With Flux Leakage-reducing Means Patents (Class 335/304)
  • Patent number: 7504918
    Abstract: An apparatus for sensing relative positions of mechanically coupled devices. The apparatus includes a magnetically actuated switch connected to a set of flux conductors to form a switch assembly. A permanent magnet is affixed to a set of flux conductors to form a magnet assembly. The flux conductors are positioned adjacently to conduct flux from the permanent magnet to the magnetically actuated switch. Movement of either assembly results in the reduction of flux conduction between the magnet and the magnetically actuated switch. The apparatus can be integrated into a helmet mount for night vision goggles to sense the relative position of the helmet mount for controlling the operation of the night vision goggle.
    Type: Grant
    Filed: June 23, 2006
    Date of Patent: March 17, 2009
    Assignee: Norotos, Inc.
    Inventors: Jonathon R. Prendergast, Charles R. Patton, III
  • Publication number: 20090039995
    Abstract: A permanent magnet device includes a polarized permanent annular magnet having two oppositely charged poles faces. A magnetically conductive faceplate is disposed on each of the opposite pole faces of the permanent magnet. Each faceplate is sized, shaped and oriented to equally distribute the flux lines emanating from the permanent magnet, and to increase or concentrate the density of the magnetic flux field of a permanent magnet or permanent magnet device.
    Type: Application
    Filed: July 8, 2008
    Publication date: February 12, 2009
    Inventors: Ronald Kipp, Steven W. Day, Don B. Olsen
  • Patent number: 7467780
    Abstract: An electromagnetic valve is provided with an elongated tappet guided axially displaceably in a tappet guide, and with a sealing body, embodied on the tappet, that can seal against a sealing seat. So that the valve can be produced more economically yet can be regulated more precisely, the sealing seat and the tappet guide are embodied in one piece. The adjustability of the valve is assured in particular by an adjusting ring.
    Type: Grant
    Filed: December 13, 2004
    Date of Patent: December 23, 2008
    Assignee: Robert Bosch GmbH
    Inventor: Dietmar Kratzer
  • Patent number: 7365623
    Abstract: The present invention provides a permanent magnet, comprising a cylinder formed with a permanent magnetic material. The cylinder comprises along a radial direction, a magnetic core and a magnetic sheath that are coaxial. The magnetic core is assembled in the magnetic sheath. The magnetization direction of the magnetic core is axial direction, and the magnetization direction of the magnetic sheath changes step by step from a direction which is parallel to the magnetization direction of the magnetic core in one end to a direction which is orthogonal to the magnetization direction of the magnetic core in the other end, along the axial direction of the cylinder. Moreover, a magnetic device for use in MRI using the magnet and manufacturing methods for the permanent magnet and the magnetic device are also provided in the present invention. With the permanent magnet, magnetization strength in the working area generated by the magnetic device for use in MRI can amount to more than 0.5-0.6 T.
    Type: Grant
    Filed: April 27, 2006
    Date of Patent: April 29, 2008
    Assignee: Beijing Taijie Yanyuan Medical Engineering Technical Co., Ltd.
    Inventor: Pingchou Xia
  • Patent number: 7248047
    Abstract: A trailer for housing a mobile MRI system has magnetic shielding in the form of a plurality of sheets of magnetic material which are supported within the trailer, by a rigid supporting structure or frame. The layers are arranged in a stacked or laminar configuration with the laterally longest layer disposed inward of the remaining layers, such that the width of the gap between that layer and the exterior walls of the trailer at the lateral extremities of the shielding is greater than its width in a central area. The rigid frame maintains the gap and prevents contacting of the shielding and the trailer walls.
    Type: Grant
    Filed: August 19, 2005
    Date of Patent: July 24, 2007
    Assignees: Siemens Magnet Technology Ltd., Siemens Medical Solutions USA, Inc
    Inventors: Michael John Disney Mallett, Michael Pietsch, Michael Alan Senseney, Joshua Andrew Simmers, Stephen Paul Trowell, Neil Charles Tigwell, Jeremy Francis Williams, Seth Michael DeMarrais
  • Patent number: 7161453
    Abstract: A magnet assembly comprising a magnet mounted for pivoting about a first axis spaced from the magnet, and rotating about a second axis that is perpendicular to and intersects with the first axis. The magnet comprising a plurality of segments each with a magnetization direction such that through a combination of pivoting and rotating the magnet projects a magnetic field in any direction at an operating point spaced from the front of the assembly. The segmented construction with segments of different magnetization directions allows small changes in the orientation of the magnet to substantially change the magnet field direction at a system operating point.
    Type: Grant
    Filed: December 7, 2005
    Date of Patent: January 9, 2007
    Assignee: Stereotaxis, Inc.
