Abstract: The invention comprises a retarder system for use with road vehicles. The retarder system discloses an improved vehicular retarder which incorporates the use of a PMG Gear ratio which permits use of a permanent magnet generator on a secondary shaft that is coupled by the gear ratio to a drive train.

Abstract: A damper including a valve movable between an open position and a closed position to selectively alter the compression damping rate of the shock absorber. The valve may include a self-centering feature that operates to keep the valve body centered about the valve shaft. The damper may also include a timer feature, which retains the valve in an open position for a predetermined period of time after it is initially opened.

Abstract: A hydraulic fluid flow passage has a controlled restriction disposed within the passage. The restriction includes a first filter, a second filter and a plurality of particles disposed between the two filters. The particles are either dielectric particles or they are magnetizable particles. The dielectric particles create an electro-rheological fluid between the filters and the magnetizable particles create a magneto-rheological fluid between the filters. The arrangement for the dielectric particles is controlled by an electric field and the arrangement for the magnetizable particles is controlled by a magnetic field.

Abstract: A magnetorheological damper system comprising a reservoir in communication with a damper. The damper comprises a damper cylinder defining a damper chamber, wherein the damper chamber contains a magnetorheological fluid and a movable damper piston. The damper piston comprises at least two coil windings on the outer surface of the damper piston, wherein the damper piston is capable of generating a magnetic field between the damper piston and a wall of the damper cylinder. The reservoir comprises a reservoir cylinder defining a passageway, wherein the reservoir includes a magnetorheological electromagnet capable of generating a magnetic field between the magnetorheological piston and a wall of the passageway. The combination of the an MR reservoir and MR damper leads to a damping system capable of damping a wide range of extreme forces.

Abstract: The invention disclosed is a magnetorheological fluid device offering vibration isolation and broad modulation range damping in a high load carrying and compact form. A cylindrically shaped flexure structure has a bottom cap attached to one end and a top cap attached to the other end. A piston comprising a toroidal displacement body, a central shaft, and intermediate connecting plate, attaches to the top cap. A fluid chamber surrounding and generally conforming to the shape of the toroidal displacement body, is attached to the bottom cap. Two bellows attaching between the piston connecting plate and top and bottom portions of the fluid chamber complete an enclosed volume around the toroidal displacement body and allow frictionless motion of the toroidal displacement body relative to the fluid chamber.

Abstract: Small permanent magnets are affixed to the protruding portion of a rotor of a motor that is coupled to gears in a gear enclosure. The rod of a window covering is coupled to the gears such that when the motor is energized by a user command signal, the window covering moves. Small braking magnets are also affixed to the receptacle of the gear enclosure, such that when the motor is deenergized, the magnetic coupling between the magnets of the rotor and those of the gear enclosure brakes the rod from turning under the weight of the window covering.

Abstract: Disclosed are a combination type damper and a washing machine having the same. The combination type damper comprises: a cylinder provided with a receiving space having a certain depth at one side thereof; a rod relative-movably inserted into the receiving space of the cylinder; and a composite damping means for generating a damping force by an electromagnetic force when a displacement of a relative movement of the cylinder and the rod is less than a preset length, and for generating a frictional damping force when the displacement of the relative movement is more than the preset length. Transient state vibration and steady state vibration generated from a tub assembly during the entire processes for washing laundry are prevented from being transmitted to a cabinet, thereby minimizing vibration noise towards outside while using the washing machine.

Abstract: A rotary damper is disclosed. The rotary damper comprises a first and a second plurality of plates disposed within a housing. The first and second pluralities of plates are interleaved and are capable of moving relative to one another. A magnetorheological fluid contained within the housing resides in the interleave of the first and second plurality of plates. A magnetic flux generator drives a magnetic flux through the magnetorheological fluid in the interleave in a direction transverse to the orientation of the plates and is capable of varying the strength of the driven magnetic flux. The magnetic flux aligns the magnetic particles suspended in the magnetorheological fluid, increasing the shear strength of the magnetorheological fluid, which in turn resists motion between the first and second plurality of plates, acting as a damper.

Abstract: A suspension control system includes a plurality of damper assemblies, each damper assembly including an integrated velocity sensor and an integrated local controller with a drive unit connected to a damper coil of the damper assembly. A central controller may be connected for communication with the integrated local controller of each damper assembly. The local controller of each damper assembly normally controls the damper assembly independently of the central controller or other damper assemblies for carrying out at least one control function of the damper assembly. When provided, the central controller communicates with the local controller of each damper assembly for overriding local control functions. A related self-contained piston damper unit is also provided.

