Patents by Inventor Keiichiro Oka

Keiichiro Oka 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: 8981614
    Abstract: Included are a pair of insulators arranged on axial end surfaces of a split core, and an insulating film attached to lateral side surfaces of the tooth part, for insulating the split core from a coil wound around the tooth part. Each insulator includes projections projecting further than a tooth front end part in the circumferential direction, slits which are formed in the respective projections to a corresponding axial end surface side of the tooth front end part and into which the insulating film is inserted, and ribs formed, on an end surface side in the circumferential direction, in the respective projections. The insulating film inserted into the slits is folded back to a back yoke part side with the ribs interposed therein, and fixed by being interposed between the ribs at tip portions of projections of adjacent insulators. Accordingly, the insulating film can be assuredly fixed and prevented from escaping from a slot.
    Type: Grant
    Filed: April 5, 2010
    Date of Patent: March 17, 2015
    Assignee: Mitsubishi Electric Corporation
    Inventors: Keiichiro Oka, Hiroyuki Akita, Toshio Arai
  • Publication number: 20150028710
    Abstract: Provided is a rotor for a rotating electric machine which includes: an N pole integrally-stacked core in which a plurality of stacked tooth portions that contact with N pole side portions of adjacent ones of first permanent magnets are integrated with each other; and an S pole integrally-stacked core in which a plurality of stacked tooth portions that contact with S pole side portions of adjacent ones of the first permanent magnets are integrated with each other, and in which the N pole integrally-stacked core and the S pole integrally-stacked core are disposed around a rotation shaft having a non-magnetic outer circumferential surface so as to dispose the first permanent magnets and a gap therebetween.
    Type: Application
    Filed: March 13, 2013
    Publication date: January 29, 2015
    Applicant: Mitsubishi Electric Corporation
    Inventors: Keiichiro Oka, Hiroyuki Akita
  • Publication number: 20150022048
    Abstract: Provided are an armature for rotary electric machine, an insulator therefor, and a coil winding device for winding a conductive wire on a tooth to which the insulator has been attached, wherein in each of all forward-wound coils and reversely-wound coils, a part wound on a first side surface of two side surfaces of each tooth that are opposed to the respective adjacent teeth forms a straight portion in which conductive wires in respective layers of the coil are parallel, a part wound on a second side surface forms a cross portion in which the conductive wire in an upper layer is wound in a crossed manner on the conductive wire in an adjacent lower layer, and an insulator has a guide for guiding the conductive wire along a base of an inner flange of the insulator at a first turn of each coil.
    Type: Application
    Filed: February 15, 2013
    Publication date: January 22, 2015
    Applicant: Mitsubishi Electric Corporation
    Inventors: Keiichiro Oka, Hiroyuki Akita, Kunihiro Yamaoka
  • Patent number: 8487501
    Abstract: An object of the invention is to provide an armature of an electric motor that provides a maximum of space for winding without causing an increase of the magnetic resistance and reduction of the coil space factor. The armature of the electric motor includes a stator yoke 5 of a stator core 1 wherein a plurality of the stator cores 1 forms a substantially annular shape; and a film insulator 4 formed corresponding to a tooth 6 and a stator yoke 5 of the tooth 6, shoes 2b and 3b being provided at locations corresponding to both side ends of a front portion of a protrusion 6a of the tooth 6, the film insulator 4 being fittingly fixed to grooves 2c and 3c by its being sandwiched between a connection-side insulator 2 and an opposite-side-of-connection insulator 3, the insulators 2 and 3 having grooves 2c and 3c at roots of the shoes 2b and 3b, respectively, along both side ends 6b of the front portion of the tooth 6.
    Type: Grant
    Filed: March 2, 2010
    Date of Patent: July 16, 2013
    Assignee: Mitsubishi Electric Corporation
    Inventors: Keiichiro Oka, Hiroyuki Akita, Toshio Arai
  • Publication number: 20120080976
    Abstract: Included are a pair of insulators arranged on axial end surfaces of a split core, and an insulating film attached to lateral side surfaces of the tooth part, for insulating the split core from a coil wound around the tooth part. Each insulator includes projections projecting further than a tooth front end part in the circumferential direction, slits which are formed in the respective projections to a corresponding axial end surface side of the tooth front end part and into which the insulating film is inserted, and ribs formed, on an end surface side in the circumferential direction, in the respective projections. The insulating film inserted into the slits is folded back to a back yoke part side with the ribs interposed therein, and fixed by being interposed between the ribs at tip portions of projections of adjacent insulators. Accordingly, the insulating film can be assuredly fixed and prevented from escaping from a slot.
    Type: Application
    Filed: April 5, 2010
    Publication date: April 5, 2012
    Applicant: Mitsubishi Electric Corporation
    Inventors: Keiichiro Oka, Hiroyuki Akita, Toshio Arai
  • Publication number: 20110273053
    Abstract: An object of the invention is to provide an armature of an electric motor that provides a maximum of space for winding without causing an increase of the magnetic resistance and reduction of the coil space factor. The armature of the electric motor includes a stator yoke 5 of a stator core 1 wherein a plurality of the stator cores 1 forms a substantially annular shape; and a film insulator 4 formed corresponding to a tooth 6 and a stator yoke 5 of the tooth 6, shoes 2b and 3b being provided at locations corresponding to both side ends of a front portion of a protrusion 6a of the tooth 6, the film insulator 4 being fittingly fixed to grooves 2c and 3c by its being sandwiched between a connection-side insulator 2 and an opposite-side-of-connection insulator 3, the insulators 2 and 3 having grooves 2c and 3c at roots of the shoes 2b and 3b, respectively, along both side ends 6b of the front portion of the tooth 6.
    Type: Application
    Filed: March 2, 2010
    Publication date: November 10, 2011
    Applicant: Mitsubishi Electric Corporation
    Inventors: Keiichiro Oka, Hiroyuki Akita, Toshio Arai
  • Patent number: 7345387
    Abstract: An automotive alternator in which a fan rotating together with a rotor to direct air from a suction aperture into a case, blow the air centrifugally, and discharge the air externally through a discharge aperture has a blade including an interposed portion extending axially from an end surface of a pole core between an adjacent pair of claw-shaped magnetic poles. For this reason, cooling of a rotor coil and a stator coil is improved by improving capacity of the fan in a limited space, thereby enabling output to be improved.
    Type: Grant
    Filed: August 9, 2004
    Date of Patent: March 18, 2008
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Hiroyuki Akita, Keiichiro Oka, Wakaki Miyaji, Toshiaki Kashihara
  • Publication number: 20060261688
    Abstract: An automotive alternator in which a fan rotating together with a rotor to direct air from a suction aperture into a case, blow the air centrifugally, and discharge the air externally through a discharge aperture has a blade including an interposed portion extending axially from an end surface of a pole core between an adjacent pair of claw-shaped magnetic poles. For this reason, cooling of a rotor coil and a stator coil is improved by improving capacity of the fan in a limited space, thereby enabling output to be improved.
    Type: Application
    Filed: August 9, 2004
    Publication date: November 23, 2006
    Inventors: Hiroyuki Akita, Keiichiro Oka, Wakaki Miyaji, Toshiaki Kashihara