Abstract: A front wheel is placed on a lifting table, which is rotated by an actuator together with the front wheel. By rotating the lifting table by the actuator, the front wheel is rotated under constraint of a steering mechanism of an automobile. The rotation angle of an arm with respect to a base is detected by an encoder provided at an end of an extendable rod which pivotally supports the arm in a rotatable manner. The rotation angle of the base is detected by a second encoder to determine the rotation angle ?2??1 and rotation radius Lt of the front wheel under constraint of the steering mechanism. Based on reaction force F detected by a load cell, rotation radius Lt, and rotation angle ?2??1, friction torque Tt is determined.

Abstract: A system for transmitting power to vehicle wheels includes a transmission output connected to a first wheel set, a planetary gearset including an input and an output, whose speed is greater than a speed of the gearset input, and a coupler having a variable torque capacity, driveably connecting the transmission output and the gearset input.

Abstract: A vehicle that includes front and rear wheels, an engine, an engine-driven rear angle drive for supplying torque to the rear wheels, and a power train for supplying torque from the engine to the front wheels. The power train includes driving and driven members and a coupler having an actuator switchable between on and off positions, the actuator, when off, permitting the driven member to turn freely and independently of the driving member and, when on, enabling the coupler to respond to predetermined minimum differences in rotational speed between the driving and driven members to lock these members together to rotationally couple the engine to at least one of the front wheels.

Abstract: The invention relates to a propulsion system for all-wheel drive motor vehicles, having a device for propulsion distribution to the front and the rear differential which transmit the drive output to the wheels assigned at the time, and with a device for coupled, variable distribution of the propulsion forces in the transverse and longitudinal directions of the vehicle depending on the operating situation of the vehicle for influencing the driving behavior, especially for improving the driving agility and driving stability.

Abstract: A method for controlling operation of a transfer case in a motor vehicle driveline that includes by an engine controlled by a throttle having a variable position, and a transmission driveably connected to the engine for producing multiple ratios of the speed of a transmission input relative to the speed of a transmission output. The transfer case transmitting rotating power in response to an electric signal applied to a clutch. The method includes determining that the engine throttle position is less than a first reference throttle position during a period of predetermined length; determining that a speed of the vehicle speed is in a predetermined range; determining that the transmission is operating in a speed ratio greater than a reference speed ratio; determining that the engine throttle position is greater than a first reference throttle position; and increasing the torque capacity of the clutch for a predetermined period.

Abstract: A hydro-static transmission travel system for a working machine enables the working machine to travel over a range from low speed to high speed with a simplified circuit arrangement. By referring to a machine traveling speed (vehicle speed) based on a detected signal from a rotation sensor, a controller computes respective target tilting amounts of hydraulic motors 10, 20 and controls the tilting amount for the hydraulic motors and a clutch. Depending on whether the traveling speed exceeds a setting speed as a reference boundary, the controller selectively switches over a drive mode between low-speed four-wheel drive, in which travel units 12, 22 are both driven, and high-speed two-wheel drive, in which the front-wheel side hydraulic motor 10 is controlled to zero displacement and only the rear-wheel side travel unit 22 is driven.

Abstract: Presented herein are four-wheel drive systems incorporating a bi-directional overrunning clutch design to control the torque transmission between front and rear transaxles. In accordance with one aspect of the present invention, there is provided a four-wheel drive system comprising a front transaxle, a rear transaxle, a transmission receiving drive power from a prime mover, and a bi-directional overrunning clutch drivingly coupled to an output shaft of the transmission and selectively coupled to the front and rear transaxle.

Abstract: To maintain operating safety by driving force distribution control system when an abnormal state arises and to smoothly transition from a normal state to an abnormal state without sudden changes in vehicle behavior. The driving force distribution control part calculates the transfer torque for the transfer clutch for the center differential device and the torque movement for the hydraulic motor for the rear wheel final reduction gear. When the control state detection part detects an abnormal state, there is control of the hydraulic motor in the direction that torque movement is lost on the one hand, and the transfer torque for the transfer clutch is controlled in the direction of front and rear distribution; after a preset time and after this control is carried out, the transfer torque drops.

