Magnetic Fluid Or Material (e.g., Powder) Patents (Class 188/267.2)
  • Patent number: 7703717
    Abstract: A transport vehicle wheel assembly comprising a set of rotating components and a set of static components wherein an applied electrical current applied to conductive material incorporated into at least one components structural matrix of one set of components gives rise to primary magnetic fields which interact with reactive magnetic fields associated with material incorporated into at least one components structural matrix of another set of components and gives rise to rotational forces which act on the rotating components of said transport vehicle wheel assembly to induce controlled forward rotation of a wheel and having regenerative braking and reverse drive ability thus allowing controlled retardation assistance.
    Type: Grant
    Filed: August 12, 2009
    Date of Patent: April 27, 2010
    Inventor: Rod F. Soderberg
  • Publication number: 20100096818
    Abstract: A magneto-rheological fluid damper includes a damper body having a reservoir for a magneto-rheological fluid, a piston rod, a piston rod guide disposed within the damper body, where the piston rod guide has a passage therein for receiving the piston rod. The magneto-rheological fluid damper further includes at least a first piston rod seal and at least a second piston rod seal arranged to seal between the piston rod guide and the piston rod. The magneto-rheological fluid damper further includes a fluid chamber defined between the piston rod guide and the piston rod, the fluid chamber being in communication with the reservoir. The magneto-rheological fluid damper further includes a piston rod guide filter arranged in a communication path between the fluid chamber and the reservoir to filter particulates out of the magneto-rheological fluid entering the fluid chamber. The magneto-rheological fluid damper further includes an accumulator arranged between the piston rod guide and the damper body.
    Type: Application
    Filed: November 2, 2009
    Publication date: April 22, 2010
    Inventors: ROBERT H. MARJORAM, Stephen F. Hildebrand, Douglas E. Ivers, Gregory Ericksen, William J. McMahon, Kenneth A. St. Clair
  • Publication number: 20100089711
    Abstract: A magneto-rheological damping device comprises a piston and a case element, both capable of acting to carry a magnetic flux. A passage exists between the piston and the case element, and an amount of MR fluid is positioned between the piston and the case element to flow within the passage. A first magnetic flux generator and a second magnetic flux generator cooperate to generate a net flux that is disposed to act upon the MR fluid in the passage to affect the flow of fluid in the passage. One of the flux generators comprises a permanent magnet to generate a bias flux between the piston and the case element, and the other flux generator comprises a means for providing a controllable magnetic flux between the piston and the case element.
    Type: Application
    Filed: October 15, 2008
    Publication date: April 15, 2010
    Inventors: Thomas Wolfgang Nehl, Alexander A. Alexandridis
  • Patent number: 7691154
    Abstract: The invention in some embodiments relates to systems and methods of controlling pressure within a prosthetic knee. The knee in one embodiment comprises a flexible diaphragm that substantially prevents or mitigates undesirable pressure build-up in a sealed chamber of the knee. The knee in another embodiment comprises a compressible gas in the chamber that substantially prevents or mitigates undesirable pressure build-up in the chamber.
    Type: Grant
    Filed: May 6, 2005
    Date of Patent: April 6, 2010
    Assignee: Össur hf
    Inventors: Sigurdur Asgeir Asgeirsson, Charles R. Bisbee, III, Henry H. Hsu
  • Patent number: 7686143
    Abstract: A controllable magnetorheological (MR) damper having first, second and third portions is disclosed. The first and second portions have a translational degree of freedom therebetween, and the third portion has a rotational degree of freedom with respect to the first and second portions. The first and third portions are coupled via a translation-to-rotation converter, and the second and third portions are coupled via a magnetorheological (MR) fluid. A bearing is disposed between the first and second portions for supporting a side load therebetween, a magnetic field generator is in field communication with the magnetorheological fluid, and a signal path is in signal communication with the magnetic field generator.
    Type: Grant
    Filed: October 11, 2007
    Date of Patent: March 30, 2010
    Assignee: GM Global Technology Operations, Inc.
    Inventor: Chandra S. Namuduri
  • Patent number: 7677370
    Abstract: An energy absorbing device, particularly for single-use occupant protection in vehicles on the action of an external force, has a free-flowing medium which is forced through a constriction by a mobile pressure element on the action of an external force. A pull device or tension device pulls on the pressure element on the action of the external force.
