Magnetostrictive-type Device Patents (Class 335/215)
  • Patent number: 6307286
    Abstract: A super magnetostrictive actuator includes: a magnetic field generating unit, at least first and second super magnetostrictive members extensible in a longitudinal direction thereof due to action of magnetic field generated by the magnetic field generating unit, and a coupling member having a cylindrical shape and disposed coaxially between the first and second super magnetostrictive members. The second super mangetostrictive member has a cylindrical shape and is coaxially disposed to surround the outside of the first super magnetostrictive member in a radial direction thereof. Both end portions of the coupling member are coupled to one end portion of the first super magnetostrictive member and one end portion of the second super magnetostrictive member, respectively.
    Type: Grant
    Filed: February 29, 2000
    Date of Patent: October 23, 2001
    Assignee: Honda Giken Kogyo Kabushiki Kaisha
    Inventors: Hideharu Yamazaki, Akifumi Otaka, Hiroyuki Goto
  • Patent number: 6300855
    Abstract: A high power magnetostrictive transducer element comprising a material of the formula TbxDyyHozFe2−w wherein 0.24≦x≦0.28, 0.52≦y≦0.56, 0.13≦z≦0.22, x+y+z=1, and 0≦w≦0.20 and wherein the material is prestressed by a compressive force of from about 5 to about 100 MPa.
    Type: Grant
    Filed: December 21, 1998
    Date of Patent: October 9, 2001
    Assignee: The United States of America as represented by the Secretary of the Navy
    Inventors: Arthur E. Clark, James B. Restorff, Marilyn Wun-Fogle
  • Patent number: 6192096
    Abstract: A magnetostrictive wire control rod position detector assembly which will allow nuclear reactor output to be increased, control performance to be improved, and peripheral equipment to be rationalized by continuously and accurately detecting the position of a control rod in a reactor core is provided. A magnetostrictive wire control rod position detector assembly (20) comprises: a magnet or magnets (21) mounted on a non-magnetic portion of a movable member (3) which is free to move in the longitudinal direction on the inside of a cylindrical member (1) and is partly composed of a non-magnetic material; a magnetostrictive wire detector (22) longitudinally mounted on the outer circumference of said cylindrical member, which is provided with a receiver (26); and a pulsed current generator circuit (37) which supplies a pulsed current from the receiver end to the magnetostrictive wire of the magnetostrictive wire detector.
    Type: Grant
    Filed: April 30, 1999
    Date of Patent: February 20, 2001
    Assignee: Mitsubishi Heavy Industries, Ltd.
    Inventors: Toshio Ichikawa, Yoshiaki Makihara, Syo Imayoshi
  • Patent number: 5907269
    Abstract: A magnetostrictive clamping device which includes first and second arm members having respective first and second end portions. The first and second arm members are interconnected to permit relative movement between the first and second end portions between a first position in which the first and second end portions are spaced apart and a second position in which the first and second end portions are spaced closer together. An actuator is included for causing relative movement between the first and second arm members from the first position to the second position. The actuator has a drive element made from a magnetostrictive material. An electromagnetic field extends through at least a portion of the drive element. The drive element is changeable between a first shape when in the absence of the electromagnetic field and a second shape when in the presence of the electromagnetic field.
    Type: Grant
    Filed: June 6, 1997
    Date of Patent: May 25, 1999
    Assignee: Etrema Products, Inc.
    Inventor: Rick L. Zrostlik
  • Patent number: 5857492
    Abstract: A manually operable control device, such as a joystick, includes a plurality of actuators for operating hydraulic valves of a machine. A handle has a sphere received within a cavity formed between a pair of seat portions which are moveable with respect to each other. The handle produces movement of at least one of the plurality of actuators when the sphere is pivoted within the cavity. An electromagnetic coil generates a magnetic field that causes the seat portions to be attracted toward each other which increases friction between the sphere and the seat. A control circuit applies electric current to the electromagnetic coil whenever the machine is turned on and disconnects the electric current when the machine is turned off. The friction between the sphere and the seat holds the control device in an operating position set by the machine operator and springs return the control device to a neutral position when the machine is turned off.
