Patents Examined by John P Sheehan
  • Patent number: 8329056
    Abstract: Anisotropic rare earth-iron based resin bonded magnet comprises: [1] a continuous phase including: (1) a spherical Sm2Fe17N3 based magnetic material covered with epoxy oligomer where its average particle size is 1 to 10 ?m, its average aspect ratio ARave is 0.8 or more, and mechanical milling is not applied after Sm—Fe alloy is nitrided; (2) a linear polymer with active hydrogen group reacting to the oligomer; and (3) additive; and [2] a discontinuous phase being an Nd2Fe14B based magnetic material coated with the epoxy oligomer where its average particle size is 50 to 150 ?m, and its average aspect ratio ARave is 0.65 or more, further satisfying: [3] the air-gap ratio of a granular compound on the phases is 5% or less; and [4] a composition where crosslinking agent with 10 ?m or less is adhered on the granular compound is formed at 50 MPa or less.
    Type: Grant
    Filed: August 10, 2010
    Date of Patent: December 11, 2012
    Assignee: Minebea Co., Ltd.
    Inventors: Fumitoshi Yamashita, Osamu Yamada, Shiho Ohya
  • Patent number: 8157929
    Abstract: Disclosed are: a magnetic shielding material having excellent magnetic shielding property at a low magnetic field; and a magnetic shielding component and a magnetic shielding room each using the magnetic shielding material. Specifically disclosed is a magnetic shielding material comprising the following components (by mass): Ni: 70.0-85.0%, Cu: 0.6% or less, Mo: 10.0% or less and Mn: 2.0% or less, with the remainder being substantially Fe. The magnetic shielding material has a relative magnetic permeability of 40,000 or more under a magnetic field of 0.05 A/m and a squareness ratio (Br/B0.8) of 0.85 or less, wherein the squareness ratio (Br/B0.8) is a ratio of a remanent magnetic flux density (Br) to a maximum magnetic flux density (B0.8) in a DC hysteresis curve produced under the maximum magnetic field of 0.8 A/m.
    Type: Grant
    Filed: February 12, 2008
    Date of Patent: April 17, 2012
    Assignee: Hitachi Metals, Ltd.
    Inventors: Shin-ichiro Yokoyama, Yasuyuki Ilda, Hakaru Sasaki, Yoji Ishikura, Hiromitsu Itabashi, Masahiro Mita, Yoshiyuki Fujihara
  • Patent number: 8021498
    Abstract: A magnetic core making use of an Fe-based amorphous alloy ribbon that simultaneously attains miniaturization and noise reduction through realization of high Bs; and an applied product making use of the same. There is provided a magnetic core making use of an Fe-based amorphous alloy ribbon, wherein the saturated magnetic flux density (Bs) of the Fe-based amorphous alloy ribbon is ?1.60 T and wherein the ratio between magnetic flux density at a core external magnetic field of 80 A/m (B80) and Bs of the Fe-based amorphous alloy ribbon, B80/Bs, is ?0.90.
    Type: Grant
    Filed: March 28, 2006
    Date of Patent: September 20, 2011
    Assignee: Hitachi Metals, Ltd.
    Inventors: Yuichi Ogawa, Masamu Naoe, Yoshihito Yoshizawa
  • Patent number: 8016951
    Abstract: An object of the present invention is to provide a grain-oriented electrical steel sheet with low core loss and low magnetostriction and a method for producing the same. The grain-oriented electrical steel sheet is excellent in reduced core loss and magnetostriction while under a high flux density of 1.9 T, comprises a refined magnetic domain comprising a laser irradiated portion which has melted and resolidified to form a solidified layer, wherein the thickness of the solidified layer is 4 ?m or less. The grain-oriented electrical steel sheet may further comprise a laser irradiated portion where a surface roughness Rz is small and a cross section viewed from a transverse direction has a concave portion having a width of 200 ?m or less and a depth of 10 ?m or less for further improvement.
    Type: Grant
    Filed: April 26, 2006
    Date of Patent: September 13, 2011
    Assignee: Nippon Steel Corporation
    Inventors: Satoshi Arai, Hideyuki Hamamura, Tatsuhiko Sakai, Kaoru Sato, Hideyuki Kobayashi
  • Patent number: 8012270
    Abstract: A soft magnetic alloy consists essentially of 5 percent by weight?Co?30 percent by weight, 1 percent by weight?Cr?20 percent by weight, 0.1 percent by weight?Al?2 percent by weight, 0 percent by weight?Si?1.5 percent by weight, 0.017 percent by weight?Mn?0.2 percent by weight, 0.01 percent by weight?S?0.05 percent by weight where Mn/S is >1.7, 0 percent by weight?O?0.0015 percent by weight, und 0.0003 percent by weight?Ce?0.05 percent by weight, 0 percent by weight?Ca?0.005 percent by weight and the remainder iron, where 0.117 percent by weight?(Al+Si+Mn+V+Mo+W+Nb+Ti+Ni)?5 percent by weight.
