Abstract: The hydraulic coupling according to the present invention generally includes a multi-plate clutch assembly operatively connecting a pair of rotary members, an actuator assembly for actuating the clutch assembly, and a fluid control system operable for controlling actuation of the actuator assembly. The actuator assembly includes a hydraulic pump and a piston mounted in a piston chamber for movement relative to the multi-plate clutch assembly. The fluid control system regulates the fluid pressure supplied to the piston chamber by the hydraulic pump to control the clutch engagement force exerted by the piston on the clutch assembly. The fluid control system includes an electrically-controlled flow control valve operable for regulating the fluid pressure delivered to the piston chamber. Preferably, the flow control valve is a pulse-width modulated (PWM) valve having a moveable valve element.

Abstract: An electromagnetic clutch assembly for transfer cases and other motor vehicle powertrain applications includes a friction disc clutch pack and an electromagnetic operator that applies compressive force to the clutch pack. The electromagnetic operator includes an electromagnetic coil, a rotor partially surrounding the coil, an armature and a ball ramp operator assembly that provides compressive force when the coil is energized. The rotor and armature include aligned paths or tracks of arcuate slots separated by webs or spokes which create a sinuous magnetic flux path and improve performance. The number of slots and thus the number of spokes in the rotor and armature paths are unequal. This inequality greatly reduces pulsations caused by small fluctuations in clutch engagement associated with the repeated, simultaneous alignment and non-alignment of the spokes in a rotor and armature having equal numbers of spokes. This results in improved smoothness of operation and reduces noise and vibration.

Abstract: An axial setting device especially for loading the friction plates of a friction coupling or for fixing the viscous plates of a viscous coupling having two coupling parts which are co-axially supported on a fixed housing and which are rotatable relative to one another. A pump assembly has housing parts that are connected to the one of the coupling parts and whose conveying elements are connected to the other one of the coupling parts in such a way that, when the parts rotate relative to one another, fluid is conveyed in the pump assembly. A reservoir provided for fluid with a variable volume and a pressure chamber is delimited by an axial piston. A fluid connection is made from the reservoir to the pressure chamber via the pump assembly and a pressure line and a fluid connection is made from the pressure chamber to the reservoir via a bypass line with a solenoid valve.

Abstract: A coupling for transmitting torque between two parts which are rotatable relative to one another, which coupling comprises a friction coupling whose friction plates are each non-rotatably connected to the one and to the other of the parts which are rotatable relative to one another, having a pressure chamber which is filled with a highly viscous fluid and which is formed by a housing formed in one of the rotatable parts and by a displaceable piston sealed relative to said housing, and having a pump unit in which there rotates a conveying member connected to the other one of the rotatable parts, wherein a reservoir for a highly viscous fluid is provided in the housing, which reservoir is connected to the pump unit, wherein the pressure chamber is supplied by the pump unit and the piston loads the friction coupling and wherein the pump unit is provided in the form of an internally toothed rotor pump and the conveying member forms an externally toothed rotor which is concentrically connected to the other one of

Abstract: A coupling assembly comprising a friction coupling a pressure-generating device comprising a pump body member, an axially-displaceable piston loading the friction coupling, and a pressure chamber formed by the pump body and by the piston and filled with a highly-viscous fluid, and with at least one conveying plate being provided in the pressure chamber; and a shear channel with a control member in the pressure chamber, the control member cooperating with at least one conveying plate. In a first embodiment, the shear channel with a control member forms two circumferential grooves of limited length and each covered by one of the two radial surfaces of the conveying plate, thereby forming two shear channels. Passages through the conveying plate connect the two shear channels. In a second embodiment, the shear channel with a control member forms a circumferential groove of limited length which is covered by one of the two radial surfaces of the conveying plate to form a first shear channel.