    Inventor: Francis M. Creighton, IV
  • Patent number: 7084632
    Abstract: The present invention discloses a permanent magnet for magnetic resonance, which is used for a magnetic resonance imaging apparatus for medical diagnosis. The permanent magnet of the present comprises permanent magnetic material; pole heads; plates for eliminating vortex (i.e. eddy currents); rings for homogenizing the magnetic field; gradient coils; and a yoke, said yoke of the permanent magnet has an integral and substantially C-shaped structure formed with two columns and is an open type configuration. This invention fully ensures the parallelism of the lower and upper poles, greatly improves the mechanical strength of the yoke, and results in a good magnetic uniformity and a consistent magnetic current.
    Type: Grant
    Filed: March 28, 2003
    Date of Patent: August 1, 2006
    Assignee: Shenyang Neusoft Bopu NMR Tech Co., Ltd.
    Inventors: Shengqian Xiao, Shijie Zhao, Guangran Chen
  • Patent number: 6963181
    Abstract: A color cathode-ray tube apparatus having: a glass bulb including a face panel, a funnel, and a neck; a deflection yoke attached to the funnel to surround thereof; and a color-selection electrode disposed inside the face panel. A pair of degaussing coils are wound around the upper and lower portions of the glass bulb, respectively. A loop coil, which is disposed around the glass bulb between the color-selection electrode and the deflection yoke, includes: a first portion including two extending portions of the loop coil positioned over and below the glass bulb respectively, each center of the extending portions being substantially in a plane perpendicular to a tube axial of the glass bulb; and a second portion including two bent portions that are formed by bending right and left sides of an original form of the loop coil toward the neck.
    Type: Grant
    Filed: May 13, 2003
    Date of Patent: November 8, 2005
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Shigeo Nakatera, Tomohisa Mikami, Tetsuro Ozawa
  • Patent number: 6946939
    Abstract: It is an object to provide a package for a magnetic circuit, with which a leakage magnetic field escaping from an aperture of a magnetic circuit is reduced and the magnetic attraction acting on the packaging plates is lowered, thus reducing the number of packaging work steps. There are provided a packaging plate for a permanent magnet-type magnetic circuit, the packaging plate comprising at least one non-magnetic layer and at least one magnetic layer; and a method for packaging a permanent magnet-type magnetic circuit, comprising a step of shielding at least a portion of an aperture of a permanent magnet-type magnetic circuit using at least one packaging plates.
    Type: Grant
    Filed: September 10, 2004
    Date of Patent: September 20, 2005
    Assignee: Shin-Etsu Chemical Co., Ltd.
    Inventor: Yuhito Doi
  • Patent number: 6897751
    Abstract: A magnetic field generator comprises a pair of pole-piece units. The pair of pole-piece units respectively include plate yokes. Each of the plate yokes includes a surface facing the other's and provided with a permanent magnet group and a pole piece. The pole piece includes an annular projection having a plurality of annular-projection pieces and a permanent magnet for reduction of magnetic flux leakage installed on an outside surface of each annular-projection piece. The permanent magnet for reduction of magnetic flux leakage may be disposed with a magnetizing direction thereof being slanted with respect to a main surface of the permanent magnet group.
    Type: Grant
    Filed: July 9, 2004
    Date of Patent: May 24, 2005
    Assignee: Neomax Co., Ltd.
    Inventors: Masaaki Aoki, Tsuyoshi Tsuzaki
  • Patent number: 6856224
    Abstract: A compact permanent magnet structure is provided to produce a uniform magnetic biasing field confined to an internal cavity of a cylindrical magnetic flux source which eliminates the drawbacks, shortcomings, limitations and difficulties associated with an elongated magic ring. The compact permanent magnet structure is composed of a cylindrical magnetic flux source with a cylindrical axis, a hollow central cavity, an inner diameter and a remanence perpendicular to said cylindrical axis. The ends of the cylindrical magnetic flux source are capped by a first magnetic flux source and a second magnetic flux source. The compact permanent magnet structure produces a uniform biasing field by capping the end of the cylindrical magnetic flux source with a hemispheric section of a magic sphere having a cavity diameter and shell axis equivalent to the magic ring. The cylindrical magnetic flux source can be a magic ring and the caps can either be geometric or parametric.
    Type: Grant
    Filed: August 4, 2004
    Date of Patent: February 15, 2005
    Assignee: The United States of America as represented by the Secretary of the Army
    Inventor: Herbert A. Leupold
  • Patent number: 6781495
    Abstract: A magnetic field generator comprises a pair of plate yokes opposed to each other with a space in between. Each plate yoke has a main surface on which a permanent magnet is disposed. A shielding magnet is provided each at a forward portion on an open side and at a rearward portion, of another main surface in the plate yoke. A magnetic spacer is placed between the plate yoke and the shielding magnet. When assembling, a shielding magnet is mounted on a main surface of the spacer, and then another main surface of the spacer is placed on the main surface of the plate yoke. The shielding magnet is covered by a nonmagnetic cover member. A distance not smaller than 2 mm is provided between an outer surface of the cover member and a surface of the shielding magnet. The plate yoke is provided with nonmagnetic legs.