    Type: Grant
    Filed: July 24, 2008
    Date of Patent: September 6, 2011
    Assignee: Vacuumschmelze GmbH & Co. KG
    Inventors: Witold Pieper, Joachim Gerster
  • Patent number: 8012269
    Abstract: A rare earth permanent magnet material is based on an R—Fe—Co—B—Al—Cu system wherein R is at least one element selected from Nd, Pr, Dy, Tb, and Ho, 15 to 33% by weight of Nd being contained. At least two compounds selected from M-B, M-B—Cu and M-C compounds (wherein M is Ti, Zr or Hf) and an R oxide have precipitated within the alloy structure as grains having an average grain size of up to 5 ?m which are uniformly distributed in the alloy structure at intervals of up to 50 ?m.
    Type: Grant
    Filed: December 23, 2005
    Date of Patent: September 6, 2011
    Assignee: Shin-Etsu Chemical Co., Ltd.
    Inventors: Kenji Yamamoto, Koichi Hirota, Takehisa Minowa
  • Patent number: 8007600
    Abstract: The invention provides a soft magnetic thin strip which contains nanoscale fine grains and exhibits a high saturation magnetic flux density and excellent soft magnetic characteristics; a process for production of the same; magnetic parts; and an amorphous thin strip to be used in the production. In the invention, an amorphous thin strip is used, which is represented by the composition formula: Fe100-x-y-zAxMyXz-aPa (wherein A is at least one element selected from between Cu and Au; M is at least one element selected from among Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W and Mn; X is at least one element selected from between B and Si; and x, y, z and a (in terms of atomic percentage) satisfy the relationships: 0.5?x?1.5, 0?y?2.5, 10?z?23, and 0.35?a?10 respectively) and permits 180° bending.
    Type: Grant
    Filed: April 24, 2008
    Date of Patent: August 30, 2011
    Assignee: Hitachi Metals, Ltd.
    Inventors: Motoki Ohta, Yoshihito Yoshizawa
  • Patent number: 7998284
    Abstract: Grain-oriented electrical steel sheet having a chrome-free high tensile strength insulating film characterized by comprising steel sheet on the surface of which is formed an insulating film containing a phosphate and colloidal silica as main ingredients and containing crystalline magnesium phosphate uniformly dispersed over the entire surface.
    Type: Grant
    Filed: May 18, 2007
    Date of Patent: August 16, 2011
    Assignee: Nippon Steel Corporation
    Inventors: Kazutoshi Takeda, Fumiaki Takahashi, Shuichi Yamazaki, Hiroyasu Fujii, Fumikazu Andou
  • Patent number: 7998283
    Abstract: The disclosure provides a rare earth anisotropic hard magnetic material, which has, on atomic percent basis, a composition of (Sm1-?R?)xFe100-x-y-zMyIz, wherein, R is Pr alone or a combination of Pr with at least one rare earth element selected from the group consisting of La, Ce, Nd, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu and Y; M is at least one element selected from the group consisting of Si, Ti, V, Cr, Mn, Co, Ni, Cu, Zn, Nb, Mo, Al, and Zr; I is N alone or a combination of N and C; 0.01???0.30; 7?x?12, 0.01?y?8.0, 6?z?14.4, and which anisotropic rare earth hard magnetic material is crystallized in a Th2Zn17-type structure, of which crystalline grains are in a flake shape with a gain size ranging from 1 to 5 ?m, and c-axis of the crystalline grains, an easy magnetization direction, being oriented along the minor axis of the flake crystalline grains.
    Type: Grant
    Filed: April 13, 2007
    Date of Patent: August 16, 2011
    Inventor: Yingchang Yang
  • Patent number: 7988795
    Abstract: An R-T-B—C rare earth sintered magnet (R?Ce, Pr, Nd, Tb, or Dy; T=Fe) is obtained by mixing an R-T-B—C magnet matrix alloy with an R fluoride and an R-rich R-T-B—C sintering aid alloy, followed by pulverization, compaction and sintering. The sintered structure consists of an R2T14B type crystal primary phase and a grain boundary phase. The grain boundary phase consists essentially of 40-98 vol % of R—O1-x—F1+2x and/or R—Fy, 1-50 vol % of R—O, R—O—C or R—C compound phase, 0.05-10 vol % of R-T phase, 0.05-20 vol % of B-rich phase or M-B2 phase (M=Ti, V, Cr, Zr, Nb, Mo, Hf, Ta or W), and the balance of an R-rich phase.
    Type: Grant
    Filed: November 30, 2006
    Date of Patent: August 2, 2011
    Assignee: Shin-Etsu Chemical Co., Ltd.