    Type: Grant
    Filed: June 12, 2008
    Date of Patent: March 16, 2010
    Assignee: Inventus Engineering GmbH
    Inventors: Stefan Battlogg, Jürgen Pösel
  • Patent number: 7669700
    Abstract: An elastomer bearing with hydraulic damping is disclosed which includes a housing (1, 2), a connecting element (3), an elastomer body (4) which couples the housing (1, 2) and the connecting element (3) with one another for damping oscillations, two chambers (5, 6) filled with a magneto-rheological fluid, at least one flow channel (8) connecting the chambers (5, 6) with one another for fluid conduction, as well as an actuator (11) associated with the flow channel and attached on the outside of the housing (1, 2) for generating a magnetic field. According to the invention, a field return element (10) with interacts with the actuator is arranged on or in the flow channel (8).
    Type: Grant
    Filed: April 4, 2007
    Date of Patent: March 2, 2010
    Assignee: ZF Friedrichshafen AG
    Inventors: Stefan Loheide, Hubert Siemer, Burkhard Meyer
  • Publication number: 20100045010
    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: Application
    Filed: August 24, 2009
    Publication date: February 25, 2010
    Applicant: THYSSENKRUPP PRESTA AG
    Inventors: Stefan Battlogg, Gernot Elsensohn, Helmut Kirmsze, Jürgen Pösel
  • Publication number: 20100032254
    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.
    Type: Application
    Filed: October 13, 2009
    Publication date: February 11, 2010
    Inventors: Eric N. Anderfaas, Dean Banks
  • Patent number: 7637360
    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.
    Type: Grant
    Filed: March 25, 2004
    Date of Patent: December 29, 2009
    Assignee: Lord Corporation
    Inventors: J. David Carlson, Richard Wilder
  • Patent number: 7628254
    Abstract: A damper containing magneto-rheological (“MR”) fluid and a plunger lies between and is mechanically coupled both to a fixture and a vibration source. The plunger has a head immersed in the MR fluid. Annular magnets circumscribe the damper and produce a magnetic field surrounding the damper. A tubular shielding sleeve composed of magnetically impermeable material surrounds a portion of the damper. The sleeve is mechanically coupled both to the fixture and the vibration source by springs, and can translate relative to the damper to affect the strength of the magnetic field acting on the MR fluid surrounding the plunger head. The sleeve oscillates responsive to vibration of the vibration source and controls the viscosity of the MR fluid surrounding the plunger head in proportion to the amplitude of the sleeve's oscillation. The resonant frequency of the sleeve is adjusted to approximate the fundamental resonance of the fixture.
    Type: Grant
    Filed: September 19, 2008
    Date of Patent: December 8, 2009
    Assignee: The United States of America as represented by the Secretary of the Air Force
    Inventors: Benjamin K. Henderson, Steven F. Griffin, Joel D. Gussy, Steven A. Lane, Elizabeth L. C. Jensen, Richard K. Davies, Jennifer A. Gruits, Paul W. Alexander, David M. Stevens, Ryan D. Majkrzak
  • Publication number: 20090294231
    Abstract: Please replace the Abstract with the following amended Abstract: A magneto-rheological fluid valve includes a magnetic field generator having at least one electromagnetic coil and at least one magnetic pole having a pole length Lm. The magneto-rheological fluid valve further includes at least one flow channel adjacent to the magnetic field generator. The at least one flow channel has a gap width g, wherein the ratio Lm/g is greater than or equal to 15.
    Type: Application
    Filed: June 2, 2009
    Publication date: December 3, 2009
    Applicant: LORD CORPORATION
    Inventors: J. David Carlson, Mark R. Jolly, Douglas E. Ivers
  • Patent number: 7624850
    Abstract: A damper assembly is provided including a linear to rotary motion conversion mechanism having an outer tube member. An inner tube member is reciprocally movable and at least partially disposed within the outer tube member. The inner tube member is adapted for linear translation in a first and a second direction. A rotatable shaft is disposed within the inner tube member. The translation of the inner tube member produces a rotation of the shaft. Also included within the damper assembly is a damping mechanism having a rotor fixed to the shaft. A coil is configured to generate an electromagnetic field in response to an applied current. A magneto-rheological fluid is in contact with the rotor, and has a variable viscosity in the presence of the electromagnetic field that, in turn, provides variable resistance to rotation of the rotor and translation of the inner tube member within the outer tube member.