Abstract: The invention provides a magnetorheological piston and damper assembly. The piston includes a piston body including at least one bypass port and an annular gap formed therein. The bypass port is in fluid communication with the annular gap. The bypass port includes a longitudinal portion extending substantially parallel to a piston longitudinal axis, and a bend portion extending substantially away from the longitudinal axis. The annular gap is spaced apart from the longitudinal portion and extends substantially parallel to the piston longitudinal axis. During operation, fluid flows through the bypass port and annular gap. The damper assembly includes a rod and a housing including the fluid carried therein. The piston is slidably carried in the housing and operably attached to the rod.

Abstract: Brake assembly for cyclists' training device, provided with a support structure (7) on which there is rotatably mounted a shaft (10) having, keyed thereto, a roller (6) rotating in contact with the rear wheel of a bicycle. An end portion (12) of the shaft (10) is provided for this purpose with magnetic elements (13) able to exert a resistive torque and provided with a rotor (17) keyed onto the shaft (10) and carrying, fixed thereon, one or more permanent magnets (18) and a stator (19) mounted on the support structure (7) in the vicinity of the rotor (17). The stator (19) is composed of a disk of ferromagnetic material (20) and a shaped plate (21) of substantially conductive and non-magnetic material fixed to the ferromagnetic disk (20) on the side where the rotor (17) is located.

Abstract: The invention provides a magnetorheological damper assembly and piston. The assembly includes a housing with a fluid carried therein, a piston slidably carried in the housing, a rod and a valve both operably attached to the piston. The piston includes at least one passageway formed therein. The valve includes at least one bypass opening formed therein and at least one variable opening formed between a piston surface and the valve. The valve provides asymmetric fluid flow through the passageway. During operation, the variable opening selectively restricts fluid flow and the bypass opening maintains fluid flow through the passageway.

Abstract: A shock and vibration isolation system for mounting equipment to a base wall uses a semi-active damper in parallel with a spring arrangement to provide optimum isolation with respect to both shock and vibration. The system comprises a load plate configured for attachment of the equipment thereto and a base plate configured for attachment to the base wall. The base plate is substantially parallel to the load plate with a spring arrangement disposed intermediate the load plate and the base plate. The spring arrangement engages the load plate and the base plate to bias the load plate and the base plate in a separated relationship. The system also comprises a damping arrangement disposed intermediate the load plate and the base plate. The damping arrangement is adapted for providing a selectively variable reaction force to the load plate and the base plate responsive to a relative displacement of the load plate with respect to the base plate.

Abstract: A piston damper assembly includes a piston damper and a relative velocity sensor. The piston damper includes a damper body, a piston rod, and a dust tube which is attached to the piston rod. The relative velocity sensor incudes an axially extending first magnet supported by the dust tube, a flux collector, and a first sensor coil. The flux collector is supported by the dust tube, includes an axially-extending first prong in axially-extending contact with the first magnet, includes an axially-extending second prong, and includes a joining member connecting the first and second prongs. The first sensor coil surrounds the joining member and/or one of the first and second prongs. A piston-damper dust tube subassembly includes the dust tube and the relative velocity sensor.

Abstract: Magnetorheological devices, including damping devices, rotary devices, and haptic systems constructed with said devices are disclosed. The devices contain dry magnetically-responsive particles, or MR fluids containing the magnetically responsive particles. The magnetically soft particles characterized by a single process yield population of atomized particles having a cumulative 10%, 50% and 90% by volume, fraction within specified size, i.e., D10 of from 2 up to and including a D10 of 5 &mgr;m, a D50 8 &mgr;m up to and including a D50 of 15 &mgr;m, a D90 of 25 &mgr;m up to and including a D90 of 40 &mgr;m, and characterized by a least squares regression of log normal particles size against cumulative volume % fraction of greater than or equal to 0.77.

Abstract: There is provided a simplified loading device in which a permanent magnet is arranged between a moving element and a fixed element for holding the moving element, a magnetic fluid is disposed in a gap developed at some midpoint in a magnetic circuit in which the magnetic flux of the permanent magnet passes through the moving element, and a shearing force of the magnetic fluid produced by the magnetic flux of the permanent magnet is exerted on the moving element as a loading force.

Abstract: A spacecraft isolator including shape memory alloy components that are electronically heated to unlock the isolator. The isolator can be manually unlocked with an adjustment bolt.

