Patents by Inventor Toshio Miyoshi

Toshio Miyoshi 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).

  • Patent number: 9666361
    Abstract: A method for producing a bonded rare-earth magnet according to an embodiment of the present invention includes the steps of: providing a rapidly solidified rare-earth magnet alloy powder; providing a solution in which a resin that is in solid phase at an ordinary temperature is dissolved in an organic solvent; mulling the rapidly solidified rare-earth magnet alloy powder and the solution together and vaporizing the organic solvent, thereby making a bonded rare-earth magnet compound in which magnet powder particles that form the rapidly solidified rare-earth magnet alloy powder are coated with the resin; making a compressed compact by compressing the bonded rare-earth magnet compound under a pressure of 1000 MPa to 2500 MPa; and thermally treating the compressed compact. If the rapidly solidified rare-earth magnet alloy powder to be mulled is 100 mass %, the solution includes 0.4 mass % to 1.0 mass % of the resin and 1.2 mass % to 20 mass % of the organic solvent.
    Type: Grant
    Filed: February 27, 2012
    Date of Patent: May 30, 2017
    Assignee: HITACHI METALS, LTD.
    Inventors: Kazuhiro Takayama, Toshio Miyoshi
  • Patent number: 8961868
    Abstract: In a nanocomposite bulk magnet according to the present invention, nanocomposite magnet powder particles, including an Nd2Fe14B crystalline phase and an ?-Fe phase, are combined together. The composition of the magnet is represented by T100-x-y-z-n(B1-qCq)xRyTizMn, where T is at least one transition metal element selected from the group consisting of Fe, Co and Ni and always including Fe, R is at least one rare-earth element including substantially no La or Ce, M is an additive metallic element, and x, y, z, n and q satisfy 4 at %?x?10 at %, 6 at %?y?10 at %, 0.05 at %?z?5 at %, 0 at %?n?10 at %, and 0?q?0.5, respectively. The powder particles have a minor-axis size of less than 40 ?m. And powder particles, of which the major-axis size exceeds 53 ?m, account for at least 90 mass % of the entire magnet. And those powder particles are directly combined with each other. Consequently, a full-dense magnet, of which the density is 96% or more of the true density of its material alloy, is realized.
    Type: Grant
    Filed: March 30, 2010
    Date of Patent: February 24, 2015
    Assignee: Hitachi Metals, Ltd.
    Inventor: Toshio Miyoshi
  • Publication number: 20130323109
    Abstract: A method for producing a bonded rare-earth magnet according to an embodiment of the present invention includes the steps of: providing a rapidly solidified rare-earth magnet alloy powder; providing a solution in which a resin that is in solid phase at an ordinary temperature is dissolved in an organic solvent; mulling the rapidly solidified rare-earth magnet alloy powder and the solution together and vaporizing the organic solvent, thereby making a bonded rare-earth magnet compound in which magnet powder particles that form the rapidly solidified rare-earth magnet alloy powder are coated with the resin; making a compressed compact by compressing the bonded rare-earth magnet compound under a pressure of 1000 MPa to 2500 MPa; and thermally treating the compressed compact. If the rapidly solidified rare-earth magnet alloy powder to be mulled is 100 mass %, the solution includes 0.4 mass % to 1.0 mass % of the resin and 1.2 mass % to 20 mass % of the organic solvent.
    Type: Application
    Filed: February 27, 2012
    Publication date: December 5, 2013
    Applicant: HITACHI METALS, LTD.
