Patents by Inventor Hirooki Tokoi

Hirooki Tokoi 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: 8659199
    Abstract: A stator and a rotor are oppositely arranged having a gap between the stator and the rotor in a direction parallel to a rotary shaft. The rotor has permanent magnets forming field magnetic poles and soft magnetic material segments to cover at least stator-facing surfaces of the respective permanent magnets. Each of the soft magnetic materials forms a composite part together with the permanent magnet. The rotor further has a disc-shaped nonmagnetic molded frame molded so as to cover the periphery of the composite part including the permanent magnet and the soft magnetic material segment while leaving a stator-facing surface of the soft magnetic material segment as an exposed surface. The composite part (including the permanent magnet and the soft magnetic material) and the nonmagnetic molded frame are integrated by molding of the molded material.
    Type: Grant
    Filed: December 17, 2010
    Date of Patent: February 25, 2014
    Assignee: Hitachi, Ltd.
    Inventors: Hirooki Tokoi, Yuji Enomoto
  • Publication number: 20140042842
    Abstract: A channel connecting a first opening formed on one side surface of a rotor and a second opening formed on the other side surface of the rotor is provided, and a first distance from a rotating shaft to the center of the first opening and a second distance from the rotating shaft to the center of the second opening are differentiated. A differential pressure is generated between the first opening and the second opening provided in the rotor by the differentiating the distances from the center of the rotating shaft to the first opening and the second opening, a flow of air is generated by the differential pressure from one surface or the other surface of the rotor to the other surface or the one surface, whereby the stator in proximity to the rotor may be cooled.
    Type: Application
    Filed: July 25, 2013
    Publication date: February 13, 2014
    Applicant: Hitachi, Ltd.
    Inventors: Hirooki TOKOI, Yuji ENOMOTO, Shigeki TOUNOSU
  • Publication number: 20140009009
    Abstract: An axial gap rotating-electric machine includes a stator, a rotor arranged via an air gap in the direction of an axis of rotation of a rotating-electric machine with respect to the stator, and a housing configured to accommodate the stator and the rotor, and the stator includes a plurality of stator cores arranged in the circumferential direction, coils configured to wind the peripheries of the respective stator cores, and a resin for molding the plurality of stator cores wound with the coils, and the stator cores each include a protruding portion protruding partly from the coil in the direction of axis of rotation, and a conductive member is provided so as to come into contact with peripheral surfaces of the protruding portions of the stator cores, and grounding is achieved by the conductive member.
    Type: Application
    Filed: July 3, 2013
    Publication date: January 9, 2014
    Inventors: Kenta DEGUCHI, Hirooki TOKOI, Zhuonan WANG, Norihisa IWASAKI, Yuji ENOMOTO
  • Patent number: 8575804
    Abstract: A magnetic gear comprises a first permanent magnet field having a plurality of permanent magnet magnetic poles, a second permanent magnet field having a plurality of permanent magnet magnetic poles, number of poles of which magnet is different from that of the first permanent magnet field, and a modulating magnetic pole arranged between the first permanent magnet field and the second permanent magnet field and having a plurality of pole pieces to modulate the number of poles of the first and second permanent magnet fields. Non-magnetic bars are provided between the plurality of pole pieces. One ends of the non-magnetic bars are fixed to a first non-magnetic end holding member and the other ends of the non-magnetic bars are electrically insulated from and fixed to a second non-magnetic end holding member.
    Type: Grant
    Filed: January 19, 2012
    Date of Patent: November 5, 2013
    Assignee: Hitachi, Ltd.
    Inventors: Junnosuke Nakatsugawa, Yuji Enomoto, Hirooki Tokoi, Hiroshi Morita, Norihisa Iwasaki
  • Publication number: 20120194021
    Abstract: A magnetic gear comprises a first permanent magnet field having a plurality of permanent magnet magnetic poles, a second permanent magnet field having a plurality of permanent magnet magnetic poles, number of poles of which magnet is different from that of the first permanent magnet field, and a modulating magnetic pole arranged between the first permanent magnet field and the second permanent magnet field and having a plurality of pole pieces to modulate the number of poles of the first and second permanent magnet fields. Non-magnetic bars are provided between the plurality of pole pieces. One ends of the non-magnetic bars are fixed to a first non-magnetic end holding member and the other ends of the non-magnetic bars are electrically insulated from and fixed to a second non-magnetic end holding member.
    Type: Application
    Filed: January 19, 2012
    Publication date: August 2, 2012
    Inventors: Junnosuke Nakatsugawa, Yuji Enomoto, Hirooki Tokoi, Hiroshi Morita, Norihisa Iwasaki
  • Publication number: 20120146445
    Abstract: An axial flux permanent magnet brushless machine according to the present invention includes: a housing; a stator comprising a stator core and a coil; two rotors each including a permanent magnet, and positioned so as to sandwich the stator in the axial direction with air gaps being left between the rotors and the stator; and a variable gap mechanism for changing distances of the air gaps; wherein the variable gap mechanism operates from a power source that supplies other rotational power than a rotational power of the axial flux permanent magnet brushless machine, and changes the distances of the air gaps by shifting the rotors in the axial direction.
    Type: Application
    Filed: December 12, 2011
    Publication date: June 14, 2012
    Applicant: Hitachi, Ltd.
    Inventors: Hirooki TOKOI, Yuji ENOMOTO
  • Publication number: 20110148224
    Abstract: A stator and a rotor are oppositely arranged having a gap between the stator and the rotor in a direction parallel to a rotary shaft. The rotor has permanent magnets forming field magnetic poles and soft magnetic material segments to cover at least stator-facing surfaces of the respective permanent magnets. Each of the soft magnetic materials forms a composite part together with the permanent magnet. The rotor further has a disc-shaped nonmagnetic molded frame molded so as to cover the periphery of the composite part including the permanent magnet and the soft magnetic material segment while leaving a stator-facing surface of the soft magnetic material segment as an exposed surface. The composite part (including the permanent magnet and the soft magnetic material) and the nonmagnetic molded frame are integrated by molding of the molded material.
    Type: Application
    Filed: December 17, 2010
    Publication date: June 23, 2011
    Inventors: Hirooki TOKOI, Yuji Enomoto
  • Publication number: 20110076175
    Abstract: In a punch die for powder compacting, a powder compacting equipment equipped with the punch die, and a forming method with the equipment, for suppressing the occurrence of stress concentration in the die without changing a shape of a powder compacting body, the punch die is used to form a cylindrical member by powder compacting, which has a substantially cylindrical shape and has a protrusion portion formed on the inner peripheral side thereof to protrude in the axial direction or a stepped portion or a concave portion formed on the inner peripheral side thereof in the radial direction. The punch die has a substantially cylindrical shape, and has a protrusion portion formed on at least a part of the inner peripheral surface or the outer peripheral surface thereof to protrude toward the center axis.
    Type: Application
    Filed: August 20, 2010
    Publication date: March 31, 2011
    Inventors: Hirooki Tokoi, Kinya Kobayashi