    Type: Grant
    Filed: September 4, 2002
    Date of Patent: August 24, 2004
    Assignee: Neomax Co., Ltd.
    Inventors: Masaaki Aoki, Tsuyoshi Tsuzaki
  • Patent number: 6763789
    Abstract: A system and method for increasing force density of a valve actuator particularly suited for use in actuation of intake and/or exhaust valves of an internal combustion engine include at least one electromagnet having a coil wound about a core, and an armature fixed to an armature shaft extending axially through the coil and the core, and axially movable relative thereto. The actuator includes a flux generator, such as at least one permanent magnet positioned between the coil and the armature, oriented so that magnetic flux of the generator travels in a direction opposite to magnetic flux produced by the coil through the core during coil energization to reduce saturation of the core, but in the same direction as the magnetic flux produced by the coil through the armature, to increase an attractive force between the armature and the electromagnet, resulting in an actuator with an increased force density.
    Type: Grant
    Filed: April 1, 2003
    Date of Patent: July 20, 2004
    Assignee: Ford Global Technologies, LLC
    Inventors: Feng Liang, Michael W. Degner
  • Patent number: 6707362
    Abstract: A magnetic device having an optimized geometry provides maximum beneficial physical effects of applying a magnetic field to a fluid. The device includes three relatively powerful magnets located radially about a fluid conduit approximately 60° apart from one another. One of the magnets has an opposite pole to the other two facing inwardly toward the fluid conduit. In order to shield electrical equipment near the device, additional magnetic strips are included having poles aligned opposite that of the neighboring, larger magnet. These magnetic strips not only shield nearby electrical equipment, they also serve to better focus the magnetic field.
    Type: Grant
    Filed: November 22, 2002
    Date of Patent: March 16, 2004
    Assignee: AZ Industries, Inc.
    Inventors: Les Adam, Harley Adam
  • Patent number: 6653920
    Abstract: A magnetic device includes a core received in a housing and having three or more outer peripheral surfaces and having one end received in the housing and the other end facing out of the housing. Three or more magnetic members are attached onto the outer peripheral surfaces of the core and secured to the core and the housing with fasteners. The magnetic members include one pole arranged closer to the core and the other pole distal to the core, in order to increase the magnetic field intensity, and to form a unidirectional magnetic line of force, and for allowing the magnetic device to be strongly attracted onto various objects.
    Type: Grant
    Filed: March 16, 2003
    Date of Patent: November 25, 2003
    Inventor: Ming Po Chen
  • Patent number: 6630879
    Abstract: A system for magnetically assisted surgery includes a magnetic support structure, a patient support structure and a magnet having at least four poles attached to the magnetic support structure so that the magnet provides a near-field magnetic field in an operating region of a patient supported by the patient support structure. The magnet is moveable so that the direction of the magnetic field lines in the operating region is adjustable. The magnet may include a pair of essentially semicircular half-segments permanently magnetized and joined in an extremely stable disk configuration. The magnetic field and gradient field provided by the magnet is such that movement of the disk in one plane combined with rotation of the disk is sufficient to orient the magnetic field during surgical use, thereby reducing interference to medical imaging devices needed during surgery.
    Type: Grant
    Filed: February 3, 2000
    Date of Patent: October 7, 2003
    Assignee: Stereotaxis, Inc.
    Inventors: Francis M. Creighton, IV, Rogers C. Ritter, Andrew F. Hall, Roger N. Hastings
  • Patent number: 6596163
    Abstract: A magnetic device for treating carbon based fuels by exposing the fuel piping to intense magnetic fields. The south magnetic poles are placed adjacent to the pipe and the flux lines in the pipe are increased by the use of permeable steel bars adjacent to the magnets and pipe. The device includes a flux path through a permeable housing and cover. The device can be installed around existing piping or inserted in the pipe line by pipe fittings.
    Type: Grant
    Filed: June 11, 2001
    Date of Patent: July 22, 2003
    Inventor: William Russel Parker
  • Patent number: 6576128
    Abstract: A magnet assembly includes a ring shaped magnet having a face with an inner surface that is removably attachable to a ferrous metal housing of a fluid filter. The face has a plurality of circumferentially spaced pairs of poles that concentrate the magnetic strength of the magnet on the face and form magnetic loops in the filter housing to cause any ferrous metal particles in the fluid being circulated through the filter housing to be trapped against interior walls of the filter housing.
    Type: Grant
    Filed: October 12, 2001
    Date of Patent: June 10, 2003
    Inventor: Otto V. Jackson
  • Patent number: 6572778
    Abstract: The method includes placing a vessel containing a solution having magnetized substances into a magnetic device. The solution is then incubated in the device for a period of time sufficient to allow the magnetized substances to migrate radially toward the interior wall of the vessel, and a sample of the solution removed from the center of the vessel would contain non-magnetized particles. The magnetic device is made of four polar magnets and a plurality of interpolar magnets disposed therebetween. The interpolar magnets are positioned to progressively rotate towards the orientation of the four polar magnets creating an even flux within the solution thereby causing the radial movement of the magnetized substances toward the inner wall of the surrounding magnets.
