Magnetic Fluid Or Material (e.g., Powder) Patents (Class 188/267.2)
  • Patent number: 8141689
    Abstract: A magnetorheological (MR) piston ring includes an MR-piston-ring body disposable within a cylinder of an MR damper. The MR-piston-ring body has a radially inner surface defining a boundary of a longitudinally-extending MR passageway. The MR-piston-ring body includes a surface portion which is slidingly engagable with the cylinder and which has first and second longitudinal ends. The surface portion includes at least one surface groove each defining a secondary MR passageway and extending from the first to the second longitudinal end or each defining an MR cavity extending from one of the first and second longitudinal ends toward, but not to, the other of the first and second longitudinal ends. An MR damper including the MR piston ring is also described.
    Type: Grant
    Filed: September 5, 2008
    Date of Patent: March 27, 2012
    Assignee: BWI Company Limited S.A.
    Inventors: James Louis Lopez, Jr., Jaroslaw S Skarbek
  • Publication number: 20120031719
    Abstract: Disclosed is a self-powered and self-sensing MR damping device, comprising: an MR damper part having a damper piston assembly and a damper cylinder, the damper piston assembly being movable relative to the damper cylinder under an external excitation; a power generator configured to generate electrical power according to the relative movement between the damper piston and the cylinder assembly; and an electrical circuit configured to estimate said relative movement to output a damper driving current based on the estimated velocity, wherein the MR damper part is further configured to generate a damper force according to the damper driving current. An electrical circuit for the device is also provided.
    Type: Application
    Filed: October 1, 2010
    Publication date: February 9, 2012
    Applicant: THE CHINESE UNIVERSITY OF HONG KONG
    Inventors: Wei Hsin LIAO, Chao CHEN
  • Patent number: 8104591
    Abstract: A shock absorber having a valve controlling the flow rate of fluid between a compression chamber and a rebound chamber in a housing and separated by a piston. The valve has an orifice component and a blocker component, one of which has a permanent magnet, and the other of which has a magnetically permeable material. Upon the application of sufficient fluid pressure, the blocker component is forced away from the orifice component, despite the magnetic bias that tends to attract the two structures. Because the magnetic force decreases as the two components are spaced farther apart, the shock absorber has excellent performance characteristics. Alternatively, a mechanical spring urges the blocker closed, and magnetic attraction between the blocker and a spaced opener mitigates the increased force of the compressed spring tending to close the valve.
    Type: Grant
    Filed: August 10, 2006
    Date of Patent: January 31, 2012
    Assignee: Eko Sport, Inc.
    Inventor: Darek C. Barefoot
  • Patent number: 8100238
    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.
    Type: Grant
    Filed: July 15, 2008
    Date of Patent: January 24, 2012
    Assignee: MAGNA Powertrain AG & Co KG
    Inventor: Herbert Steinwender
  • Patent number: 8100235
    Abstract: A controllable hydraulic bearing for damping vibrations in a defined frequency band is proposed, which includes an elastomeric body (1), two chambers which are filled with a magneto-rheological fluid and connected with one another by at least one channel (2), with the chambers having at least partially flexible chamber walls, wherein the buckling spring rate of the chamber walls represents a measure for a pressure change due to the volume displacement between the chambers, and at least one electromagnet which generates a magnetic field in the region of the channel (2). According to the invention, the magnetic field in the region of the channel (2) is an inhomogeneous magnetic field.
    Type: Grant
    Filed: August 8, 2008
    Date of Patent: January 24, 2012
    Assignee: ZF Friedrichshafen AG
    Inventors: Stefan Loheide, Hubert Siemer, Burkhard Meyer, Josef Burwinkel
  • Publication number: 20120006635
    Abstract: A system and method of controlling engine vibration mounted within a vehicle including at least one hydraulic mount, each mount including a fluid chamber. A pair of accelerometers sense relative acceleration across the mount between the engine and the frame and generate a relative acceleration signal. A control unit is electrically connected to the accelerometers. The control unit is adapted to generate an electronic control signal in response to the relative acceleration signal. The control device is responsive to the electric control signal for controlling the damping force of the hydraulic mount. A control algorithm calibrates the control unit such that maximum vibration damping occurs at and around the engine resonance bounce frequency.
    Type: Application
    Filed: September 23, 2011
    Publication date: January 12, 2012
    Inventors: Prasad V. Gade, Sanjiv G. Tewani, Thomas A. Baudendistel
  • Patent number: 8091692
    Abstract: An impact absorber using an energy-absorbing, fluid-impregnated material consisting of a porous interconnected network of solid material forming edges and faces of cells, preferably an open-cell reticulated or partially closed-cell foam, or formed from fibers or other cellular solids. The matrix is impregnated with a field responsive fluid such as a magneto- or electro-rheological fluid, or with a shear-rate responsive fluid such as a dilatant (shear-thickening) fluid. The material is placed under compression during impact, and may be housed within a cylinder and compressed by a piston. The stiffness of the composite material consisting of a matrix filled with a field responsive fluid can be controlled by varying the field intensity and spatial gradients of the applied field to vary the rheological properties of the fluid.