    Type: Grant
    Filed: March 20, 1998
    Date of Patent: January 12, 1999
    Assignee: HUSCO International, Inc.
    Inventor: Charles P. Salamun
  • Patent number: 5792284
    Abstract: Magnetostrictive powder composite and method for the manufacturing of the magnetostrictive powder composite. The composite comprises magnetostrictive powder grains with chemical composition (RE).sub.x T.sub.1-x, where RE represents one or a mixture of several rare earth metals, T represents iron, nickel, cobalt, manganese or a mixture of these metals and x represents atomic fraction assuming a value between 0 and 1, whereby the grains are held together by a binder. The magnetostrictive grains constitute greater than 60 percent by volume of the composite. The composite is produced by pressing together magnetostrictive powder grains and the binder. Isostatic pressure may be used in the pressing step.
    Type: Grant
    Filed: May 15, 1995
    Date of Patent: August 11, 1998
    Assignees: Fox Technology KB, Proengco AB
    Inventors: Tord Cedell, Lars Sandlund
  • Patent number: 5745039
    Abstract: A remote sterilization indicator is described. The indicator allows a sterilization cycle to be monitored without the need to visually inspect the indicator.
    Type: Grant
    Filed: February 21, 1997
    Date of Patent: April 28, 1998
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: Craig R. Hof, Gary Focarino, Samuel David Lannigan, Raymond A. Hof
  • Patent number: 5739600
    Abstract: Provided is an underwater magnetrostrictive vibration device with reduced signal attenuation and improved in efficiency and sound quality, which has been low due to external noise disturbance.
    Type: Grant
    Filed: March 19, 1996
    Date of Patent: April 14, 1998
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Tadahiko Kobayashi, Isao Sakai, Kiyohisa Hinohara
  • Patent number: 5703553
    Abstract: A magnetostrictive active member configured to withstanding significant bending moments and having a prestress mechanism that is adjustable for maintaining optimal performance of an integral magnetostrictive element. The magnetostrictive active member includes a magnetostrictive actuator and parallel flexures incorporated in a housing to create a load path for bending moments to be carried by the housing, through the parallel flexures, as opposed to being carried by the magnetostrictive actuator. A plurality of ball-joints are integrated with the flexures and magnetostrictive actuator, receiving compressire forces and ensuring that no moments are applied to the magnetostrictive actuator. A prestress or preload mechanism is incorporated which provides a compressire preload to the magnetostrictive actuator internal to the housing. The preload mechanism includes an adjustable nut than is externally accessible to adjust the preload and facilitate optimal performance of the magnetostrictive actuator.
    Type: Grant
    Filed: May 24, 1996
    Date of Patent: December 30, 1997
    Assignee: SatCon Technology, Corp.
    Inventors: Dariusz Antoni Bushko, Kevin Michael Avakian, Bruce Graham Johnson, Michael Jonathan Gerver
  • Patent number: 5693154
    Abstract: Polycrystalline or single crystal magnetostrictive alloys of the formula Tb.sub.1-x Dy.sub.x Zn.sub.w (0<x.ltoreq.0.7; 0.90.ltoreq.w.ltoreq.1.10) and Tb.sub.1-y Gd.sub.y Zn.sub.w (0<y.ltoreq.0.4; 0.90.ltoreq.w.ltoreq.1.10) and magnetostrictive transducer elements made of these alloys.
    Type: Grant
    Filed: April 3, 1996
    Date of Patent: December 2, 1997
    Assignee: The United States of America as represented by the Secretary of the Navy
    Inventors: Arthur E. Clark, James B. Restorff, Marilyn Wun-Fogle
  • Patent number: 5588466
    Abstract: A magnetostrictive transducer wherein a magnetostrictive layer is applied to a flexible element, for example, a flexible beam. The flexible element is deflected by an external magnetic field. The thin magnetostrictive layer consists of Tb.sub.(1-x) Dy.sub.(x) Fe.sub.2.