    Inventors: Kazuhiro Takayama, Toshio Miyoshi
  • Publication number: 20120021221
    Abstract: In a nanocomposite bulk magnet according to the present invention, nanocomposite magnet powder particles, including an Nd2Fe14B crystalline phase and an ?-Fe phase, are combined together. The composition of the magnet is represented by T100-x-y-z-n(B1-qCq)xRyTizMn, where T is at least one transition metal element selected from the group consisting of Fe, Co and Ni and always including Fe, R is at least one rare-earth element including substantially no La or Ce, M is an additive metallic element, and x, y, z, n and q satisfy 4 at %?x?10 at %, 6 at %?y?10 at %, 0.05 at %?z?5 at %, 0 at %?n?10 at %, and 0?q?0.5, respectively. The powder particles have a minor-axis size of less than 40 ?m. And powder particles, of which the major-axis size exceeds 53 ?m, account for at least 90 mass % of the entire magnet. And those powder particles are directly combined with each other. Consequently, a full-dense magnet, of which the density is 96% or more of the true density of its material alloy, is realized.
    Type: Application
    Filed: March 30, 2010
    Publication date: January 26, 2012
    Applicant: HITACHI METALS, LTD.
    Inventor: Toshio Miyoshi
  • 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: 7938915
    Abstract: A method for producing a rare-earth alloy based binderless magnet according to the present invention includes the steps of: (A) providing a rapidly solidified rare-earth alloy magnetic powder; and (B) compressing and compacting the rapidly solidified rare-earth alloy magnetic powder by a cold process without using a resin binder, thereby obtaining a compressed compact, 70 vol % to 95 vol % of which is the rapidly solidified rare-earth alloy magnetic powder.
    Type: Grant
    Filed: August 3, 2006
    Date of Patent: May 10, 2011
    Assignees: Hitachi Metals, Ltd., Nippon Kagaku Yakin Co., Ltd.
    Inventors: Hirokazu Kanekiyo, Toshio Miyoshi, Katsunori Bekki, Ikuo Uemoto, Kazuo Ishikawa
  • Patent number: 7842140
    Abstract: The iron-based rare-earth nanocomposite magnet of the present invention has a composition T100?x?y?z?nQxRyTizMn, where T is Fe or a transition metal element in which Fe is partially replaced by Co and/or Ni; Q is B and/or C; R is at least one rare-earth element including substantially no La or Ce; and M is at least one metal element selected from Al, Si, V, Cr, Mn, Cu, Zn, Ga, Zr, Nb, Mo, Ag, Hf, Ta, W, Pt, Au and Pb. x, y, z and n satisfy 5?x?10 at %, 7?y?10 at %, 0.1?z?5 at % and 0?n?10 at %, respectively. The magnet includes R2Fe14B-type compound phases and ? —Fe phases forming a magnetically coupled nanocomposite magnet structure. The R2Fe14B-type compound phases have an average crystal grain size of 30 nm to 300 nm and the ? —Fe phases have an average crystal grain size of 1 nm to 20 nm. The magnet has magnetic properties including a coercivity of at least 400 kA/m and a remanence of at least 0.9 T.
    Type: Grant
    Filed: December 13, 2005
    Date of Patent: November 30, 2010
    Assignee: Hitachi Metals, Ltd.
    Inventors: Hirokazu Kanekiyo, Toshio Miyoshi
  • Publication number: 20100219922
    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: Application
    Filed: May 17, 2010
    Publication date: September 2, 2010
    Applicant: HITACHI METALS, LTD.
    Inventors: Yasutaka SHIGEMOTO, Satoshi HIROSAWA, Toshio MIYOSHI
  • Publication number: 20090223606
    Abstract: The iron-based rare-earth nanocomposite magnet of the present invention has a composition T100-x-y-z-nQxRyTizMn, where T is Fe or a transition metal element in which Fe is partially replaced by Co and/or Ni; Q is B and/or C; R is at least one rare-earth element including substantially no La or Ce; and M is at least one metal element selected from Al, Si, V, Cr, Mn, Cu, Zn, Ga, Zr, Nb, Mo, Ag, Hf, Ta, W, Pt, Au and Pb. x, y, z and n satisfy 5?x?10 at %, 7?y?10 at %, 0.1?z?5 at % and 0?n?10 at %, respectively. The magnet includes R2Fe14B-type compound phases and ? —Fe phases forming a magnetically coupled nanocomposite magnet structure. The R2Fe14B-type compound phases have an average crystal grain size of 30 nm to 300 nm and the ? —Fe phases have an average crystal grain size of 1 nm to 20 nm. The magnet has magnetic properties including a coercivity of at least 400 kA/m and a remanence of at least 0.9 T.
