Abstract: To achieve automatic setting into coincidence, the following are provided: a mechanical tension elements arranged to act on an upstream member (9) substantially along the axis (X) along which approach elements (13) act, but in the opposite direction; elements (37) for constraining the member (9) in rotation with a mechanical angular guide element; and phase-shifter elements (47) for shifting the phase of the upstream member (9) relative to the downstream member (10) by sliding against a reference that is stationary in rotation relative to the downstream member (10).

Abstract: A pump system that pressurizes a fluid includes a shaft, a first rotor and a second rotor that is selectively driven by the shaft. Relative rotation between the first rotor and the second rotor generates variable sized pockets therebetween to pressurize the fluid. A clutch regulates a degree of coupling of the rotor to the shaft between a decoupled state and a coupled state to regulate the relative rotation between the first and second rotors.

Abstract: An apparatus for adjusting the power transfer capabilities of two, shifting elements, by way of which output torque of a transmission of a vehicle can be conducted in a direction transverse to the longitudinal axis of the vehicle to driving wheels of a drivable vehicle axle with the inherent degrees of apportionment as conducted in relationship to the power transfer capability of the shifting elements. Each shifting element has an electric motor; a transmission operationally connected with the electric motor; and placed between the shifting element and the transmission apparatus, a drive converter apparatus, by way of which rotationally directed drive of the electric motors is respectively transformed into a translational activation motion for the control of the shifting elements. The drive converter apparatuses respectively possess a first drive element and a second drive element of which one drive element, converse to the other drive element, is of translational movement.

Abstract: A torque transfer mechanism is provided for controlling the magnitude of a clutch engagement force exerted on a multi-plate clutch assembly that is operably disposed between a first rotary and a second rotary member. The torque transfer mechanism includes a power-operated face gear clutch actuator for generating and applying a clutch engagement force on the clutch assembly.

Abstract: A torque transfer mechanism is provided for controlling the magnitude of a clutch engagement force exerted on a multi-plate clutch assembly that is operably disposed between a first rotary and a second rotary member. The torque transfer mechanism includes a power-operated face gear clutch actuator for generating and applying a clutch engagement force on the clutch assembly.

Abstract: The present invention provides a shift mechanism disposed in a housing for providing operable communication between a shift actuator and a shift sleeve. The shift mechanism generally includes a shift rail, a shift fork, a first biasing member, and a second biasing member. The shift rail is slidably supported by the housing. The shift fork is slidably disposed on the shift rail and engages the shift sleeve. The first biasing member is disposed between the shift actuator and the shift rail for selectively biasing the shift rail in a first direction upon actuation of the shift actuator. The second biasing member is disposed between the housing and the shift fork for biasing the shift fork in a second direction that is substantially opposite the first direction.

Abstract: The torque transmission apparatus is simple, small and light and has a clutch unit to receive thrust and transmit torque between rotary members, a differential screw mechanism to convert rotational force into the thrust applied to the clutch unit, and an electric motor to produce the rotational force. The differential screw mechanism has a driving screw and driven screws. The driving screw is rotatably and axially movably supported on a rotary drive shaft of the electric motor. The driven screws mesh with the driving screw and are rotatably and axially immovably supported. The meshing driving screw and driven screws are rotated to axially move the driving screw and apply engaging force to the clutch unit.

Abstract: A transfer case for selectively coupling a secondary driveline with a primary driveline comprises: a first output shaft; a second output shaft; a clutch assembly disposed at the second output shaft, the clutch assembly including inner and outer drum members, one of the inner and outer drum members rotatable in association with rotation of the first output shaft and the other one of the inner and outer drum members coupled with the second output shaft, the clutch assembly further including a plurality of frictional clutch plates, the frictional clutch plates formed of at least one frictional clutch plate coupled with the inner drum member and at least one frictional clutch plate coupled with the outer drum member; an actuator shaft rotatably coupled with an actuator; and a clutch actuator means coupled with the actuator for applying axial force to the frictional clutch plates to transmit a drive torque of the first output shaft to the second output shaft.

Abstract: Electric-motor drive control means controls a clutch engaging/disengaging actuator including two electric motors. When a vehicle starts moving or changes gears, the electric-motor drive control means drives both of the two electric motors in drive modes that require high responsiveness from an automatic clutch device and drives the two electric motors alternately in other drive modes that do not require high responsiveness. Malfunctions of the electric motors are detected during the operation. When one of the electric motors malfunctions, a warning is issued and the actuator is driven with the other electric motor that is normal. When both of the electric motors malfunction, a warning prompting a driver to stop the vehicle is issued.