    Type: Grant
    Filed: May 25, 2006
    Date of Patent: December 1, 2009
    Assignee: GM Global Technology Operations, Inc.
    Inventors: Chandra S. Namuduri, David S. Rule, Kenneth J. Shoemaker
  • Publication number: 20090277733
    Abstract: Presented is a piston-cylinder unit that includes a closed first end, a cylinder, a sealing device, and a piston installed in the cylinder with freedom to slide back and forth. The piston divides the cylinder into a first space at the closed end and a second space at the end opposite the closed end. The piston-cylinder unit further includes a piston rod attached to one side of the piston. The piston rod projects through the second space and is guided out of the cylinder concentrically with the longitudinal center axis of the cylinder at the second end, opposite the first end, in a sealed manner through the sealing device. The piston-cylinder unit further includes a ferrofluid, and at least one magnetic element that has a magnetic field, which cooperates with the ferrofluid present in the cylinder.
    Type: Application
    Filed: May 19, 2008
    Publication date: November 12, 2009
    Applicant: Stabilus GmbH
    Inventor: Frank DOFFING
  • Patent number: 7617032
    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: March 29, 2006
    Date of Patent: November 10, 2009
    Assignee: Honda Motor Co. Ltd.
    Inventors: Masaki Izawa, Takafumi Kato, Shigenobu Sekiya
  • Patent number: 7600616
    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.
    Type: Grant
    Filed: June 22, 2007
    Date of Patent: October 13, 2009
    Assignee: MillenWorks
    Inventors: Eric N. Anderfaas, Dean Banks
  • Publication number: 20090242340
    Abstract: A damping arrangement comprises a drive member arranged to be driven for angular movement relative to a housing by a motor, and a damping device independent of the motor and operable to damp oscillating motion of the drive member relative to the housing.
    Type: Application
    Filed: March 31, 2009
    Publication date: October 1, 2009
    Applicant: Goodrich Actuation Systems Limited
    Inventors: Kevin Richard Hadley, David John Connors
  • Patent number: 7588131
    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.
    Type: Grant
    Filed: April 29, 2005
    Date of Patent: September 15, 2009
    Assignee: Magna Drivetrain AG & Co KG
    Inventor: Herbert Steinwender
  • Publication number: 20090205913
    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: Application
    Filed: February 20, 2008
    Publication date: August 20, 2009
    Inventor: John A. Hart
  • Publication number: 20090188763
    Abstract: A magnetorheological (MR) fluid-based device including an MR piston assembly. The MR piston assembly includes a ferromagnetic MR piston core and an electric coil. The MR piston core has a central longitudinal axis and has an outer circumferential surface substantially coaxially aligned with the central longitudinal axis. The electric coil is positioned in the MR piston core and is substantially coaxially aligned with the central longitudinal axis. A portion, or at least a portion, of the electric coil is buried in the MR piston core under the outer circumferential surface.
    Type: Application
    Filed: January 29, 2008
    Publication date: July 30, 2009
    Inventors: Thomas Wolfgang Nehl, Alexander A. Alexandridis, Robert T. Foister, William C. Kruckemeyer, Fang Deng
  • Publication number: 20090133976
    Abstract: The present invention discloses a magnetorheological force transmission device which comprises at least two solid body parts 1a, 1b adapted to be moved in a substantially translational manner against each other, and an MRF gap 2, which is at least partially fillable and/or filled with a magnetorheological material 2MRF, the MRF gap 2 being arranged at least partially inside one of or both of the two parts and/or being arranged at least partially in-between the two parts, and which is characterized in that the magnetic circuit system of the magnetorheological force transmission device being designed and/or disposed to generate a magnetic flux within at least part of the MRF gap comprises at least one electromagnet 3, at least one permanent magnet 4 and at least one magnetic-field-balancing insert 5, 5a, 5b and/or magnetic isolator 7, 7a, 7b.
    Type: Application
    Filed: November 24, 2008
    Publication date: May 28, 2009
    Applicant: Fraunhofer-Gesellschaft Zur Forderung Der Angewandten Forschung E.V.