    Type: Application
    Filed: December 13, 2005
    Publication date: September 10, 2009
    Applicant: HITACHI METALS, LTD.
    Inventors: Hirokazu Kanekiyo, Toshio Miyoshi
  • Publication number: 20090127494
    Abstract: A method for producing a rare-earth alloy based binderless magnet according to the present invention includes the steps of: (A) providing a rapidly solidified rare-earth alloy magnetic powder; and (B) compressing and compacting the rapidly solidified rare-earth alloy magnetic powder by a cold process without using a resin binder, thereby obtaining a compressed compact, 70 vol % to 95 vol % of which is the rapidly solidified rare-earth alloy magnetic powder.
    Type: Application
    Filed: August 3, 2006
    Publication date: May 21, 2009
    Applicants: HITACHI METALS, LTD., NIPPON KAGAKU YAKIN CO., LTD.
    Inventors: Hirokazu Kanekiyo, Toshio Miyoshi, Katsunori Bekki, Ikuo Uemoto, Kazuo Ishikawa
  • Publication number: 20090129966
    Abstract: An iron-based rare-earth nanocomposite magnet according to the present invention includes an Nd2Fe14B phase and an ?-Fe phase and has a composition represented by the compositional formula: T100-x-y-z-n(B1-qCq)xRyTizMn, where T is at least one transition metal element selected from the group consisting of Fe, Co and Ni and always including Fe, R is at least one rare-earth element including substantially no La or Ce, and M is at least one metal element selected from the group consisting of Al, Si, V, Cr, Mn, Cu, Zn, Ga, Zr, Nb, Mo, Ag, Hf, Ta, W, Pt, Au and Pb, and the mole fractions x, y, z, n and q satisfy the inequalities of: 4 at %?x?10 at %, 6 at %?y?10 at %, 0.05 at %?z?5 at %, 0 at %?n?10 at %, and 0.05?q?0.5, respectively. The magnet includes 5 vol % to 60 vol % of ?-Fe phase with an average crystal grain size of 1 nm to 50 nm and 40 vol % to 90 vol % of Nd2Fe14B phase with an average crystal grain size of 5 nm to 100 nm.
    Type: Application
    Filed: March 22, 2006
    Publication date: May 21, 2009
    Applicant: Hitachi Metals, Ltd.
    Inventors: Hirokazu Kanekiyo, Toshio Miyoshi, Satoshi Hirosawa
  • Patent number: 7507302
    Abstract: A rare-earth alloy powder is obtained by rapidly cooling a melt of an alloy by an atomization process. The alloy has a composition represented by (Fe1-mTm)100-x-y-zQxRyTizMn, where T is at least one of Co and Ni, Q is at least one of B and C, R is at least one of the rare-earth metal elements and yttrium, and M is at least one of Nb, Zr, Mo, Ta and Hf. The mole fractions x, y, z, m and n satisfy 10 at %<x?25 at %, 6 at %?y<10 at %, 0.1 at %?z?12 at %, 0?m?0.5, and 0 at %?n?10 at %, respectively. By adding Ti to the alloy, the nucleation and growth of ?-Fe during the rapid quenching process can be minimized.
    Type: Grant
    Filed: July 19, 2002
    Date of Patent: March 24, 2009
    Assignee: Hitachi Metals, Ltd.