    Type: Grant
    Filed: March 3, 2003
    Date of Patent: January 10, 2012
    Assignee: Massachusetts Institute of Technology
    Inventors: Suraj S. Deshmukh, Gareth H. McKinley
  • Patent number: 8078360
    Abstract: A control apparatus of a variable damping force damper comprises first and second low-pass filters for cutting off high frequency components of a target current of the damper, where the first and second low-pass filters have different response characteristics. The control apparatus further comprises a low-pass filter selection unit for selecting one of the first and second low-pass filters based on at least one of the dynamic state of the vehicle body and the road surface condition.
    Type: Grant
    Filed: August 7, 2008
    Date of Patent: December 13, 2011
    Assignee: Honda Motor Co., Ltd.
    Inventor: Shigenobu Sekiya
  • Patent number: 8056687
    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.
    Type: Grant
    Filed: August 3, 2007
    Date of Patent: November 15, 2011
    Assignee: GM Global Technology Operations LLC
    Inventors: Mark A. Golden, John C. Ulicny, Yang T. Cheng
  • Patent number: 8051961
    Abstract: In a magneto-rheological variable damper (6), the piston (16) comprises an inner yoke (32), an outer yoke (31) concentrically surrounding the inner yoke and held in position by pair of end plates (33, 34) made of non-magnetic material and disposed on either axial end surfaces of the piston. The piston may be circumferentially surrounded by a piston cover (30) that may be made of non-magnetic material and serves a slide member that engages the inner circumferential surface of a cylinder (12). Alternatively, the end plates may serve as the slide member. In either case, the durability of the damper can be improved by using a wear resistant material for the slide member. In particular, the outer yoke may be made of material such as Permendur which has a high saturation magnetic flux density but a poor mechanical property. Thereby, the range of the damping force can be expanded.
    Type: Grant
    Filed: September 25, 2008
    Date of Patent: November 8, 2011
    Assignee: Honda Motor Co., Ltd.
    Inventors: Yoshitomo Azekatsu, Hajime Kajiwara
  • Patent number: 8042659
    Abstract: A system for reducing vibrations in a rotating system uses a variable viscosity medium that is redistributed in a housing connected to the rotating system. Specifically, the medium is responsive to a control signal that is generated as a function of rotational speed of the rotational system. The control signal activates a triggering device that promotes a change in viscosity of the medium such that it is distributed within the housing in a manner that reduces vibratory loads.
    Type: Grant
    Filed: October 14, 2003
    Date of Patent: October 25, 2011
    Assignee: Sikorsky Aircraft Corporation
    Inventor: William Arthur Welsh
  • Patent number: 8046129
    Abstract: A system and method of controlling engine vibration mounted within a vehicle including at least one hydraulic mount, each mount including a fluid chamber. A pair of accelerometers sense relative acceleration across the mount between the engine and the frame and generate a relative acceleration signal. A control unit is electrically connected to the accelerometers. The control unit is adapted to generate an electronic control signal in response to the relative acceleration signal. The control device is responsive to the electric control signal for controlling the damping force of the hydraulic mount. A control algorithm calibrates the control unit such that maximum vibration damping occurs at and around the engine resonance bounce frequency.
    Type: Grant
    Filed: October 29, 2003
    Date of Patent: October 25, 2011
    Assignee: BWI Company Limited S.A.
    Inventors: Prasad V. Gade, Sanjiv G. Tewani, Thomas A. Baudendistel
  • Patent number: 8016087
    Abstract: In a fluid damper that autonomously changes a damping force in accordance with movement of a piston, the fluid damper having: a fluid 8 having magnetic properties; a piston 2 formed of a magnetic material; a cylinder 3 that encapsulates the fluid 8 having magnetic properties and accommodates the piston 2; a piston rod 4 that pierces the cylinder 3 to support the piston 2; a magnetic field generation device 6 provided outside the cylinder 3; a first yoke 5 arranged around the cylinder 3; and a second yoke 7 arranged around the piston rod 4 outside the cylinder 3, a magnetic circuit is partially formed.
    Type: Grant
    Filed: February 9, 2007
    Date of Patent: September 13, 2011
    Assignee: Central Research Institute of Electrical Power Industry
    Inventors: Takahiro Murakami, Hideo Araseki
  • Patent number: 8016092
    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.