Abstract: An electrically actuated torque transfer device for use in a motor vehicle including an input shaft coupled to one or more output shafts. A modulating clutch assembly selectively couples the input shaft to the output shaft and includes an electrical clutch operator. The clutch assembly transfers torque from the input shaft to the at least one output shaft in proportion to an electrical current applied to the electrical clutch operator. A machine readable calibration tag is attached to the torque transfer device to store a unique torque profile for each torque transfer device. The torque profile includes a range of measured torque values transferred from the input shaft to the output shaft for each of a range of applied electrical currents.

Abstract: The present invention provides an electromagnetic clutch that can restrict output torque to a predetermined range against the variation of the voltage of the power supply and the environmental temperature. The electromagnetic clutch comprises: an armature; a rotor that attracts the armature; a plurality of slits that are formed in the armature and the rotor around circumferential directions thereof; and a plurality of annular attraction surfaces that are formed on the armature and the rotor which face each other. At least one of the circumferential sections cut in the circumferential direction at the position in the armature and the rotor where respectively face an inner slit wall of the other party, and at least one of the attraction surfaces are substantially equal to each other in area.

Abstract: The present invention is a clutch assembly which incorporates brushless motor technology to engage a clutch pack to cause two shafts to rotate in unison. The present invention is a clutch actuation assembly having a clutch apply member, a base plate disposed about an axis, a cam plate disposed about the axis, and at least one cam, operably associated with the base plate and the cam plate. The present invention also includes at least one load transferring member operably associated with the at least one cam, as well as an actuator for providing relative rotation between the cam plate and the base plate about the axis, causing the at least one load transferring member to move with respect to the at least one cam, and the cam plate to translate along the axis actuating said clutch apply member.

Abstract: The transfer case reduction gearset is often never used for its original intended function, that is, to provide an additional speed reduction (torque amplification) ratio for the powertrain. This concept allows for the increased use of the transfer case gearset components to work in concert with the automatic transmission to increase its ratio spread. This increase in ratio spread will result in improved launch performance for the vehicle by steepening the effective first gear ratio of the automatic transmission. The increase in ratio spread may also provide for reductions in numerical axle ratio of the vehicle thereby improving the fuel economy during normal highway operation. The present invention focuses on a method of shifting the transmission of the vehicle in accordance with the invention which includes providing a transmission connected to a vehicle engine having a predetermined number of gear ratios which are selectable.

Abstract: A limited slip differential comprises a housing having an input, a first output, and a second output rotatably mounted in the housing. A friction clutch in the housing limits slip between the first output and the second output, and a mechanism in the housing applies an axial force to the friction clutch. The mechanism includes a rotatable actuating plate and a non-rotatable, back-up plate. A motor that rotates the actuating plate is controlled by an electronic motor control which has a feed back that is responsive to the force applied by the mechanism to the friction clutch. In one embodiment, the feed back measures the angular position of the rotatable actuating plate which is mounted on an angular contact bearing. The stain or slight axial movement of the outer race of the angular contact bearing is measured to provide the feed back to the electronic motor control.

Abstract: A clutch device is configured to include a clutch mechanism, a clutch actuator operatively engaging and disengaging the clutch mechanism, a clutch lever, and an assist pressure generator which generates assist hydraulic pressure by driving an electric motor. The assist hydraulic pressure is supplied to the clutch actuator to operatively engage and disengage the clutch mechanism. The clutch device further includes a first turning angle sensor which detects the turn operation angle of the clutch lever, a control unit which controllably drives the electric motor based on the turning operation amount of the clutch lever and adjusts the driving force generating gain characteristic of the electric motor, and a gain adjustment knob which variably sets the gain characteristic. The clutch device makes it possible to changeably set the magnitude of an assist force of an assist device according to a rider's preference.

Abstract: A transmission control system for maintaining good positioning performance even if a dynamic characteristic of a transmission is out of a predicted range. A sliding mode controller provided in a shift controller has two degrees of freedom and can independently specify a follow-up characteristic of an actual shift arm position to follow a target position in a shifting direction and a disturbance suppressing characteristic respectively. The sliding mode controller determines a control input to be supplied to a shift motor of a shifting device. A sliding mode controller provided in a selection controller has two degrees of freedom and can independently specify a follow-up characteristic of an actual shift arm position to follow a target position in a selecting direction and a disturbance suppressing characteristic, respectively. This sliding mode controller determines a control input to be supplied to a selection motor of a selecting device.