    Inventors: Holger Bose, Johannes Ehrlich, Patrick Meneroud, Gregory Magnac
  • Publication number: 20090107779
    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: Application
    Filed: September 25, 2008
    Publication date: April 30, 2009
    Applicant: Honda Motor Co., Ltd.
    Inventors: Yoshitomo Azekatsu, Hajime Kajiwara
  • Publication number: 20090090586
    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: Application
    Filed: September 5, 2008
    Publication date: April 9, 2009
    Inventors: James Louis Lopez, JR., Jaroslaw S. Skarbek
  • Publication number: 20090084646
    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: Application
    Filed: September 28, 2007
    Publication date: April 2, 2009
    Applicants: GM GLOBAL TECHNOLOGY OPERATIONS, INC., UNIVERSITY OF MARYLAND
    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: 7510061
    Abstract: An MR-fluid (magnetorheological-fluid) hydraulic mount includes a hydraulic-mount partition plate assembly and an electric coil. The partition plate assembly has a longitudinal axis, has first and second sides, and has an MR-fluid through orifice extending substantially parallel to the longitudinal axis from the first side to the second side. The partition plate assembly is devoid of any non-MR-hydraulic-fluid orifice. The electric coil is substantially coaxially aligned with the longitudinal axis and is adapted to magnetically influence the MR-fluid through orifice. The MR-fluid through orifice is positioned radially outward of the electric coil.
    Type: Grant
    Filed: December 27, 2005
    Date of Patent: March 31, 2009
    Assignee: Delphi Technologies, Inc.
    Inventors: Mark O. Bodie, Mark W. Long
  • Publication number: 20090071773
    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: Application
    Filed: September 13, 2007
    Publication date: March 19, 2009
    Inventor: Saiman Lun
  • Publication number: 20090071774
    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: Application
    Filed: November 30, 2007
    Publication date: March 19, 2009
    Applicant: S & T DAEWOO CO.,LTD
    Inventors: Min-Ho JIN, Dong-Rak LEE, Tae-Ho KANG
  • Publication number: 20090057078
    Abstract: A magneto rheological (MR) fluid damper system for use in a vehicle suspension system can include a twisted pair of conductors integrated into a hollow piston rod of the MR damper. The twisted pair of conductors provide a supply path for current to reach the actuating coil of the MR damper while also providing the current return path to an electric source. The twisted pair of conductors facilitates a reduction in capacitance in the operating circuit, and thus minimizes electromagnetic interference affecting other electrical systems in the vehicle.
    Type: Application
    Filed: August 31, 2007
    Publication date: March 5, 2009
    Inventors: Nate Ellis, Richard Owens, Lars David Moravy
  • Publication number: 20090050425
    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: Application
    Filed: February 9, 2007
    Publication date: February 26, 2009
    Inventors: Takahiro Murakami, Hideo Araseki
  • Patent number: 7493995
    Abstract: A shock absorber include a cylinder, a piston rod coupled to the cylinder, and a piston coupled to the piston rod. The piston rod is magnetically encoded so that it includes a plurality of magnetic phase shifts. The phase shifts allow the position of the piston rod relative to the cylinder to be determined so that it can function as a displacement sensor.
    Type: Grant
    Filed: July 14, 2005
    Date of Patent: February 24, 2009
    Assignee: Tenneco Automotive Operating Company, Inc.
    Inventors: Geert Sas, Mario Maes, Xavier Lauwerys, Pol Mermans, David Chiaradia
  • Publication number: 20080314705
    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: Application
    Filed: June 20, 2007
    Publication date: December 25, 2008
    Inventor: Saiman Lun
  • Publication number: 20080314706
    Abstract: One expression of an embodiment of the invention is for a damper including a damper cylinder and a damper gas cup assembly. The damper gas cup assembly is disposed in, and is slidingly engagable with, the damper cylinder and includes a gas-and-liquid-impermeable damper gas cup and a liquid-permeable member. The damper gas cup has a central longitudinal axis and has an outwardly-facing first circumferential surface with a fully-circumferential first surface groove. The first surface groove is adapted to receive a first seal. The member is disposed outside, and is attached to, the damper gas cup and has an outwardly-facing second circumferential surface with a fully-circumferential second surface groove. The second surface groove is adapted to receive a second seal. Another expression of an embodiment of the invention is for the damper gas cup assembly without mention of the damper cylinder.