    Type: Grant
    Filed: April 29, 2008
    Date of Patent: September 13, 2011
    Assignee: Honda Motor Co., Ltd.
    Inventor: Andrew Joseph McDaniel
  • Patent number: 7997393
    Abstract: A magnetorheological (MR) rod guide assembly includes a nonporous MR-rod-guide-assembly housing, annular first and second seals, and a non-annular, porous filter plug. The housing has a through bore. The first and second seals are positioned in the through bore, are adapted to sealingly contact an MR piston rod, and are longitudinally spaced apart defining an inter-seal portion of the through bore. The filter plug is positioned in the housing, has a longitudinal first end in fluid communication with the through bore longitudinally outside the inter-seal bore portion, and has a longitudinal second end in fluid communication with the through bore longitudinally within the inter-seal bore portion.
    Type: Grant
    Filed: February 20, 2008
    Date of Patent: August 16, 2011
    Assignee: BWI Company Limited S.A.
    Inventor: John A. Hart
  • Publication number: 20110148071
    Abstract: A movement damping apparatus has a flow path through which a magneto-rheological fluid is pressed. A device that generates a variable magnetic field has a core around which a coil is wound as well as pole surfaces in the flow path. The magnetic field acts on the magnetorheological fluid by way of the pole surfaces. The coil is arranged within the flow path along with the core, the axis of the coil extending perpendicular to the direction of flow of the magnetorheological fluid. The flow path has a jacket made of a magnetically conducting material.
    Type: Application
    Filed: August 21, 2009
    Publication date: June 23, 2011
    Applicant: INVENTUS ENGINEERING GMBH
    Inventors: Stefan Battlogg, Juergen Poesel, Gernot Elsensohn
  • Publication number: 20110140392
    Abstract: A movement damping apparatus has magnetorheological fluid that is pressed through a flow path forming a bottleneck in order to dampen a movement. The flow path is divided into at least two flow tracks by a partition that forms an additional friction surface.
    Type: Application
    Filed: August 21, 2009
    Publication date: June 16, 2011
    Applicant: INVENTUS ENGINEERING GMBH
    Inventors: Stefan Battlogg, Juergen Poesel, Gernot Elsensohn
  • Patent number: 7958979
    Abstract: In a variable damper using magneto-rheological fluid that comprises a cylinder (12) filled with the fluid, a piston (16) slidably received in the cylinder and including an inner yoke (32; 62; 126), an outer yoke (31; 64, 65; 140) and a coil (34; 130), a piston rod (13) having an inner end attached to the piston and an outer end extending out of the cylinder and a magnetic valve formed in a gap between the inner and outer yokes, at least one of the outer yoke and inner yoke consisting of at least two parts that are joined to each other in an axial direction. The two piece arrangement of the inner yoke or outer yoke allows the end plates to be omitted because the gap spacer can be installed without requiring end plates, and this contributes to a compact design and a favorable damping property. Also, the manufacturing and servicing of the damper can be simplified. When end plates (134) are used, the freedom in the positioning of the coil is increased.
    Type: Grant
    Filed: December 12, 2007
    Date of Patent: June 14, 2011
    Assignee: Honda Motor Co., Ltd.
    Inventors: Shigenobu Sekiya, Yoshitomo Azekatsu
  • Publication number: 20110127706
    Abstract: An apparatus of a damper (46) for a bicycle comprising a housing defining a chamber, and a piston, movable in the chamber along a first direction. The apparatus further comprises a controllable means to vary the resistance to movement of the piston in the chamber, a sensor (62), and a controller (58) including a timer. Said sensor measures at least one dynamic quantity and produces an output signal based thereon. Said output signal is received by the controller, and said controller controls said controllable means based on said dynamic quantity as a function of time to control the level of damping. The invention further provides means for manually adjusting the level of rebound damping.
    Type: Application
    Filed: July 16, 2009
    Publication date: June 2, 2011
    Applicant: THE UNIVERSITY OF SHEFFIELD
    Inventors: Neil David SIMS, David Craig BATTERBEE
  • Patent number: 7950508
    Abstract: The present invention relates to a piston valve assembly which is used in a continuous damping control damper using magneto-rheological fluid. The piston valve assembly is coupled with an end of the piston rod, and a stopper having a flat upper surface which is surface-contacted with an upper plate is disposed between a core assembly and the upper plate, thereby properly dispersing a force applied to the piston rod. According to the present invention, the reliability and stability in the coupling between the piston rod and the piston valve assembly can be increased, thereby stably controlling the damping force of the damper. Further, the slot is formed in the core of the piston valve assembly so as to reduce the damping force in the lower speed range, thereby considerably improving the driving comport of a vehicle.
    Type: Grant
    Filed: November 30, 2007
    Date of Patent: May 31, 2011
    Assignee: S & T Daewoo Co., Ltd.