    Inventors: Toshio Miyoshi, Hirokazu Kanekiyo, Satoshi Hirosawa
  • Patent number: 7297213
    Abstract: An iron-based rare earth alloy magnet has a composition represented by the general formula: (Fe1-mTm)100-x-y-zQxRyMz, where T is at least one element selected from the group consisting of Co and Ni; Q is at least one element selected from the group consisting of B and C; R is at least one rare earth element substantially excluding La and Ce; and M is at least one metal element selected from the group consisting of Ti, Zr and Hf and always includes Ti. In this formula, the mole fractions x, y, z and m meet the inequalities of: 10 at %<x?20 at %; 6 at %?y<10 at %; 0.1 at %?z?12 at %; and 0?m?0.5, respectively.
    Type: Grant
    Filed: December 24, 2003
    Date of Patent: November 20, 2007
    Assignee: Neomax Co., Ltd.
    Inventors: Hirokazu Kanekiyo, Toshio Miyoshi, Satoshi Hirosawa, Yasutaka Shigemoto, Yusuke Shioya
  • Patent number: 7261781
    Abstract: A nanocomposite magnet has a composition represented by (Fe1-mTm)100-x-y-z-nQxRyTizMn, where T is at least one of Co and Ni, Q is at least one of B and C, R is at least one rare earth element that always includes at least one of Nd and Pr and optionally includes Dy and/or Tb, and M is at least one element selected from the group consisting of Al, Si, V, Cr, Mn, Cu, Zn, Ga, Zr, Nb, Mo, Ag, Hf, Ta, W, Pt, Au and Pb. The mole fractions x, y, z, m and n satisfy 10 at %<x?20 at %, 6 at %?y<10 at %, 0.5 at %?z?12 at %, 0?m?0.5 and 0 at %?n?10 at %, respectively. The nanocomposite magnet has an oxygen content of at most about 1,500 ppm by mass.
    Type: Grant
    Filed: November 19, 2002
    Date of Patent: August 28, 2007
    Assignee: Neomax Co., Ltd.
    Inventors: Hirokazu Kanekiyo, Toshio Miyoshi, Satoshi Hirosawa
  • Publication number: 20070131309
    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: Application
    Filed: December 6, 2004
    Publication date: June 14, 2007
    Applicant: NEOMAX CO., LTD.
    Inventors: Yasutaka Shigemoto, Satoshi Hirosawa, Toshio Miyoshi
  • Patent number: 7217328
    Abstract: A compound for a rare-earth bonded magnet includes a rare-earth alloy powder and a binder. The rare-earth alloy powder includes at least about 2 mass % of Ti-containing nanocomposite magnet powder particles with a composition represented by (Fe1-mTm)100-x-y-zQxRyMz, where T is Co and/or Ni; Q is B with or without C; R is at least one rare-earth element substantially excluding La and Ce; M is at least one metal element selected from Ti, Zr and Hf and always includes Ti; and 10<x?20 at %; 6?y<10 at %; 0.1?z?12 at %; and 0?m?0.5. The particles include at least two ferromagnetic crystalline phases, in which hard magnetic phases have an average crystal grain size of about 10 nm to about 200 nm, soft magnetic phases have an average crystal grain size of about 1 nm to about 100 nm; and the average crystal grain size of the soft magnetic phases is smaller than that of the hard magnetic phases.
    Type: Grant
    Filed: August 18, 2003
    Date of Patent: May 15, 2007
    Assignee: Neomax Co., Ltd.
    Inventors: Takeshi Nishiuchi, Hirokazu Kanekiyo, Satoshi Hirosawa, Toshio Miyoshi
  • Patent number: 7208097
    Abstract: An iron-based rare earth alloy nanocomposite magnet has a composition represented by (Fe1-mTm)100-x-y-zQxRyTiz, where T is Co and/or Ni, Q is B and/or C and R is rare earth element(s) including substantially no La or Ce. x, y, z and m satisfy 10 at %<x?17 at %, 7 at %?y<10 at %, 0.5 at %?z?6 at % and 0?m?0.5, respectively. The magnet includes crystal grains of an R2T14Q type compound having an average grain size of 20 nm to 200 nm and a ferromagnetic iron-based boride that exists in a grain boundary between the crystal grains of the R2T14Q type compound. The boride is dispersed in, or present in the form of a film over, the grain boundary to cover at least partially the surface of the crystal grains of the R2T14Q type compound.