    Type: Grant
    Filed: September 13, 2002
    Date of Patent: June 3, 2003
    Assignee: Dexter Magnetic Technologies, Inc.
    Inventors: Martin D. Sterman, Paul Lituri, Richard E. Stelter
  • Publication number: 20020196116
    Abstract: A compact portable transport unit for shipping hyperpolarized noble gases and shielding same from electromagnetic interference and/or external magnetic fields includes a means for shifting the resonance frequency of the hyperpolarized gas outside the bandwidth of typical frequencies associated with prevalent time-dependent fields produced by electrical sources. Preferably the transport unit includes a magnetic holding field which is generated from a solenoid in the transport unit. The solenoid includes a plurality of coil segments and is sized and configured to receive the gas chamber of a container. The gas container is configured with a valve, a spherical body, and an extending capillary stem between the valve and the body. The gas container or hyperpolarized product container can also be formed as a resilient bag.
    Type: Application
    Filed: July 10, 2002
    Publication date: December 26, 2002
    Inventors: Kenton C. Hasson, Geri T.K. Zollinger, David L. Zollinger, Paul L. Bogorad, Bradley A. Wheeler
  • Publication number: 20020097122
    Abstract: Apparatus and methods for the adjustment of a magnetic field produced by permanent magnet arrangements facing each other across an air gap include a series of ferromagnetic shim blocks individually adjustably positionable within the magnet arrangements to adjust the strength and uniformity of the magnetic field. A backing plate to which the permanent magnets are attached has channels within which adjusting elements are used to move the shim blocks with relation to the permanent magnets, preferably toward or away from the air gap. Shim blocks are arrange in selected geometric arrays and shapes responsive to the geometry of the magnet arrangements and may be formed as toroidal shapes or as individual blocks of varying sizes.
    Type: Application
    Filed: January 25, 2001
    Publication date: July 25, 2002
    Inventor: Uri Rapoport
  • Patent number: 6261450
    Abstract: The present invention of a magnetic source and condenser is applied directly outside on a pipe. The magnetic device comprises a series of iron pieces having curved contact surfaces on the same side, a magnet is placed between every two piece of iron, the magnets with faces closed to one another have the same pole, thus strong magnetic force is generated by the repelling of the same pole of the two magnets, the series of iron pieces and the magnets are surrounded a frame on their sides to fix and protect the magnets from outside factors.
    Type: Grant
    Filed: November 23, 1999
    Date of Patent: July 17, 2001
    Inventor: Hai-Kun Yeh
  • Patent number: 6084491
    Abstract: In the preferred embodiment, a variable magnetic reluctor structure comprng an iron yoke having two opposing "U"-shaped bodies, magnetic flux sources formed by portions of the yoke, a magnetic flux path, a working space and a reluctor space is provided. A reluctor member comprising diamagnetic disks is inserted within the reluctor space decreasing the magnetic permeability of the magnetic flux path to a value lesser than that of air (1.0). The iron disks increase permeability, while either a Type I or a Type II superconducting disk or a combination of iron disks interspersed between Type II superconducting disks decreases permeability.
    Type: Grant
    Filed: March 4, 1999
    Date of Patent: July 4, 2000
    Assignee: The United States of America as represented by the Secretary of the Army
    Inventor: Herbert A. Leupold
  • Patent number: 6057656
    Abstract: Disclosed is a novel composite magnet assembly for an insertion device of the Halbach type or hybrid type to be inserted into the linear part of, for example, an electron accelerator to generate a sine-curved periodical magnetic field in the air gap between two oppositely facing composite magnet block arrays. Different from a conventional magnet block assembly consisting of a plurality of permanent magnet blocks or alternate assembly of permanent magnet blocks and soft-magnetic pole pieces, the inventive magnet block assembly is composed of a plurality of oppositely facing composite magnet blocks each formed with a single base magnet block provided with a plurality of slits into which insert magnet pieces or insert pole pieces are inserted so that the dimensional accuracy in the length-wise direction of the magnet block assembly can be greatly decreased to improve the regularity of the periodical magnetic field.
    Type: Grant
    Filed: April 13, 1998
    Date of Patent: May 2, 2000
    Assignees: Shin-Etsu Chemical Ci., Ltd., Kawasaki Jukogyo Kabushiki Kaisha
    Inventors: Ken Ohashi, Masayuki Kawai
  • Patent number: 5976369
    Abstract: Biological assay systems often involve suspending magnetically attractable particles in a liquid, and later bringing down the particles from suspension and separating the formed pellet from the supernatant liquid. The invention provides magnetic systems for this purpose, shaped to form an annular or part-annular pellet close to the bottom of the vessel. The systems are suitable for automation.