Abstract: A clutch assembly in which a clutch, in order to engage, is pressed together against the force of the lining springiness via a lever plate. An additional spring force, which acts upon the lever plate in an opposite direction, alters the load placed on the clutch actuator whereby enabling it to be adapted to a linear compensating spring in an advantageous manner. The additional spring force is preferably applied by a disc spring, whereby the lever plate itself can be provided in the form of a lever disc spring. On the clutch actuator, a change in the direction of force can be prevented when the spring forces are appropriately matched.

Abstract: An actuating device (18) or a clutch (16) of a motor vehicle (2) comprising one electric motor (34), one gearing (36, 40, 42, 44) which converts rotational motion of the electric motor (34) into a translatory motion and one accumulator (52). The converter gearing comprises one recirculating ball spindle (44). The accumulator (52) is at least partly situated within the recirculating ball spindle (44), and at least parts (58, 60) of a displacement sensor (56) are situated within the recirculating ball spindle (44).

Abstract: A four-wheel drive center disconnect electric actuator is provided. The actuator includes a one-way motor that actuates a cam mechanism for causing engagement and disengagement of the center disconnect. The actuator achieves improved reliability and efficiency through a less expensive construction than conventional actuators.

Abstract: A clutch actuator comprises a worm shaft that rotates along with a clutch motor. The worm shaft is meshed with a worm wheel. The worm wheel is fixed to one end of a crank shaft member of a crank shaft separately from a crank arm of the crank shaft. A bearing that supports the crank shaft is provided between the worm wheel and the crank arm.

Abstract: A clutch actuator comprises a motor having a motor shaft. A worm shaft is formed with a threaded section. A worm wheel meshes with the threaded section of the worm shaft. An output rod reciprocates in an axial direction to disengage and engage a clutch. A crank shaft converts rotational motion of the worm wheel to reciprocating motion of the output rod. The motor shaft and the worm shaft are coupled by a spline connection.

Abstract: A clutch actuator comprises a clutch motor comprising motor shaft. The clutch actuator also comprises a worm shaft that is spline connected to the motor shaft. The rotary motion of the worm shaft 103 is transferred to a worm wheel 105, which is engaged with the worm shaft 103. The worm shaft 103 has a threaded portion 103c. The threaded portion 103c comprises multiple threads.

Abstract: In a clutch which is impelled by an actuator into the closed position and which automatically moves into the open position by an opening spring, the movement of the clutch into the open position is monitored and any malfunction is displayed.

Abstract: Process for reducing clutch-grabbing oscillations in a motor vehicle drive train having a drive motor, clutch and another drive train, in which process the moment transmitted by the clutch for the control of an actuator that operates an operating member of the clutch when oscillations occur is changed such that oscillations are diminished, where an electric voltage driving the actuator is modulated according to the formula: UM=UMSt*w+UMR*(1?w), whereby, w is a weighting factor which assumes a value between 0 and 1, UMst is a modulation voltage controlled in a defined manner by an actuator model and a required travel modulation and, UMR is a modulation voltage regulated by a control device, which voltage is a magnitude that characterizes an operating state of the clutch on the basis of deviation between a required value and the actual value.

Abstract: A clutch failure detector is provided for detecting failure of an automatic clutch system. The clutch failure detector can include a current value detector and a determination device. Upon turning ON a main switch, an operation to disengage and engage a clutch can be performed by a clutch actuator, and a totalized value of current supplied to a clutch actuator can be calculated for a specific period of time while the clutch is in the process of engaging in the operation to disengage and engage the clutch. The totalized value can be compared with a preset threshold, and if a difference between the totalized value and the threshold is equal to or greater than a given value, it is determined that an automatic clutch system has a failure.

Abstract: A motor applies torque to a ball and ramp actuator element generating thrust that is transferred thru a bearing from the stationary actuator to the rotating clutch pack elements of a marine transmission.

Abstract: A torque transfer mechanism is provided for controlling the magnitude of a clutch engagement force exerted on a multi-plate clutch assembly that is operably disposed between a first rotary and a second rotary member. The torque transfer mechanism includes a power-operated face gear clutch actuator for generating and applying a clutch engagement force on the clutch assembly.