    Type: Grant
    Filed: December 20, 1994
    Date of Patent: December 31, 1996
    Assignee: Robert Bosch GmbH
    Inventors: Gerhard Benz, Gottfried Flik, Christoph Treutler, Heinz Friedrich
  • Patent number: 5585772
    Abstract: An actuator in which a magnetostrictor is subjected to magnetic fields produced by a superconducting coil, and the magnetostrictor and coil are maintained at temperatures below the magnetic transition temperature of the magnetostrictor and the superconducting temperature of the coil, typically at temperatures in the range of about 4 to about 130 degrees Kelvin. The magnetostrictor is a laminated Terbium Dysprosium (TbDy) alloy structure and the coil includes high temperature superconducting oxide material. The laminations of the TbDy structure are mechanically loaded in compression and each has a thickness substantially equal less than or equal to the depth of field penetration, and a cooler maintains both the TbDy and superconductor at their optimum temperatures.
    Type: Grant
    Filed: January 11, 1995
    Date of Patent: December 17, 1996
    Assignee: American Superconductor Corporation
    Inventors: Chandrashekhar H. Joshi, John P. Voccio, Anthony J. Rodenbush, Carl J. Russo
  • Patent number: 5565830
    Abstract: A rare earth-cobalt supermagnetostrictive alloy having a composition represented by the general formula, in atomic fraction: R (Co.sub.1-x Fe.sub.x).sub.x, wherein 0.001.ltoreq.x.ltoreq.0.8, 0.2.ltoreq.z.ltoreq.15, and R is at least one element selected from the group consisting of Sc, Y, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu and is consisting essentially of a cubic system whose easy axis of magnetization is generally <100> or <110> oriented; or R (Co.sub.1-x Fe.sub.x).sub.x, wherein 0.001.ltoreq.x.ltoreq.0.8, 0.2.ltoreq.z.ltoreq.15, and R is at least one element selected from the group consisting of Sc, Y, La, Ce, Pr, Nd, Sm, Gd, Dy, Er, Yb, and Lu. Such an alloy exhibits satisfactory magnetostriction in a wide range of temperatures from room temperature to liquid nitrogen temperature.
    Type: Grant
    Filed: November 29, 1993
    Date of Patent: October 15, 1996
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Masashi Sahashi, Tadahiko Kobayashi
  • Patent number: 5414397
    Abstract: The invention relates to an elastic clamping device for at least one body with magnetostrictive properties, wherein a pressure force presses the clamping device against the inner magnetostrictive body with a predetermined force. The pressure force extends in the direction of contraction and perpendicular to the direction of expansion both caused by the influence of a magnetic field on the magnetostrictive body and results in a prestress acting in the direction of contraction in the magnetostrictive body. The predetermined pressure from the pressure force exerted on the clamping device and thus on the magnetostrictive body is adjustable by means of a resilient force or mechanical setting device.
    Type: Grant
    Filed: April 7, 1993
    Date of Patent: May 9, 1995
    Assignee: Dynamotive Corp.
    Inventor: Lothar E. Kiesewetter
  • Patent number: 5396266
    Abstract: A kinesthetic feedback apparatus and method whereby braking forces are imposed on a hand-movable lever. The lever is either a joystick or a uniplanar lever, and the braking forces are imposed by a friction plate being pressed against a portion of the lever by a length of magnetostrictive material. An electromagnetic coil around the magnetostrictive material receives a signal from a remote apparatus driven by movement of the lever. The magnitude of the signal is a function of the resistive forces encountered by the remote apparatus so that the braking forces are directly proportional to the resistive forces thereby providing kinesthetic feedback to the person operating the lever.
    Type: Grant
    Filed: June 8, 1993
    Date of Patent: March 7, 1995
    Assignee: Technical Research Associates, Inc.