Abstract: The invention relates to a drive unit for motor vehicles, comprising an internal combustion engine, a transmission which is mounted downstream therefrom and is provided with an integrated differential, and a separating clutch that is disposed between the internal combustion engine and the transmission. The differential is driven via a bevel wheel and a bevel-gear drive comprising a drive pinion on an output shaft of the transmission. In order to create a drive unit that is advantageous regarding structure and efficiency, the bevel wheel (48) of the differential (16) is placed laterally from the separating clutch (26) from a vertical perspective and partly protrudes (A) therefrom in an axial direction.

Abstract: A power train for a vehicle includes a gearbox with an input shaft and an output shaft and is configured such that the input shaft drives the output shaft at a single speed ratio in a first direction and a single speed ratio in a second direction. The output shaft is coupleable with the front and rear vehicle axles to separately drive each axle. Further, a continuously variable transmission is connected with an engine shaft and with the gearbox input shaft such that the engine shaft drives the input shaft within a range of speed ratios from less than 1 to greater than 3. Front and rear differentials are coupled with each axle and with the output shaft and drive the axles at different speed ratios such that a base surface drives the front axle independently of the front differential when at least one rear wheel rolls upon the surface.

Abstract: A vehicle with primary and secondary drivelines and a power take-off unit (PTU). The primary driveline has a first differential that is configured to distribute power to a first set of wheels. The PTU has a PTU input, a PTU output and a synchronizer for selectively de-coupling the PTU output from the PTU input. The secondary driveline is configured to distribute power to a second set of wheels and has a propshaft, a second differential, a pair of half-shafts and at least one torque transfer device (TTD). The propshaft transmits rotary power between the PTU output and an input of the second differential. The half-shafts are rotatably coupled to an output of the second differential and are configured to transmit rotary power to the second set of wheels. The at least one TTD is configured to selectively inhibit torque transmission through the second differential to the second set of wheels.

Abstract: A vehicle drive control for a wheeled vehicle including a first motor generator, and a second motor generator. A planetary gear set includes a first rotating element connected to the first motor generator, a second rotating element connected to the second motor generator, and a third rotating element connected to a drive wheel. A rotation control mechanism selectively restricts rotation of one of the first and second rotating elements of the planetary gear set to establish a fixed speed ratio mode, and releases the one of the first and second rotating elements to establish a variable speed ratio mode. A control unit is configured to control each operating state of the rotation control mechanism, the first motor generator, and the second motor generator, and configured to establish the variable speed ratio mode when a slip state of the drive wheel is detected in the fixed speed ratio mode.

Abstract: A turning control apparatus for a vehicle with improved turning ability and that avoids degradation of acceleration ability is provided. The turning control apparatus comprises: a driving torque controller (31) for adjusting driving torque between a left and right wheels (14L and 14R); a unit(41) for setting a basic-driving-torque-difference value indicating a difference of the driving torque between the left and right wheels (14L and 14R); a unit (42) for obtaining an acceleration/deceleration value indicating a degree of acceleration/deceleration of the vehicle; and a unit (43) for adjusting the basic-driving-torque-difference value, as a target driving torque difference, according to the acceleration/deceleration value and the velocity of the vehicle sensed. The driving torque controller (31) adjusts the driving torque between the left and right wheels (14L and 14R) according to the target driving torque obtained by the basic-driving-torque-difference value adjusting unit (43).

Abstract: A limited slip differential for a vehicle includes an engine, a transmission, a differential mechanism operable to distribute an output from the engine which is transmitted by way of the transmission to one of a pair of left and right front wheels and a pair of left and right rear wheels, a transfer mechanism which is disposed closer to a center of the vehicle in the left-right direction than the differential mechanism, and a distribution controller operable to control amounts of distributed outputs. The differential mechanism is disposed in a first side of the transfer mechanism. The distribution controller is disposed in a second side of the transfer mechanism which is opposite to the first side, and includes a clutch mechanism operable to limit a differential action between the one of the drive shafts and the output shaft.

