-wheel drive mode to the four-wheel drive mode, the control unit causes the actuator to displace the piston by a predetermined amount with respect to an initial position of the piston toward the multi-plate clutch.

A method for controlling a vehicle including a main transmission and a hydraulic transmission, in which, in the absence of a setpoint on the brake, and when the hydraulic transmission is activated, a hydraulic pump of the hydraulic transmission is controlled in such a way as to establish a predetermined pressure inside a hydraulic circuit of the hydraulic transmission, and in the event of a setpoint applied to the brake, the hydraulic transmission is then controlled according to an acceleration setpoint applied to the vehicle. If the acceleration setpoint is greater than or equal to an acceleration threshold value, and the speed of travel of the vehicle is less than or equal to a speed threshold value, the hydraulic transmission is controlled in such a way as to apply a tractive force. If the acceleration setpoint is less than the first threshold value, the hydraulic transmission is disengaged.

A method for determining a contact force on a utility vehicle includes providing the utility vehicle with a first wheel axle and a second wheel axle, determining a drive slip of the second wheel axle, and a road surface-specific determination data set associated with a traction coefficient in dependence on the drive slip, and determining the contact force on the second wheel axle based on the drive slip of the second wheel axle and the road surface-specific determination data set.

A method for controlling the safe operation of a rear axle of a set of combined axles powered by a motor vehicle, particularly for a vehicle designed to carry loads and which have 6×4, 8×4 or 10×4 type traction configurations, or tridem models formed by three drive axles. The method includes a set of steps and activities that ensure proper and safe operation of systems and mechanisms for uncoupling and raising a rear axle of a vehicle, and more specifically checking a status of certain operating parameters of the rear axle and of the vehicle itself in order to permit or prevent uncoupling and coupling, as well as raising and lowering of the rear axle of the vehicle.

A vehicle driving-force distributing device includes: first connecting/disconnecting teeth disposed on the inner circumferential side of the ring gear; a connecting/disconnecting mechanism that includes a cylindrical member and a connecting/disconnecting sleeve including second connecting/disconnecting teeth and spline-fitted movably in the rotation axis direction and relatively non-rotatably to the outer circumferential side of the shaft insertion portion and that connects and disconnects a power transmission path between the ring gear and the differential case by moving the connecting/disconnecting sleeve in the rotation axis direction between a meshing position at which the second connecting/disconnecting teeth are meshed with the first connecting/disconnecting teeth and a non-meshing position at which the second connecting/disconnecting teeth are not meshed with the first connecting/disconnecting teeth; and a synchronizing mechanism disposed between the ring gear and the cylindrical member and reducing a relative rotation between the first connecting/disconnecting teeth and the second connecting/disconnecting teeth.