Abstract: A transfer case (12) for distributing a driving torque of an input shaft (19) between two drivable output shafts (22, 29) is described. The transfer case (12) is realized with two controllable and adjustable frictionally engaged clutches (k_VA, k_HA), which are arranged between the input shaft (19) and the output shafts (22, 29) and whose transfer capabilities can be respectively adjusted via separate actuating devices (10, 11). A driving torque can be distributed between the drivable output torques (22, 29) in dependence upon the set transfer capabilities of the clutches (k_VA, k_HA). One clutch (k_HA) can also be radially enclosed by the other clutch (k_VA).

Abstract: A gear shifting system for idler wheels (3) comprising sliding sleeves (2), which are connected torsion-resistant with a main shaft (1) and can be connected form-locking with an idler wheel (3) to be shifted via axial displacement. Actuation of the respective sliding sleeve (2) is provided through at least one adjusting unit (4), which selects an actuator such that a shifting actuation of the respective sliding sleeve (2) is possible.

Abstract: In order to form a torque transmission coupling to be compact, the present invention provides a torque transmission coupling (1) comprising input-output rotary members (57, 59) rotatably supported to perform input-output transmission of torque; a frictional engagement section (79) provided between the input-output rotary members to perform torque transmission between the input-output rotary members by enforcing frictional engagement; a compression member set (87) that comprises a pair of members (89, 91)capable of performing relative rotation and that generates thrust through the relative rotation between the members to thereby cause the frictional engagement section to perform the frictional engagement; and a rotary actuator (121) that causes both of the members of the compression member set to perform engagement-rotational driving whereby to cause the relative rotation.

Abstract: A torque transfer mechanism is provided for controlling the magnitude of a clutch engagement force exerted on a multi-plate clutch assembly that is operably disposed between a first rotary and a second rotary member. The torque transfer mechanism includes a clutch actuator for generating and applying a clutch engagement force on the clutch assembly.

Abstract: A power transmission device includes a rotary input member adapted to receive drive torque from a source of torque, a rotary output member adapted to provide drive torque to an output device and a torque transfer mechanism operable to transferring drive torque from the input member to the output member. The torque transfer mechanism includes a friction clutch assembly operably disposed between the input member and the output member and a hydraulic clutch actuation system operable for applying a clutch engagement force to the friction clutch assembly. The hydraulic clutch actuation system includes an electric motor drivingly coupled to a first piston. The first piston is slidably positioned within the housing for supplying pressurized fluid to an accumulator. The pressurized fluid within the accumulator is in communication with a second piston to provide the clutch engagement force.

Abstract: A motion transmitting apparatus wherein an electric motor, an engine or another prime mover rotates an axially fixed first part relative to a coaxial axially movable non-rotatable second part. The structure which serves to move the second part axially in response to clockwise or counterclockwise rotation of the first part includes a follower borne by the first part and a helical spring having end convolutions affixed to the first part. The follower extends between two intermediate convolutions of the helical spring. If the apparatus is utilized in the power train of a motor vehicle, the axially movable part can serve to engage or disengage or change the extent of engagement of the friction clutch between the output element of the engine and the input element of the change-speed transmission.

Abstract: In a clutch unit, an engagement of a dog clutch can be restricted until a revolution of an input shaft and the revolution of an output shaft correspond to each other so as to be suitable for the engagement. The engagement can be effected when the revolution of the input shaft and the revolution of the output shaft have corresponded so as to be suitable for the engagement. Accordingly, the revolution of the input shaft and the revolution of the output shaft are speedily synchronized, and engagement shocks of the dog clutch can be accurately suppressed. Hence, it is possible to reliably transmit the torque to be transmitted from the driving source to the wheel side through the reduction mechanism.

Abstract: A torque transfer mechanism is provided for controlling the magnitude of a clutch engagement force exerted on a multi-plate clutch assembly that is operably disposed between a first rotary and a second rotary member. The torque transfer mechanism includes a power-operated face gear clutch actuator for generating and applying a clutch engagement force on the clutch assembly.

Abstract: The present invention provides a shift mechanism disposed in a housing for providing operable communication between a shift actuator and a shift sleeve. The shift mechanism generally includes a shift rail, a shift fork, a first biasing member, and a second biasing member. The shift rail is slidably supported by the housing. The shift fork is slidably disposed on the shift rail and engages the shift sleeve. The first biasing member is disposed between the shift actuator and the shift rail for selectively biasing the shift rail in a first direction upon actuation of the shift actuator. The second biasing member is disposed between the housing and the shift fork for biasing the shift fork in a second direction that is substantially opposite the first direction.

