Abstract: Damping device to impose a reaction to the displacement of a manual operating device (28), said device comprising at least one chamber containing the magneto-rheological fluid, one or two means of generating a variable magnetic field (6.1, 6.2) in the magneto-rheological fluid so as to modify its apparent viscosity, one element (4) free to move in translation capable of shearing the magneto-rheological fluid and designed to be mechanically connected to the manual operating device (28), said mobile element (4) comprising a blade with a longitudinal axis (Y) comprising holes and/or recesses and/or projections.

Abstract: A method for ascertaining a rotational speed parameter for determining a setpoint torque for driving a drivetrain. The drivetrain comprises a first and at least one second drive assembly for driving a hybrid vehicle. The first drive assembly can be coupled to the drivetrain by means of a clutch. The second drive assembly is mechanically coupled to the drivetrain. When the hybrid vehicle is being driven by means of at least the first drive assembly, the rotational speed parameter corresponds to the value of a shaft rotational speed. When the hybrid vehicle is being driven only by means of the second drive assembly, the rotational speed parameter corresponds to the value of a determined rotational speed.

Abstract: A housing forms a fluid chamber in an inside of the housing. A magneto-rheological fluid includes a plurality of magneto-rheological particles dispersed in the magneto-rheological fluid and is filled in the fluid chamber. A partition structure partitions the fluid chamber between a radially outer region, in which the magnetic portion is exposed, and a radially inner region, which is located on a radially inner side of the radially outer region in a radial direction of a rotatable brake body, during rotation of the rotatable brake body.

Abstract: Magnetorheological transmission device and method for influencing the coupling intensity of two components, which can be coupled and whose coupling intensity can be influenced. A channel is provided, which contains a magnetorheological medium with magnetically polarizable particles, which can be influenced by a magnetic field. A magnetic field generating unit generates a magnetic field in the channel in order to influence the magnetorheological medium in the channel. A body is disposed in the channel. A free distance between the body and the component is at least ten times greater than a typical mean diameter of the magnetically polarizable particles in the magnetorheological medium. A space with magnetorheological medium is disposed between the body and a component. The magnetic field is applied to the region in order to optionally chain together the particles and/or wedge or release them with the body.

Abstract: In a control of a vehicular automatic transmission, an engaging device provided in a power transmission path between an engine and driving wheels is brought into a slipping state or a release state when a certain neutral control condition is satisfied while a shift lever is placed in a running position, the engaging device is engaged so as to increase a torque transmission capacity thereof when a certain neutral control cancellation condition is satisfied during neutral control under which the engaging device is in the slipping state or the release state, and an engaging pressure of the engaging device is held at a constant pressure level for a given period of time when an accelerator pedal is depressed while the engaging device is engaged so as to increase the torque transmission capacity thereof.

Abstract: An engine clutch is provided. The clutch includes a drive shaft rotated by the engine, an eccentric shaft selectively rotated by the drive shaft, a clutch fluid, a plurality of pistons, and a fluid regulator. The eccentric shaft is positionable in an opening of the drive shaft for rotation thereby. The eccentric shaft has cylinders extending radially therethrough and a central channel extending longitudinally therethrough. The clutch fluid flows between the cylinders and channel. Each piston is slidably positionable in a cylinder in response to flow of clutch fluid. The pistons have an outer end in constant contact with the drive shaft via a bearing. The fluid regulator is positionable in the central channel for selectively restricting flow of clutch fluid whereby rotational speed of the eccentric shaft is adjusted. The eccentric shaft is connectable to a device, such as a fan, for rotation therewith.

Abstract: A vehicle has a multi-gap magnetorheological fluid (MRF) clutch connecting rotatable input and output members, and includes a drum connected to the output member and a rotor connected to the input member. The drum contains a magnetically-permeable stator and a magnetic core, while the rotor has a magnetically-permeable member extending axially into the drum to define an outer working gap in conjunction with the stator and an inner working gap in conjunction with the magnetic core. MR fluid fills the working gaps, and a magnetic field generator or electromagnet induces a magnetic field when electrical current is passed through a field coil therein to change an apparent viscosity of the MR fluid. The inner and outer working gaps have a predetermined inner to outer gap thickness ratio balancing the slip power dissipation per unit volume in each of the working gaps.