Abstract: A method for transmitting power to the wheels of a motor vehicle includes driveably connecting an output of a transmission to a first set of wheels, varying the magnitude of torque transmitted to an input of a differential mechanism, varying the speed of the input of the first differential mechanism, and driveably connecting the differential mechanism to the wheels of a second wheel set.

Abstract: A method for automatically actuating longitudinal blocks in four-wheel vehicles, particularly in working machines and service vehicles. The longitudinal blocks are always open when driving situations occur in which the blocking effect is absolutely unnecessary. The longitudinal blocks are closed in all other situations.

Abstract: A driving force distribution control unit 60 calculates front/rear driving force distribution cooperative control addition yaw moment by multiplying front/rear driving force distribution control addition yaw moment by a front/rear driving force distribution cooperative control gain. Under steering accelerating condition, when it is possible to judge that actual lateral acceleration is high and the road is a high ? road, the front/rear driving force distribution cooperative control gain is set to become a low control gain so as to reduce a control amount by the front/rear driving force distribution control operation. Also, the driving force distribution control unit 60 calculates right/left driving force distribution cooperative control addition yaw moment by multiplying right/left driving force distribution control addition yaw moment by a right/left driving force distribution cooperative control gain.

Abstract: A method for transmitting power to the wheels of a motor vehicle includes driveably connecting an output of a transmission to a first set of wheels, varying the magnitude of torque transmitted to an input of a differential mechanism, varying the speed of the input of the first differential mechanism, and driveably connecting the differential mechanism to the wheels of a second wheel set.

Abstract: A hydraulic system for a work vehicle including a manifold assembly configured to prioritize hydraulic fluid flow to priority functions over a wide range of engine speeds.

Abstract: A torque transfer device in a motor vehicle, used for variable transfer of torque from a first shaft associated with a first wheel pair to a second shaft associated with a second wheel pair. A coupling unit facilitates variable torque-transferring coupling of the first and second shaft. The coupling unit has a first coupling element rotationally connected to the first shaft and a second coupling element connected to the second shaft. The elements cooperate with each other or are capable of cooperating with each other in order to transfer torque. A controllable adjusting device adjusts a strength of the interaction between the coupling elements by adjusting a relative position and/or a mechanical contact pressure. A control device controls the adjustment. The control device includes a data processing unit for calculating a first control signal on the basis of a plurality of input signals according to predefined rules and for controlling the adjusting device.

Abstract: A bi-directional clutch to be equipped on a vehicle, which is selectively automatically clutched off for putting the vehicle into a two-wheel drive mode or clutched on for putting the vehicle into a four-wheel drive mode, in correspondence to a condition of the vehicle during either forward traveling or backward traveling. The invention also relates to a vehicle equipped with the bi-directional clutch.

Abstract: An IG-off-timer measures the time t_off from when an engine is stopped, or an ignition is turned off. An ECU sequentially memorizes an estimated temperature of each of heat generating portions as a memorized temperature. Immediately after the engine is re-started, the ECU sets an initial value of the estimated temperature of each heat generating portion in such a manner that the initial value reflects a temperature drop of the heat generating portion in the deactivation period of the engine. The temperature of the heat generating portion is thus accurately estimated even after re-starting of the engine. The heat generating portions are thus appropriately protected.

Abstract: A four-wheel-drive vehicle transmission (1) having a drive torque input shaft (8) rotated about a first axis of rotation (A); a front output shaft (10); a rear output shaft (12); an auxiliary tubular shaft (14) mounted alongside the input shaft (8) to rotate about a second axis of rotation (D); at least one first group of gears (15, 16) for selectively connecting the auxiliary tubular shaft (14) to the input shaft (8); a first countershaft (17) mounted inside the auxiliary tubular shaft (14); a second countershaft (18) mounted for rotation opposite the first countershaft (17); a planetary gear train (19) for mechanically connecting the auxiliary tubular shaft (14) to the first (17) and second (18) countershafts; and a first (25) and a second (26) cascade gear set for connecting the first and second countershafts (17,18) to the front and rear output shafts (10,12), respectively.