Abstract: A torque-transmitting mechanism has an electric motor apply apparatus. The electric motor is operable to control a drag torque on a rotatable plate for a torque-to-thrust apparatus. The control of the rotatable plate by the electric motor and drag torque results in a thrust force being applied to the torque-transmitting mechanism such that the torque-transmitting mechanism is conditioned to transmit torque between two members of a power transmission.

Abstract: A torque transmission apparatus includes a clutch housing and a clutch hub, a frictional multi-plate clutch for transmitting torque between the clutch housing and the clutch hub, a pressurizing member for bringing the frictional multi-plate clutch into engagement by producing a thrust, and a motor for generating a relative rotation between members by rotation of member of the pressurizing member. In the torque transmission apparatus, an accommodating recessed portion is provided in an outer wall of the clutch housing, wherein the pressurizing member disposed in the accommodating recessed portion, a penetrating portion which confronts the pressurizing member is provided in the outer wall, and a transmission member interposed between the pressurizing member and a flange portion of the clutch hub for transferring a thrust of the pressurizing member to the clutch hub is disposed in the penetrating portion so as to pass therethrough.

Abstract: A transfer case (1) with controllable clutch (5) for a motor vehicle, especially for a motor vehicle with part-time four-wheel drive, for distributing a driving torque coming in via a drive shaft (2) to at least two output shafts (3, 4). Hereby the output shaft (4) can be connected to the drive shaft (2) via the clutch (5), and the clutch (5) can be actuated via an electric motor (9) and a drive converter device (10) that is arranged between the electric motor (9) and the clutch (5) for converting a rotatory motion of the electric motor (9) into a translatory actuating motion for the clutch (5). The electric motor (9) is hereby designed as an induction motor.

Abstract: A device for setting the torque transmitted by a friction clutch (12), having an actuator chain which comprises an electric motor (45), a step-down gear (42) and a mechanism for converting the rotational movement into a displacement of a pressure plate (29) of the clutch (12), so as to enable the torque which is transmitted to be set precisely and rapidly even given high friction. For this purpose, the electric motor (45) and/or step-down gear (42) is/are affected by friction, the conversion mechanism (31, 32, 35, 36, 40) and/or the friction clutch (12) itself is/are affected by elasticity, and, to set the torque (Md) of the friction clutch (12), a position regulator (47) which is operatively connected to the electric motor (45) and a sensor (46; 46?) which determines the position of one of the links of the actuator chain (45, 42, 41, 40, 36, 35, 32, 31, 29) are provided, the sensor being present at a location upstream of a substantial part of the elasticity in the force-flow direction.

Abstract: A distributor gear (1) with an adjustable coupling device (5) for a vehicle, in particular for a vehicle with a shiftable all-wheel drive is described for the distribution of an incoming drive torque via a drive shaft (2) to at least two output shafts (3, 4). It is moreover provided that an output shaft (4) can be connected via the coupling device (5) with the drive shaft (2) and that the coupling device (5) can be actuated via an electric motor (9) and a drive converter device (10) located between the electric motor (9) and the coupling device (5) for the conversion of rotary movement of the electric motor (9) into a translatory actuation movement for the coupling device (5). The electric motor (9) is incorporated into a gear (7).

Abstract: A torque-to-thrust apparatus includes a one-way mechanism permitting free application of rotation to torque. A friction plate disposed between a portion of a one-way device and a stationary member of the torque-to-thrust apparatus inhibits reverse rotation at a predetermined torque level, which will maintain the thrust member of the torque-to-thrust apparatus in an engaged condition until a predetermined load is applied to the rotary side of the torque-to-thrust apparatus to overcome the friction load.

Abstract: An automatic powershift gearbox with at least one gearbox assembly for selecting the respective gear ratios and with at least one multiple-disk clutch capable of being actuated in a controlled manner for holding or releasing individual elements of the planet gear, which allows gear shift operations without interrupting the torque flow. The multiple-disk clutch comprises a first and a second disk set which are in mutual engagement and can be brought into friction engagement by axial compression against one another. The first disk set is connected with a first shaft, and the second disk set is connected with a second shaft. The multiple-disk clutch is coupled by a transmission with an electric machine comprising a rotor and a stator, for bringing the two disk sets into and out of friction engagement by means of the electric machine. The rotor of the electric machine is supported rotatably and axially movable on one of the shafts by means of a gearbox for converting a rotary motion into a thrust motion.