    Inventor: Owen D. Brimhall
  • Patent number: 5361053
    Abstract: In a super magnetostriction type actuator constructed such that a super magnetostriction rod is extended/contracted by application of a magnetic field from a solenoid coil, and a drive object is moved in response to the extension/contraction, a locating member for locating the super magnetostriction rod thermally deforms in correspondence with a thermal expansion of the super magnetostriction rod so as to permit an extension of the super magnetostriction rod due to the thermal expansion thereof. As a result, variation in spring loading and lift with thermal expansion of the super magnetostriction rod can be avoided. Also, the magnetostriction characteristic of the locating member is opposite that of the super magnetostriction rod allowing for greater relative movement of the super magnetostriction rod upon application of a magnetic field.
    Type: Grant
    Filed: October 7, 1993
    Date of Patent: November 1, 1994
    Assignee: Unisia Jecs Corporation
    Inventors: Yuichi Hosokawa, Kazumitsu Kobayashi, Tomoichi Misawa
  • Patent number: 5357232
    Abstract: A magnetostrictive element includes a magnetostrictive member, an outer magnet disposed coaxially about, spaced apart from, and surrounding the magnetostrictive member, and a soft magnetic yoke for magnetically coupling the magnetostrictive member and the outer magnet to form a closed magnetic circuit. The magnetostrictive member may be either solid or hollow. In the latter case, an inner magnet is disposed coaxially within the magnetostrictive member for producing a biased DC magnetic field. An axial length of the outer magnet is made shorter than an axial length of the magnetostrictive member. In either case, the outer magnet is spaced apart from the magnetostrictive member so that a more uniform magnetization distribution is produced in the magnetostrictive member.
    Type: Grant
    Filed: December 2, 1992
    Date of Patent: October 18, 1994
    Assignee: TDK Corporation
    Inventors: Kazutaka Suzuki, Teruo Mori
  • Patent number: 5172020
    Abstract: A magnetic core employed in AC motors, transformers and the like includes a first core portion formed by laminating silicon steel sheets each containing 3.5% silicon, the first core portion having two ends in the direction that the sheets are laminated, and second core portions disposed at the respective ends of the first core portion and formed by laminating silicon steel sheets each containing 6.5% silicon. In distorted wave alternating field, low frequency fluxes pass through the first core portion and harmonic fluxes pass through the second core portions. Since each second core portion has a low level of magnetostriction, the magnetic noise due to the harmonics is reduced.
    Type: Grant
    Filed: December 18, 1990
    Date of Patent: December 15, 1992
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Sadayoshi Hibino, Motoyasu Mochizuki, Tadayuki Sato
  • Patent number: 5101183
    Abstract: Apparatus and a method for restraining the movement of members due to magnetic fields in which a clamp made of magnetostrictive materials is used.
    Type: Grant
    Filed: September 11, 1989
    Date of Patent: March 31, 1992
    Assignee: British Aerospace Public Limited Company
    Inventor: David G. Dixon
  • Patent number: 5070316
    Abstract: The invention relates to a special embodiment of a plate which is to be able to transmit movement and compressive force as well as possess soft-magnetic properties with low losses and low reluctance. The latter requirement means, inter alia, that the plate, upon loading, will be subjected to a relatively great elastic deformation with an ensuing reduced ability to transmit movement and compressive force. By perforating the plate with a number of evenly distributed holes provided with pellets of a stiff resistant material with an axial length at least as great as the thickness of the plate, movement and compressive force may be transmitted from a compressive force-generating element via the plate to a compressive force-absorbing element without the plate being elastically deformed.
    Type: Grant
    Filed: October 26, 1990
    Date of Patent: December 3, 1991
    Assignee: ABB Atom AB
    Inventors: Goran Engdahl, Dag Wikstrom
  • Patent number: 5037184
    Abstract: Oppositely polarized magnets are secured to a deformable mirror and a corresponding actuator. They rely on magnetic attraction to maintain the connection between the actuator and mirror. A reverse magnetic field is imposed when the actuator is to be removed for repair.