Abstract: A device for braking a flow of molten metal (5) in a device for continuous or semi-continuous casting of metals in a mould (2) which is provided with opposite broad sides (4) and opposite short sides (3), said device comprising at least one magnet core (1), said at least one core facing one of the short sides (3) of the mould (2) for the purpose of generating a magnetic field (B) and an induced current (i) in a region of the molten metal (5) adjacent the short side (3). The core (1) is arranged in such a way that the magnet field (B) which is generated in said region generally has a direction perpendicular from the short side (3) of the mould (2) towards the centre of the latter.

Abstract: A vibration damping system (8) wherein the system (8) comprises a magnetism generating medium (12) and a magnetism energy dissipating medium (16) whereby, in use, vibration of the magnetism generating medium (12) generates a magnetic field, the magnetism generating medium (12) and the magnetism energy dissipating medium (16) being so disposed with respect to each other that the magnetic field is then dissipated by the magnetism energy dissipating medium (16) thereby damping the vibrations of the magnetism generating medium (12).

Abstract: A vehicular damper includes a cylinder, a piston rod in the cylinder having a hollow end defining an axial rod passage and a cylindrical piston affixed to the end of the rod dividing the cylinder into a compression chamber and a rebound chamber. A valve plate on the rod adjacent the piston has a plurality of soft channels extending from an outer end at the rebound chamber to an inner end at the axial rod passage and a solenoid actuated cylinder in the rod passage is movable to open and close the inner ends of the soft channels. A bi-directional working disc contacts with the soft channels' outer ends to provide damping in rebound and compression when the solenoid valve is open.

Abstract: A damper in which magnetic particles are difficult to sediment irrespective of the kind of a magnetic fluid is provided. A damper is constituted of a vessel in which the magnetic fluid is accommodated and a slider (piston). As the piston, one that is made of a laminated body of a paramagnetic substance and a non-magnetic substance is used. When thus constituted, the magnetic particles stick to the piston. Accordingly, whatever magnetic fluid is used, the particles do not sediment. The laminated body that is used as the piston has the non-magnetic substance at both ends thereof. When the laminated body is thus constituted, the magnetic particles sticks uniformly. When the laminated body has the magnetic substance at both ends, magnetic particles stick to both ends needle-like.

Abstract: A magnetorheological piston includes a magnetorheological-piston coil and a magnetorheological-piston core. The magnetorheological-piston coil has a longitudinal axis. In one expression, the magnetorheological-piston core includes at least two separate core pieces, wherein each of the core pieces is a powder-metal core piece, and wherein the coil is positioned to circumferentially surround at least a portion of at least one of the core pieces. In another expression, the magnetorheological-piston core includes separate upper core, center core, and lower core pieces. The center core piece is located longitudinally between the upper core and lower core pieces and has a circumferential surface positioned radially inward from the inner-diameter portion of the coil. The coil is longitudinally positioned between the upper core and lower core pieces. In one example, each of the upper core, center core, and lower core pieces is a powder-metal core piece.

Abstract: A friction damper a housing including a cavity formed therein; a first member disposed in said cavity and movable in said cavity; a second member disposed in said cavity; an intermediate member between the first and second members, the first member being in frictional engagement with the intermediate member; and at least one magnetic field generator mounted to magnetically couple the first and second members thereby maintaining the first member in frictional engagement with the intermediate member and wherein the first member is movable against the intermediate member to generate a damping force.

Abstract: A vibration damping system 8 wherein the system 8 comprises a magnetism generating medium 12 and a magnetism energy dissipating medium 16 whereby, in use, vibration of the magnetism generating medium 12 generates a magnetic field, the magnetism generating medium 12 and the magnetism energy dissipating medium 16 being so disposed with respect to each other that the magnetic field is then dissipated by the magnetism energy dissipating medium 16 thereby damping the vibrations of the magnetism generating medium 12.

Abstract: A magnetically actuated motion control device includes a housing defining a cavity and including a slot therethrough. A movable member is located within the cavity and is movable relative to the housing. A magnetic field generator located on either the housing or the movable member causes the housing to press against the movable member to develop a friction force. The flux caused by the magnetic field flows through the housing, the movable member and at least one pole located along the movable member. The at least one pole comprises a first portion having a first axial dimension and a second portion having a second axial dimension where the first axial dimension is greater than the second axial dimension and as a result the magnetic flux through the second portion of the at least one pole has a greater magnitude than the magnetic flux through the first portion of the pole.