    Type: Grant
    Filed: April 2, 1998
    Date of Patent: November 2, 1999
    Assignee: Amersham International plc
    Inventors: Roland Paul Howe, Michael Alan Reeve, Daniel Bischof
  • Patent number: 5798680
    Abstract: Strapped open magnetic structure, particularly useful in nuclear magnetic resonance imaging applications, which provides a substantially uniform magnetic field within a region of interest while allowing access by a surgeon to a patient via an opening at the top of the magnetic structure. The magnetic structure comprises nested inner and outer magnetic structures separated by ferromagnetic material or pole pieces and surrounded by a ferromagnetic yoke. The structure contains one or more thin layers or straps of high magnetic permeability material aligned substantially along equipotential surface(s) of an associated closed magnetic structure of ideal properties.
    Type: Grant
    Filed: February 26, 1996
    Date of Patent: August 25, 1998
    Assignee: New York University
    Inventors: Manlio G. Abele, Henry Rusinek, Jens Jensen
  • Patent number: 5783981
    Abstract: The magnetic states of MR reproducing heads are reinitialized during media drive manufacturing by applying initializing magnetic fields to the transducers after they have been manufactured and incorporated into media drive assemblies.
    Type: Grant
    Filed: June 5, 1995
    Date of Patent: July 21, 1998
    Assignee: International Business Machines Corporation
    Inventors: Samir Elias Abboud, Nickolas Christopher Apuzzo, Jeffrey Bernard Brown, Earl Albert Cunningham, David Malcolm Hannon, Raymond Patrick Mallette, Paul Sheldon Tyler, Steven Harry Voss, Albert John Wallash
  • Patent number: 5716520
    Abstract: A magnetic flux fluid treating device for minimizing the discharge of hydrocarbons from internal combustion engines, eradicating scale and inhibiting its formation in water conduits and water handling equipment is formed by a coaxial soft iron tubular assembly connected with the units containing the fluid to be treated. Magnetic flux field generating units are interposed in the annuli formed by the tubular members and define lateral limits of the annuli fluid passageways. The flux field forms a south monopole and a north monopole of the innermost and outermost tubes of the assembly and a repelling force flux field in the passageways and fluid normal to the direction of flow and the coaxes of the tube assembly.
    Type: Grant
    Filed: August 20, 1996
    Date of Patent: February 10, 1998
    Inventor: Elmer B. Mason
  • Patent number: 5596304
    Abstract: Planar permanent magnet edge-field quadrupoles for use in particle accelerating machines and in insertion devices designed to generate spontaneous or coherent radiation from moving charged particles are disclosed. The invention comprises four magnetized rectangular pieces of permanent magnet material with substantially similar dimensions arranged into two planar arrays situated to generate a field with a substantially dominant quadrupole component in regions close to the device axis.
    Type: Grant
    Filed: March 29, 1994
    Date of Patent: January 21, 1997
    Assignee: The Board of Trustees of the Leland Stanford Junior University
    Inventor: Roman O. Tatchyn
  • Patent number: 5557205
    Abstract: In a magnetic field generating apparatus for use in MRI comprising cylindrical yokes, a pair of permanent magnets of a trapezoidal section opposed in parallel with each other in the cylindrical yokes with a predetermined gap being defined between each of the pole faces of them, permanent magnets of a triangular section in adjacent with both sides of the trapezoidal permanent magnet in which a magnetic field space having a hexagonal cross section in perpendicular to the longitudinal direction defined by pole faces of the trapezoidal permanent magnets and the pole faces of the triangular permanent magnets, whereinthe trapezoidal permanent magnets comprise rare earth system permanent magnet and the direction of magnetization thereof is identical with the direction of the magnetic field in the magnetic field space, the triangular permanent magnets comprise a ferrite system permanent magnet and the direction of magnetization thereof is at a 90.degree.
    Type: Grant
    Filed: December 8, 1994
    Date of Patent: September 17, 1996
    Assignee: Sumitomo Special Metals Co., Ltd.
    Inventors: Kimiharu Ohta, Masaaki Aoki
  • Patent number: 5515020
    Abstract: A premagnetizing head for charging the magnetizable pigment of characters printed on a document includes a permanent magnet (10) whose one pole is connected to a magnetically conductive metal plate (12) which extends away from the magnet (10) in a direction generally transversal to the north-south pole axis of the magnet and up to the document (D) whose characters are to be magnetized and read. The permanent magnet (10) is oriented so that its northpole-southpole axis will extend generally parallel with the plane of the document (D) to be read.
    Type: Grant
    Filed: May 12, 1993
    Date of Patent: May 7, 1996
    Assignee: ICL Systems Aktiebolag
    Inventor: Allan Stiernspetz
  • Patent number: 5506558
    Abstract: A unipolar magnet is composed of a plurality of magnetic units. Each magnetic unit is made up of a magnetic body, a paramagnetic or diamagnetic first layer which covers the entire magnetic body except for one of the poles, and a magnetically conductive second layer overlying the first layer. The exposed poles of all the magnetic units have the same polarity and together define a peripheral surface of the magnet. The magnetic units can have the configuration of a segment of a ring and can be assembled to form an annular first magnet whose external peripheral surface is constituted by the exposed poles. Several of these annular first magnets can be superimposed to form a hollow cylinder, and such a cylinder can be used to construct a shaft capable of floating in a housing. To this end, the housing is provided with annular second magnets which surround the first magnets.