Abstract: A four-wheel drive vehicle having a first hydraulic pump operated in operative association with the rotation of front wheels, and a second hydraulic pump operated in operative association with the rotation of rear wheels, such that a difference in rotational speed is produced between the front and rear wheels, a multi-plate clutch is brought into its engaged state by a hydraulic pressure generated by the hydraulic pumps, whereby the mode of the vehicle is shifted into a four-wheel drive mode. A torque cam mechanism is disposed between a clutch piston and clutch plates, so that when the difference in rotational speed is produced between the front and rear wheels, the torque cam mechanism produces an axial thrust force immediately to promptly bring the multi-plate clutch into its engaged state. The engagement of the multi-plate clutch is achieved with a sufficient engagement force by the hydraulic pressure thereafter produced by the hydraulic pump.

Abstract: A viscous coupling having two rotatable parts in the form of a hub and a housing for the transmission of torque between the rotatable parts caused by a positive speed differential between the rotatable parts, which are supported inside one another, which are rotatable relative to one another around a common longitudinal axis, and which form an annular chamber which is filled with a highly viscous fluid and in which first coupling plates non-rotatably connected to the first one of the two rotatable parts, e.g. the hub, and second coupling plates non-rotatably connected to the second one of the rotatable parts, e.g. the housing, are arranged alternately in the longitudinal direction.

Abstract: A hydraulic clutch which is dependent on rotation speed difference comprises a rotating housing (1), a hydrostatic displacement machine (2) arranged in this housing (1), a shaft (4), a friction clutch (3) for connecting the shaft (4) to the housing (1), and a piston (26). In order to limit the torque in a very simple manner without any disturbing centrifugal force influences, and in order to cool the friction clutch, the compression chamber (24) is connected via a constriction point (27) to the interior (28) of the friction clutch (3), and the constriction point is designed as a pressure-limiting valve. This is formed by a plate spring (30) in the wall (29) of the piston (26).

Abstract: In a transmission inertia brake a ball ramp mechanism is used to load a clutch pack to slow a rotating transmission shaft where the clutch pack is carried on a one piece drive assembly having a gear section for meshing with a transmission gear, an extension section for engaging a thrust plate in an isolator assembly, a clutch section for engaging plurality of driven clutch plates in the clutch pack and a bearing section for rotational support within a brake housing. An armature having an angled peripheral surface engages a mating friction surface formed in an end plate to form a core clutch, the armature being magnetically pulled upon energization of an electrical coil. The armature is nonrotatably connected to the control ring of the ball ramp mechanism through at least one connecting pin. Belleville washers are used to apply an axial load on the ball ramp mechanism. A gerotor oil pump provides a cooling lubricant through the clutch pack in the ball ramp mechanism.

Abstract: A wrap spring clutch (10) including an input side rotating member (12), an output side rotating member (14), a pole piece (16) containing a cylindrical center bore (18), a coil spring (20) having a first end (22), a second end (24), an outer diameter (24A) and an inner diameter (24B), an end frame (26) and a switch element (28). The cylindrical center bore (18) maintains the outer diameter (24A) of the coil spring (20) thereby minimizing variations in the performance of the wrap spring clutch (10) and reducing the cost and difficulties associated with the manufacture and assembly of known designs.

Abstract: A device for transmitting torque between two rotatable, coaxial shaft members (1, 2) contains a number of alternate clutch discs (5, 6) for counteracting differential rotational speed between the two shaft members. Planetary gear means (11, 15, 16-20) are connected to the first shaft means (1). A pressure plate (7) is connected to the second shaft member (2) and is axially displaceable against the clutch discs (5, 6) for their engagement. Transmission means in the form of rollers (10) are arranged between the gear means and the pressure plate for axially displacing the pressure plate against the clutch discs at a certain rotation differential between the gear means and the pressure plate. Electrical braking means (21-24) connected to the gear means can provide a force to the transmission means for its axial displacement.

Abstract: This invention pertains to a power transmission device suited for use in a hybrid car for selective transmission of its engine and motor powers. The power transmission device is used to transmit and cut off driving forces from an internal combustion engine or a motor of a hybrid car, and includes a two-way clutch having engaging elements, and a control mechanism for controlling the locking and freeing of the two-way clutch. The control mechanism includes an electromagnetic clutch having an electromagnet and an armature. By mounting such power transmission devices on the outputs of the engine and the motor, it is possible to easily transmit and cut off driving force by simply turning on and off the electromagnet.

