Patents by Inventor Noboru Menjo

Noboru Menjo 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: 9266311
    Abstract: There is provided the manufacturing method of a laminated magnet film end product, including the steps of: a first step of preparing magnet films, each of the magnet films having a thickness of 40 ?m to 300 ?m, and having a nanocrystalline structure which is magnetically isotropic; a second step of applying a self-bonding resin composition with film formability on each of the magnet films so as to prepare a plurality of self-bonding magnet films, each being composed of a magnet film and a self-bonding layer; a third step of mechanically processing each of the plurality of the self-bonding magnet films so as to be solid or hollow disc; a fourth step of preparing a laminated magnet film by laminating the plurality of self-bonding magnetic films; a fifth step of melting each self-bonding layer of the laminated magnet film and then cooling and solidifying each self-bonding layer so as to integrally rigidify the laminated magnet film; and a sixth step of magnetizing the rigidified laminated magnet film.
    Type: Grant
    Filed: April 21, 2011
    Date of Patent: February 23, 2016
    Assignee: MINEBEA CO., LTD.
    Inventors: Fumitoshi Yamashita, Shinsaku Nishimura, Noboru Menjo
  • Patent number: 8404141
    Abstract: A rare earth bonded magnet is provided which is produced such that a mixture which comprises: a rare earth magnet powder; a resin binder comprising a thermosetting resin; an organic phosphorus compound; and a coupling agent is compress-molded, heated and cured, wherein the organic phosphorus compound and the coupling agent are represented by the following respective chemical formulas (structural formulas):
    Type: Grant
    Filed: March 18, 2010
    Date of Patent: March 26, 2013
    Assignee: Minebea Co., Ltd.
    Inventors: Noboru Menjo, Kinji Uchiyama, Yuki Takeda
  • Patent number: 8269391
    Abstract: A micro rotor is disclosed and includes a plurality of circular or annular plate-shaped thick film magnets which each include an isotropic magnet with a thickness t1 having an in-plane remanence Mr of 0.95 T or more and a coercivity HcJ of 400 kA/m or more and a non-magnetic material with a thickness t2 adapted to isolate two adjacent isotropic magnets where the ratio of t1/t2 is eight or more and which are stacked on one another in multiple layers in the rotation axis direction, wherein at least two pole pairs are provided and a mean magnetic path of in-plane direction having a permeance (B/?oH) of five or more achieved by the magnet alone is provided, whereby eddy current is reduced. Also disclosed are a radial gap type brushless DC motor, a PM stepping motor and an electric generator which incorporate the above described micro rotor.
    Type: Grant
    Filed: June 1, 2010
    Date of Patent: September 18, 2012
    Assignee: Minebea Co., Ltd.
    Inventors: Fumitoshi Yamashita, Shinsaku Nishimura, Noboru Menjo
  • Publication number: 20110266894
    Abstract: There is provided the manufacturing method of a laminated magnet film, including the steps of: a first step of preparing a magnet film, 40 ?m to 300 ?m in thickness, provided with a nanocrystalline structure magnetically isotropic; a second step of applying a self-bonding resin composition with film formability on the magnet film preparing a self-bonding magnet film composed of the magnet film and a self-bonding layer; a third step of mechanically processing the self-bonding magnet film being solid or hollow; a fourth step of preparing the laminated magnet film by laminating the self-bonding magnet films; a fifth step of melting the self-bonding layer of the laminated magnet film and then cooling and solidifying the self-bonding layer to integrally rigidify the laminated magnet film; and a sixth step of magnetizing the rigidified laminated magnet film.
    Type: Application
    Filed: April 21, 2011
    Publication date: November 3, 2011
    Applicant: MINEBEA CO., LTD.