    Type: Grant
    Filed: December 18, 1989
    Date of Patent: August 6, 1991
    Assignee: United Technologies Corporation
    Inventor: Mark A. Ealey
  • Patent number: 4993843
    Abstract: The device comprises a transparent tube (1) wherein may slide freely a part (4) at the extremities of which are arranged two small magnetic masses (5,6). The tube (1), closed at both ends, forms a sealed tank wherein there is placed a phase changing material (7) which is either in a liquid state or in a solid state, according to the temperature to which it has been brought. At one of the ends of the tube (1) a cap (12) containing a removable magnet (9a) is fitted. A fixed magnet (11) is placed at the other end of the tube (1). The part (4) being initially placed on the side of the cap (12), the material (7) is solidified and the removable magnet (9a) is then removed. In the case of exceeding the melting temperature of the material (7), the part (4) attracted by the magnet (11) moves towards the corresponding end of the tube (1), thus making visible a colored ring (14).
    Type: Grant
    Filed: March 21, 1988
    Date of Patent: February 19, 1991
    Assignee: Xavier Douesnel
    Inventors: Joseph Toupin, Xavier Douesnel
  • Patent number: 4975643
    Abstract: Apparatus and method for precisely controlling the movement of a magnetostrictive transducer including an elongated magnetostrictive rod, means for inducing a magnetic field in the rod and supplying drive current for moving the rod in response to the drive current. A temperature compensated strain sensor configuration on the rod detects the amount of rod movement in response to the drive current and provides an output signal proportionate thereto. Feedback control means coupled between the strain sensor and the current driver respond to the strain sensor output signal and vary the drive current until the strain sensor output signal matches the voltage reference set point developing the drive current.
    Type: Grant
    Filed: April 5, 1989
    Date of Patent: December 4, 1990
    Assignee: Fisher Controls International, Inc.
    Inventor: Warren G. Buchwald
  • Patent number: 4959567
    Abstract: A magnetodistortive actuator includes an elongated active component of a magnetodistortive material mounted on a support and having a stationary and a movable end portion. At least one permanent magnet applied a permanent magnetic bias to the active component to bring it to a desired point of its stress/field characteristic line. The strength of that portion of the magnetic field of the permanent magnet that acts on the active component is selectively varied by changing the magnetic reluctance of a body that is accommodated in a space interposed between the permanent magnet and the active component. The active component is further subjected to a variable magnetic field generated by a solenoid surrounding the active component, so that the active component is selectively shortened and lengthened around its length corresponding to the desired point, with attendant movement of the movable end portion relative to the support.
    Type: Grant
    Filed: December 20, 1988
    Date of Patent: September 25, 1990
    Assignee: United Technologies Corporation
    Inventors: Mark A. Ealey, Robert L. Lillard
  • Patent number: 4914412
    Abstract: A specially designed magnetic circuit which is provided which is intended to magnetize cylindrically shaped magnetic materials (1) in the axial direction. The magnetic circuit comprises a magnetizing coil (2), permanent magnets (5, 6), and magnetic return conductors (3, 7) of a ferromagnetic material. The magnetic circuit is well suited to utilize the magnetostrictive properties of a magnetic material.
    Type: Grant
    Filed: April 24, 1989
    Date of Patent: April 3, 1990
    Assignee: Asea Brown Boveri AB
    Inventors: Goran Engdahl, Lars Kvarnsjo
  • Patent number: 4850716
    Abstract: A monitor for detection of temperature and/or steam conditions indicative of sterilization. The monitor comprises means for creating a remotely detectable response upon interrogation by an electromagnetic field and means for changing the response upon exposure to a predetermined set of temperature and steam conditions. The remotely detectable response is preferably produced through the interaction of an electromagnetic interrogation field with magnetic components of the monitor, wherein the characteristic harmonic response generated by the magnetic components is either inhibited or enabled by the change in configuration of one or more elements of the detector. Sterilization conditions are detected through one or more compounds known to have melting points which are above the temperature used in the sterilization process. Melting of the chemical compound produces the change in configuration of the element or elements of the monitor.