Abstract: In a power transmission system for a four-wheel drive vehicle, a multiple disk clutch for distributing a proportion of the torque of the front wheels to the rear wheels is provided between a driving shaft which is connected to the front wheels which are main driven wheels and a driven shaft which is connected to the rear wheels which are auxiliary driven wheels. Between the driving shaft and the driven shaft a torque cam mechanism, a hydraulic pump and a bidirectional clutch mechanism are provided, in that order. When the rotational rate of the front wheels exceeds the rotational rate of the rear wheels, the bidirectional clutch mechanism is engaged, a first rotor of the hydraulic pump which is operatively connected to the front wheels and a second rotor which is operatively connected to the rear wheels rotate relative to each other, and a rotational load is generated by a hydraulic circuit.

Abstract: A center differential (17) including a clutch pack (33), a cam ramp actuator (31) for moving the friction discs (65,67) toward an engaged position, and a viscous coupling (29) which will have a “slip speed” representative of the speed difference between the front (11) and rear (23) wheels. There is a one-way clutch (57) disposed between the output (49) of the viscous coupling (29) and the first ramp plate (51) to transmit positive torque when the vehicle is in a forward gear, but negative torque is not transmitted, for example, during braking. An override mechanism (55) is provided, including a plurality of spring biased pins (107), such that, below a predetermined speed of rotation, positive torque can also be transmitted when the vehicle is in reverse gear. The pins (107) are associated with flyweight members (97) so that, above the predetermined speed, the pins are disengaged, and positive torque can be transmitted only in forward gear.

Abstract: A driving torque transmission control apparatus that is rotatably supported onto a vehicle body through a support bearing supported by a bearing holding device including an absorber and a bearing holding member, and that is serially disposed between driving force transmission axles. The apparatus further includes a first rotating member and a second rotating member rotatably connected around a common axis relatively with each other, to electro-magnetically control a driving torque transmitted from one of driving force transmission axles to the other thereof. A frictional engage section is provided between the first and second rotating members, to transmit from one of the first and second rotating members to the other thereof. Between the first and second rotating members, there is provided an annular electro-magnet to control a transmission torque of the frictional engage section.

Abstract: A power transmission unit having an input section and an output section and a hydraulic clutch which depends on the rotational speed difference, in which unit a hydrostatic displacement machine (20) generates a pressure on the occurrence of a rotational speed difference between the input section (1; 6) and the output section (6; 1), which pressure causes a reduction in the rotational speed difference. The displacement machine consists of parts (21, 22) respectively drive-connected to the input section and the output section and one of the sections (1; 6) forms a housing (4) containing the displacement machine, the displacement machine drawing in working fluid from a suction space.

Abstract: A connection wire is connected to a part of a rear door popped up in a door-opening direction by an urging force. A pulley rotates responsive to a driving motor inside a wire-winding device to wind the connection wire thereon. In this manner, the rear door is automatically closed. The pulley is urged in a connection wire-winding direction by a power spring. A clutch is between the pulley and the driving motor. When the rear door is pressed by an operator's hands in a door-closing direction while the rear door is being closed, the pulley is rotated by the power spring, thus winding the connection wire thereon and preventing the connection wire from becoming loose. At this time, the connection between the pulley and the driving motor is cut off by the clutch. Thus, the pulley is rotated by the power spring freely and rapidly. In this manner, the rear door can be closed manually even while it is being closed automatically.

Abstract: A differential device (11) of the type including a clutch pack (23), engaged by a ball ramp actuator (21), which is initiated by a viscous coupling (19;101). The output of the device (11) is an output shaft (13) which is hollow and extends through the entire axial extent of the device. The viscous coupling (19;101) includes, in the embodiment of FIG. 1, an annular input coupling member (25) and an annular output coupling member (27), within the input member, to define therebetween a cylindrical viscous shear chamber (29). The output coupling member (27) at least partially surrounds the first ramp plate (41) of the ball ramp actuator (21), and is in driving engagement therewith, for improved packaging.