Abstract: A variable speed slip clutch is provided. The clutch has an output shaft, a first and second input hub, and output hub, a wrap spring and a control hub. In one embodiment, the clutch includes a source coupler coupled to a first and a second input drive. The output shaft is configured to rotate. The first input hub is coupled to the first input drive and configured to rotate about the output shaft in a first direction. The second input hub is coupled to the second input drive and configured to rotate about the output shaft in a second direction opposite the first direction. The output hub fixed to the output shaft and configured to rotate therewith. The wrap spring has a first and a second end. The first end of the wrap spring is fixed to the output hub such that the first end of the wrap spring rotates with rotation of the output hub. The control hub is coupled to the second end of the wrap spring. In one embodiment a control motor is provided and coupled to the control hub.

Abstract: An electromagnetic clutch especially adapted for use in motor vehicle power trains includes a multiple plate friction clutch pack acted upon (compressed) by a ball ramp operator. The ball ramp operator includes two adjacent plates having opposed pairs of arcuate ramped recesses which receive a load transferring member such as a ball or roller bearing. Relative rotation of the plates is achieved through a worm gear drive from a bi-directional electric motor. Such relative rotation causes separation of the plates and compression of the friction clutch pack which transfers torque from the input to the output of the electromagnetic clutch.

Abstract: A torque transfer mechanism is provided for controlling the magnitude of a clutch engagement force exerted on a multi-plate clutch assembly that is operably disposed between a first rotary and a second rotary member. The torque transfer mechanism includes a clutch actuator for generating and applying a clutch engagement force on the clutch assembly.

Abstract: An actuator for engagement and disengagement operation of a power transmission device is provided with a first plate being fixed, a second plate being movable in a direction of the engagement and disengagement operation so as to be engaged with the first plate, a third plate disposed opposite to the second plate with respect to the first plate, the third plate being rotatably engaged with the second plate, a drive unit engageable with the third plate so as to rotate the third plate, a cam mechanism converting a rotation of the third plate to a movement of the second plate in the direction of the engagement and disengagement operation and a retaining device restricting a relative rotation range of the third plate with respect to the drive unit. The second plate moved by the cam mechanism drives the power transmission device in the direction of the engagement and disengagement operation so as to intermit a power transmission thereof.

Abstract: A transmission actuator has a torque generating mechanism for generating a torque from a drive shaft, a speed reduction mechanism for multiplying a torque from the torque generating mechanism through a differential motion produced by a difference in gear ratio between a gearset of a first internally toothed gear and a first externally toothed gear and a gearset of a second internally toothed gear and a second externally toothed gear, a motion direction changing mechanism for converting the torque multiplied into a thrust and a friction engagement mechanism for transmitting power from an input shaft to an output shaft by virtue of the thrust so converted, wherein the drive shaft is made hollow so that the input shaft and the output shaft are disposed in a hollow portion of the drive shaft.

Abstract: A torque transfer mechanism is provided for controlling the magnitude of a clutch engagement force exerted on a multi-plate clutch assembly that is operably disposed between a first rotary and a second rotary member. The torque transfer mechanism includes a clutch actuator assembly for generating and applying a clutch engagement force on the clutch assembly. The clutch actuator assembly includes an electric motor/brake unit, a torque/force conversion mechanism, and a force amplification mechanism. The motor/brake unit can be operated in either of a motor mode or a brake mode to cause bi-directional linear movement of an output member of the torque/force conversion mechanism. The thrust force generated by the torque/force conversion mechanism is increased by the force amplification mechanism with the resultant clutch engagement force applied to the clutch assembly. The dual mode feature of the electric motor/brake unit significantly reduces the power requirements.

Abstract: A vehicle drive system includes a compact drive mode-shifting mechanism that is mounted in the final drive gearset of a vehicle. The drive mode-shifting mechanism includes a first shaft, a second shaft, and a clutch assembly. The first shaft forms an input shaft for the differential for a pair of wheels, the second shaft transmits engine power and the clutch assembly connects and disconnects the first and second shafts to one another to effect either the two-wheel-drive mode or the four-wheel-drive mode. The first shaft has an outer surface provided with a first spline, the second shaft has an outer surface provided with a second spline, and said clutch assembly includes an axially movable shifting member provided with an internal spline.