Abstract: A central differential has first and second output members for distributing power of an engine through a transmission to front and rear wheels respectively, and has a third output member for controlling distribution of the power. A first friction clutch is operatively connected to the second and third output members for restricting differential operation of the central differential and for controlling distribution of the power to the front and rear wheels. A second friction clutch is operatively connected to the second output member and either of the front or rear wheels. The first friction clutch is disposed at the innermost position and the second friction clutch is disposed around the first friction clutch so as to effectively transmit and distribute power to each wheel in compact and simple structure.

Abstract: A casing is provided in a power train of a four-wheel drive motor vehicle and supported on a body of the vehicle. A fluid operated multiple-disk friction clutch is disposed in the casing. The clutch has a drive drum operatively connected to an input member of the power train and a driven drum operatively connected to an output member of the power train, and a piston slidably mounted in a piston chamber and operated by oil supplied to the piston chamber for engaging the drive drum with the driven drum. A hydraulic circuit having an oil pump is provided for exclusively supplying oil to the piston chamber.

Abstract: A control system for actuating various types of clutches includes a first piston which contacts a clutch disc associated with a first shaft. The first piston forces the first shaft clutch disc into a corresponding clutch disc associated with a second shaft. A second piston is received within a fluid chamber, and is reciprocated by a motor to force fluid outwardly of the fluid chamber and against the first piston. In this way, the position of the second piston controls the force of the first piston against the clutch disc of the first shaft. An electronic control for the second piston motor accurately controls the position of the second piston to control the force of the first piston on the clutch discs. The first and second pistons, the ball screw motor, the fluid chambers and the fluid paths are all received in a casing for the shafts. In this way, the size of the clutch is reduced over prior art assemblies which typically required a separate pump removed from the casing.

Abstract: An electronically controlled differential limiting system comprises a differential case, a differential pinion, a pair of opposing differential side gears respectively splined to left and right axle shafts, a clutch operably provided between the differential case and the side gear, and stepped portions disposed in the differential case, for receiving an engaging force acting to increase engagement between the pinion and the side gear so as to prevent the engaging force from being transmitted to the side gear during application of the clutch, and for receiving a reaction force transmitted from the pinion to the side gears so as to prevent the reaction force from being transmitted to the clutch during rotation of the pinion.

Abstract: An internal disconnect mechanism for a planetary gear differential permits operation in either an engaged mode, wherein a driving connection is provided therethrough, and in a disengaged mode, wherein no driving connection is provided. The differential includes a case which is rotatable about an axis having first and second spur gears disposed therein, each adapted to be connected to an output shaft for rotation therewith. A first plurality of planetary gears mounted for rotation within the case mesh with the first spur gear and are axially immovable. A second plurality of planetary gears mounted for rotation within the case mesh with the second spur gear. Unlike the first planetary gears, however, the second planetary gears are axially movable between engaged and disengaged positions. In the engaged position, each of the second planetary gears meshes with a corresponding one of the first planetary gears. Thus, the differential functions in a normal manner.

Abstract: In an all-wheel driven field tractor whose front-axle differential (6) and rear-axle differential (15) are permanently driven in arable land by output shafts (2 and 3) of a gear change (1) so that a rigid connection exists between front and rear axles, the higher speeds of the front axle (7) appearing when cornering must be compensated. Besides, a mechanism for compensating the axle speeds must be adapted to be integrated in the field tractor without substantial constructural changes. For this purposse there is situated between the crown gear (12) and the differential cage (14) of the rear-axle differential (15) a clutch (16) designed as a control slip clutch having its slip status regulated according to the parameters of the track radius to be executed and/or the traction needed.

Abstract: This device, comprising a housing (10), an input member and two output members (14, 15) as well as a controlled-slip coupling device (23) arranged between two of the said input and output members, is characterized in that the differential comprises at least one member (14) axially movable under the effect of a torque exerted on it, the displacement of this member being utilized to modify the operating characteristics of the controlled-slip coupling.This provides a differential with a slip self-controlled as a function of the torque and of the speed difference between the output members, the law of variation of which is appreciably improved in relation to that of the known devices.