Abstract: A torque-limited coupling element is described, comprising an input part and an output part, each mounted rotatably about a common rotational axis, and at least one connecting means. If a predeterminable limit torque acting between the input part and output part is exceeded, the connection means can be transferred from a first position, in which the connecting means non-rotatably connects the input part and output part to one another forming a positive engagement, into a second position, in which the input part and output part are mounted rotatably relative to one another. Furthermore, a method for torque-limited coupling and uses for such a coupling element are described.

Abstract: An electromagnetic friction clutch (1) is proposed having two clutch plates (2, 8) which have concentrically circular, magnetically soft ring areas (3a-3c, 9a-9d) which are at least partially magnetically insulated from one another, which friction clutch (1) transmits comparatively large torques while having a compact design. For this purpose, pole faces (4a-4f, 10a-10f) which, when viewed in the radial cross section, oscillate in the axial direction are formed at the magnetically soft ring areas (3a-3c, 9a-9d).

Abstract: A device for transmission and/or generation of torque having a driveshaft and having a driven shaft acted upon by field-excited forces of a magnetorheological medium, the driveshaft terminates in a flange in a housing, at least one cylinder is arranged on the flange (7), and the cylinder extends over the driven shaft coaxially while forming a gap which is filled with the magnetorheological medium.

Abstract: The present invention relates to a magnetorheological torque transmission device comprising two device parts separated by at least one transmission gap for transmitting torque, said gap being fillable and/or filled with a magnetorheological material, rotating relative to each other about an axis of rotation, wherein the magnetic circuit system of the torque transmission device comprises at least one permanent magnet having variable magnetization in addition to at least one electromagnet for generating the magnetic flux in at least one part of the transmission gap, wherein the electromagnet and the permanent magnet are designed and disposed such that the magnetization of the permanent magnet can be adjusted by changing the coil current of the electromagnet. The present invention further relates to a correspondingly designed force transmission device.

Abstract: A marine transmission provides first and second drive gears that have first and second driving surfaces in contact with first and second quantities of rheological fluid. First and second driven surfaces of a propeller shaft are also in contact with the rheological fluids within first and second cavities. Torque is transmitted between the drive gears and the propeller shaft through the increase in viscosity of the rheological fluid. A dog clutch can also be provided in order to lock the propeller shaft to the driving one of the first and second drive gears after the rheological fluid is used to spin up the propeller shaft to the appropriate speed.

Abstract: A viscous fluid clutch for use as a clutch for a cooling fan for a vehicle, the clutch includes an input shaft, a rotor assembly, a first housing portion, a second housing portion, a coil assembly, and a brush box. The rotor assembly is coupled to the input shaft. The first housing portion is coupled to the second housing portion and the second housing portion is rotatably disposed on the input shaft. The first and second housing portions define a fluid reservoir for receiving the rotor assembly and a viscous fluid, preferably of the magnetorheological type. The coil assembly is coupled to the first housing portion. The brush box is operably coupled to the coil assembly. When the coil assembly is energized by the brush box, a magnetic field is created that acts upon the magnetorheological fluid to vary the torque transfer of the input shaft to the housing and the fan connected thereto.

Abstract: A magnetorheological clutch includes a primary part, a secondary part and a magnet for the generation of a magnetic field. The primary part and the secondary part are rotatable relative to one another around an axis of rotation of the clutch, with the primary part being rotationally fixedly connected to at least one disk. The disk is surrounded by coupling gaps in which a magnetorheological medium is arranged. The thickness of the at least one disk along the coupling gap has a value of approximately 0.4 mm to approximately 1 mm, with the at least one disk being formed along the coupling gaps without material interruptions.