    Type: Application
    Filed: April 24, 2008
    Publication date: December 25, 2008
    Inventor: Saiman Lun
  • Patent number: 7445094
    Abstract: A fixture is isolated from the transmission of vibration emanating from a vibration source by a damper containing magneto-rheological (“MR”) fluid and a plunger mechanically coupling the damper and the fixture. The isolation apparatus is mechanically coupled to the vibration source. The viscosity of the MR fluid contained in the damper is controlled by a magnetic field produced by the vibration of an isolation system responsive to the vibration of the vibration source. The resonant frequency of the isolation system is adjusted to approximate that of the fixture.
    Type: Grant
    Filed: October 11, 2005
    Date of Patent: November 4, 2008
    Assignee: The United States of America as represented by the Secretary of the Air Force
    Inventors: Benjamin K. Henderson, Steven F. Griffin, Joel D. Gussy, Steven A. Lane, Elizabeth L. C. Jensen, Richard K. Davies, Jennifer A. Gruits, Paul W. Alexander, David M. Stevens, Ryan D. Majkrzak
  • Publication number: 20080245628
    Abstract: An energy absorbing device, in particular a device for single-use occupant protection in vehicles, has a container with a magneto-rheological medium which is forced on impact through a restriction with at least one outlet channel. The flow resistance of the outlet channel may be influenced by a device for generation of a magnetic field.
    Type: Application
    Filed: June 12, 2008
    Publication date: October 9, 2008
    Applicant: INVENTUS ENGINEERING GMBH
    Inventors: Stefan Battlogg, Jurgen Posel
  • Publication number: 20080245627
    Abstract: An energy absorbing element contains a free-flowing medium. The medium is expressed from the element, upon the occurrence of an impact, through at least one opening. The medium is enclosed in a capsule that bursts on impact.
    Type: Application
    Filed: June 12, 2008
    Publication date: October 9, 2008
    Applicant: INVENTUS ENGINEERING GMBH
    Inventors: Stefan Battlogg, Jurgen Posel
  • Publication number: 20080245629
    Abstract: An energy absorbing device, particularly for single-use occupant protection in vehicles on the action of an external force, has a free-flowing medium which is forced through a constriction by a mobile pressure element on the action of an external force. A pull device or tension device pulls on the pressure element on the action of the external force.
    Type: Application
    Filed: June 12, 2008
    Publication date: October 9, 2008
    Applicant: INVENTUS ENGINEERING GMBH
    Inventors: Stefan Battlogg, Jurgen Posel
  • Patent number: 7422709
    Abstract: An electromagnetic rheological (“EMR”) fluid (18) broadly includes a conducting medium (22) and a plurality of micronparticles (24) suspended in the medium (22). Each of the micronparticles (24) includes a magnetically permeable core (26), an electrically insulating coating (28) surrounding the core (26), and a conductive winding (30) at least partially wound around the core (26) so that the coating (28) is disposed between the winding (30) and the core (26). An apparatus (10) constructed in accordance with a preferred embodiment of the present invention broadly includes a deformable membrane (12), a pair of polar opposed plates (14 and 16) coupled to the membrane (12), the EMR fluid (18) filling the membrane (12) and being in communication with a current source (20). Current flowing through adjacent windings (30) induces magnetic fields in the corresponding micronparticles (24) that mutually draw the adjacent micronparticles (30) causing them to move together into a north pole-south pole alignment.
    Type: Grant
    Filed: May 23, 2005
    Date of Patent: September 9, 2008
    Inventor: Crosby Gernon
  • Patent number: 7422092
    Abstract: A damper/strut that can provide variable damping and spring energy storage and dissipation. One embodiment includes an adjustable magnetorheological damper and a mechanically adjustable fluid spring in association with an internal accumulator. A combination of internal and external electromagnets generate the magnetic fields required to activate internally maintained magnetorheological material so that its apparent viscosity undergoes the desired change for a given disturbance. By controlling the strength of the magnetic fields generated in the device, the damping capacity and energy storage of the compressible liquid spring can be affected to provide a semi-active damper that can both dissipate and store energy. The proposed devices can be coupled with a sensor feedback and a control system to provide fast and accurate response force for a variety of engineering applications.