Abstract: A limited slip differential for a vehicle comprises a friction clutch disposed between a differential gear mechanism and a drive wheel axle, a clutch control cylinder for coupling and decoupling the friction clutch, a normally closed type solenoid valve for charging compressed air to the cylinder from a pressure air source and a normally opened type solenoid valve for discharging compressed air from the cylinder to the air. The normally closed type and normally opened type solenoid valves are operated by a control unit in response to a low .mu. road start, a low .mu. road run, a straight run and a brake so as to charge and discharge compressed air to and from the cylinder and thereby to control air pressure in the cylinder. A power device for a vehicle is composed by adding an engine control cylinder disposed in an acceleration control mechanism and an engine control valve for charging and discharging compressed air to the cylinder, and wherein during a low .mu.

Abstract: A power transmitting apparatus on a four-wheel-drive motor vehicle can distribute and transmit drive power from a power unit to front and rear drive road wheels such that the rotational speeds of the front and rear drive road wheels can differ from each other.

Abstract: A power transmitting device of a bevel gear differential provided coaxially with axles. The differential has a differential case, a pair of pinions rotatably supported in the differential case, a pair of side gears meshed with the pinions and secured to respective axles of the vehicle, and a final reduction gear secured to the differential case. A fluid-operated clutch controls the differential operation of the limited slip differential. The clutch has an outer drum integral with the differential case, an inner drum connected to one of the side gears, a plurality of outer disks secured to the outer drum, a plurality of inner disks secured to the inner drum, a piston slidably mounted in a piston chamber and operated by oil supplied to the piston chamber for engaging the outer drum with the inner drum, the outer disks and inner disks being disposed alternately with each other. Sealing members separate oil supplied to the piston chamber from oil for lubricating the final reduction gear.

Abstract: In a four wheel drive vehicle having an anti-lock brake system in combination with a front differential gear, a rear differential gear and a center differential gear, a center differential lock mechanism between the front differential gear and the center differential gear is automatically disengaged when a throttle opening sensor detects a low degree of throttle opening independently of the vehicle speed. The device for automatically disengaging the center differential lock mechanism is operated under the control of an operating unit receiving input signals from a center differential gear operating switch, a vehicle speed sensor, a rear wheel speed sensor, a brake lamp sensor and a throttle opening sensor.

Abstract: A disengageable four-wheel-drive transmission system for motor vehicles with transverse gearbox includes a gradually-engageable hydraulic clutch controlled automatically by an electronic control unit in dependence on operating parameters including the torque transmitted by the engine of the vehicle at the time in question. The electronic control unit is arranged to cause the clutch to be engaged gradually from a disengaged condition in which the drive is transmitted from the gearbox only to the front differential or the rear differential of the transmission system.

Abstract: A central differential comprising a planetary gear device is parallel to front axles of a motor vehicle, and coaxially to a transfer shaft of a transfer device. The planetary gear device comprises a first sun gear connected to an output shaft of a transmission, a carrier, first and second planetary pinions integral with each other and rotatably supported on the carrier, and a second sun gear. The first planetary pinion is engaged with the first sun gear, and the second planetary pinion is engaged with the second sun gear. A fluid operated multiple-disk clutch is disposed coaxial to the central differential so as to restrict the differential operation of the planetary gear device.

Abstract: The invention relates to a device for the prevention of slippage on one side of a wheel on a motor vehicle driving axle with differential gearing. The device contains a sensor unit for detection of the slippage of a driving wheel and an electronic processing and control unit installed downstream. By means of an actuating element, braking or locking of a rotating part of the drive system can be effected, the actuating element being capable of being triggered by means of an electric control line. There is provided in this control line a mechanically actuatable switch that can be actuated as a function of the engine transmission position and that is deactivated when higher drive speed ranges are engaged. As a result, the device for prevention of slippage on one side, especially brake application on one side, can be activated by the safety switch as a starting assistance in performing a cross-lock function only at low speeds, preferably in first gear or first transmission speed range.