Abstract: A viscous fluid clutch for use as a clutch for a cooling fan for a vehicle, the clutch includes an input shaft, a rotor assembly, a first housing portion, a second housing portion, a coil assembly, and a brush box. The rotor assembly is coupled to the input shaft. The first housing portion is coupled to the second housing portion and the second housing portion is rotatably disposed on the input shaft. The first and second housing portions define a fluid reservoir for receiving the rotor assembly and a viscous fluid, preferably of the magnetorheological type. The coil assembly is coupled to the first housing portion. The brush box is operably coupled to the coil assembly. When the coil assembly is energized by the brush box, a magnetic field is created that acts upon the magnetorheological fluid to vary the torque transfer of the input shaft to the housing and the fan connected thereto.

Abstract: A viscous fluid clutch for use as a clutch for a cooling fan for a vehicle , the clutch includes an input shaft, a rotor assembly, a first housing portion, a second housing portion, a coil assembly, and a brush box. The rotor assembly is coupled to the input shaft. The first housing portion is coupled to the second housing portion and the second housing portion is rotatably disposed on the input shaft. The first and second housing portions define a fluid reservoir for receiving the rotor assembly and a viscous fluid, preferably of the magnetorheological type. The coil assembly is coupled to the first housing portion. The brush box is operably coupled to the coil assembly. When the coil assembly is energized by the brush box, a magnetic field is created that acts upon the magnetorheological fluid to vary the torque transfer of the input shaft to the housing and the fan connected thereto.

Abstract: An apparatus is provided having an active material forming a surface thereof in contact with a rheological fluid. The active material is controllable to vary a surface geometry thereof between a rough or nonsmooth surface geometry to increase drag, and achieve an increase in stress transmitted through the fluid, when a field is applied, while allowing a smooth surface geometry and an associated reduction in stress transmitted through the fluid when the field is removed. A method of enhancing performance of an apparatus that includes a rheological fluid is also provided.

Abstract: Magneto-rheological clutch and wheel transmission apparatuses and methods are provided. According to one aspect, a magneto-rheological clutch system can include first and second drive members and first and second driven members. A first gap can be present between the first drive and first driven members. A second gap can be present between the second drive and second driven members. A drive wheel and a snow blower impeller can be connected to the first and second driven member, respectively. First and second MR fluids can be disposed in the first and second gaps, respectively. A first magnetic field can be applied to the first MR fluid for engaging the drive wheel. A second magnetic field can be applied to the second MR fluid for engaging the snow blower impeller. The provided apparatuses and methods can also be applied to mower blades and wheels.

Abstract: An electromagnetically actuated viscous clutch assembly includes a rotor arranged relative to an axis of rotation, an electromagnetic coil for generating magnetic flux, a housing positioned adjacent to the rotor to create a fluid working chamber therebetween with the housing and the rotor being selectively rotatable relative to one another, an insert extending through the housing and configured to conduct magnetic flux from the electromagnetic coil along a flux path, a valve assembly electromagnetically linked to the insert along the flux path for selectively controlling fluid flow into the working chamber to selectively engage the rotor and the housing, and a plurality of recesses defined in a portion of the housing located at an interior of the flux path to reduce eddy currents.

Abstract: A power transmission apparatus includes a drive roller and a driven roller made of magnetic material, which are rotatable about different axes, and which are provided with a gap therebetween, a case enclosing the rollers, an input shaft and an output shaft connected coaxially with the rollers through the case, respectively, and a magnetic fluid housed in the case to fill the gap. The apparatus includes an electromagnetic coil for generating magnetism, and a magnetic path of the magnetism generated by the electromagnetic coil is formed so that a magnetic field is generated from the drive roller or the driven roller toward the driven roller or the drive roller via the gap.

Abstract: A twin-clutch device that selectively transmits torque from a driving wheel to a first driven wheel and/or a second driven wheel is provided. The first and second driven wheels are arranged respectively on both sides of the driving wheel, a functional fluid that decreases its flowability as an applied stimulus is increased and that increases its flowability as the applied stimulus is reduced fills gaps between the driving wheel and the first and second driven wheels, the driving wheel includes a stimulus generating member electrically controlled to generate a stimulus, and flowability of the functional fluid between the driving wheel and one of the first and second driven wheels is decreased with an increase in stimulus applied to the functional fluid by the stimulus generating member to couple the driving wheel to the one of the first and second driven wheels, thus allowing torque transmission therebetween.