    Type: Grant
    Filed: May 8, 2002
    Date of Patent: April 24, 2007
    Assignee: Neomax Co., Ltd.
    Inventors: Hirokazu Kanekiyo, Toshio Miyoshi, Satoshi Hirosawa
  • Patent number: 6890392
    Abstract: A method of making a material alloy for an iron-based rare earth magnet includes the step of forming a melt of an alloy with a composition of (Fe1-mTm)100-x-y-z-n(B1-pCp)xRyTi2Mn. T is Co and/or Ni; R is at least one element selected from Y (yttrium) and the rare earth elements; and M is at least one element selected from Al, Si, V, Cr, Mn, Ni, Cu, Zn, Ga, Zr, Nb, Mo, Ag, Hf, Ta, W, Pt, Au and Pb, wherein the following inequalities are satisfied: 10<x?25 at %, *6?y<10 at %, 0.5?z?12 at %, 0?m?0.5, 0?n?10 at % and 0?p?0.25. Next, the melt is fed onto a shoot with a guide surface tilted at about 1 degree to about 80 degrees with respect to a horizontal plane, thereby moving the melt onto a melt/roller contact region. The melt is then rapidly cooled using a chill roller to make a rapidly solidified alloy including an R2Fe14B phase.
    Type: Grant
    Filed: August 19, 2002
    Date of Patent: May 10, 2005
    Assignee: Neomax Co., Ltd.
    Inventors: Hirokazu Kanekiyo, Toshio Miyoshi, Satoshi Hirosawa
  • Publication number: 20050040923
    Abstract: A nanocomposite magnet represented by the general formula: (Fe1-mTm)100-x-y-z-w-n(B1-pCp)xRyTizVwMn, where T is Co and/or Ni; R is a rare-earth element; M is at least one element selected from Al, Si, Cr, Mn, Cu, Zn, Ga, Nb, Zr, Mo, Ag, Ta and W; and x, y, z, w, n, m and p satisfy: 10 at %<x?15 at %; 4 at %?y<7 at %; 0.5 at %?z?8 at %; 0.01 at %?w?6 at %; 0 at %?n?10 at %; 0?m?0.5; and 0.01?p?0.5, respectively. The magnet includes a hard magnetic phase with an R2Fe14B type crystal structure and a soft magnetic phase. At least one of the coercivity and the maximum energy product of the nanocomposite magnet is at least 1% higher than that of a magnet including no V.
    Type: Application
    Filed: October 8, 2003
    Publication date: February 24, 2005
    Inventors: Toshio Miyoshi, Hirokazu Kanekiyo
  • Patent number: 6814776
    Abstract: An iron-based rare-earth alloy powder includes: a first iron-based rare-earth alloy powder, which has a mean particle size of 10 &mgr;m to 70 &mgr;m and of which the powder particles have aspect ratios of 0.4 to 1.0; and a second iron-based rare-earth alloy powder, which has a mean particle size of 70 &mgr;m to 300 &mgr;m and of which the powder particles have aspect ratios of less than 0.3. The first and second iron-based rare-earth alloy powders are mixed at a volume ratio of 1:49 to 4:1. In this manner, an iron-based rare-earth alloy powder with increased flowability and a compound to make a magnet are provided.
    Type: Grant
    Filed: July 30, 2003
    Date of Patent: November 9, 2004
    Assignee: Neomax Co., Ltd.
    Inventors: Hirokazu Kanekiyo, Hirokazu Kitayama, Satoshi Hirosawa, Toshio Miyoshi