    Type: Grant
    Filed: November 20, 1987
    Date of Patent: July 25, 1989
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: Dennis L. Baker, Steven S. Kirckof, Dan J. Morse, Chester Piotrowski
  • Patent number: 4845450
    Abstract: The drive modules of a magnetostrictive transducer are fabricated from interleaved permanent magnet disks (samarium cobalt) and high-strain, low-permeability magnetostrictive lanthanide alloy (Terfenol-D) disks to form a stack of such interleaved materials of substantially uniform magnetic field distribution in the stack. Two such stacks in side-by-side relationship provide a series-aiding magnetic circuit completed through high-permeability flux return pole pieces at their ends thereby providing a substantially uniform magnetic field distribution in the stack. Each stack has longitudinally-extending and electrically-insulated planar cuts and each flux return pole piece is a laminate of thin sheets of high-permeability electrically-insulated steel to reduce eddy current losses resulting from the AC field. The steel sheets are constrained by a nonmagnetic end-block into which the steel sheets are inserted and bonded.
    Type: Grant
    Filed: June 2, 1986
    Date of Patent: July 4, 1989
    Assignee: Raytheon Company
    Inventors: Raymond Porzio, William J. Harrold, James R. Sturges
  • Patent number: 4644310
    Abstract: An actuator system comprises a magnetomechanical cantilever beam adapted to be responsive to magnetic fields of various magnitudes. The system provides precise and rapid repositioning of the free end of the beam corresponding to the magnitude of the applied magnetic field. The beam is comprised of magnetostrictive ferromagnetic amorphous material and provides efficient, high force, high speed actuation to devices requiring electronically controlled variable displacement motion.
    Type: Grant
    Filed: March 22, 1984
    Date of Patent: February 17, 1987
    Assignee: Allied Corporation
    Inventors: Philip M. Anderson, III, Jeffrey C. Urbanski
  • Patent number: 4599591
    Abstract: A magnetostrictive transducer utilizing magnetostrictive material and a plurality of windings connected to current sources having a phase relationship so as to establish a rotating magnetic induction vector within the magnetostrictive material.
    Type: Grant
    Filed: May 8, 1985
    Date of Patent: July 8, 1986
    Assignee: Westinghouse Electric Corp.
    Inventors: Robert M. Delvecchio, Karl Foster
  • Patent number: 4397381
    Abstract: Drum-type brakes and band-type clutches which are activated by expansion or compression, or both, of one or more concentric magnetic members, with conducting windings carrying electric currents. Circular annular mating members carrying one or more conducting windings expand or contract in diameter, due to magnetic forces caused by currents in the winding or windings, and operate as a brake or a clutch.
    Type: Grant
    Filed: November 27, 1981
    Date of Patent: August 9, 1983
    Inventors: Charles B. Fisher, Sidney T. Fisher
  • Patent number: 4369344
    Abstract: A sensitive edge 10 for door systems, lifts, doors, or other moving portions of transit vehicles that come into contact with articles or passengers includes a body defining a resilient deformable leading edge portion 30 and a base portion 32 within which is defined an internal chamber. A coupling portion is defined on and extending from the base for coupling the sensitive edge to the door or similar device 36. The chamber 34 is hollow and at atmospheric pressure and in the preferred embodiment, is filled with air. Within the chamber is mounted a Wiegand wire and pick-up coil 38 that is electrically coupled to a switch for recycling the door or similar device upon engagement of the sensitive edge with an object such as a passenger.
    Type: Grant
    Filed: July 26, 1979
    Date of Patent: January 18, 1983
    Assignee: Vapor Corporation
    Inventor: John A. Diamond
  • Patent number: 4158368
    Abstract: Improved magnetostrictive materials are combined in a novel arrangement to provide a transducer of the electromechanical type particularly suited for the precise control of fluid flow. An embodiment according to this invention comprises a valve assembly having a discharge ported, cylindrical housing of a material exhibiting positive magnetostriction, a plunger of a material exhibiting negative magnetostriction disposed within the housing, the plunger provided with a tapered nose initially in close fitment within the discharge port to restrain the flow of fluids, and means to create a magnetic field around the assembly. As the materials are exposed to the magnetic field the housing expands relative to the contracting plunger, causing the plunger to separate from close, seated fitment within the discharge port, thereby allowing flow through the port. One of the materials may be selected from a non-magnetostrictive material.