Abstract: A differential assembly includes an axle, a differential, a differential lock assembly, a selector, and a coupler. The differential is coupled with the axle and is configured to facilitate operation of the axle at an axle speed. The differential lock assembly is associated with the differential and is movable between locked and unlocked positions. The selector is movable between lock-initiate and unlock-initiate positions. The coupler is configured to selectively couple the differential lock assembly and the selector. The coupler is configured for operation in deactivated and activated modes. When the coupler is in the deactivated mode, the differential lock assembly and the selector are decoupled from each other. When the coupler is in the activated mode, the differential lock assembly and the selector are coupled together.

Abstract: Magneto-rheological brake-clutch apparatuses and methods are provided. According to one aspect, a magneto-rheological brake-clutch can include a drive member and a driven member spaced from the drive member with a gap defined between the drive and driven members. A first quantity of MR fluid can be disposed in the gap. A brake assembly can define a chamber having a second quantity of MR fluid disposed therein and having a braking structure positioned in the chamber and connected to the driven member. A magnetic field generation assembly can be configured to selectively apply a magnetic field to the first quantity of MR fluid for controlling engagement of the driven member with the drive member. The assembly can be configured to selectively apply a magnetic field to the second quantity of MR fluid for controlling engagement of the braking structure with the brake assembly to brake the driven member.

Abstract: A magnetorheologic clutch includes a stationary part, a rotatable primary part having primary discs, a secondary part having secondary discs, and a chamber containing magnetorheologic fluid formed between the primary and secondary parts that is exposed to an adjustable magnetic field. To make a magnetorheologic clutch as small as possible which is capable of transmitting a peak torque at a minimum power consumption and which is easily controlled, at least one magnet coil is axially arranged before or after the discs and encompasses a first U-shaped cylinder head whose two surfaces are arranged on the side of the discs in a parallel thereto. A second cylinder head is disposed on the side of the discs opposite with respect to the first cylinder head. Areas of the secondary part are radially disposed inside and outside the discs which are made of a low-permeability magnetic material.

Abstract: A magnetorheological clutch comprises a stationary part, a rotating primary part with primary laminated strips and a secondary part with secondary laminated strips, whereby a controllable magnetic field acts upon the magnetorheological fluid. The aim of the invention is to allow transmission of a highest possible torque in a smallest possible space and with minimal power consumption. Said aim is achieved, whereby a number of solenoid coils, each having a first yoke with a substantially radial winding axis, are alternately oppositely polarized; the first yokes have cylindrical front faces, whereby the magnetic field lines radially enter and exit said yokes, the primary laminated strips and secondary laminated strips form closed cylindrical envelopes and second outer and inner yokes are provided radially outside of and radially inside the first yokes, whereby the magnetic field lines radially enter the second yokes and radially exit said yokes in the opposite direction.

Abstract: Provided is an actuator, comprising a motor/generator element and a clutch/brake element. The motor/generator element comprises a stator made of a high magnetic permeable material, an outer coil being wound around the stator; a rotor made of a high magnetic permeable material and with a plurality of permanent magnets fixed thereon; and a cavity configured to receive a fluid. The clutch/brake element is arranged in the cavity. An inner coil is wound around the clutch/brake element. The fluid is capable of producing a shear stress in response to an electromagnetic field induced from the inner coil.

Abstract: The present invention relates to a magnetorheological torque transmission device. The same has two device parts rotatable relative to each other about a rotational axis (R) through a torque transmission gap (2), which can be filled and/or is filled at least partially with a magnetorheological material, and is characterized in that the magnetic circuit system of the torque transmission device configured for generating the magnetic flux in the torque transmission gap (2) comprises at least one permanent magnet (4) in addition to a solenoid (1). Advantageously said magnetic circuit system further comprises at least one non-magnetic insert (5, 6).

Abstract: A power transmission apparatus includes a drive roller and a driven roller made of magnetic material, which are rotatable about different axes, and which are provided with a gap therebetween, a case enclosing the rollers, an input shaft and an output shaft connected coaxially with the rollers through the case, respectively, and a magnetic fluid housed in the case to fill the gap. The apparatus includes an electromagnetic coil for generating magnetism, and a magnetic path of the magnetism generated by the electromagnetic coil is formed so that a magnetic field is generated from the drive roller or the driven roller toward the driven roller or the drive roller via the gap.