Abstract: A coupling device with two parts which are coaxially rotatable relative to one another, comprising a friction coupling whose friction plates are alternately connected to each of the rotatable parts. Further the coupling device comprises an actuating device for the friction coupling, which comprises an annular chamber formed in one of the rotatable parts and containing a highly viscous fluid. A rotational member is arranged in the annular chamber and is drivingly connected to the other one of the rotatable parts. The actuating device, when the rotatable parts rotate relative to one another, causes an increase in pressure of the highly viscous fluid for the purpose of loading the friction coupling. When the relative rotation between the rotatable parts exceeds a given value, the increase in pressure is checked to limit the torque transferred through the friction coupling.

Abstract: On a frictional engage surface of one of inner and outer clutch plates constructing a wet-type multi-disk clutch, a plurality of convex ridges are formed at an infinitesimal predetermined interval distance. Lubricating oil is kept between the convex ridges, so that the wedge operation in oil can be reduced, whereby the torque transfer characteristic can be improved. Further, a height of the convex ridge is set equal to or more than 1 .mu.m and the interval distance of the convex ridge is set equal to or less than 600 .mu.m, preferably.In the configuration of the clutch plate, it is made of steel as a substrate. Further, a nitrogen diffusion layer, a nitrided layer and an oxidation tunic is formed on said nitrided layer are formed on the substrate in its order therefrom.

Abstract: A rotation transmission device including a clutch having an inner member, an outer ring, and engaging elements provided between the inner member and the outer ring for selective transmission and shutoff of rotation power between the inner member and the outer ring, and an electromagnetic clutch having an electromagnetic coil for locking and disengaging the clutch. When the clutch is not engaged, a current of a lower level than required to lock the clutch is supplied to the electromagnetic coil of the electromagnetic clutch to shorten the response time. In another method, when DIRECT-CONNECT 4WD mode is selected, a current is intermittently supplied to an electromagnetic coil to reduce power consumption and heat buildup.

Abstract: A coupling device for transmitting torque between a first part and a second part which are rotatable relative to one another is disclosed. The coupling device comprises a multi-plate coupling unit with axially alternating arranged first plates and second plates. The first plates are each connected in a rotationally fixed manner to one of the first part or the second part and the second plates are each connected in a rotationally fixed manner to the other of the first part or the second part. The coupling device further comprises an actuating assembly for axially loading the multi-plate coupling unit by means of a setting piston. The multi-plate coupling unit also comprises a first annular chamber filled with a highly viscous fluid and delimited by the setting piston, and a rotational member arranged in the annular chamber. The first annular chamber is formed in one of the first or second parts with the rotational member being connected in a rotationally fixed manner to the other of the first or second part.

Abstract: A hydraulic coupling is disclosed for use in motor vehicle driveline applications to rotatively couple a pair of rotary members. The hydraulic coupling includes a multi-plate clutch assembly operatively connecting the two rotary members and an actuator assembly for actuating the clutch assembly in response to and as a function of speed differentiation between the two rotary members. The actuator assembly includes a hydraulic pump, a piston disposed in a piston chamber, and a fluid control system for controlling the fluid pressure supplied to the piston chamber by the hydraulic pump to control the clutch engagement force exerted by the piston on the clutch assembly. The fluid control system includes a pressure relief valve operable for limiting the fluid pressure in the piston chamber to a predetermined maximum pressure value.

Abstract: A driving force transmission system comprising: a coupling case and a shaft arranged rotatably relative to each other; a pilot clutch and a main clutch for controlling a torque transmission between the coupling case and the shaft; an electromagnet for controlling the actions of the pilot clutch and the main clutch; and oil for retaining the functions of the pilot clutch and the main clutch. This system further comprises a coupling case, a shaft, a rotor, an X-ring and an O-ring for isolating a coupling oil chamber, in which the pilot clutch and the main clutch are arranged, liquid-tight from the surrounding space.