Abstract: An apparatus for controlling the driving force of a vehicle is capable of using brakes to limit a differential operation, securing sufficient torque, and suppressing the heating and wearing of the brakes. In the vehicle, an engine generates torque to drive front wheels and/or rear wheels. A front differential allows differential rotation between the front wheels and transmits torque of the engine to the front wheels. A rear differential allows differential rotation between the rear wheels and transmits torque of the engine to the rear wheels. Disk brakes separately brake the front and rear wheels. An ABS/attitude electric control unit controls the disk brakes to limit differential rotation between the front wheels or between the rear wheels. At least one of the front and rear differentials is provided with a differential limiting mechanism.

Abstract: A drivetrain for an all-wheel drive motor vehicle which includes a longitudinally arranged central transmission, a transfer box, a Cardan shaft and two drive axles arranged normal to the direction of travel. The transfer box includes a central differential, an input and two output shafts. The input shaft of the central transmission communicates with an engine crankshaft. The transfer box input shaft is connected to an output shaft and an input element of the central differential. The first output shaft of the transfer box is connected to a first output element of the central differential and the first drive axle. The second outputt shaft of the transfer box is actively connected to a second output element of the central differential and to the second drive axle.

Abstract: The drive train of an all-wheel drive vehicle comprises a transfer case that is connected to the motor block, a driven front axle, a driven rear axle, drive shafts and a control device. To vary the torque distribution between the axles from 0 to 100% the transfer case has a drive-through shaft that has a drive connection both with the motor block and the drive shaft that leads to the rear axle. The drive-through shaft includes a drive connection with the drive shaft that leads to the front axle by a first friction clutch that determines the torque applied to the front axle. The rear axle is equipped with an additional adjustable drive unit comprising a second friction clutch, which is used to control the torque applied to the rear axle.

Abstract: A vehicle includes a wheel speed sensor sensing a vehicle speed V, a 2WD/4WD switch operative to input an instruction to switch between a two-wheel driving state and a four-wheel driving state, a transfer and an actuator switching the two-wheel driving state and the four-wheel driving state, and an ECU driving the actuator. The ECU instructs the actuator to switch from the four-wheel driving state to the two-wheel driving state regardless of the switching instruction from the 2WD/4WD switch if the vehicle tows a trailer and runs in the four-wheel driving state when the vehicle speed exceeds a predetermined value. Consequently, it is possible to provide a four-wheel drive vehicle capable of running while towing an object and also avoiding an increase in the size of the peripheral parts of driving wheels.

Abstract: A hybrid motor vehicle (10) has a four wheel drive arrangement in which the front wheels (12 and 13) are driven by the engine (11) in two wheel drive mode and all four wheels (12-15) in four wheel drive mode. The engine is connected to the rear wheels (14 and 15) through an auxiliary driveline which includes a first clutch (22) to connect to the engine (11), a propshaft (23) and a differential (25). An electric motor (28) is connected to the propshaft (23) for the purpose of driving the vehicle either with or without the assistance of the engine (11). A second clutch (27) is located between the propshaft (23) and the differential (25). When the vehicle is in two wheel drive mode, the propshaft (23) is disconnected from both the engine (11) and the rear wheels (14 and 15) and on switching to four wheel drive mode when the vehicle is moving the propshaft (23) is firstly spun up to a speed matching that of the engine (11) and rear wheels (14, 15) by the action of the electric motor (28).

Abstract: In a driving-force distribution control unit, a first transfer-torque calculation unit calculates an input-torque sensitive transfer torque, a second transfer-torque calculation unit calculates a steering-angle/yaw-rate sensitive transfer torque, and a third transfer-torque calculation unit calculates a tack-in preventing transfer torque. In the third transfer-torque calculation unit, tack-in prevention control is performed during turning at a high speed not only when the accelerator opening is substantially reduced and the current accelerator opening becomes small, but also when the torque amount to be reduced by a traction control unit is more than a preset value. Further, when at least one of a side-slip prevention control unit and an ABS is started, tack-in prevention control is prohibited.

Abstract: A system for transmitting rotary power to the wheels of a motor vehicle includes an input, a planetary final drive connected driveably to the input and including a first output that is driven at a speed that is slower than a speed of the input, and a inter-wheel planetary differential driveably connected to the first output for splitting torque carried by the first output between a second output connected driveably to a first wheel of a first wheel set and a third output connected driveably to a second wheel of the first wheel set.