    Type: Grant
    Filed: July 7, 2004
    Date of Patent: September 9, 2008
    Inventors: Gregory Hitchcock, Faramarz Gordaninejad
  • Patent number: 7416062
    Abstract: A magnetorheological device comprising a housing having a divider within the housing is disclosed and claimed. A rotary impeller having two paddles is rotatably mounted within the housing. The rotary impeller sealingly engages the divider and the paddles in combination with the divider forms a first chamber and a second chamber. Magnetorheological fluid resides in the chambers and a passageway interconnects the first and second chambers. A coil surrounds a portion of the passageway such that when energized the magnetorheological fluid solidifies plugging the passageway. As the impeller rotates, it pushes the incompressible fluid against the divider in the housing and the plug in the passageway and retards and/or stops the motion of the impeller.
    Type: Grant
    Filed: October 23, 2003
    Date of Patent: August 26, 2008
    Assignee: The United States of America as represented by the Administrator of the National Aeronautics and Space Administration
    Inventors: Steven M. Arnold, Nicholas Penney
  • Publication number: 20080142320
    Abstract: A damper apparatus includes a housing having a toroidal inner housing surface and a slidably linked piston moveable in the housing having a curved outer peripheral piston surface in engagement with the inner housing surface. A fluid barrier is attached to the housing and located in the housing interior. A flow control passageway and electro-magnetic field control valve defined by either the piston or the damper shaft/arm assembly controls viscosity and passage of magnetic-rheological damper fluid when there is relative rotational movement between the piston and the housing to dampen the forces causing relative rotational movement.
    Type: Application
    Filed: December 13, 2006
    Publication date: June 19, 2008
    Inventor: Norick B. Moradian
  • Patent number: 7386378
    Abstract: A vehicle suspension system that includes a cylinder, a rod inserted within the cylinder, a piston coupled to the rod and a piston valve which has an input piston current. The suspension system further includes a base coupled to the cylinder, a base valve which has an input base current, and a controller coupled to the piston valve and the base valve. The controller is adapted to generate the input piston current and the input base current based on a generated virtual current.
    Type: Grant
    Filed: June 7, 2004
    Date of Patent: June 10, 2008
    Assignee: Tenneco Automotive Operating Company, Inc.
    Inventors: Christophe Lauwerys, Jan Swevers, Paul Sas
  • Publication number: 20080128230
    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: Application
    Filed: June 6, 2007
    Publication date: June 5, 2008
    Applicant: THE HONG KONG POLYTECHNIC UNIVERSITY
    Inventors: Siu Wing Or, Yiqing Ni, Yuanfeng Duan
  • Publication number: 20080105504
    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.
    Type: Application
    Filed: June 22, 2007
    Publication date: May 8, 2008
    Inventors: Eric N. Anderfaas, Dean Banks
  • Patent number: 7364022
    Abstract: Variably controllable motion-damping devices are disclosed that utilize a magneto-rheological fluid (MRF). One configuration of such a device includes a first valving region and a second valving region connected to the first valving region. Between the first and second valving regions is a plate having a first surface adjacent the first valving region and a second surface adjacent the second valving region. At least one of the first and second surfaces is treated to impart a significantly increased shear yield stress to columnized MRF particles passing over the surface, compared to an otherwise similar untreated surface. An MRF is contained in the first and second valving regions such that the MRF can flow through the first and second valving regions. Motion of a first object relative to a second object is damped by causing flow of MRF through the first and second valving regions. A magnet produces a magnetic field within at least one of the valving regions.
    Type: Grant
    Filed: April 4, 2005
    Date of Patent: April 29, 2008
    Assignee: University of Nevada
    Inventors: Faramarz Gordaninejad, Xiaojie Wang, Gregory Hitchcock, Barkan M. Kavlicoglu, Krishna Kiran Bangrakulur
  • Publication number: 20080067019
    Abstract: A magnetorheological (MR) damper includes a damper tube, a movable non-MR damper piston, and a non-movable MR damper piston. The damper tube has substantially hermetically separated first and second chambers, wherein the first chamber contains a non-MR fluid and the second chamber contains an MR fluid. The non-MR damper piston is located in the first chamber and is slidable with respect to the damper tube. The MR damper piston has a longitudinal axis and an electric coil, is located in the second chamber, and is fixedly attached to the damper tube. Sliding the non-MR damper piston with respect to the damper tube causes movement of at least some of the MR fluid longitudinally past the electric coil.