    Type: Grant
    Filed: May 12, 1976
    Date of Patent: June 19, 1979
    Assignee: The United States of America as represented by the Secretary of the Navy
    Inventor: Arthur E. Clark
  • Patent number: 4151432
    Abstract: A ferrite for magnetostrictrive vibrators is produced by the simple process of press forming a preformed structure formed from starting powder of magnetite or a mixture of magnetite and ferric oxide, said powder having an average particle size d (.mu.) of from 0.02 to 5.0 .mu., sintering this structure in an atmosphere wherein the partial pressure of oxygen is from 10.sup.-1 to 10.sup.-11 atmosphere at a temperature of from 1,000.degree. to 1,350.degree. C. and which will meet the requirement:140 log d+1,305.gtoreq.T(.degree.C.).gtoreq.160 log d+1,180and thereafter cooling the structure thus sintered to room temperature at a cooling rate m (.degree.C./min.) <0.5f where f(KHz) is a corresponding resonance frequency thereby to produce a macroscopically homogeneous ferrite structure containing as its principal constituent a sintered magnetite having an oxygen/iron (O/Fe) atomic ratio of 4.0/3<0/Fe<4.1/3, and a density of at least 90% of the theoretical density.
    Type: Grant
    Filed: March 4, 1976
    Date of Patent: April 24, 1979
    Assignee: Mitsubishi Kinzoku Kabushiki Kaisha
    Inventors: Yumi Akimoto, Tamotsu Ishii, Motohiko Yoshizumi, Sadaaki Haghino
  • Patent number: 3961297
    Abstract: Devices relying on the Inverse Wiedman Effect. Devices include a current conductive, magnetically anisotropic rod, through which an AC current flows. Wound about the rod is a conductive coil having output terminals. By varying the AC current, the anisotropy, or both, variations in the output across coil terminals can be obtained. Devices may be for current sensing, pressure sensing, fluid flow sensing or an electric push button.
    Type: Grant
    Filed: July 12, 1974
    Date of Patent: June 1, 1976
    Inventor: Ivan J. Garshelis
  • Patent number: 3959751
    Abstract: Electromechanical transducer comprising a helically wound, magnetostrictive rod that is circularly magnetized. Surrounding said rod is a conductive coil.
    Type: Grant
    Filed: July 12, 1974
    Date of Patent: May 25, 1976
    Inventor: Ivan J. Garshelis
  • Patent number: 3939448
    Abstract: Mechanically controllable magnet made of a magnetostrictive, circularly magnetically anisotropic, circularly magnetized rod. There is no apparent magnetism externally. When rod is twisted, circular anisotropy becomes helical and circular magnetization also becomes helical to produce an axial field component and hence externally apparent magnetism. When rod untwists, it restores itself to its apparently non-magnetic condition.
    Type: Grant
    Filed: July 12, 1974
    Date of Patent: February 17, 1976
    Inventor: Ivan J. Garshelis
  • Patent number: 3932112
    Abstract: Devices relying on the Inverse Wiedemann Effect. In all instances, magnetostrictive rods are circularly magnetized and exhibit hysteresis when plotting axial induction vs. twist. Hysteresis, especially when rectangular, yields high d.phi./dt upon twisting to result in large output voltage across terminals of coil wound about the rod. In other embodiments, rectangular hysteresis gives rise to one-shot electric push button or sequential switch. Hysteretic magnetostrictive circularly magnetized rods also serve as recording devices to detect mechanical movement or shock.
    Type: Grant
    Filed: July 12, 1974
    Date of Patent: January 13, 1976
    Inventor: Ivan J. Garshelis