Abstract: To simplify propeller shaft supporting structure and to reduce propeller shaft vibration when a viscous coupling and a clutch mechanism are both provided on a propeller shaft of a 4WD vehicle, the power transmission apparatus comprises a housing rotatably supported to receive power; a differential gear disposed on one side of and within the housing; a viscous coupling disposed on the other side of and within the housing; and a clutch for transmitting power from the housing to the differential gear via the viscous coupling when engaged, and transmitting no power from the housing to the differential gear when disengaged.

Abstract: To provide symmetrically wide inner spaces near two front or rear wheels of an automotive vehicle in which an engine and a transmission are arranged in series in the vehicle transversal direction, a first large-sized viscous coupling is disposed near a small-sized front or rear differential gear to limit the differential motion thereof; and a second small-sized viscous coupling is disposed near a large-sized center differential gear to limit the differential motion thereof. The center differential gear is disposed on the transmission side to differentially distribute engine power to front and rear wheels, and the front or rear differential gear is disposed on the engine side to further differentially distribute engine power distributed by the center differential gear to right and left wheels.

Abstract: To stably control clutch engagement torque of a multidisk friction plate clutch provided between two rotary members, without being directly subjected to the influence of friction plate wear or of fluctuations in friction coefficient between two clutch plates, the coupling apparatus comprises a pilot clutch, a main clutch and dual cam ring members disposed between the two clutches. When the pilot clutch is engaged by an actuator in a first direction, since a first slidable cam ring rotation is limited by the pilot clutch relative to a second fixed cam ring, the first slidable cam ring is shifted in a second opposite direction by a cam thrust force to engage the main clutch. The coupling apparatus is suitably incorporated in a differential gear assembly mounted on automotive vehicles in order to controllably and stably limit the differential motion between two shafts.

Abstract: A central differential comprising a planetary gear device is coaxially mounted on one of the axles of a motor vehicle. The planetary gear device comprises a first sun gear connected to an output shaft of a transmission, a carrier, first and second planetary pinions integral with each other and rotatably supported on the carrier, and a second sun gear. The first planetary pinion is engaged with the first sun gear, and the second planetary pinion is engaged with the second sun gear. A fluid-operated multiple-disk clutch is disposed so as to restrict the differential operation of the planetary gear device.

Abstract: The invention is concerned with a drive assembly (8) comprising a differential (16). The differential (16) comprises a driving carrier (18) and two driven output gears (19) connected to joints (11) to driveshafts (12). The assembly (8) also comprises a coupling (48) by which one of the gears (19) may be connected directly to the carrier (18). The joint (11) associated with said gear (19) is positioned outside the differential (16) directly adjacent thereto and extends coaxially around an outer part (26) of the joint (11). An inner part of the coupling (48) is connected to the outer part of the joint (11) and an outer part (31) of the coupling is connectable to the carrier (18). The coupling (48) may be a viscous coupling.

Abstract: An automatic power shift transfer case for a four wheel drive vehicle has a front high-low range planetary gear set and a rear differential planetary gear set aligned symmetrically about the transfer case central shaft axis. The front and rear planetary gear sets are arranged in a back-to-back substantially mirror image manner so as to share a common carrier interposed therebetween. The front planetary gear set with either its low or high range clutch applied selectively delivers a corresponding speed through the common carrier to the rear planetary gear set. The torque flow is split in a predetermined manner wherein a minimum torque to maximum may be selectively delivered to the rear axle, via a rear planetary gear set modulating clutch while the remaining torque is normally delivered to the front axle. Lock-up of the modulating clutch allows the front axle to be disconnected providing a two-wheel drive mode.