Abstract: A vehicle has a multi-gap magnetorheological fluid (MRF) clutch connecting rotatable input and output members, and includes a drum connected to the output member and a rotor connected to the input member. The drum contains a magnetically-permeable stator and a magnetic core, while the rotor has a magnetically-permeable member extending axially into the drum to define an outer working gap in conjunction with the stator and an inner working gap in conjunction with the magnetic core. MR fluid fills the working gaps, and a magnetic field generator or electromagnet induces a magnetic field when electrical current is passed through a field coil therein to change an apparent viscosity of the MR fluid. The inner and outer working gaps have a predetermined inner to outer gap thickness ratio balancing the slip power dissipation per unit volume in each of the working gaps.

Abstract: The invention relates to the use of an electric, hydrodynamic or electromagnetic brake for reducing the rotational speed of a drive-side shaft of a gear mechanism.

Abstract: A vehicle differential assembly is provided that includes a differential driven by an input and adapted to allow differing rotational speed between a pair of outputs. The differential includes a gear assembly connected to the outputs and a hydraulically-actuated clutch for selectively and variably coupling the outputs. A hydraulic pump is adapted to generate hydraulic fluid pressure for engagement of the hydraulically-actuated clutch. A variable-engagement clutch is operatively connected to the input and the hydraulic pump such that the input selectively drives the hydraulic pump during engagement of the clutch to provide hydraulic fluid pressure to the hydraulically-actuated clutch. A torque coupling including a variable-engagement clutch is also provided.

Abstract: The safety device mainly contains a main controller, a detector, and an emergency braking member. The main controller contains a detection member connecting the detector, an alarm member producing visual or audible alarm, and a driving member for activating the emergency braking member to reverse or stop the motor of the machine tool. The detection member could be an electrostatic detection unit, or a capacitance detection unit, or a combination of the two. The detector is positioned on a top surface of a platform and in front of a saw of the machine tool. The detector could also be part of an axle of the saw so that the saw is effectively an extension of the detector and provides both cutting and safety functions.

Abstract: Magneto-rheological clutch and wheel transmission apparatuses and methods are provided. According to one aspect, a magneto-rheological clutch system can include first and second drive members and first and second driven members. A first gap can be present between the first drive and first driven members. A second gap can be present between the second drive and second driven members. A drive wheel and a snow blower impeller can be connected to the first and second driven member, respectively. First and second MR fluids can be disposed in the first and second gaps, respectively. A first magnetic field can be applied to the first MR fluid for engaging the drive wheel. A second magnetic field can be applied to the second MR fluid for engaging the snow blower impeller. The provided apparatuses and methods can also be applied to mower blades and wheels.

Abstract: A fast turn-off and fast turn-on circuit (10) providing at least one power source (12, 20), at least one switching device (14, 22), a coil (16), and at least a first voltage control device (18). The at least one switching device (14, 22) is connected to the at least one power source (12, 20) for selectively connecting the at least one power source (12, 20) to portions of the circuit (10). An electrical current from at least one power source (12, 20) charges the coil (16) and creates an electromagnetic field when the at least one switching device (14, 22) is in a closed position and connects the at least one power source (12, 20) with the coil (16). The first voltage control device (18) limits a voltage in the circuit (10) when the electromagnetic field decays.

Abstract: Disclosed is a magnetorheological clutch comprising a stationary part (1), a rotating primary part (2) with primary lamellae (7), and a coaxially rotating secondary part (3) with secondary lamellae (20). An adjustable magnetic field acts upon the magnetorheological fluid. In order to be able to transmit the greatest possible torque in a minimum of space and at minimal power consumption, at least one magnet coil (25) encompassing a first yoke (24a, 24b) is disposed such that primary lamellae (7, 7?) and secondary lamellae (20, 20?) are located on both sides thereof. The lamellae are made of a material which is provided with moderate magnetic permeability and allows limited short-circuit flux. A second yoke (27, 27?) having a face (32, 32?) that extends parallel to the lamellae adjoins the outermost lamella on both sides, “outermost” being in relation to the axial direction.