Abstract: An electromagnetic clutch assembly for motor vehicle transfer cases and the like includes an electromagnetic operator and a disc pack clutch assembly disposed on opposite sides of a chain drive sprocket. The clutch pack assembly is driven by a primary output shaft of the transfer case and transfers energy to the chain drive sprocket and thence to a secondary output shaft. The disc pack clutch assembly is actuated by the clutch operator which generates a compressive force which is transferred to the clutch pack assembly by a plurality of axially disposed pins received within complementary passageways in the chain drive sprocket.

Abstract: A center differential device (17) for use in a four wheel drive system, the device including a viscous coupling (29), a ball ramp actuator (31), and a clutch pack (33). Under normal driving conditions, most of the torque is transmitted to the front drive wheels (11), and the device (17) rotates as a unit. If the front wheels (11) begin to slip, the input shaft (15) and input coupling member (35) rotate faster than the output coupling member (43), thus transmitting torque to the output coupling member (43). This torque is transmitted to the first ramp plate (51) of the ball ramp actuator (31), displacing the actuator from its neutral position (FIG. 3), such that the second ramp plate (52) begins to load the clutch pack (33) and transmit torque from the housing (25) to the output shaft (19), and from there to the rear drive wheels (23).

Abstract: A clutch assembly for disposition in a motor vehicle drive line includes an internal reaction force circuit. The clutch assembly includes a multiple disc friction clutch disposed adjacent an operator assembly which selectively applies force to the friction clutch to selectively transfer torque therethrough. The clutch components are disposed between a flange and a stop on an elongate member which functions as a reaction force member to self-contain the reaction force from the clutch operator. The clutch finds particular application in motor vehicle drive line components such as a rear (secondary) axle wherein it is disposed in pairs to independently control torque supplied to each axle and in applications where it is advantageous to contain or ground the reaction force generated by and associated with the clutch operator compactly within the clutch structure rather than its housing.

Abstract: A transmission for changing a path to transmit a torque by changing the state of torque transmission to a rotary member, comprising: an active material for changing its state when fed with an electric signal; and a coupling mechanism for effecting or intercepting the torque transmission to the rotary member in accordance with the state change of the active material.

Abstract: A friction brake assembly for applying a braking torque to a rotating shaft such as a transmission output shaft utilizing a primary ball ramp mechanism having a control ring and activation ring with opposed variable depth grooves and rolling members disposed therebetween to load a friction brake in response to a secondary ball ramp mechanism which creates a braking torque on the control ring to activate the primary ball ramp mechanism in response to the rotation of a control lever. Rolling members disposed in opposed variable depth grooves formed in the control lever and a control plate force the control plate towards a housing extension thereby applying a friction force to a clamp ring where the clamp ring is connected to the control ring of the primary ball ramp mechanism using a flex extension to allow relative axial movement between the clamp ring and the control ring. In this manner, the friction brake assembly of the present invention can function as a vehicle parking brake.

Abstract: A coupling device with two parts which are coaxially rotatable relative to one another, comprising a friction coupling whose friction plates are alternately connected to each of the rotatable parts. Further the coupling device comprises an actuating device for the friction coupling, which comprises an annular chamber formed in one of the rotatable parts and containing a highly viscous fluid. A rotational chamber is arranged in the annular chamber and is drivingly connected to the other one of the rotatable parts. The actuating device, when the rotatable parts rotate relative to one another, causes an increase in pressure for the purpose of loading the friction coupling.

Abstract: An acceleration sensitive double overrunning clutch is directionally preset by a change in speed, i.e., acceleration, rather than relative rotation. The clutch is especially adapted for use in power transmission devices such as motor vehicle transfer cases. The clutch includes a plurality of rollers disposed in a like plurality of spaces having symmetrically arranged oblique walls formed by adjacent portions of an inner member and a concentric outer member. The rollers are arranged within a spacing cage which is coupled to an annular weight. A speed change, i.e., acceleration or deceleration, shifts the weight and presets the cage and rollers to function in their engaged or overrunning modes in one direction or the other depending upon the direction of such acceleration.