    Inventors: Min-Ho Jin, Dong-Rak Lee, Tae-Ho Kang
  • Publication number: 20110114421
    Abstract: An elevator brake assembly includes a braking fluid for providing a braking force. A first magnet provides a first magnetic field that influences the braking fluid to provide the braking force. The second magnet selectively provides a second magnetic field that controls how the first magnetic field influences the braking fluid to control the braking force.
    Type: Application
    Filed: September 7, 2007
    Publication date: May 19, 2011
    Inventors: Zbigniew Piech, Wojciech Szelag
  • Patent number: 7942248
    Abstract: A damper device comprising a first mode having a first level of damping, a second mode having a second level of damping corresponding to a predetermined function, a sensor system having a first output corresponding to a normal position and a second output corresponding to an end stop approaching position, and a control system operable for receiving the first output and the second output and executing the first mode and the second mode. The damper device is operable in the first mode when the control system receives the first output and is operable in the second mode when the control system receives the second output.
    Type: Grant
    Filed: December 31, 2002
    Date of Patent: May 17, 2011
    Assignee: LORD Corporation
    Inventors: Kenneth A. St. Clair, Kenneth R. Boone, Douglas E. Ivers
  • Publication number: 20110100775
    Abstract: A magnetorheolgical (MR) damper includes a piston assembly having a primary channel disposed along a longitudinal axis and contained in a cylinder. MR fluid is also contained in the cylinder. The piston assembly having a primary channel, or primary channel MR piston assembly, includes a piston body having a first end axially spaced from a second end and defining a hole therethrough. The primary channel is defined in an outer body surface of the piston body from the hole at the second end to a coil groove in the outer body surface about the axis. A secondary channel is defined in the outer body surface from the coil groove towards the first end to improve MR damper force performance at low primary channel MR piston assembly velocities.
    Type: Application
    Filed: October 30, 2009
    Publication date: May 5, 2011
    Applicant: DELPHI TECHNOLOGIES, INC.
    Inventors: Robert T. Foister, Thomas W. Nehl, William C. Kruckemeyer, Oliver Raynauld
  • Patent number: 7930150
    Abstract: A method of designing a magnetorheological (MR) fluid energy absorbing damper is provided that uses hydromechanical analysis with lumped parameters to allow a determination as to whether a potential damper design will provide predetermined characteristics, such as a desired dynamic force range and maximum piston velocity, with a selected MR fluid and yield stress and preferably meeting predetermined geometric limitations.
    Type: Grant
    Filed: January 4, 2008
    Date of Patent: April 19, 2011
    Assignee: GM Global Technology Operations LLC
    Inventors: Alan L. Browne, Nancy L. Johnson, Norman M. Wereley, Young Tai Choi, Wei Hu, Min Mao
  • Publication number: 20110083929
    Abstract: A method and apparatus for a fluid damper comprising a first fluid-filled chamber, a second chamber filled with a fluid having variable flow characteristics and at least partially displaceable by the first fluid, and a gas chamber, the gas chamber compressible due to the displacement of the second chamber. In one embodiment, the fluid in the second chamber is a variable rheology fluid.
    Type: Application
    Filed: October 12, 2010
    Publication date: April 14, 2011
    Inventor: John Marking
  • Patent number: 7922202
    Abstract: An energy-absorbing apparatus for occupant protection in vehicles has a receptacle in which a magnetorheological fluid is present, which in the event of an impact is pressed through a flow zone. The apparatus further has a device generating a variable magnetic field and which has a core which is wound with a coil. The magnetic field acts on the magnetorheological fluid in order to regulate the flow properties. The coil together with the core is arranged in the flow zone. The axis of the coil lies perpendicularly to the direction of flow of the magnetorheological fluid, and the flow zone has a sheathing formed of a magnetically conductive material.
    Type: Grant
    Filed: August 24, 2009
    Date of Patent: April 12, 2011
    Assignee: Thyssenkrupp Presta AG
    Inventors: Stefan Battlogg, Gernot Elsensohn, Helmut Kirmsze, Jürgen Pösel
  • Publication number: 20110056780
    Abstract: The controllable suspension system includes a strut with a magnetorheological fluid damper. The magnetorheological fluid damper includes a longitudinal damper tubular housing having a longitudinally extending axis and an inner wall for containing magnetorheological fluid. The damper includes a piston head movable within the damper tubular housing along a longitudinal length the housing, with the damper piston head providing a first upper variable volume magnetorheological fluid chamber and a second lower variable volume magnetorheological fluid chamber, with a fluid flow gap between the upper and lower fluid chambers, the damper piston having a longitudinal piston rod for supporting the piston head within the housing, with the piston supported within the housing with a piston rod bearing assembly disposed between the housing and the rod, with the piston rod bearing assembly having a piston rod bearing seal interface.