    Type: Grant
    Filed: May 4, 1994
    Date of Patent: April 9, 1996
    Inventor: Hans-Jurgen Laube
  • Patent number: 5502425
    Abstract: A magnetic energy reinforcing device including a base having an axial through hole and a plurality of chambers symmetrically spaced around said through hole, a plurality of magnets respectively mounted in each chamber on the base, and a plurality of antimagnetic plates mounted on the base and respectively disposed adjacent to the magnets at an outer side to concentrate the magnetic energy of the magnets into the axial through hole.
    Type: Grant
    Filed: June 1, 1995
    Date of Patent: March 26, 1996
    Inventor: Tsung C. Tsai
  • Patent number: 5488342
    Abstract: A magnet assembly comprises a pair of substantially aligned, spaced apart first magnets (1,2) having like poles facing each other. A second magnet (3) is positioned adjacent the space between the first magnets with its magnetic axis transverse to the alignment axis of the first magnets (1,2). A magnetic field of sufficient homogeneity to perform a nuclear magnetic resonance process is generated in a working region.
    Type: Grant
    Filed: October 12, 1994
    Date of Patent: January 30, 1996
    Assignee: Oxford Instruments Limited
    Inventor: Peter Hanley
  • Patent number: 5475355
    Abstract: A technique is provided for improving the homogeneity of the magnetic field within a cavity disposed inside a magnetic structure that has an opening to permit convenient access to an imaging region. The technique is based upon the step of inserting layers of magnetized material between plates of high magnetic permeability material. The layers are inserted at the boundary of the cavity. The technique includes the step of (1) computing the surface charges on the plates as used to derive the distribution of the magnetostatic potential, (2) analyzing the uniformity of the magnetic field within the imaging region as effected by the opening in the magnetic structure by expanding the magnetostatic potential in a spatial harmonic series, and (3) determining the geometry and the composition of the inserted layers based on the successive elimination of increasing orders of spatial harmonics in the potential expansion within the imaging region.
    Type: Grant
    Filed: April 15, 1994
    Date of Patent: December 12, 1995
    Assignee: New York University
    Inventors: Manlio G. Abele, Henry Rusinek, Jens Jensen
  • Patent number: 5468381
    Abstract: An improved magnetic filter adapter for use with removable fluid system filters. The magnetic filter adapter of the present invention includes an adaptive filter housing removably mountable to a fluid system filter, magnet means for attracting metallic particles from the fluid flow within the filter toward the interior surface of the filter external wall, and an inner magnetic-field concentrating cup for concentrating the magnetic force of said magnet means such that the potential field strength of the magnet means is optimized.
    Type: Grant
    Filed: May 31, 1994
    Date of Patent: November 21, 1995
    Inventor: Carlton R. Williamson
  • Patent number: 5458785
    Abstract: Biological assay systems often involve suspending magnetically attractable particles in a liquid, and later bringing down the particles from suspension and separating the formed pellet from the supernatant liquid. The invention provides magnetic systems for this purpose, shaped to form an annular or part-annular pellet close to the bottom of the vessel. The systems are suitable for automation.
    Type: Grant
    Filed: September 24, 1993
    Date of Patent: October 17, 1995
    Assignee: Amersham International plc
    Inventors: Roland P. Howe, Michael A. Reeve, Daniel Bischof
  • Patent number: 5382875
    Abstract: A stray magnetic field suppression system for use in a CRT image display suppresses a stray magnetic field that emanates from the horizontal deflection coil of a beam-deflecting yoke which is energized by sawtooth waveform pulses from a horizontal oscillator. The system comprises two series-connected magnetic coil assemblies in conjunction with a capacitor and activated by the sawtooth waveform pulses. The capacitor serves to integrate the pulses, enabling the suppression system to form an effective field for suppressing a stray magnetic field when the magnetic coil assemblies are interposed in the path of the stray magnetic field on opposite sides of the yoke.
    Type: Grant
    Filed: August 10, 1992
    Date of Patent: January 17, 1995
    Assignee: Zenith Electronics Corporation
    Inventors: Wayne D. Grocki, Christopher S. DeWaal
  • Patent number: 5380430
    Abstract: A set of magnetic assemblies for treating fluids including water and liquid and gaseous fuels wherein each assembly includes a construction of permanent magnets and pole pieces arranged to optimize a "Figure of merit" number defined as the integral of the absolute value of magnetic field intensity over region occupied by the fluid. In one embodiment, each assembly includes an elongated magnet with permeable pole pieces at each end bent back toward each other to form a gap equal to one half the length of the magnet. In another arrangement, each assembly includes a permanent magnet having a pole piece leading around toward the flux surface at the other end of the magnet, adjacent to the fluid carrier. Dimensions of the area of the pole end surface are selected based on the permeability of the pole piece, magnetization intensity of the permanent magnet material and pipe diameter to maximize the Figure of merit. Figure of merit is maximized by placing an odd number of assemblies around the conduit.