Abstract: A vehicle differential includes a clutch assembly and a hydraulic actuator for selectively preventing relative rotation between a pair of vehicle half axles. The differential assembly has an outer housing rotatably mounting a gear case and ring gear therein. A planetary gear assembly is coupled between the gear case and one half axle. The planetary gear assembly is also coupled to a sun gear which in turn is coupled to the other half axle. The clutch assembly is coupled between the gear case and the sun gear. An annular manifold is fixedly mounted in the outer housing and sealingly engages an outer surface of the gear case for supplying pressured hydraulic fluid to actuate a piston in a cylinder formed in the gear case which in turn actuates the clutch assembly. The pressure of the hydraulic fluid determines a range of torque differentials for which the clutch assembly will prevent relative rotation between the half axles.

Abstract: In order to construct a four wheel drive of a motor vehicle as a compact constructional unit with a low space requirement, the two output shafts of the rotating four wheel locking system are disposed in one another. A cylindrical lock housing encloses the locking system including a planet gear transfer transmission and a disk bundle at a narrow axial and radial distance.

Abstract: In a power transfer mechanism including an input shaft arranged to be applied with drive torque from a prime mover of a motor vehicle, a first output shaft arranged coaxially with the input shaft for drive connection to a first set of drive axles and a second output shaft arranged in parallel with the first output shaft for drive connection to a second set of drive axles, a planetary gearset of the double pinion type is mounted on the first output shaft to transfer the drive torque from the input shaft to the first and second output shafts, the planetary gearset including a ring gear in drive connection to the input shaft, a sun gear in drive connection to the first output shaft and a planet carrier for drive connection to the second output shaft, a limited-slip differential in the form of a viscous fluid coupling is disposed between the ring gear and planet carrier to limit differential action between the first and second output shafts, and a drive train for drive connection between the planet carrier and th

Abstract: For a part time four wheel drive vehicle, auxiliary drive power is handled by an interaxle transfer mechanism comprising a braked differential gear set interposed in the vehicle's auxiliary motive power path, providing, in addition to the normal two wheel drive mode and front-rear-locked four wheel drive mode, a limited-slip-auxiliary four wheel drive mode. The differential gear set may be of the planetary or bevel gear type; its reaction gear is coupled to a braking unit, preferably of the hydraulic disk-pad-caliper type which is readily accessible and highly serviceable. The transfer mechanism is typically interposed concentrically at the driven end of the vehicle's auxiliary driveshaft, and may be retrofitted onto existing vehicles of the type having a gear or chain driven offset auxiliary driveshaft by adding an extension gear casing which carries the braking unit externally.

Abstract: A differential gear mechanism is provided of the type including a gear case (17), at least one pinion gear (21), and a pair of side gears (27 and 29). Clutch packs (43 and 45) are disposed between the side gears and the gear case and are operable, when engaged, to retard relative rotation between the gear case and the side gears. The mechanism includes a fluid pressure actuated displacement mechanism (57) which, in response to an external signal (71) transmits its output displacment into axial movement of a plurality of input members (81). The axial movemenat of the input members has an actuating travel X and an actuating force F. A pair of lever members (85) receives the axial input from the input members 81, with each lever member pivoting about a fulcrum member (91) to transmit to each of the clutches a clutch actuating movement having an actuating travel substantially less than the actuating travel X, and an actuating force substantially greater than the actuating force F.

Abstract: A clutch assembly (35) is disclosed of the type which can retard rotation of an output member (27) relative to an input member (33). The clutch assembly includes discs (59, 61) fixed for rotation with the input and output members, respectively. Also included is a clutch apply piston (63) which defines a high pressure chamber (67), the apply piston being responsive to pressure in the high pressure chamber to apply a biasing force to the clutch discs. A low pressure piston (69) defines a low pressure chamber (79), the low pressure piston having a transverse area (A) and also including a secondary piston portion (71) extending axially into the high pressure chamber and having a transverse area (B) the volume of the high pressure chamber (67) is maintained substantially constant by a chamber piston (65) and a one-way clutch assembly (93).