    Type: Application
    Filed: November 15, 2010
    Publication date: March 10, 2011
    Inventors: KENNETH ALAN ST.CLAIR, William J. McMahon, Robert Marjoram, Mark R. Jolly, J. David Carlson, K. Andrew Kintz
  • Patent number: 7900754
    Abstract: The invention provides a rotating tub washer with an on-off binary damper system for damping a problematic movement between the washer frame and the rotating tub. The on-off binary damper system has a friction pad and a housing friction damper surface, with the friction pad in contact with said housing friction damper surface.
    Type: Grant
    Filed: March 24, 2005
    Date of Patent: March 8, 2011
    Assignee: Lord Corporation
    Inventor: J. David Carlson
  • Patent number: 7900755
    Abstract: An energy absorbing device is provided that includes a damper assembly having inner and outer concentric tubes and a piston movable within the inner tube. The damper assembly is configured to form bi-fold valve-type cavities to operatively connect an inner chamber of the inner tube with an outer chamber formed between the inner and outer tubes. A magnetorheological fluid fills the chambers and the bi-fold valve-type cavities. The magnetorheological fluid preferably contains coated magnetic particles at about 10 to 60 percent by volume. Electrical coils adjacent the bi-fold valves are selectively energizable to such that the energy absorbing device provides a tunable damping force, preferably over the entire range of velocities of the piston, especially in automotive applications.
    Type: Grant
    Filed: September 28, 2007
    Date of Patent: March 8, 2011
    Assignee: GM Global Technology Operations LLC
    Inventors: Alan L. Browne, John C. Ulicny, Chandra S. Namuduri, Nancy L. Johnson, Norman M. Wereley, Young Tai Choi, Wei Hu, Min Mao
  • Patent number: 7891474
    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.
    Type: Grant
    Filed: April 29, 2008
    Date of Patent: February 22, 2011
    Assignee: Honda Motor Co., Ltd.
    Inventor: Andrew Joseph McDaniel
  • Publication number: 20110031075
    Abstract: A damping device for a two-wheeled vehicle having a first and a second damper chamber which are coupled to one another through a flow connection. The flow connection includes at least one flow valve provided with a damping channel. A magneto-rheological fluid is provided in the damping channel of the flow valve wherein the flow valve includes at least one magnetic device such that the damping channel of the flow valve can be exposed to a magnetic field of the magnetic device. The flow valve further includes at least one spring device. The magnetic device of the flow valve is provided on a valve piston and the valve piston is received in a deflection chamber to resiliently deflect counter to a spring force of the spring device such that the magnetic field of the magnetic device effective in the damping channel depends on the resilient deflection of the valve piston.
    Type: Application
    Filed: July 20, 2010
    Publication date: February 10, 2011
    Inventors: Stefan Battlogg, Jürgen PÖSEL, Gernot ELSENSOHN, Martin WALHERT
  • Patent number: 7885740
    Abstract: Upon searching control parameter used to adjust damping force of a damper from a map in accordance with damper speed and target damping force decided based on moving condition of the vehicle, the map sets the control parameter, which are relatively higher than the actual damping force characteristics, as map data in the area where the damper speed is less than a predetermined value, the area where the noise has the great influence on the sensor outputs. Therefore, it can be prevented that the control parameter of the damping force is varied largely or varied in a short period by the influence of noise, and the driving stability control of the vehicle can be executed exactly and the noise caused by switching the damping force of the damper can be reduced.
    Type: Grant
    Filed: September 29, 2009
    Date of Patent: February 8, 2011
    Assignee: Honda Motor Co., Ltd.
    Inventors: Masaki Izawa, Takafumi Kato, Shigenobu Sekiya
  • Patent number: 7878312
    Abstract: An adaptive energy absorption system for a vehicle seat is disclosed, utilizing an adaptive energy absorber or variable profile energy absorber (VPEA) for mitigating occupant injury due to extreme vehicle movement (e.g., during a vehicle shock event), and/or for mitigating vibration experienced by an occupant of the vehicle seat during normal vehicle operating conditions. Various configurations of dual-goal energy absorption apparatuses using both VPEA and fixed load energy absorbers (FLEAs) that enable both shock mitigation and vibration isolation are disclosed. A semi-active control absorption system, comprising a VPEA and FPEA configured to work in series, is also disclosed.
    Type: Grant
    Filed: June 29, 2007
    Date of Patent: February 1, 2011
    Assignees: University of Maryland, Techno-Sciences, Inc.