    Inventors: Koichi Hirota, Takehisa Minowa
  • Patent number: 7988798
    Abstract: The present invention provides an amorphous alloy ribbon superior in magnetic characteristics and lamination factor by defining the slip property of the amorphous alloy ribbon surface in a specific range, that is, an amorphous alloy ribbon superior in magnetic characteristics and lamination factor produced by the single roll method, characterized in that the slip property of the ribbon surface satisfies the following equation: 0.1?F=P/M?1.0 where, F is the slip friction coefficient, P is the force pulling the intermediate part of the amorphous ribbon when applying weight from above to three amorphous ribbons stacked together, and M is the load applied from the top of the amorphous ribbon (5 kg).
    Type: Grant
    Filed: February 14, 2007
    Date of Patent: August 2, 2011
    Assignee: Nippon Steel Corporation
    Inventors: Shigekatsu Ozaki, Takeshi Imai
  • Patent number: 7988797
    Abstract: A nanocomposite magnet according to the present invention has a composition represented by the general formula: RxQyMz(Fe1-mTm)bal, where R is at least one rare-earth element, Q is at least one element selected from the group consisting of B and C, M is at least one metal element that is selected from the group consisting of Al, Si, Ti, V, Cr, Mn, Cu, Zn, Ga, Zr, Nb, Mo, Ag, Hf, Ta, W, Pt, Au and Pb and that always includes Ti, and T is at least one element selected from the group consisting of Co and Ni. The mole fractions x, y, z and m satisfy the inequalities of 6 at %?x<10 at %, 10 at %?y?17 at %, 0.5 at %?z?6 at % and 0?m?0.5, respectively. The nanocomposite magnet includes a hard magnetic phase and a soft magnetic phase that are magnetically coupled together. The hard magnetic phase is made of an R2Fe14B-type compound, and the soft magnetic phase includes an ?-Fe phase and a crystalline phase with a Curie temperature of 610° C. to 700° C. (? phase) as its main phases.
    Type: Grant
    Filed: May 17, 2010
    Date of Patent: August 2, 2011
    Assignee: Hitachi Metals, Ltd.
    Inventors: Yasutaka Shigemoto, Satoshi Hirosawa, Toshio Miyoshi
  • Patent number: 7985303
    Abstract: A rare earth permanent magnet is prepared by disposing a powdered metal alloy containing at least 70 vol % of an intermetallic compound phase on a sintered body of R—Fe—B system, and heating the sintered body having the powder disposed on its surface below the sintering temperature of the sintered body in vacuum or in an inert gas for diffusion treatment. The advantages include efficient productivity, excellent magnetic performance, a minimal or zero amount of Tb or Dy used, an increased coercive force, and a minimized decline of remanence.
    Type: Grant
    Filed: October 27, 2010
    Date of Patent: July 26, 2011
    Assignee: Shin-Etsu Chemical Co., Ltd.
    Inventors: Hiroaki Nagata, Tadao Nomura, Takehisa Minowa
  • Patent number: 7981223
    Abstract: The present invention is a grain-oriented electrical steel sheet characterized in that Bi is present at 0.01 to less than 1,000 ppm in terms of mass at the interface of the substrate steel and the primary film of the grain-oriented electrical steel sheet. The grain-oriented electrical steel sheet is produced by any of the processes of: before decarburization annealing, applying preliminary annealing for 1 to 20 sec. at 700° C. or higher and controlling an atmosphere in the temperature range; controlling the maximum attaining temperature B (° C.) before final cold rolling so that the maximum attaining temperature B may satisfy the expression, ?10×ln(A)+1,100?B?10×ln(A)+1,220, in accordance with a Bi content A (ppm) and at the same time heating the steel sheet cold rolled to the final thickness to 700° C. or higher within 10 sec. or at a heating rate of 100° C./sec. or more before decarburization annealing, or immediately thereafter applying preliminary annealing for 1 to 20 sec. at 700° C.
    Type: Grant
    Filed: June 27, 2008
    Date of Patent: July 19, 2011
    Assignee: Nippon Steel Corporation
    Inventors: Eiichi Nanba, Katsuyuki Yanagihara, Satoshi Arai, Shuichi Yamazaki, Fumikazu Ando, Kazutoshi Takeda, Yousuke Kurosaki, Nobuo Tachibana
  • Patent number: 7976643
    Abstract: A nanocomposite magnet containing an Fe particle in the grain boundary of an Nd2Fe14B compound particle is produced by mixing a dispersion of the Nd2Fe14B compound particle in a solvent containing a surface-active agent and a dispersion of the Fe particle in a solvent containing a surface-active agent, and then supporting the Fe particle on the surface of the Nd2Fe14B compound particle by stirring the mixture of the dispersions while adding an amphiphilic solvent, and then performing the drying and the drying and the sintering.