Abstract: A transfer mechanism distributes drive power from a drive power source of a motor vehicle to left and right front wheels and left and right rear wheels of the vehicle. A rear differential mechanism transfers the drive power to the left and right rear wheels. A clutch is provided between the rear differential mechanism and each of the left and right rear wheels. A control device independently controls an engaged state of each of the clutches. A speed-increasing mechanism sets revolution speeds of an output shaft of the transfer mechanism and of an input shaft of the rear differential mechanism to be the same and sets a speed of the outer circumference of the rear wheel to which the drive power is transferred, via an engaged clutch, to be faster than a speed of the outer circumference of the left and right front wheels.

Abstract: A method for fore-aft stabilization of a vehicle for motion in a specified direction over an underlying surface. The vehicle has at least one forward wheel and at least one aft wheel, and the forward wheel is characterized by a force normal to the instantaneous direction of motion of the vehicle. A motor actuator drives each aft wheel, and a controller governs the motor actuator or motor actuators in such a manner as to dynamically stabilize the vehicle, according to a uniform control law, when the forward wheel is in contact with the underlying surface or not. A torque is applied to the aft wheel on the basis of vehicle pitch or the force on the forward wheel normal to the direction of motion. Additionally, a periodic rotational modulation may be applied to the aft wheel, and a stabilizing torque provided based on a detected response, either of vehicle pitch or of normal force on the front wheel.

Abstract: A drive axle assembly includes a pair of axleshafts connected to a pair of wheels, and a drive mechanism for selectively coupling a driven input shaft to one or both of the axleshafts. The drive mechanism includes first and second drive units that can be selectively engaged to control the magnitude of the drive torque transferred and the relative rotary speed between the input shaft and the axleshafts. Each drive unit includes a planetary gearset disposed between the input shaft and its corresponding axleshaft, and a pair of mode clutches that may be activated to cause the planetary gearset to establish different speed ratio drive connections between the input shaft and the axleshaft. A control system including an electronic control unit (ECU) and sensors are provided to control actuation of the clutches so as to control the side-to-side traction characteristics of the drive axle assembly.

Abstract: A transmission unit (7) with a housing (9), a transmission input shaft (10) and three transmission output shafts (11, 12, 13), at least two planetary gearsets (14, 15) and a device (16) arranged between two actively interconnected shafts (14A, 15A) of the planetary gearsets for variable distribution of torque delivered by the transmission input shaft between two of the three transmission output shafts is described. A web (14D) of the first planetary gearset is formed with a differential cage (19A) of a differential (19), which is provided in order to distribute part of the torque which is delivered by the transmission shaft that has been passed on to the two of the transmission output shafts between the two transmission output shafts.

Abstract: A vehicle include a first disconnect disposed between a prime mover of the vehicle and a certain one of the vehicle drive wheels. The first disconnect is operable to connect and disconnect the prime mover to and from the certain one of the drive wheels. A second disconnect is disposed between the powertrain and the certain one of the drive wheels, and is operable to connect and disconnect the certain one of the drive wheels to and from the powertrain when the first disconnect is engaged. A control system and method are configured to control operation of at least the first and second disconnects. Through selective control of the disconnects, the system can be automatically placed in a four-wheel-drive mode based on predetermined criteria, or the desirability of the four-wheel-drive mode can be indicated to the vehicle operator in a passive version of the control system and method.

Abstract: A drive axle assembly includes first and second axleshafts and a drive mechanism coupling a driven input shaft to the axleshafts. The drive mechanism includes a differential assembly, a planetary gear assembly operably disposed between the differential assembly and the first axleshaft, a brake and first and second mode clutches. The first clutch is operable with the brake and the planetary gear assembly to increase the rotary speed of the first axleshaft which, in turn, causes a corresponding decrease in the rotary speed of the second axleshaft. The second clutch is operable with the brakes and the planetary gear assembly to decrease the rotary speed of the first axleshaft so as to cause an increase in the rotary speed of the second axleshaft. A control system controls actuation of both mode clutches.