    Inventors: Gregory J. Hiemenz, Wei Hu, Norman M. Wereley, Peter Che-Hung Chen
  • Publication number: 20110017556
    Abstract: A damping device for use with a rotatably-mounted steering shaft. The damping device comprises a magnetorheological material that can be embedded in an open-network carrier and is directly or indirectly in contact with the steering shaft, a coil arranged in effective proximity to the magnetorheological material, and a body indirectly in contact with the steering shaft through the magnetorheological material, which does not rotate with the steering shaft. A voltage can be applied the coil to activate the magnetorheological material, increasing a viscosity of the magnetorheological material to inhibit relative rotation of the steering shaft and the body.
    Type: Application
    Filed: September 28, 2010
    Publication date: January 27, 2011
    Inventors: Clay Maranville, Dieter Giese, John Ginder, Joe Schmidt
  • Publication number: 20110017555
    Abstract: A damping device for a two-wheeled vehicle having a first and a second damper chamber which are coupled to one another through a flow connection. The flow connection includes at least one flow valve provided with a damping channel. A magneto-rheological fluid is provided in the damping channel of the flow valve wherein the flow valve includes at least one magnetic device such that the damping channel of the flow valve can be exposed to a magnetic field of the magnetic device. The flow valve further includes at least one spring device. The magnetic device of the flow valve is provided on a valve piston and the valve piston is received in a deflection chamber to resiliently deflect counter to a spring force of the spring device such that the magnetic field of the magnetic device effective in the damping channel depends on the resilient deflection of the valve piston.
    Type: Application
    Filed: July 20, 2010
    Publication date: January 27, 2011
    Inventors: Stefan Battlogg, Jürgen Pösel, Gernot Elsensohn, Martin Walhert
  • Patent number: 7874407
    Abstract: A magnetorheological fluid damping system includes a hydraulic cylinder, a piston head, a piston rod, and a porous valve. The hydraulic cylinder is configured for disposing magnetorheological fluid therein. The piston head is disposed within the hydraulic cylinder and has first and second sides defining first and second chambers within the hydraulic cylinder. The piston head is configured to be in sliding engagement with the hydraulic cylinder. The piston rod is connected to the piston head. The porous valve includes a magnetorheological fluid pathway, has first and second fluid connections, and is configured to dampen the flow of the magnetorheological fluid between the first and second fluid connections in accordance with a magnetic field. The first fluid connection is fluidly connected to the first chamber and the second fluid connection is fluidly connected to the second chamber. The magnetorheological fluid pathway at least partially directs magnetorheological fluid flow through a porous media.
    Type: Grant
    Filed: June 15, 2007
    Date of Patent: January 25, 2011
    Assignees: University of Maryland, GM Research & Development
    Inventors: Norman M. Wereley, Wei Hu, Eugene Cook, Alan L. Browne
  • Publication number: 20100307877
    Abstract: Present invention relates to a device for reducing vibrations of a vibrating object as well as a method for reducing vibrations, wherein the perturbing vibrations are reduced drastically by induction of counter-forces. In general, vibrations of equal frequency (counter-vibration) as the perturbing vibration are generated. The force generated by the counter-vibration acts onto the vibrating object, whose amplitude of vibration is to be reduced. The phasing of the counter-vibration is antipodal to the vibration to be reduced, preferably the force of the generated counter-vibration is greater than the force being necessary for compensation of the perturbing vibration. The transfer of the force of the counter-vibration onto the vibrating object is affected by means of a magnetorheological or electrorheological material, whereby the absolute value of the transmitted force is adjusted by the magnitude of an applied magnetical or electric field.
    Type: Application
    Filed: March 2, 2009
    Publication date: December 9, 2010
    Applicant: Fraunhofer-Gesellschaft zur forderung der Angewandten Forschung e.V
    Inventors: Holger Bose, Thomas Gerlach, Johannes Ehrlich, Angelo Merlo, Ippolito Massimo
  • Publication number: 20100300819
    Abstract: A rotary vane magnetorheological energy absorber, which enables a longer stroke capability in a more compact configuration than conventional magnetorheological devices, is disclosed. This novel device design is attractive for applications where long stroking capability, high force dynamic range, device size, and device weight are important. The improved magnetorheological energy absorber comprises an internal or external flow valve and a hollow body enclosing fixed and rotary vanes as well as magnetorheological fluid. Fluid flow in the valve is restricted as a solenoid is activated, thus adjusting the capability of the device to react torque. Various flow valve configurations are disclosed, as well as various motion translation mechanisms for translating linear motion to rotary motion for use of the rotary vane magnetorheological energy absorber.
    Type: Application
    Filed: June 14, 2010
    Publication date: December 2, 2010
    Inventors: Gregory J. Hiemenz, Wei Hu, Grum Ngatu, Norman Mark Wereley
  • Patent number: 7828129
    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.
