Patents by Inventor Shogo MUROYA

Shogo MUROYA 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: 20210304935
    Abstract: To provide a ferrite sintered magnet having a high residual magnetic flux density (Br), a high coercive force (HcJ), a good production stability, and also able to produce at a low cost. The ferrite sintered magnet includes a hexagonal M-type ferrite including A, R, Fe, and Co in an atomic ratio of A1-xRx(Fe12-yCoy)zO19. A is at least one selected from Sr, Ba, and Pb. R is La only or La and at least one selected from rare earth elements. 0.14?x?0.22, 11.60?(12-y)z?11.99, and 0.13?yz?0.17 are satisfied. 0.30?Mc?0.63 is satisfied in which Mc is CaO content (mass %) converted from a content of Ca included in the ferrite sintered magnet.
    Type: Application
    Filed: March 15, 2021
    Publication date: September 30, 2021
    Applicant: TDK CORPORATION
    Inventors: Shogo MUROYA, Yoshitaka MURAKAWA, Hiroyuki MORITA, Masanori IKEDA
  • Publication number: 20210304934
    Abstract: To provide a ferrite sintered magnet having a high residual magnetic flux density (Br) and a high coercive force (HcJ), and also able to produce at a low cost. The ferrite sintered magnet includes a hexagonal M-type ferrite including A, R, Fe, and Co in an atomic ratio of A1-xRx(Fe12-yCoy)zO19. A is at least one selected from Sr, Ba, and Pb. R is La only or La and at least one selected from rare earth elements. 0.13?x?0.23, 10.80?(12?y)z?12.10, and 0.13?yz?0.20 are satisfied.
    Type: Application
    Filed: March 11, 2021
    Publication date: September 30, 2021
    Applicant: TDK CORPORATION
    Inventors: Shogo MUROYA, Yoshitaka MURAKAWA, Hiroyuki MORITA, Masanori IKEDA
  • Publication number: 20210296032
    Abstract: A ferrite sintered magnet including ferrite grains having a hexagonal crystal structure. The ferrite grains satisfy 0.56?W?0.68 where W is an average value of circularities of the ferrite grains in a cross section parallel to an axis of easy magnetization.
    Type: Application
    Filed: March 19, 2021
    Publication date: September 23, 2021
    Applicant: TDK CORPORATION
    Inventors: Masanori IKEDA, Hiroyuki MORITA, Yoshitaka MURAKAWA, Shogo MUROYA
  • Publication number: 20210296030
    Abstract: A ferrite sintered magnet including 0.010 mass % or more and 0.090 mass % or less of Mg in terms of MgO.
    Type: Application
    Filed: March 11, 2021
    Publication date: September 23, 2021
    Applicant: TDK CORPORATION
    Inventors: Hiroyuki MORITA, Masanori IKEDA, Yoshitaka MURAKAWA, Shogo MUROYA
  • Publication number: 20210118598
    Abstract: A ferrite sintered magnet 100 comprises M-type ferrite crystal grains 4 and multiple-crystal grain boundaries 6b surrounded by three or more of the M-type ferrite crystal grains 4. The ferrite sintered magnet 100 contains at least Fe, Ca, B, and Si, and contains 0.005 to 0.9 mass % of B in terms of B2O3. The multiple-crystal grain boundaries 6b contain Si and Ca, and in a case where the molar ratio of Ca to Si in the multiple-crystal grain boundaries 6b is represented by (Ca/Si)G, the following formula is satisfied. 0.1<(Ca/Si)G<0.
    Type: Application
    Filed: October 14, 2020
    Publication date: April 22, 2021
    Applicant: TDK Corporation
    Inventors: Yoshitaka MURAKAWA, Hiroyuki MORITA, Masanori IKEDA, Shogo MUROYA, Tomokazu ISHIKURA
  • Publication number: 20210090768
    Abstract: The present invention provides a ferrite sintered magnet comprising ferrite crystal grains having a hexagonal structure, wherein the ferrite sintered magnet comprises metallic elements at an atomic ratio represented by formula (1). In formula (1), R is at least one element selected from the group consisting of Bi and rare-earth elements, and R comprises at least La. In formula (1), w, x, z and m satisfy formulae (2) to (5). The above-mentioned ferrite sintered magnet further has a coefficient of variation of a size of the crystal grains in a section parallel to a c axis of less than 45%. Ca1-w-xRwSrxFezCom??(1) 0.360?w=0.420??(2) 0.110?x?0.173??(3) 8.51?z?9.71??(4) 0.208?m?0.
    Type: Application
    Filed: September 21, 2020
    Publication date: March 25, 2021
    Applicant: TDK Corporation
    Inventors: Tomokazu ISHIKURA, Masanori IKEDA, Yoshitaka MURAKAWA, Hiroyuki MORITA, Shogo MUROYA
  • Publication number: 20200312493
    Abstract: A ferrite sintered magnet comprising an M type Sr ferrite having a hexagonal structure as a main phase, wherein the ferrite sintered magnet does not substantially comprise a rare earth element and Co, a content of B is 0.005 to 0.9% by mass in terms of B2O3, and a content of Zn is 0.01 to 1.2% by mass in terms of ZnO.