    Type: Application
    Filed: September 19, 2006
    Publication date: March 20, 2008
    Inventors: Eric L. Jensen, Michael W. Hurtt, David Andrew Shal, Michelle Goecke, Benoit Prevot, Lilian Cantuern, Jocelyn Marchand, Christophe Francisco
  • Publication number: 20080053763
    Abstract: A system and method for self-powered magnetorheological-fluid damping of mechanical vibrations includes a hydraulic cylinder. The hydraulic cylinder is configured for at least partially disposing magnetorheological fluid therein. A piston head is disposed within the hydraulic cylinder. The piston head has first and second sides and is configured to be in sliding engagement with the hydraulic cylinder. A piston rod is at least partially disposed within the hydraulic cylinder and is connected to the piston head on the first side. The system also includes a vibration absorber assembly having housing. The vibration absorber assembly is configured to transduce mechanical vibrations of the piston rod to electric current.
    Type: Application
    Filed: August 8, 2007
    Publication date: March 6, 2008
    Inventors: Norman Wereley, Young-Tai Choi
  • Publication number: 20080041676
    Abstract: Vibration suppression systems and methods for isolating payloads from vibrational forces are provided. A gas spring has a housing and a piston within the housing. The piston is mechanically isolated from the housing via a magneto-rheological (MR) fluid gasket. A payload is coupled to the piston, and net gas pressure force is applied to the piston by respectively exposing the first and second piston surfaces to first and second gas pressures. The piston is allowed to be displaced relative to the housing in response to a vibration applied to the housing. A magnetic field is selectively applied to the MR fluid gasket to alternately transform the properties of the MR fluid gasket between primarily viscous and primarily elastic.
    Type: Application
    Filed: September 11, 2006
    Publication date: February 21, 2008
    Applicant: IPTRADE, INC.
    Inventors: Baruch Pletner, Grace Rose Kessenich, Shweta Bhola
  • Patent number: 7308975
    Abstract: A velocity sensor including a damper assembly having a central axis, a magnet extending parallel to the central axis, the magnet having a magnetic axis radially oriented with the central axis, and a coil extending parallel to the central axis and radially oriented with the central axis, wherein movement of the damper assembly with respect to the magnet induces a voltage in the coil.
    Type: Grant
    Filed: December 6, 2004
    Date of Patent: December 18, 2007
    Assignee: Delphi Technologies, Inc.
    Inventors: Thomas W. Nehl, Fang Deng
  • Patent number: 7303056
    Abstract: A controllable magnetorheological (MR) damper having first, second and third portions is disclosed. The first and second portions have a translational degree of freedom therebetween, and the third portion has a rotational degree of freedom with respect to the first and second portions. The first and third portions are coupled via a translation-to-rotation converter, and the second and third portions are coupled via a magnetorheological (MR) fluid. A bearing is disposed between the first and second portions for supporting a side load therebetween, a magnetic field generator is in field communication with the magnetorheological fluid, and a signal path is in signal communication with the magnetic field generator.
    Type: Grant
    Filed: December 9, 2004
    Date of Patent: December 4, 2007
    Assignee: General Motors Corporation
    Inventor: Chandra S. Namuduri
  • Patent number: 7293633
    Abstract: A controlled damper assembly includes a controlled-damper-assembly piston, a controlled-damper-assembly piston rod attached to the piston, an insulated wire, and an electrical connector. The insulated wire is positioned in the piston rod, has a first end operatively connected to the piston, and has a second end. The electrical connector has a first connection terminal electrically connected to the second end of the insulated wire and has a second connection terminal electrically connected to the piston rod. An example, without limitation, of a controlled damper assembly is a magnetorheological damper assembly.
    Type: Grant
    Filed: December 20, 2004
    Date of Patent: November 13, 2007
    Assignee: Delphi Technologies, Inc.
    Inventors: Saiman Lun, Ilya Lisenker