    Type: Grant
    Filed: May 17, 2005
    Date of Patent: November 9, 2010
    Assignee: MAGNA Drivetrain AG & Co KG
    Inventor: Herbert Steinwender
  • Patent number: 7828126
    Abstract: A magnetorheological (MR) piston assembly (10) includes an MR piston (12) and a rod (14). The MR piston (12) includes a central longitudinal axis (16), first and second longitudinal ends (18 and 20), an MR passageway (22), a main electric coil (24), and a valve (26). The MR passageway (22) extends from the first longitudinal end (18) to the second longitudinal end (20). The main electric coil (24) is disposed to magnetically energize the MR passageway (22). The valve (26) is operatively connected to the MR passageway (22). The valve (26) has a first state when electrically activated which is less restrictive of the MR passageway (22) and has a second state when not electrically activated which is more restrictive of the MR passageway (22). The rod (14) is attached to the MR piston (12). A more detailed MR piston (12) and an MR damper system (60) are also described.
    Type: Grant
    Filed: September 13, 2007
    Date of Patent: November 9, 2010
    Assignee: BWI Company Limited S.A.
    Inventor: Saiman Lun
  • Publication number: 20100270773
    Abstract: A saddle riding type vehicle includes a vehicle body frame, a head pipe, a steering shaft, and a steering damper. The head pipe is attached to the front end of the vehicle body frame. The steering shaft is inserted rotatably in the head pipe. The steering damper includes an electromagnet, a magnetic member, and a magnetic fluid. The electromagnet is provided around the steering shaft and has a first surface. The magnetic member is provided around the steering shaft and has a second surface opposed to the first surface. The magnetic fluid is stored in a gap formed between the first and second surfaces. One of the electromagnet and the magnetic member is attached to the steering shaft and the other is attached to the head pipe.
    Type: Application
    Filed: April 22, 2010
    Publication date: October 28, 2010
    Applicant: YAMAHA HATSUDOKI KABUSHIKI KAISHA
    Inventors: Shidehiko MIYASHIRO, Nobuo HARA, Naoyuki HOSONO, Yasufumi TAKAGI, Takayuki SUZUKI
  • Publication number: 20100263971
    Abstract: Disclosed is a damper for continuously variably adjusting a damping force that includes: a cylinder; a piston rod that is inserted into the cylinder and moves back and forth; a piston valve that is coupled to a bottom portion of the piston rod and moves back and forth in the cylinder according to the movement of the piston rod; a MR fluid that fills the cylinder and moves between a tension space over the piston valve and a compression space below the piston valve; and a volume compensation means that is located in the cylinder and compensates for a volume change of an inner space of the cylinder due to the movement of the piston rod, the volume compensation means including: a floating plunger that is configured to be below the piston valve and capable of moving up and down; a coil spring that is coupled to a bottom surface of the floating plunger and supports the floating plunger; and a support cup that is fixed onto the cylinder, coupled to a bottom portion of the coil spring to support the coil spring, and
    Type: Application
    Filed: April 9, 2010
    Publication date: October 21, 2010
    Inventors: Dong-Rak LEE, Min-Ho Chin
  • Publication number: 20100231069
    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.
    Type: Application
    Filed: March 11, 2010
    Publication date: September 16, 2010
    Applicant: THE CHINESE UNIVERSITY OF HONG KONG
    Inventors: Wei Hsin LIAO, Hongtao Guo
  • Patent number: 7775333
    Abstract: An magnetorheological damper useful in structural vibration control has a damper body and a moveable portion relative to the damper body. The damper includes an magnetorheological material contained within the damper body for resisting movement of the moveable portion. Rheology changes can be generated in the magnetorheological material owing to changes in a magnetic field, to which the magnetorheological material is exposed. The damper further includes at least a sensor embedded in the damper for monitoring an external force exerted on the damper, and for generating a signal to control the magnetic field and hence the resulting yield force and rheological damping of the damper in response to a variance in the external force.
    Type: Grant
    Filed: June 6, 2007
    Date of Patent: August 17, 2010
    Assignee: The Hong Kong Polytechnic University
    Inventors: Siu Wing Or, Yiqing Ni, Yuanfeng Duan
  • Publication number: 20100193304
    Abstract: The present invention relates to a damping device having a first control element with a first surface (O1) and a second control element with a second surface (O2), the two control elements being moveable relative to each other with their two surfaces, a spatial region (intermediate space Z) which is filled at least partially with a magnetorheological and/or electrorheological material (M) and is disposed between the first and the second surface, and a field producer (4) with which a magnetic and/or electrical field can be produced in at least a partial region of the material-filled part of the intermediate space, and also a housing (1) which has two chambers (K1, K2) and in which a piston unit (2) which is moveable relative to the housing and a closing unit (3) which is moveable relative to the piston unit are disposed, the piston unit and the closing unit forming a throughflow opening (D) connecting the two chambers, through which a fluid (F) can be displaced between the two chambers by means of a relative m
    Type: Application
    Filed: April 11, 2008
    Publication date: August 5, 2010
    Applicant: Fraunhofer-Gesellschaft zur Forderung der angewandten Forschung e.v.