    Type: Grant
    Filed: December 13, 1993
    Date of Patent: January 10, 1995
    Inventors: James M. Overton, Stephen R. Wurzburger
  • Patent number: 5366623
    Abstract: A magnetic well tubing and pipe protector/fluid ionizer for protecting the interior of pipes from scaling, corrosion, and algae, comprising a case (14) containing four magnetic condensers comprised of rectangular neodymium iron boron magnets (10 . . . ) and tapered concentrators (11 . . . ) which drive magnetic flux through a core (13) into flowing oil, water, or other fluids, ionizing and charging the fluid positive and the core (13) and all connected pumps and tubing negative. The flowing oil or water or other fluid cutting the perpendicular lines of magnetic flux (16) generates an electrical current which charges the pump and tubing or pipe negative enough to repel and prevent scaling, corrosion, and algaes. Also, the electrical current ionizes the oil, water or other fluids, improving separation of crude oil from water and contaminants. improving combustion of petroleum fuels, and increasing the heat transfer coefficient of heating and cooling water.
    Type: Grant
    Filed: September 11, 1992
    Date of Patent: November 22, 1994
    Inventor: Colonel Clair
  • Patent number: 5356534
    Abstract: An improved magnetic-field amplifier (10) consisting of a magnetic amplifying assembly (12) that generates a pair of magnetic loops (A), (B) that are summed at two ferromagnetic pole members (20), (22) to produce a composite magnetic field. The magnetic amplifying assembly (12) is disclosed in two configurations: an externally mounted unit and an annular, in-line mounted unit. Either the externally or annular in-line mounted units may be attached to a fluid conduit (60) to remove contaminants from the fluid. A form of the externally mounted unit may also be attached circumferentially to a motor or generator housing from where the composite magnetic field is used to operate the armature (33). The magnetic amplifying assembly is also adaptable to other magnetically operated devices that can benefit from an increased magnetic field.
    Type: Grant
    Filed: July 24, 1992
    Date of Patent: October 18, 1994
    Inventors: George M. Zimmerman, deceased, by Patricia W. Zimmerman, legal representative
  • Patent number: 5314625
    Abstract: The external oil pan magnet (10) is placed on the external surface of the oil pan (2) where it attracts and captures metallic particles suspended in a motor's oil supply. In a first embodiment, the external oil pan magnet (10) is comprised of magnet (12) coupled to a channeled shield (14). The shield (14) leaves at least one surface of the magnet exposed and amplifies the magnetic force of the magnet. The exposed surface magnetically attaches to the external surface of the oil pan (2). After the oil is drained during normal maintenance, the operator slides the magnet assembly across the bottom of the pan and over the oil pan plug hole. Metallic debris is evacuated through the oil pan plug hole. The plug is replaced and the oil supply replenished. In a second embodiment, the magnet assembly is configured to encircle the oil pan plug. The magnet temporarily magnetizes the plug which attracts metallic debris from the oil.
    Type: Grant
    Filed: December 29, 1992
    Date of Patent: May 24, 1994
    Inventor: Michael Farnelli
  • Patent number: 5278534
    Abstract: A magnetic structure defining a cavity includes a first member of high-permeability material having a flat surface defining a first wall of the cavity, and a member of permanent magnetic material spaced from the flat surface and producing a uniform magnetic field in the cavity. The permanent magnetic material member may have two or more layers, with the layers outward of the cavity being of a material having a remanence that is no greater than the adjacent inner layers.
    Type: Grant
    Filed: September 1, 1992
    Date of Patent: January 11, 1994
    Assignee: New York University
    Inventors: Manlio G. Abele, Henry Rusinek
  • Patent number: 5276419
    Abstract: A device to guide, shape, contain, or concentrate magnetic flux comprises a tube or conduit made of superconducting material to constrain the path of magnetic flux and guide it to a target volume. Below the transition point the material exhibits no resistance to electrical current flow and is impermeable to magnetic flux. In one embodiment, the superconducting material is configured into a cylindrical tube. Upon entrance into the tube the magnetic flux generated by a magnet is constrained to remain between the walls of the tube until it exits the open end where the flux passes through a target volume. In another embodiment, the magnet is situated between two hollow U-shaped arms of superconducting material. The target is situated between the opposite arms of the superconducting material. Magnetic flux generated by the magnet is confined within the U-shaped arms of the superconducting material and passes through the target volume.