Abstract: Performance of a vehicle damper utilizing a Magneto-Rheological (MR) fluid is enhanced through use of a piston having grooves in the walls of a magnetic flux path portion of a fluid flow passage through the piston. The grooves result in a focusing and intensification of the magnetic flux emanating from the corners of the grooves, to thereby intensify the magnetic flux impressed across the fluid flow passage and cause a greater degree of change in viscosity of the MR fluid flowing through the passage than is achievable in prior MR dampers having smooth-walled fluid flow passages.

Abstract: An adjustable vehicle suspension strut configured to be arranged between a wheel assembly and a body of a vehicle, the adjustable strut including a tube. A piston is slidably carried in the tube on a piston rod. A coil is carried on the piston adjacent a first flow passageway in the piston to produce a magnetic field thereacross and a control valve is carried on the piston controlling fluid flow through a second flow passageway in the piston. The control valve is positioned at the distal end of the rod upstream of the first flow passageway.

Abstract: A method and system for controlling an eddy current braking system in a motor vehicle is provided. The motor vehicle includes a prime mover linked to the eddy current braking system to provide torque thereto, and the eddy current braking system has a retarder assembly including at least a rotor and a stator. The method includes the steps of detecting a feedback current from the retarder assembly, detecting a rotor speed of the rotor, providing a signal indicative of a desired retarding torque, and determining a command current for the retarder as a function of the feedback current, rotor speed and desired retarding torque using a closed-loop sliding-mode control algorithm. The command current is provided to the retarder to control application of torque to the prime mover.

Abstract: A method and system for controlling an eddy current braking system in a motor vehicle is provided. The motor vehicle includes a prime mover linked to the eddy current braking system to provide torque thereto, and the eddy current braking system has a retarder assembly including at least a rotor and a stator. The method includes the steps of detecting a feedback current from the retarder assembly, detecting a rotor speed of the rotor, providing a signal indicative of a desired retarding torque, and determining a command current for the retarder as a function of the feedback current, rotor speed and desired retarding torque using a closed-loop sliding-mode control algorithm. The command current is provided to the retarder to control application of torque to the prime mover.

Abstract: A magnetorheological fluid (32) having controlled-shaped particles (56,68), such as rod, prism, tetrahedral, and other regularly shaped particles. The regularly shaped particles (56, 68) increase the field yield and responsive to particle interaction forces. The magnetorheological material has particular use for space applications such as vibration isolators, vibration dampeners, and latch mechanisms.

Abstract: An apparatus comprising a frame; a member movable relative to said frame; a damping device interconnected between the frame and the movable member; a controller for activating said damper to generate a damping condition at a predetermined member operating condition; and system for activating the damping device at a predetermined operating condition of the moving member during a loss of power to the apparatus. The damping device may comprise a field controllable damper that includes a volume of field controllable fluid, which may in turn comprise magnetorheological fluid for example. The rheology of the field controllable fluid is effected during the application of said field.

Abstract: The invention disclosed is a compact and lightweight hybrid pneumatic-magnetic isolator-actuator capable of large force, substantial stroke and bandwidth actuation with near frictionless operation and vibration isolation with very low break frequency. Pneumatic and magnetic forces are applied to a single carriage comprised primarily of a coaxially arranged air piston and coil. The carriage is driven relative to a frame or housing including an internally mounted cylindrical piston sleeve and magnetic actuator body. A combination of air bearings and air bearing piston construction provide for frictionless motion of the carriage relative to the frame. The pneumatic piston provides the actuation force for both static loads and low frequency dynamic loads. An integrally mounted sensor and control unit determine the pressure error resulting at the pneumatic piston.

Abstract: The object of the present invention is to provide a vibration damping apparatus having 6 degrees of freedom using a magnetic circuit. Vibration transfer can be isolated by a vibration damping mechanism to set the spring constant utilizing a relative displacement of a movable magnet 37 to a stationary magnet 27 in an axial direction, and an elastic force of a metal spring 50 substantially to be zero. The displacement is quickly restored to an original position by a rubber 24a and the metal spring 50 composing a device to restore the displacement due to vibration not only in an axial direction (Z axis direction) but also in a horizontal direction (X or Y axis direction), in a rotational direction around each axis, or in a twisting direction which is an overlapping direction of these directions and is damped as a vibration in an axial direction. Accordingly, a vibration having 6 degrees of freedom can be controlled with a simple structure.