Abstract: A multiple-ratio automatic transmission having plural torque delivery paths that are established and disestablished by a roller clutch and brake system. The clutch and brake system establishes and disestablishes torque flow paths while preventing simultaneous clutch or brake engagement. The clutch and brake system is capable of accommodating instantaneous torque reversals during ratio changes. Simplified clutch and brake system actuators trigger the application and release of the clutches and brakes during ratio changes.

Abstract: A two-way clutch comprising an input system rotational member (10) adapted to be rotatably driven by a driving source, an output system rotational member (60, 140) for taking out outwardly a torque transferred from the input system rotational member (10), and a torque transferring member (50, 150a,150b) interposed between the input system rotational member (10) and the output system rotational member (60, 140) for selectively making the two rotational members engage and disengage each other, wherein in order to perform securely torque transfer and cut off between the input and output systems and avoid any influence of an external force applied from the output system during torque transfer, the torque transferring member (50, 150a, 150b) is adapted to transfer torque in both forward and backward rotating directions while it engages the input system rotational member (10) and the output system rotational member (60, 140) and the output system rotational member (60, 140) is adapted to freely rotate only when the

Abstract: A power transmitting system having an input shaft, a driven bevel gear, a follower bevel gear and a clutch drive shaft accommodated in center casings. Left and right electromagnetic clutches connected to the clutch drive shaft are accommodated in left and right side casings. Oil for lubricating the electromagnetic clutches is supplied from an oil pump accommodated in the center casings and driven by the clutch drive shaft through oil passages and axially defied in the clutch drive shaft and left and right output shafts. Thus, the length of the oil passages for supplying the oil from the oil pump to the clutches can be minimized to provide a reduction in size of the power transmitting system.

Abstract: A one way drive device for transmitting torque from a rotational input to a rotational output when the device is driven in a counterclockwise torque transmitting rotational direction by the rotational input. The device allows the rotational input to freely rotate in a clockwise overrun direction relative to the rotational output. The one way drive device includes a dog clutch to transmit torque when driven in the torque transmitting direction and a ratchet clutch to provide the overrun function.

Abstract: In a power transmitting system, a clutch drive shaft driven through bevel gears and by an input shaft is laterally extensive and left and right electromagnetic clutches are disposed between opposite ends of the clutch drive shaft and left and right output shafts, respectively. A clutch body heated during the transmission of a power is disposed at a laterally outer location of the system to provide enhanced heat-radiatability, and an annular solenoid is disposed inside the clutch body. A bearing for supporting each of the opposite ends of the clutch drive shaft is disposed radially inside the solenoid. Thus, the lateral dimension of the power transmitting system is reduced.

Abstract: A coupling assembly has at least one friction coupling unit which comprises a driveable housing and a hub to be driven, and having differential-speed-dependent actuating means operating by a pressure agent and comprising a pump unit. The pump unit comprises housing parts and hub parts, which housing parts are rotatable relative to said hub parts with the one part of the pump unit being connected in a rotationally fixed way to the housing of the friction coupling unit and the other parts of the pump unit being connected in a rotationally fixed way to the hub of the friction coupling unit. The hub of the at least one friction coupling unit is receiving an outer joint part of a constant velocity universal joint.

Abstract: A coupling device with two parts which are coaxially rotatable relative to one another, comprising a friction coupling whose friction plates are alternately connected to each of the rotatable parts. Further the coupling device comprises an actuating device for the friction coupling, which comprises an annular chamber formed in one of the rotatable parts and containing a highly viscous fluid. A rotational chamber is arranged in the annular chamber and is drivingly connected to the other one of the rotatable parts. The actuating device, when the rotatable parts rotate relative to one another, causes an increase in pressure for the purpose of loading the friction coupling.

