Patents by Inventor Tomoki Fukagawa

Tomoki Fukagawa has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Publication number: 20170018342
    Abstract: An R-T-B based sintered magnet has a composition represented by the following formula (1) which satisfies the following inequality expressions (2) to (9): uRwBxGazAlvCoqTigFejM??(1) (R is at least one of rare-earth elements and indispensably includes Nd, M is an element except for R, B, Ga, Al, Co, Ti, and Fe, and u, w, x, z, v, q, g, and j are expressed in terms of % by mass). 29.0?u?32.0??(2) (heavy rare-earth elements RH account for 10% by mass or less of the R-T-B based sintered magnet) 0.93?w?1.00??(3) 0.3?x?0.8??(4) 0.05?z?0.5??(5) 0?v?3.0??(6) 0.15?q?0.28??(7) 60.42?g?69.57??(8) 0?j?2.0??(9) and satisfies other requirements.
    Type: Application
    Filed: February 27, 2015
    Publication date: January 19, 2017
    Applicant: HITACHI METALS, LTD.
    Inventors: Tomoki FUKAGAWA, Noriyuki NOZAWA, Takeshi NISHIUCHI, Daisuke FURUSAWA, Shinichiroh SAKASHITA
  • Patent number: 8323806
    Abstract: A rare-earth magnet includes a magnet body made of an R—Fe—B based rare-earth magnet material (where R is at least one rare-earth element) and a metal film that has been deposited on the surface of the magnet body. The magnet further includes a plurality of reaction layers between the magnet body and the metal film. The reaction layers include: a first reaction layer, which contacts with at least some of R2Fe14B type crystals, included in the magnet body, to have received the rare-earth element that has been included in the R2Fe14B type crystals; and a second reaction layer, which is located between the first reaction layer and the metal film and which has a lower rare-earth element concentration than that of the first reaction layer.
    Type: Grant
    Filed: December 11, 2009
    Date of Patent: December 4, 2012
    Assignee: Hitachi Metals, Ltd.
    Inventor: Tomoki Fukagawa
  • Publication number: 20100092660
    Abstract: A rare-earth magnet includes a magnet body made of an R—Fe—B based rare-earth magnet material (where R is at least one rare-earth element) and a metal film that has been deposited on the surface of the magnet body. The magnet further includes a plurality of reaction layers between the magnet body and the metal film. The reaction layers include: a first reaction layer, which contacts with at least some of R2Fe14B type crystals, included in the magnet body, to have received the rare-earth element that has been included in the R2Fe14B type crystals; and a second reaction layer, which is located between the first reaction layer and the metal film and which has a lower rare-earth element concentration than that of the first reaction layer.
    Type: Application
    Filed: December 11, 2009
    Publication date: April 15, 2010
    Applicant: HITACHI METALS, LTD.
    Inventor: Tomoki FUKAGAWA
  • Patent number: 7655325
    Abstract: A rare-earth magnet includes a magnet body made of an R—Fe—B based rare-earth magnet material (where R is at least one rare-earth element) and a metal film that has been deposited on the surface of the magnet body. The magnet further includes a plurality of reaction layers between the magnet body and the metal film. The reaction layers include: a first reaction layer, which contacts with at least some of R2Fe14B type crystals, included in the magnet body, to have received the rare-earth element that has been included in the R2Fe14B type crystals; and a second reaction layer, which is located between the first reaction layer and the metal film and which has a lower rare-earth element concentration than that of the first reaction layer.
    Type: Grant
    Filed: June 25, 2008
    Date of Patent: February 2, 2010
    Assignee: Hitachi Metals, Ltd.
    Inventor: Tomoki Fukagawa
  • Publication number: 20080254285
    Abstract: A rare-earth magnet includes a magnet body made of an R—Fe—B based rare-earth magnet material (where R is at least one rare-earth element) and a metal film that has been deposited on the surface of the magnet body. The magnet further includes a plurality of reaction layers between the magnet body and the metal film. The reaction layers include: a first reaction layer, which contacts with at least some of R2Fe14B type crystals, included in the magnet body, to have received the rare-earth element that has been included in the R2Fe14B type crystals; and a second reaction layer, which is located between the first reaction layer and the metal film and which has a lower rare-earth element concentration than that of the first reaction layer.
    Type: Application
    Filed: June 25, 2008
    Publication date: October 16, 2008
    Applicant: HITACHI METALS, LTD.
    Inventor: Tomoki FUKAGAWA
  • Patent number: 7046490
    Abstract: A spin valve magnetoresistance sensor of a thin film magnetic head. In one embodiment, a spin valve magnetoresistance sensor is provided with a spin valve film, in which a base layer including a first base film of Ta or some other nonmagnetic metal and, on top of this, a second base film of an alloy represented by NiFeX (where X is at least one element selected from among Cr, Nb, Rh) is formed on a substrate, and on top of this are formed by layering a free magnetic layer and pinned magnetic layer arranged to enclose a nonmagnetic conductive layer, as well as an antiferromagnetic layer, the second base film has an fcc (face-centered cubic) structure and also has a (111) orientation.
    Type: Grant
    Filed: January 6, 2000
    Date of Patent: May 16, 2006
    Assignee: Western Digital (Fremont), Inc.