Abstract: An eddy current brake or retarder device for bringing a vehicle to rest is disclosed. The device includes a stator mounted to a frame of the vehicle, a plurality of poles disposed along a perimeter of the stator, a plurality of coils each wound about each of the plurality of poles, wherein an adjacent pair of poles form an electromagnet when the coil is energized, and a rotor in communication with a transmission axle of the vehicle and located concentric with the stator. A relative rotation of the rotor with respect to the stator produces eddy currents between the poles of the stator and an outer surface of the rotor, causing the rotor to come to a rest.

Abstract: The invention comprises a retarder system for use with road vehicles. The retarder system discloses two improvements. The first is a system incorporating a self-excited electromagnetic and hydraulic retarder combination. The second is a retarder system incorporating the use of a PMG Gear ratio which permits use of a permanent magnet generator on a secondary shaft which is coupled by the gear ratio to a drive train.

Abstract: A magnetorheological fluid actuated damper. At least a first and a second cylinder with the first cylinder positioned axially within the second cylinder are provided. A gap is formed between the cylinders. The second cylinder is mounted to a stationary mount of the vehicle chassis and a control arm is mounted at an end of the first cylinder. The first cylinder is mounted on bearings to allow it to rotate relative to the chassis. The gap between the cylinders contains a magnetorheological fluid having an adjustable viscosity in reaction to the application of a magnetic field. A magnetic field is generated over the fluid in the gap.

Abstract: A suspension assembly for a motor vehicle includes a wheel assembly attached to the frame of a motor vehicle for movement in response to uneven roadway surfaces. A first inductive coil attached to the frame is mounted along an axis, and a second inductive coil is mounted co-axially with the first inductive coil and for movement with the wheel assembly. The inductive coils are movable relative to one another along the axis. An electromagnetic force generated by the inductive coils provides spring and dampening forces for the motor vehicle. Further, variation in the inductance between the coils is measurement to determine the relative position between the coils in order to monitor motor vehicle ride height.

Abstract: The piston for a magneto-rheological fluid system is manufactured from a piston skirt of a material having a high magnetic permeability and a piston plate which closes one end of the piston skirt having a low magnetic permeability and therefore must be made out of a material such as stainless steel. The piston is manufactured by placing the plate on one electrode and clamping another set of electrodes against the outer circumferential surface of the piston ring or skirt. The plate and ring are brought into contact with one another while applying a current through the piston ring and the piston plate, thereby heating interfering portions of the ring and plate and permitting the plate to be forced inside of the ring while at the same time allowing the softened or plastic portions of the ring and plate to intermingle with one another and thus form a solid state bond.

Abstract: An eddy current braking apparatus is disclosed. The apparatus includes a stator, a coil of wire, and a drum. The stator has a plurality of poles and is mountable to a frame of a vehicle. The coil of wire is wound about each of the plurality of poles and wherein adjacent coils are electrically connected to form an electromagnet. The drum is adapted to receive a wheel and tire assembly and wherein the drum is rotatably mounted to a vehicle axle, and wherein an eddy current is developed between the drum and the stator, from the relative motion of the drum with respect to the stator, thereby retarding rotation of the drum and wheel and tire assembly.

Abstract: A controllable brake includes a rotor supported on one shaft end. The rotor is housed within a chamber containing a field controllable material which is acted upon by a magnetic field generator to change the rheology of the material and thereby impede movement of the rotor. The shaft is supported by two bearings which, in combination with the housing define a second housing chamber adapted to enclose means for monitoring and/or controlling the brake and in this way, an integrated, compact controllable brake is provided.

Abstract: A system that includes a magnetically actuated motion control device comprising a housing defining a cavity and including a slot therethrough. A movable member is located within the cavity and is movable relative to the housing. A magnetic field generator located on either the housing or the movable member causes the housing to press against the movable member to develop a friction force.

Abstract: An improved control mechanism for use in a magnetically operated wheel mainly is made up of an outer cover, an inner housing, a pair of compression springs, two small supporting wheels, two linkage pieces, an externally connected pull cord control mount, a sensor, a signal transmitter mount and an internal or external transmission set. In adjustment, only a motor is activated to make a main transmission device, a secondary transmission device, a driven gear, a restraint unit and a driving wheel rotate in synchronism. Besides, when the driving wheel rotates, a lower gear and the linkage rack of the two pivotal linkage pieces equipped with a plurality of magnets and housed in a flywheel are in mesh engagement with each other to vary the distance between the magnets and the flywheel so as to make the adjustment of braking resistance of the flywheel in a stageless manner.