    Type: Grant
    Filed: February 18, 1992
    Date of Patent: January 4, 1994
    Assignee: The United States of America as represented by the Secretary of the Air Force
    Inventors: Joseph T. Griffin, Steven M. Iden
  • Patent number: 5269916
    Abstract: A magnetic pipe protector for protecting the interior of pipes from scaling, corrosion, and algae, comprises a flat, square neodymium iron boron magnet (10) having a concentrator (11) on its lower side for attachment to a steel pipe (14). A partially cylindrical joinder piece (12) is attached to the other side of the magnet. A cylindrical pole piece (15) with a partially cylindrical cut (18) is circumferentially spaced from the concentrator on the pipe. A connector (16) has partially cylindrical grooves (17) near its distal ends for accepting the joinder piece and the pole piece. The pole piece and the joinder piece, and thus the magnet and the concentrator, may be axially rotated within the grooves to allow the pipe protector to fit pipes of various sizes. The pipe protector projects a strong magnetic field into the interior of the pipe, completely perpendicular to the direction of the water flow (F).
    Type: Grant
    Filed: September 11, 1992
    Date of Patent: December 14, 1993
    Inventor: Colonel Clair
  • Patent number: 5269915
    Abstract: A magnetic source and condenser for creating magnetic flux within a ferrous pipe (P) comprises a rectangular magnet (M) having a pair of opposing major faces and a pair of pole pieces (N and S) sandwiching the magnet. The pole pieces each have a foot (Nf and Sf) extending under the magnet and adjacent the pipe. By virtue of the pole pieces and the feet, the magnetic flux from the magnet is condensed before it is applied to the pipe. Thus it is strong enough to exceed the flux-carrying capacity of the pipe so that it travels away from the pipe in an arc (G) inside the pipe where it cuts perpendicularly the fluid flow (F) within the pipe. The flowing fluid cutting the perpendicular lines of magnetic flux generate electrical currents and charges in the fluid, which in turn ionizes the fluid and dissolved and suspended solids in the fluid, and charges the pipe negative to protect the pipe from scale, corrosion, algae, parafinning, etc.
    Type: Grant
    Filed: April 8, 1993
    Date of Patent: December 14, 1993
    Inventor: Colonel Clair
  • Patent number: 5191308
    Abstract: This magnetostatic wave device includes a ferrimagnetic substrate like, for example, a YIG thin film. On this ferrimagnetic substrate a strip line is formed. One end of the strip line is connected to an input terminal and the other end is connented to an output terminal. A magnetic field is applied to the ferrimagnetic substrate by a magnet. In this case, the ferrimagnetic substrate is so disposed that a direction parallel to its principal plane and a direction perpendicular to its principal plane are not parallel to the direction of a line of magnetic force of the magnet.
    Type: Grant
    Filed: January 14, 1991
    Date of Patent: March 2, 1993
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Makoto Tsutsumi, Toshio Nishikawa
  • Patent number: 5162771
    Abstract: A yoked magnetic structure has a pair of spaced magnetized members defining a cavity, and an end ferromagnetic structure closing said cavity and abutting an end of the magnetized members. The end structure comprising at least a first element of triangular cross section having one side abutting an end of one of said magnetized member and a second element of triangular cross section having one side abutting the adjacent side of said cavity. The first and second elements have second sides away from the magnetized member and cavity defining at least part of an equipotential line whereby the flux density on the side of the equipotential line away from the magnetized structure is zero. A region of .mu.=.infin. material is provided adjacent the magnetized member to minimize the effect of perturbations.
    Type: Grant
    Filed: May 30, 1991
    Date of Patent: November 10, 1992
    Assignee: New York University
    Inventor: Manlio G. Abele
  • Patent number: 5128643
    Abstract: A magnetic shield is presented comprising a shell of ferromagnetic material, augmented by one or more shielding magnets. The shielding magnets may be permanent magnets, electromagnetic coils, or other sources of magnetic flux. These shielding magnets are placed in close proximity to the shell, on the surface facing the region to be shielded, and are arranged to cancel any magnetic flux penetrating through the ferromagnetic shell into the region to be shielded. This invention provides magnetic protection for an exterior region when the shield is assembled around a magnet whose external field is to be contained, such as an MRI magnet. This invention also provides protection within an interior volume which is to be protected from an exterior source such as the Earth's magnetic field. The method by which the invention is applied is an iterative one, in which the shielding magnets are applied to substantially cancel the leakage field and then adjusted to minimize the remaining field in the shielded region.
    Type: Grant
    Filed: September 24, 1990
    Date of Patent: July 7, 1992
    Inventor: David E. Newman
  • Patent number: 5126713
    Abstract: A magnetic circuit including a structure for magnetically cladding a permnt magnet solenoid to eliminate flux leakage therefrom. The cladding includes hemispherical magnetic cladding elements located at the ends of the solenoid in order to eliminate sharp end corners and thus further suppress flux leakage from the magnetic circuit.
    Type: Grant
    Filed: December 20, 1991
    Date of Patent: June 30, 1992
    Assignee: The United States of America as represented by the Secretary of the Army
    Inventor: Herbert A. Leupold