Abstract: A differential device (17) for use in a four wheel drive system, the device including a viscous coupling (29), a ball ramp actuator (31), and a clutch pack (33). Under normal driving conditions, most of the torque is transmitted to the front drive wheels (11), and the device (17) rotates as a unit. If the front wheels (11) begin to slip, the input shaft (15) and input coupling member (35) rotate faster than the output coupling member (43), thus transmitting torque to the output coupling member (43). This torque is transmitted to the first ramp plate (51) of the ball ramp actuator (31), displacing the actuator from its neutral position (FIG. 3), such that the second ramp plate (52) begins to load the clutch pack (33) and transmit torque from the housing (25) to the output shaft (19), and from there to the rear drive wheels (23).

Abstract: A wrap spring operating mechanism for use in a random start/stop clutch, brake, or combined clutch/brake assembly limits the rate of acceleration or deceleration of the second member relative to the first member when the assembly is engaged. The assembly includes a first member, a second member, and a helical spring wrapped about adjacent portions of the first and second members. An annular control collar is disposed circumferentially about portions of the first and second members. The wrap spring has a first end that is connected to the first member and a second end that is connected to the control collar. An annular armature is connected to the control collar for rotational movement therewith and for relative axial movement. An annular rotor is disposed circumferentially about and connected to the second member. An annular friction ring is disposed within a recess formed in the rotor. The friction ring is formed from a material having a relatively low coefficient of friction, preferably about 0.

Abstract: A clutch mechanism for a vehicle drive train wherein a drive member and driven member are inter-engaged by pawls. In the preferred embodiment the driven member surrounds the drive member in concentric relationship and provides facing surfaces that are configured to receive pairs of pawls or pawl portions selectively extended from the drive member surface to the driven member surface. A control member is mounted on the drive member with limited rotation relative to the rotation of the drive member. The control member includes a cam slot and the pawls are provided with laterally extended cam follower tabs that extend into the cam slots. The control member is provided with a rotationally retarding means whereby whichever direction the drive member rotates, the control member is shifted to the trailing position within the range of permitted rotation.

Abstract: A coupling has two parts supported one inside the other, which are rotatable relative to one another around a common longitudinal axis. Together, the parts form a chamber filled with a highly viscous fluid and which is sealed by an axially movable piston. The coupling also includes a friction coupling with friction elements, having a spring assembly which is supported on a stop part and acting on a pressure plate. When the piston is in a position of rest, the friction elements of the friction coupling are held against a further stop part under pretension generated when the relative rotation begins. In the case of axial displacement, the piston displaces the pressure plate against the force of the spring assembly towards the first stop part, with there being provided an axial gap between the piston in a position of rest and a further stop part which is displaceable towards the first stop part.

Abstract: A vehicle driveline clutch using a ball ramp actuator supplying a clamping force on a clutch disc in response to an electromagnetic field where the clutch clamping force is maintained and increased with clutch slip using a plurality of one-way clutches acting in a pair of planetary gearsets with a one-way clutch acting on each planet gear and supported on a carrier ring which is frictionally connected to a ball ramp control ring upon energization by a clutch coupling with an electrical coil thereby creating relative rotational motion between the control ring and an actuation ring causing a plurality of rotational elements to travel along identical opposed variable depth ramps thereby creating an axial separation force between the control ring and the actuation ring generating the clamping force on the clutch disc.

Abstract: A clutch assembly using a ball ramp actuator supplying a clamping force on a clutch disc in response to an electromagnetic field where the clutch clamping force is maintained and increased with clutch slip using a ball ramp mechanism having a control ring and an actuation ring. A bias spring acting to maintain contact between a clutch member and the coil plate of the control clutch. Activated by a control clutch having a response to electrical current introduced into a coil thereby creating an electromagnetic field in a coil pole which attracts a coil plate which in turn applies a cone clutch thereby introducing a rotational torque on the control ring to activate the ball ramp mechanism. The bias spring is used to force the clutch plate toward the coil pole thereby minimizing the air gap between the clutch plate and coil pole thereby providing a more controllable engagement of the clutch assembly.