Abstract: The inventive magnetorheological clutch comprises a fixed part (1), a primary rotatable part provided with primary discs (4) and a secondary part (6) provided with secondary discs (14), wherein a magnetorheological fluid-containing space (19) is formed and a magnetic field acts on said magnetorheological fluid. The aim of said invention is to minimise the assembly space and the current consumption and, for this purpose is characterised in that at least one solenoid coil (10) comprising a yoke (9) is arranged upstream or downstream of a space (19) surface opposite to the first yoke (9), a second yoke (8) whose front surface (17) is arranged in a parallel position to the discs (4, 14) and the discs (4, 14) are embodied in the form of plates made of a moderate magnetic permeability material in such a way that fluxes are distributed through the discs by magnetic short circuit.

Abstract: A micro device is provided that includes a body defining a chamber for receiving fluid. A rotational element is disposed in the chamber for acting on the fluid. The rotational element is rotatable about an axis in response to a rotating magnetic field. The micro device further includes a clutch mechanism having a first disengaged configuration and a second engaged configuration wherein the clutch mechanism engages the rotational element and prevents rotation of the same.

Abstract: A magnetorheological fan coupling (10) having a fan-drive subassembly (12), an electromagnet subassembly (14), and a magnetic medium (16). The fan-drive subassembly (12) includes an output member (22) and an input member (20) rotatably mounted around the output member (22) with the magnetic medium (16) therebetween. The magnetic medium (16) has a shear stress that can be adjusted by a magnetic flux (24) for transferring torque between the input member (20) and the output member (22). The electromagnet subassembly (14) includes a stationary electromagnet coil (62) for adjusting the shear stress of the magnetic medium (16) and regulating a torque transferred between the input member (20) and the output member (22).

Abstract: A magnetorheological fan coupling (10) having a fan-drive subassembly (12), an electromagnet subassembly (14), and a magnetic medium (16). The fan-drive subassembly (12) includes an output member (22) and an input member (20) rotatably mounted around the output member (22) with the magnetic medium (16) therebetween. The magnetic medium (16) has a shear stress that can be adjusted by a magnetic flux (24) for transferring torque between the input member (20) and the output member (22). The electromagnet subassembly (14) includes a stationary electromagnet coil (62) for adjusting the shear stress of the magnetic medium (16) and regulating a torque transferred between the input member (20) and the output member (22).

Abstract: An apparatus is provided having an active material forming a surface thereof in contact with a rheological fluid. The active material is controllable to vary a surface geometry thereof between a rough or nonsmooth surface geometry to increase drag, and achieve an increase in stress transmitted through the fluid, when a field is applied, while allowing a smooth surface geometry and an associated reduction in stress transmitted through the fluid when the field is removed. A method of enhancing performance of an apparatus that includes a rdeological fluid is also provided.

Abstract: A magnetorheological clutch consists of a stationary part, a primary part and a secondary part, a working space which contains a magnetorheological fluid being formed between primary part and secondary part, in which working space primary discs and secondary discs successively alternate in the radial direction, and a controllable magnetic field acting on the magnetorheological fluid. In order to prevent segregation of the fluid by centrifugal force in a simple type of construction, the working space is L-shaped in longitudinal section, the primary part is a shaft and the secondary part is a pot enclosing the working space, and are of pot-shaped design.

Abstract: The present invention relates to a magnetorheological clutch including a primary part, a secondary part and a magnet for the generation of a magnetic field. The primary part and the secondary part are rotatable relative to one another around an axis of rotation of the clutch, with the primary part being rotationally fixedly connected to at least one disk. The disk is surrounded by coupling gaps in which a magnetorheological medium is arranged. The thickness of the at least one disk along the coupling gap has a value of approximately 0.4 mm to approximately 1 mm, with the at least one disk being formed along the coupling gaps without material interruptions.