    Inventors: Masaki Ueno, Hideyasu Nagai, Koichi Suzuki, Tomoki Fukagawa, Fuminori Hikami
  • Patent number: 6777362
    Abstract: A dielectric ceramic composition wherein the dielectric constant ∈ is large, the temperature coefficient &tgr;f of the resonance frequency is close to 0, and which as a large Q value, is obtained by adding to and blending with a ceramic composition whose &tgr;f of the resonance frequency is large on the plus side a ceramic composition whose temperature coefficient &tgr;f is large on the minus side. In an Li2O—R2O3—TiO2-based composition, an improved dielectric constant ∈ can be achieved by introducing a specific quantity of Bi2O3, and &tgr;f can be shifted to the plus side and in addition a considerable improvement in Qf achieved by introducing a specific quantity of MO, where M is one or two of Ca and Sr. Furthermore, by introducing a specific quantity of Na2O together with the MO (where M is one or two of CA and Sr), in particular in the case of material of ∈r>150, it is possible to control &tgr;f to the vicinity of 0 while maintaining Qf at an high value.
    Type: Grant
    Filed: October 21, 2002
    Date of Patent: August 17, 2004
    Assignee: Sumitomo Special Metals Co., Ltd.
    Inventors: Tomoki Fukagawa, Kazuhiro Nishikawa
  • Patent number: 6636394
    Abstract: A spin-valve magnetic resistance sensor. In one embodiment, the spin-valve magnetic resistance sensor includes a pair of ferromagnetic layers with a non-magnetic layer sandwiched in between. The pair of ferromagnetic layers, the non-magnetic layer and an antiferromagnetic layer are laminated on a substrate. The antiferromagnetic layer is formed using an antiferromagnetic material which uses a Pt—Mn—X alloy, Ir—Mn—X alloy, Rh—Mn—X alloy, Ru—Mn—X alloy or Pd—Mn—X alloy. X indicates one or more elements selected from a set consisting of elements of groups IIA, IVA, VA, IIIB and IVB of the periodic table. X is in the range of 0.1 at % to 15 at %.
    Type: Grant
    Filed: February 23, 2000
    Date of Patent: October 21, 2003
    Assignee: Read-Rite SMI Corp.
    Inventors: Tomoki Fukagawa, Hiroshi Nishida, Masateru Nose, Fuminori Hikami
  • Publication number: 20030100437
    Abstract: An object of the present invention is to obtain a dielectric ceramic composition wherein the dielectric constant ∈ is large, the temperature coefficient &tgr;f of the resonance frequency is close to 0, and which has a large Q value, by adding to and blending with a ceramic composition whose &tgr;f of the resonance frequency is large on the plus side a ceramic composition whose temperature coefficient &tgr;f is large on the minus side. In an Li2O—R2O3—TiO2-based composition, an improved dielectric constant ∈ can be achieved by introducing a specific quantity of Bi2O3, and &tgr;f can be shifted to the plus side and in addition a considerable improvement in Qf achieved by introducing a specific quantity of MO (where M is one or two of Ca and Sr).
    Type: Application
    Filed: October 21, 2002
    Publication date: May 29, 2003
    Inventors: Tomoki Fukagawa, Kazuhiro Nishikawa
  • Patent number: 6322911
    Abstract: The present invention provides a spin-valve magnetic resistance sensor in which an underlayer, which has a second underlayer film with an fcc structure consisting of an alloy formed by combining one or more elements selected from a set consisting of elements of group VIIIa and group Ib of the periodic table, and one or more elements selected from a set consisting of elements of groups IIa, IVa, Va, VIa, IIb, Ib and IVb of the periodic table, such as NiFeCrTi or NiCrTi, etc., is formed on the substrate, and a magnetic resistance (MR) film which has an antiferromagnetic layer consisting of a Pt1−xMnx alloy or an Ir1−xMnx alloy is laminated on top of this underlayer. The composition ratio of the element with the smallest free energy of oxide formation among the elements contained in the alloy of the second underlayer film is in the range of 0.1 atomic % to 15 atomic %.
    Type: Grant
    Filed: February 1, 2000
    Date of Patent: November 27, 2001
    Assignee: Read-Rite Corporation
    Inventors: Tomoki Fukagawa, Hiroshi Nishida, Masanori Ueno, Masateru Nose, Hideyasu Nagai, Fuminori Higami
  • Patent number: 5470529
    Abstract: A high tensile strength, hot or cold rolled steel sheet having improved ductility and hole expandability consists essentially, on a weight basis, of: C: 0.05-0.3%, Si: 2.5% or less, Mn: 0.05-4%, Al: greater than 0.10% and not greater than 2.0% wherein 0.5.ltoreq.Si(%)+Al(%).ltoreq.3.0, optionally one or more of Cu, Ni, Cr, Ca, Zr, rare earth metals (REM), Nb, Ti, and V, and a balance of Fe and inevitable impurites with N being limited to 0.01% or less. The steel sheet has a structure comprising at least 5% by volume of retained austenite in ferrite or in ferrite and bainite. A hot rolled steel sheet is produced by hot rolling with a finish rolling end temperature in the range of 780.degree.-840.degree. C., cooling to a coiling temperature in the range of 300.degree.-450.degree. C. either by rapid cooling to the coiling temperature at a rate of 10.degree.-50.degree. C./sec or by initial rapid cooling to a temperature range of 600.degree.-700.degree. C.
    Type: Grant
    Filed: March 8, 1994
    Date of Patent: November 28, 1995
    Assignee: Sumitomo Metal Industries, Ltd.
    Inventors: Shigeki Nomura, Nozomi Komatsubara, Naomitsu Mizui, Kazutoshi Kunishige, Tomoki Fukagawa