    Inventors: Fumitoshi YAMASHITA, Shinsaku NISHIMURA, Noboru MENJO
  • Publication number: 20100308679
    Abstract: A micro rotor is disclosed and includes a plurality of circular or annular plate-shaped thick film magnets which each include an isotropic magnet with a thickness t1 having an in-plane remanence Mr of 0.95 T or more and a coercivity HcJ of 400 kA/m and a non-magnetic material with a thickness t2 adapted to isolate two adjacent isotropic magnets where the ratio of t1/t2 is eight or more and which are stacked on one another in multiple layers in the rotation axis direction, wherein at least two pole pairs are provided and a mean magnetic path of in-plane direction having a permeance (B/?oH) of five or more achieved by the magnet alone is provided, whereby eddy current is reduced. Also disclosed are a radial gap type brushless DC motor, a PM stepping motor and an electric generator which incorporate the above described micro rotor.
    Type: Application
    Filed: June 1, 2010
    Publication date: December 9, 2010
    Applicant: MINEBEA CO., LTD.
    Inventors: Fumitoshi YAMASHITA, Shinsaku NISHIMURA, Noboru MENJO
  • Publication number: 20100245006
    Abstract: A rare earth bonded magnet is provided which is produced such that a mixture which comprises: a rare earth magnet powder; a resin binder comprising a thermosetting resin; an organic phosphorus compound; and a coupling agent is compress-molded, heated and cured, wherein the organic phosphorus compound and the coupling agent are represented by the following respective chemical formulas (structural formulas):
    Type: Application
    Filed: March 18, 2010
    Publication date: September 30, 2010
    Applicant: MINEBEA CO., LTD.
    Inventors: Noboru Menjo, Kinji Uchiyama, Yuki Takeda
  • Publication number: 20090096561
    Abstract: In order to achieve excellent heat resistance, durability and weatherability for use in an extended range of temperature environments, a rare earth bonded magnet is formed such that a material mixture comprising: a rare earth magnetic powder having a particle diameter ranging from 30 ?m to 500 ?m; a resin binder constituted by a thermosetting resin; and an organic phosphorous compound, is compression-molded and hardened, wherein the organic phosphorous compound is uniformly dispersed in the resin binder.
    Type: Application
    Filed: March 26, 2008
    Publication date: April 16, 2009
    Applicant: MINEBEA CO., LTD.
    Inventors: Noboru Menjo, Kinji Uchiyama, Yuki Takeda, Osamu Kobayashi
  • Patent number: 7300600
    Abstract: In a rare earth bonded magnet comprising a mixture of rare earth magnetic powder, thermosetting resin, and lubricant, the lubricant is constituted by amino-acid compound, specifically either N-lauroyl-L-lysine or N-lauroyl-asparaginic acid. The content of the amino-acid compound as lubricant in the mixture is set to range between 0.01 wt % and 1.0 wt % of the magnetic powder. Since the amino-acid compound has a high decomposition point, the resultant magnet after heat-curing treatment has a sufficient mechanical strength. Also, the amino-acid compound is nonhygroscopic, and therefore oxidation resistance and humidity resistance are good enough. Further, since the amino-acid compound produces a small amount of outgas, the resultant magnet can be suitably and reliably used in a hard disk drive which has stringent requirements, especially on outgas.
    Type: Grant
    Filed: February 25, 2005
    Date of Patent: November 27, 2007
    Assignee: Minebea Co., Ltd
    Inventors: Shinsaku Nishimura, Noboru Menjo, Toshihiko Miura
  • Publication number: 20050211947
    Abstract: In a rare earth bonded magnet comprising a mixture of rare earth magnetic powder, thermosetting resin, and lubricant, the lubricant is constituted by amino-acid compound, specifically either N-lauroyl-L-lysine or N-lauroyl-asparaginic acid. The content of the amino-acid compound as lubricant in the mixture is set to range between 0.01 wt % and 1.0 wt % of the magnetic powder. Since the amino-acid compound has a high decomposition point, the resultant magnet after heat-curing treatment has a sufficient mechanical strength. Also, the amino-acid compound is nonhygroscopic, and therefore oxidation resistance and humidity resistance are good enough. Further, since the amino-acid compound produces a small amount of outgas, the resultant magnet can be suitably and reliably used in a hard disk drive which has stringent requirements, especially on outgas.
    Type: Application
    Filed: February 25, 2005
    Publication date: September 29, 2005
    Applicant: MINEBEA CO., LTD.
    Inventors: Shinsaku Nishimura, Noboru Menjo, Toshihiko Miura