Abstract: There is disclosed a drive force transmission apparatus which includes a first pressing-force generation unit for generating a pressing force in accordance with a rotational speed difference between driving and driven shafts, and a frictional clutch which is brought into an engaged state by the pressing force generated by the first pressing-force generation unit in order to transmit torque in accordance with the rotational speed difference between the driving and driven shafts. The drive force transmission apparatus further includes a second pressing-force generation unit disposed opposite to the first pressing-force generation unit with respect to the frictional clutch. When needed, the second pressing-force generation, unit is operated to bring the frictional clutch into a firmly engaged state, thereby improving the traveling performance of the vehicle under severe traveling conditions, such as an attempt to extract a wheel trapped in a gutter or the like, traveling on a rough road, traveling on sand, etc.

Abstract: In a transmission inertia brake a ball ramp mechanism is used to load a clutch pack to slow a rotating transmission shaft where the clutch pack is carried on a one piece drive assembly having a gear section for meshing with a transmission gear, an extension section for engaging a thrust plate in an isolator assembly, a clutch section for engaging plurality of driven clutch plates in the clutch pack and a bearing section for rotational support within a brake housing. An armature having an angled peripheral surface engages a mating friction surface formed in an end plate to form a core clutch, the armature being magnetically pulled upon energization of an electrical coil energized by a power signal from a control unit supplied through a sealed electrical connector thereby introducing a frictional braking force on the armature to activate the ball ramp mechanism. The armature is nonrotatably connected to the control ring of the ball ramp mechanism through at least one connecting pin.

Abstract: A vehicle driveline clutch using a ball ramp actuator supplying a clamping force on a clutch disc in response to an electromagnetic field where the clutch clamping force is maintained and increased with clutch slip using a plurality of one-way clutches acting in a pair of planetary gearsets with a one-way clutch acting on each planet gear and supported on a carrier ring which is frictionally connected to a ball ramp control ring upon energization by a clutch control unit of an electrical coil thereby creating relative rotational motion between the control ring and an actuation ring causing a plurality of rolling elements to travel along identical opposed variable depth ramps thereby creating an axial separation force between the control ring and the actuation ring generating the clamping force on the clutch disc.

Abstract: A friction clutch assembly in an automotive vehicle transmission is located between an engine-driven input shaft and a torque input shaft for a multiple ratio transmission. A clutch spring normally applies a clutch engaging force to the clutch assembly, thus establishing a torque flow path between the input shaft and the multiple ratio gearing. An electromechanically actuated ball ramp mechanism applies a friction clutch release force to the friction clutch assembly, thereby interrupting the torque flow path between the transmission input shaft and the multiple ratio gearing. An electromagnetic clutch actuator for the ball ramp mechanism, when it is energized, actuates the ball ramp mechanism to disengage the friction clutch. One element of the ball ramp mechanism is grounded to a transmission housing when the electromagnetic actuator is energized.

Abstract: A multiple disc clutch pack includes a pilot magneto-rheological operator which controls operation of an associated ball ramp operator which, in turn, compresses a clutch pack to selectively transfer torque between and input member and an output member. The pilot operator includes an electromagnetic coil disposed proximate a magneto-rheological fluid contained within a chamber of a pilot clutch. Activation of the electromagnetic coil creates a magnetic flux which travels through the magneto-rheological fluid and couples the fluid clutch members, creating drag and relative rotation between members of the ball ramp operator. Such relative rotation of the ball ramp operator selectively compresses the clutch pack and transfer torque from the input member to the output member.

Abstract: A first ball ramp actuator having a control ring acting with an activation ring to supply an axial clutch clamping force in a vehicle driving mode and a second ball ramp actuator using the control ring acting with a clutch pressure plate to supply an axial clutch clamping force in a vehicle coast mode where one side of a one-way clutch is attached to the control ring and another side is attached to a support bracket that is frictionally coupled to a transmission input shaft to maintain an energized rotational relationship with the activation ring when in the coast mode.