Abstract: A magneto-rheological (“MR”) damper having a damper body tube containing an MR fluid. A piston assembly is disposed in the damper body tube and forms an annular flow gap between the piston assembly and the damper body tube. The piston assembly has a piston core containing ferrous material and an electromagnetic coil mounted on the piston core for generating a magnetic field. The damper further includes a ferromagnetic member positioned outside of the damper body tube substantially adjacent the piston assembly for providing at least a part of a magnetic flux return path for the magnetic field.

Abstract: The invention comprises a retarder system for use with road vehicles. The retarder system can combine an electromagnetic retarder with up to four functions: 1) a brushless DC alternator; 2) a brushless DC starter; 3) an active damper that replaces the vehicle's flywheel and smooths out residual torque pulsations; and, 4) a transmission-synchronizing inertia brake; and, 5) a transient engine booster to offset the lag associated with turbo-charged engines. The device may be integrated within the engine or within the transmission, preferably using the vehicle heat exchanger for its cooling system.

Abstract: There are disclosed a vibration isolating apparatus and a vibration eliminating method imposed less restrictions on the positioning of components, such as active actuators, forming part of the vibration isolating apparatus. The vibration isolating apparatus can be implemented with a relatively simple controller (such as an analog circuit) and can limit the interference of control forces to a practically ignorable degree. The vibration isolating apparatus has a table for mounting thereon a device vulnerable to vibrations, a plurality of sensors 15-20 for detecting motions of the table and a plurality of active actuators 11-14 for controlling positions of the table.

Abstract: Brake assembly for cyclists' training device, provided with a support structure (7) on which there is rotatably mounted a shaft (10) having, keyed thereto, a roller (6) rotating in contact with the rear wheel of a bicycle which will thus be braked by the brake assembly (2) itself so as to simulate the resistance to forward movement experienced by a normal cyclist. An end portion (12) of the shaft (10) is provided for this purpose with magnetic means (13) able to exert a resistive torque. Said magnetic means are provided with a rotor (17) keyed onto the shaft (10) and carrying, fixed thereon, one or more permanent magnets (18) and a stator (19) mounted on the support structure (7) in the vicinity of the rotor (17). The stator (19) is composed of a disk of ferromagnetic material (20) and a shaped plate (21) of substantially conductive and non-magnetic material fixed to the ferromagnetic disk (20) on the side where the rotor (17) is located.

Abstract: The invention concerns a launch vehicle comprising a shroud (1a, 5a) supporting auxiliary propellers (2, 3) applying in operation excess flow of stresses to the shroud (1a, 5a), said device comprising means for coupling the payload (4) with the launch vehicle shroud. The invention is characterized in that the coupling means are designed to ensure a mechanical coupling between the payload (4) and the shroud along the direction of the launch vehicle longitudinal axis (X), and to cause them to be disengaged along radial and tangential directions. The invention is useful for neutralizing the effects on the payload of excess stresses applied on the launch vehicle shroud by the auxiliary propellers (2, 3).

Abstract: A device for controlling the driving movements of a tracked vehicle includes a control lever 2 which can pivot about at least one pin 3, and a magnet arrangement by which any manually established position of the control lever 2 can be magnetically fixed. The strength of the magnetic fixing force is selected so that the control lever can be manually moved to a new position while overcoming the magnetic fixing force, and then the control lever is again magnetically held at the new position.

Abstract: A vehicle steering system includes a steering wheel and a steering shaft coupled between the steering wheel and wheels of the vehicle. The shaft is operable for rotating when the steering wheel is turned to thereby turn the vehicle wheels. A vibration damping system for absorbing vibrations in the steering wheel and shaft includes a rotor coupled to the steering shaft to rotate with the shaft and a case surrounding the rotor and a clutch surface proximate the rotor. A magnetic circuit generates a magnetic flux in the rotor. The rotor is operable to engage the clutch surface and thereby vibrationally couple the steering shaft to the case to absorb vibrations in the shaft, and when a magnetic flux is generated therein, to disengage the clutch surface so that the steering shaft may more freely rotate.

Abstract: A vibration damping apparatus using a magnetic circuit which is easier and less expensive to manufacture than conventional apparatus is provided. The apparatus comprises a moving member 30 placed to move relatively away from and close to magnets 20 and 21 and made of a magnetic material which generates attraction force between the moving member 30 and the magnets 20 and 21, metal springs 40 and 41 as elastic members urging the moving member 30 in a direction in which the moving member 30 approaches the magnets 20 and 21, and rubbers 60 and 61 as cushioning members mounted on predetermined positions to prevent the moving member 30 from coming in contact with the magnets 20 and 21.