Abstract: An on demand vehicle drive system monitors vehicle performance and operating conditions and controls torque delivery to the vehicle wheels. The system includes a plurality of speed and position sensors, a transfer case having primary and secondary output shafts driving primary and secondary axles and a microcontroller. The sensors include a vehicle speed sensor, a pair of primary and secondary drive shaft speed sensors, and brake and driveline status sensors. The transfer case includes a modulating electromagnetic clutch controlled by the microcontroller which is incrementally engaged to transfer torque from the primary output shaft to the secondary output shaft. When the speed of either the front or the rear drive shafts overruns, i.e., exceeds, the speed of the other drive shaft by a predetermined value related to the vehicle speed, indicating that wheel slip is present, clutch current is incrementally increased to increase clutch engagement and torque transfer to the secondary axle.

Abstract: A control device for a four-wheel drive vehicle, including: a yaw moment control unit for selecting and applying to a wheel based on a driving state a braking force to generate vehicular yaw moment; a driving force control unit for identifying and reducing excess driving force based on the driving state; a limited slip differential control unit for limiting a front wheel differential; a front/rear driving force distribution control unit for controlling engagement torque of a clutch unit which varies front/rear torque distribution via a center differential; and a switch unit for selecting an operation/non-operation of the driving force control unit, wherein the front/rear driving force distribution control unit sets the engagement torque at a greater value when the yaw moment control unit operates while the driving force control unit is non-operating, than when the yaw moment control operates while the driving force control unit is operating.

Abstract: A method for the readjustment of an actuator of an all-wheel drive clutch of a motor vehicle that includes determining a clutch slip value corresponding to a difference between the speed of a primary axle and the speed of a secondary axle; determining a reference secondary axle torque corresponding to the proportion of a driving torque which is transmitted to the secondary axle and for which a clutch slip value of substantially zero is expected; and comparing the clutch slip value with a threshold value and comparing a desired clutch torque with the reference secondary axle torque. A desired clutch torque/control signal relationship for the clutch actuator is changed in dependence on the result of these comparisons.

Abstract: A four-wheel drive system for a hybrid vehicle includes at least two motor-generators and a single engine connected to a differential having multiple degrees of freedom. In some embodiments, by adjusting the outputs of the motor-generators, a controller allocates power from the engine, to or from each of the motor-generators, to the front wheels and to the rear wheels, each of which is connected to an element of the differential. The relationship between the elements of the differential is represented by an alignment chart of the differential.

Abstract: An all-wheel drive motor vehicle having at least two wheel axles and comprising an electrical or hydraulic drive unit having a plurality of electric or hydraulic motors connected to an electrical or hydraulic energy source. Each motor is associated with a drive wheel and drives such wheel via a transmission. The motors that are associated with a given one of the wheel axles are adapted to be coupled with one another via a shiftable transverse locking device. At least one of the motors on a first side of the vehicle is adapted to be coupled, via a shiftable longitudinal locking device, with one of the motors associated with a different one of the wheel axles on the same side or on a second side of the vehicle.

Abstract: In a four-wheel drive motor vehicle with a primary drive axle and a secondary drive axle, at least one secondary drive axle coupling of the limited slip type is provided in the powertrain between the engine of the vehicle and the secondary drive axle. A primary drive axle coupling of the limited slip type is provided for the primary drive axle.

Abstract: A distribution ratio determining unit determines the distribution ratio for distributing a required torque based on a static load distribution ratio, when the sign of the required torque is negative. The distribution ratio determining unit determines the distribution ratio based on a dynamic load distribution ratio, when the sign of the required torque is positive. The distribution ratio determining unit determines the distribution ratio based on the static load distribution ratio and the dynamic load distribution ratio, when the sign of the required torque changes. Thus, even when the sign of the required torque changes, it is possible to prevent the driving forces for a plurality of wheels of a vehicle from changing discontinuously.