    Type: Grant
    Filed: November 27, 2007
    Date of Patent: July 12, 2011
    Assignee: Toyota Jidosha Kabushiki Kaisha
    Inventors: Noritsugu Sakuma, Tetsuya Shoji
  • Patent number: 7976645
    Abstract: In a production of grain-oriented electrical steel sheet that is heated at a temperature of not higher than 1350° C., (a) the hot-rolled sheet is heated to a prescribed temperature of 1000° C. to 1150° C., and after recrystallization is annealed for a required time at a lower temperature of 850° C. to 1100° C., or (b) in the hot-rolled sheet annealing process decarburization is conducted to adjust the difference in the amount of carbon before and after decarburization to 0.002 to 0.02 mass %. In the temperature elevation process used in the decarburization annealing of the steel sheet, heating is conducted in the temperature range of 550° C. to 720° C. at a heating rate of at least 40° C./s, preferably 75 to 125° C./s, utilizing induction heating for the rapid heating used in the temperature elevation process in decarburization annealing.
    Type: Grant
    Filed: May 23, 2007
    Date of Patent: July 12, 2011
    Assignee: Nippon Steel Corporation
    Inventors: Yoshiyuki Ushigami, Norikazu Fujii, Tomoji Kumano
  • Patent number: 7976644
    Abstract: The present invention provides a method of production of grain-oriented electrical steel sheet comprising making a slab heating temperature 1280° C. or less, annealing hot rolled sheet by (a) a process of heating it to a predetermined temperature of 1000 to 1150° C. to cause recrystallization, then annealing by a temperature lower than that of 850 to 1100° C. or by (b) decarburizing in annealing the hot rolled sheet so that a difference in amounts of carbon of the steel sheet before and after annealing the hot rolled sheet becomes 0.002 to 0.02 mass % and performing the heating in the temperature elevation process of the decarburization annealing under conditions of a heating rate of 40° C. or more, preferably 75 to 125° C./s while the temperature of the steel sheet is in a range from 550° C. to 720° C. and utilizing induction heating for rapid heating in the temperature elevation process of decarburization annealing.
    Type: Grant
    Filed: May 22, 2007
    Date of Patent: July 12, 2011
    Assignee: Nippon Steel Corporation
    Inventors: Yoshiyuki Ushigami, Norikazu Fujii, Takeshi Kimura, Maremizu Ishibashi, Shuichi Nakamura, Koji Yamasaki
  • Patent number: 7972448
    Abstract: Disclosed herein is a method for the production of an anisotropic magnetic powder or a magnet produced from said powder, wherein a hydrogenating and dehydrogenating method is applied to the starting material in order to produce the powder. An anisotropic oriented magnetic material, more particularly magnetic scrap metal, is advantageously used as starting material so that the complicated use of a molten mass with isotropic distribution of the c axes of the hard metal crystals is not required. The result is an anisotropic material having a fine grain structure and a crystallographic orientation matching a TMXB phase formed during hydrogenation.
    Type: Grant
    Filed: November 27, 2003
    Date of Patent: July 5, 2011
    Assignee: Vacuumschmelze GmbH & Co. KG
    Inventor: Georg Werner Reppel
  • Patent number: 7967919
    Abstract: The present invention provides a method for manufacturing a self-organized rare earth-iron bonded magnet, including: a first step of covering a rare earth-iron magnet powder with oligomer or prepolymer in which one molecule includes at least two or more reactive ground substances to provide a surface-treated magnet powder; a second step of melting and kneading stretchable polymer and the surface-treated magnet powder to coarsely crush the resultant material to provide a granule; a third step of dry blending the granule with hardener to provide a compound; a fourth step of compressing the compound under temperature conditions by which the oligomer or prepolymer, the polymer, and the hardener are caused to melt and to flow to provide a green compact; a fifth step of causing the green compact to be a self-organized rare earth-iron bonded magnet by reacting the oligomer or prepolymer, and polymer with the hardener; and a sixth step of stretching the bonded magnet to transform the shape to any of a circular-shape
    Type: Grant
    Filed: May 26, 2005
    Date of Patent: June 28, 2011
    Assignee: Panasonic Corporation
    Inventor: Fumitoshi Yamashita
  • Patent number: 7964043
    Abstract: The invention relates to a method and to a device for carrying out a manufacturing process in which all magnet cores to be produced are first continuously crystallized. Depending on whether the required hysteresis loops should be round, flat or rectangular, the magnet cores are either immediately finished, that is enclosed in housings, conditioned to a rectangular hysteresis loop in a direct-axis magnetic field or to a flat hysteresis loop in a magnetic cross-field and then finished.
    Type: Grant
    Filed: June 17, 2009
    Date of Patent: June 21, 2011
    Assignee: Vacuumschmelze GmbH & Co. KG
    Inventors: Jörg Petzold, Volker Kleespies, Hans-Rainer Hilzinger