    Type: Application
    Filed: March 19, 2020
    Publication date: October 1, 2020
    Applicant: TDK Corporation
    Inventors: Yoshitaka MURAKAWA, Shogo MUROYA, Hiroyuki MORITA, Masanori IKEDA
  • Publication number: 20200312496
    Abstract: A ferrite sintered magnet 100 comprises M-type ferrite crystal grains 4 having a hexagonal structure, two-crystal grain boundaries 6a formed between two of the M-type ferrite crystal grains 4, and multiple-crystal grain boundaries 6b surrounded by three or more of the M-type ferrite crystal grains 4. This ferrite sintered magnet 100 contains at least Fe, Ca, B, and Si, and contains B in an amount of 0.005 to 0.9 mass % in terms of B2O3, the two-crystal grain boundaries 6a and the multiple-crystal grain boundaries 6b contain Si and Ca, and in a cross-section parallel to a c-axis of the ferrite sintered magnet, when the number of multiple-crystal grain boundaries 6b having a maximum length of 0.49 to 5 ?m per cross-sectional area of 76 ?m2 is N, N is 7 or less.
    Type: Application
    Filed: March 23, 2020
    Publication date: October 1, 2020
    Applicant: TDK Corporation
    Inventors: Yoshitaka MURAKAWA, Shogo MUROYA, Hiroyuki MORITA, Masanori IKEDA
  • Publication number: 20200312495
    Abstract: A ferrite sintered magnet comprising an M type Sr ferrite having a hexagonal structure as a main phase, wherein the ferrite sintered magnet comprises La and Co, a content of B is 0.005 to 0.9% by mass in terms of B2O3, a content of Zn is 0.01 to 1.2% by mass in terms of ZnO, and the ferrite sintered magnet satisfies [La]/[Zn]?0.79 and [Co]/[Zn]?0.67 when an atomic concentration of La is represented by [La], an atomic concentration of Co is represented by [Co], and an atomic concentration of Zn is represented by [Zn].
    Type: Application
    Filed: March 20, 2020
    Publication date: October 1, 2020
    Applicant: TDK Corporation
    Inventors: Yoshitaka MURAKAWA, Shogo MUROYA, Hiroyuki MORITA, Masanori IKEDA
  • Publication number: 20200312497
    Abstract: This ferrite sintered magnet comprises ferrite phases having a magnetoplumbite type crystal structure. This magnet comprises an element R, an element M, Fe, Co, B, Mn and Cr, the element R is at least one element selected from rare earth elements including Y, the element M is at least one element selected from the group consisting of Ca, Sr and Ba, with Ca being an essential element, and when an atomic composition of metallic elements is represented by R1-xMxFem-yCoy, x, y and m satisfy formulae: 0.2?x?0.8??(1) 0.1?y?0.65??(2) 3?m<14??(3). Additionally, a content of B is 0.1 to 0.4% by mass in terms of B2O3, a content of Mn is 0.15 to 1.02% by mass in terms of MnO, and a content of Cr is 0.02 to 2.01% by mass in terms of Cr2O3.
    Type: Application
    Filed: March 20, 2020
    Publication date: October 1, 2020
    Applicant: TDK Corporation
    Inventors: Shogo MUROYA, Yoshitaka MURAKAWA, Hiroyuki MORITA, Masanori IKEDA
  • Publication number: 20200312494
    Abstract: A ferrite sintered magnet 100 comprises M-type ferrite crystal grains 4 having a hexagonal crystal structure, two-crystal grain boundaries 6a formed between two of the M-type ferrite crystal grains 4, and multiple-crystal grain boundaries 6b surrounded by three or more of the M-type ferrite crystal grains 4. This ferrite sintered magnet 100 contains at least Fe, Ca, B, and Si, and contains B in an amount of 0.005 to 0.9 mass % in terms of B2O3, the two-crystal grain boundaries 6a and the multiple-crystal grain boundaries 6b contain Si and Ca, and in a cross-section parallel to a c-axis of the ferrite sintered magnet, when the number of multiple-crystal grain boundaries having a maximum length of 0.088 or more and less than 0.49 ?m per cross-sectional area of 76 ?m2 is P, P is 8 or more.
    Type: Application
    Filed: March 20, 2020
    Publication date: October 1, 2020
    Applicant: TDK Corporation
    Inventors: Yoshitaka MURAKAWA, Shogo MUROYA, Hiroyuki MORITA, Masanori IKEDA
  • Publication number: 20200255339
    Abstract: This ferrite sintered magnet comprises metallic elements at an atomic ratio represented by formula (1): Ca1-w-xRwSrxFezCom ??(1) in formula (1), R is at least one element selected from the group consisting of rare-earth elements and Bi, and R comprises at least La, in formula (1), w, x, z and m satisfy formulae (2) to (5): 0.360?w?0.420 ??(2) 0.110?x?0.173 ??(3) 8.51?z?9.71 ??(4) 0.208?m?0.269 ??(5), and in a section parallel to an axis of easy magnetization, when the number of total ferrite grains is N and the number of ferrite grains having a stacking fault is n, 0?n/N?0.20 is satisfied.
    Type: Application
    Filed: February 5, 2020
    Publication date: August 13, 2020
    Applicant: TDK Corporation
    Inventors: Masanori IKEDA, Hiroyuki MORITA, Yoshitaka MURAKAWA, Shogo MUROYA
  • Publication number: 20200251262
    Abstract: A ferrite sintered magnet comprises a plurality of main phase grains containing a ferrite having a hexagonal structure, wherein at least some of the main phase grains are core-shell structure grains each having a core and a shell covering the core; and wherein the minimum value of the content of La in the core is [La]c atom %; the minimum value of the content of Co in the core is [Co]c atom %; the maximum value of the content of La in the shell is [La]s atom %; the maximum value of the content of Co in the shell is [Co]s atom %; [La]c+[Co]c is 3.08 atom % or more and 4.44 atom % or less; and [La]s+[Co]s is 7.60 atom % or more and 9.89 atom % or less.
    Type: Application
    Filed: January 31, 2020
    Publication date: August 6, 2020
    Applicant: TDK Corporation
    Inventors: Hiroyuki MORITA, Masanori IKEDA, Yoshitaka MURAKAWA, Shogo MUROYA