Abstract: An engine arrangement structure of a saddle-ride type vehicle includes an engine having a crankcase and a cylinder part overhung upwardly from the crankcase. An alternating current generator is provided at one end of the crankshaft with a power transmission system member being provided at the other end thereof. The alternating current generator and the power transmission system member are overhung ahead of and behind the engine relative to the engine cylinder part, respectively. A width by which the power transmission system member is overhung is larger than that by which the alternating current generator is overhung. The alternating current generator of the engine is arranged so as to be directed to the front side of the vehicle body and the power transmission system member is arranged so as to be directed to the rear side of the vehicle body.

Abstract: An on-demand four wheel drive system for a vehicle having a front drive train, a rear drive train, and a transfer case. The system includes a sensor system operable to detect the speed of the front drive train and the speed of the rear drive train. The system also includes a controller operable to cause the transfer case to supply input torque to the front drive train and the rear drive train when the sensor system detects that the speed of the rear drive train exceeds the speed of the front drive train by a predetermined amount. The controller is further operable to cause the transfer case to limit the amount of input torque supplied to the front drive train when the sensor system detects that the speed of the front drive train exceeds the speed of the rear drive train.

Abstract: A limited slip differential for a vehicle includes an engine, a transmission, a differential mechanism operable to distribute an output from the engine which is transmitted by way of the transmission to one of a pair of left and right front wheels and a pair of left and right rear wheels, a transfer mechanism which is disposed closer to a center of the vehicle in the left-right direction than the differential mechanism, and a distribution controller operable to control amounts of distributed outputs. The differential mechanism is disposed in a first side of the transfer mechanism. The distribution controller is disposed in a second side of the transfer mechanism which is opposite to the first side, and includes a clutch mechanism operable to limit a differential action between the one of the drive shafts and the output shaft.

Abstract: Power of an engine is divided to be transmitted to a power transmission path to front wheels and a power transmission path to rear wheels by a transfer mechanism where the power has just passed through a transmission so as to be transmitted to front wheels and rear wheels. In addition, a torque reduction and transmission joint is provided on the power transmission path to the rear wheels, so that the rotational drive torque to the rear wheels is reduced to be transmitted thereto. Additionally, constant velocity joints which are provided on the power transmission path to the rear wheels are configured to have a smaller torque transmission capacity and a smaller size than those of constant velocity joints which are provided on the power transmission path to the front wheels.

Abstract: A vehicle driveline comprising a primary drive system including at least one primary drive wheel and an auxiliary drive system including at least one auxiliary drive wheel is disclosed. The vehicle driveline may further comprise a system for idling the auxiliary drive system. The system may include at least one wheel disconnect device for selectively connecting and disconnecting the auxiliary drive wheel from the auxiliary drive system and a power transfer unit for selectively engaging and disengaging the auxiliary drive system from the primary drive system. The power transfer unit may include a multi-plate clutch in series with a dog clutch.

Abstract: A vehicle slip state determination system serves to calculate an estimated vehicle speed VB, an estimated vehicle deceleration in the vehicle speed DVB, and each of wheel speed differences between right front and rear wheels and between left front and rear wheels ?VR, ?VL, respectively. The wheel speed difference ?VR, ?VL are divided into three ranges, that is, range 1, range 2, and range 3 by the speed difference upper and lower limit values JVUP and JVLO, each of which is a linear function value with respect to the estimated vehicle deceleration DVB. In the ranges 1 and 3, the vehicle traveling on the road with the low friction coefficient ? is brought into the slip state where four wheels are slipped. If the wheel speed difference at a predetermined estimated vehicle deceleration deviates from a determination range defined by the upper and lower limit values, the slip state of the vehicle, that is, the condition where the vehicle is traveling on the road with the low friction coefficient ? is determined.

Abstract: A power transfer system for four-wheel drive vehicles is provided which allows the power transmission system to be compact and the front differential to be located near the lateral center of the vehicle body even when an unmodified FR vehicle transmission is used. The amount of offset by which a pinion shaft of the front differential is offset from the lateral center of the vehicle body toward a drive pinion shaft is defined such that right and left drive shafts coupled to the front differential can be considered generally equal in length to each other. Furthermore, a differential case near the pinion shaft is extended toward the drive pinion shaft where the outer diameter thereof is maintained, and a hypoid drive gear is attached to the extended portion.