Abstract: A method of and system for controlling a torque distribution over four wheels of four-wheel drive vehicle when the vehicle is making a turn. When an outer wheel revolution speed is higher than an inner wheel revolution speed, a differential action limiting force is decreased or weakened and a torque distribution ratio, viz., a ratio of a portion of torque distributed toward the front wheels (secondary driving wheels) to the remaining portion of torque distributed toward the rear wheels (primary driving wheels), is decreased. When the inner wheel revolution speed is higher than the outer wheel revolution speed, the differential acting limiting force is increased or strengthened and the torque distribution ratio is increased.

Abstract: An active torque distribution controller for the wheels of a motor vehicle detects a longitudinal acceleration and a side acceleration to which the vehicle is subject. Based on these longitudinal and side accelerations, a running mode which the vehicle is involved in is detected, and a torque distribution ratio of a portion of torque delivered to the front wheels to the remaining portion to the rear wheels and a differential limiting force are varied in response to a predetermined control schedule for the running mode detected.

Abstract: A power transmission apparatus comprises a device for transmitting power by frictional force between first and second rotary members rotated relative to each other; a device for pressing the power transmitting device in a direction of increasing frictional force; a drive device for driving the pressing device in the direction of increasing frictional force; and a stopper for restricting the movement of the drive device.

Abstract: A limited slip differential includes a differential carrier for supporting rotatably a differential case, surrounding the differential case and first and second frictional materials and having a piston chamber connected to an outside pressure source, a first piston disposed shiftably and unrotatably in the piston chamber, a second piston disposed rotatably together with the first frictional materials and shiftably along a rotary axis of the differential case and a thrust bearing disposed between the first and second pistons.

Abstract: An all-wheel driven motor vehicle capable of operating in an understeering or an oversteering condition comprises a front axle, a rear axle, and an interaxle differential comprising a planetary gear system, a releasable coupling, and a liquid friction coupling. The planetary gear system includes an input member connected to the motor of the vehicle, a first output member connected to the front axle, and a second output member connected to the rear axle. The releasable coupling interconnects the first and second output members. The liquid friction coupling is disposed between the first output member and the front axle. The three-torque transmitting members of the planetary gear system are selected so that when the releasable coupling is disengaged, the vehicle operates in an understeering condition under normal running conditions.

Abstract: An integrated roll rigidity and differential slip control system for a wheeled vehicle comprises roll rigidity changing means for changing roll rigidity distribution to front and rear wheel sides, roll rigidity control means for controlling the operation of said roll rigidity changing means based on vehicle running conditions, a differential interposed between the rear wheels, clutch means for supplying a slip limiting force to the differential to limit differential action thereof, and slip control means for controlling engagement of the clutch means based on vehicle running conditions and integrated control means for controlling, in preference to the control by the roll rigidity control means, the roll rigidity distribution in such a way that a roll rigidity is larger on the front wheel side and smaller on the rear wheel side in response to a cornering condition in which a driving force is distributed more to a cornering outside driving wheel than to a cornering inside driving wheel.

Abstract: A four-wheel drive vehicle has an engine output shaft; a transmission having an input shaft connected to the output shaft and an output shaft connected through a transmission mechanism to the input shaft; a drive gear meshed with an output gear connected to the output shaft of the transmission; a front wheel side power transmitting mechanism; a rear wheel side power transmitting mechanism; a center differential mechanism coaxial with the drive gear and having an input member connected to the drive gear, a first output member connected to the front wheel side power transmitting mechanism, and a second output member connected to the rear wheel side power transmitting mechanism; a front differential gear coaxial with the center differential mechanism and connected to the first output member of the center differential mechanism; a power converting gear mechanism for converting a rotation about a first axis to a rotation about a second axis being perpendicular to the first axis to transmit power to the rear side p