Abstract: A system and method for controlling a plurality of accessories associated with a multiple cylinder internal combustion engine having the accessories coupled to an engine crankshaft by an electromagnetic coupling device with a flowable magnetic material disposed between a driving member and a driven member include selectively supplying power to the electromagnetic coupling device in response to at least one operating condition to simultaneously engage or disengage the plurality of engine accessories. Embodiments include a magnetic particle clutch or magnetorheological fluid clutch connected to an engine crankshaft and a plurality of engine accessories that may include an air conditioning compressor, water pump, power steering pump, alternator, and/or supercharger, for example.

Abstract: A magnetorheological clutch comprises a stationary part (1), of a rotatable primary part (2) with primary lamellae (3) and of a secondary part (8) with secondary lamellae (17) which surrounds the primary part (2), there being formed between the primary part (2) and the secondary part (8) a space (28) which contains a magnetorheological fluid, a regulatable magnetic field acting on the magnetorheological fluid.

Abstract: Disclosed is a magnetorheological clutch comprising a stationary part (1), a rotating primary part (2) with primary lamellae (7), and a coaxially rotating secondary part (3) with secondary lamellae (20). An adjustable magnetic field acts upon the magnetorheological fluid. In order to be able to transmit the greatest possible torque in a minimum of space and at minimal power consumption, at least one magnet coil (25) encompassing a first yoke (24a, 24b) is disposed such that primary lamellae (7, 7?) and secondary lamellae (20, 20?) are located on both sides thereof. The lamellae are made of a material which is provided with moderate magnetic permeability and allows limited short-circuit flux. A second yoke (27, 27?) having a face (32, 32?) that extends parallel to the lamellae adjoins the outermost lamella on both sides, “outermost” being in relation to the axial direction.

Abstract: A magneto-rheological coupling (MRC) having an input assembly and an output member. The output member includes a generally cylindrical drum portion and a hub portion extending radially inwardly therefrom. The generally cylindrical drum portion has a low magnetically permeable region having a plurality of passages defined therein. Additionally, a plurality of apertures are defined by the hub portion. The plurality of passages and apertures enhance the flow of magneto-rheological fluid (MRF) within the MRC. The drum portion has a surface treatment of tungsten-carbide to enhance wear resistance. Additionally, the drum portion has an average roughness, or Ra value, of between 10 and 250 microns.

Abstract: A magnetorheological clutch comprises a stationary part (1), of a rotatable primary part (2) with primary lamellae (3) and of a secondary part (8) with secondary lamellae (17) which surrounds the primary part (2), there being formed between the primary part (2) and the secondary part (8) a space (28) which contains a magnetorheological fluid, a regulatable magnetic field acting on the magnetorheological fluid.

Abstract: A novel magnetic friction clutch is disclosed which is capable of relatively high torque transfer for friction discs of a given diameter, compared to prior art magnetic clutches. A friction coating with good magnetic permeability, such as Ferrous Aluminide or the like, is applied to inner and outer annular regions of the three friction discs and increases the frictional coefficient of the discs with little reduction in the clamping force developed through the clutch.

Abstract: A magnetorheological clutch comprises a stationary part, a rotating primary part with primary laminated strips and a secondary part with secondary laminated strips, whereby a controllable magnetic field acts upon the magnetorheological fluid. The aim of the invention is to allow transmission of a highest possible torque in a smallest possible space and with minimal power consumption. Said aim is achieved, whereby a number of solenoid coils, each having a first yoke with a substantially radial winding axis, are alternately oppositely polarized; the first yokes have cylindrical front faces, whereby the magnetic field lines radially enter and exit said yokes, the primary laminated strips and secondary laminated strips form closed cylindrical envelopes and second outer and inner yokes are provided radially outside of and radially inside the first yokes, whereby the magnetic field lines radially enter the second yokes and radially exit said yokes in the opposite direction.

Abstract: A magnetorheological fan coupling (10) having an inverted construction with an input member (18) rotatably mounted to an output member (20). The input member (18) defines a fluid chamber (50) with the output member (20) rotating therein and a magnetic medium (52) between the output member (20) and the input member (18). The coupling (10) further includes an electromagnet subassembly (14) actuated by a controller (82) for adjusting the shear stress of the magnetic medium (52) and regulating the amount of torque transferred from the input member (18) to the output member (20).