    Inventors: Holger Böse, Thomas Gerlach, Jörn Probst
  • Patent number: 7753180
    Abstract: A magnetorheological (MR) piston includes an MR piston core, an MR piston end plate, a shim disc, and a flexible orifice disc. The end plate covers an end of the core to define a chamber and has a through passageway aligned with an MR-piston-core bypass passageway at the chamber. The shim disc and the orifice disc are positioned in the chamber. The orifice disc includes an orifice aligned with the bypass passageway at the chamber and includes an additional orifice. Under fluid pressure in a first direction the orifice disc lies substantially flat against one of the end and the MR piston end plate. Under fluid pressure in an opposite second direction the orifice disc is deflected by the presence of the shim disc to lift the additional orifice from the one of the end and the MR piston end plate.
    Type: Grant
    Filed: June 20, 2007
    Date of Patent: July 13, 2010
    Inventor: Saiman Lun
  • Publication number: 20100152979
    Abstract: A machine employing controllable mounts and a method for controlling such mounts based on machine operation are disclosed. The controllable mount may include a housing, a pin, rheological fluid within the housing and coils provided proximate to the rheological fluid. As current is applied to the coils, the apparent viscosity of the rheological fluid is increased, and in so doing so are the damping and stiffness properties of the controllable mount. With certain machine operations such as fine grading, plowing and loading, this may be helpful to the operator to more quickly or effectively perform the given task. With other operations such as roading or working on a flat surface, the feedback afforded by the mounts is not as important as operator comfort, in which case the current applied to the coils can be lowered and thus the mount can be made more relaxed.
    Type: Application
    Filed: December 14, 2009
    Publication date: June 17, 2010
    Applicant: CATERPILLAR, INC.
    Inventors: Steven D. Jones, Ronald B. Warnat, Brett D. Ellen, Nathan S. Pauli, Michael S. Contratto
  • Publication number: 20100147640
    Abstract: A machine includes a frame and an operator cab supported by the frame. One or more passive mounts and one or more controllable mounts operatively connect the operator cab to the frame. The one or more controllable mounts include a housing, a pin mounted within the housing, a rheological fluid within the housing, and coils positioned relative to the housing to generate a field through the rheological fluid. An electronic control unit operatively associated with the coils and adapted to change a level of current applied to the coils to adjust an apparent viscosity of the rheological fluid to actively change the damping characteristics of the one or more controllable mounts.
    Type: Application
    Filed: December 14, 2009
    Publication date: June 17, 2010
    Applicant: Caterpillar Inc.
    Inventors: Steven D. Jones, Brett D. Ellen, Ronald B. Warnat, Kevin D. Ehrenhardt
  • Publication number: 20100152980
    Abstract: A machine employing controllable mounts and a method for controlling such mounts based on machine location are disclosed. The controllable mount may include a housing, a pin, rheological fluid within the housing and coils provided proximate to the rheological fluid. As current is applied to the coils, the apparent viscosity of the rheological fluid is increased, and in so doing so is the stiffness of the controllable mount. Depending on machine location, however, the operator may want differing levels of stiffness in one or more of the controllable mounts. For example, when roading on rocky terrain, the operator may want relatively loose mounts so as to absorb the large vibration inputs and make for a more comfortable ride.
    Type: Application
    Filed: December 14, 2009
    Publication date: June 17, 2010
    Applicant: CATERPILLAR, INC.
    Inventors: Steven D. Jones, Ronald B. Warnat, Brett D. Ellen
  • Publication number: 20100116607
    Abstract: A dual seal rod guide assembly with low friction disc for use in a magneto-rheological (MR) strut is described. The dual seals separate the functions of abrasion resistance and temperature performance, with the primary seal formed of a material resistant to high temperatures and the buffer seal formed of a material resistant to the ferroelectric microparticles in the MR fluid. The porous rod guide, in conjunction with the buffer seal, allow only the MR carrier fluid to reach the bearing and primary seal. The MR carrier fluid provides internal lubrication of the bearing and primary seal. The retainer holds the assembly together and engages the rod guide flexible assembly to the housing with a low-friction disc therebetween. The disc reduces surface friction during radial movement of the rod guide.
    Type: Application
    Filed: November 7, 2008
    Publication date: May 13, 2010
    Inventor: Saiman Lun