Patents by Inventor Koji Yabe

Koji Yabe 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: 20150364959
    Abstract: An interior permanent magnet motor includes: a rotor; a stator; and a plurality of permanent magnets respectively inserted into a plurality of magnet insertion holes formed in a rotor core, the rotor core being formed by laminating a plurality of magnetic steel sheets, the magnetic steel sheets including first magnetic steel sheets each not having a magnet stopper in the magnet insertion hole, and second magnetic steel sheets each having magnet stoppers at both end portions of the magnet insertion hole, the rotor core including a laminate of the magnetic steel sheets in a lamination mode in which, when Hn represents a distance between an upper end surface of the second magnetic steel sheet and an upper end surface of the n-th second magnetic steel sheet, a progression of differences of Hn is a geometric progression.
    Type: Application
    Filed: February 20, 2013
    Publication date: December 17, 2015
    Applicant: MITSUBISHI ELECTRIC CORPORATION
    Inventors: Naohiro OKETANI, Masahiro NIGO, Kazuhiko BABA, Koji YABE
  • Patent number: 9178392
    Abstract: A rotor of a permanent magnet embedded motor according to this invention includes: a rotor iron core formed by stacking a predetermined number of electromagnetic steel plates perforated in a predetermined shape; a plurality of permanent magnet insertion holes formed along an outer circumferential section of the rotor iron core; permanent magnet end gaps provided at both ends of the permanent magnet insertion hole; a permanent magnet inserted in the permanent magnet insertion hole; and a plurality of slits formed in an iron core section on the outer side of the permanent magnet insertion hole. The width in the radial direction of a slit thin section of each of the slits between the slit and the rotor iron core outer circumference gradually increases from an inter-electrode side toward a magnetic pole center and changes in a sine wave shape having a peak in the magnetic pole center.
    Type: Grant
    Filed: August 27, 2010
    Date of Patent: November 3, 2015
    Assignee: Mitsubishi Electric Corporation
    Inventors: Koji Yabe, Yoshikazu Fujisue, Hayato Yoshino, Kazuhiko Baba, Tomoaki Oikawa
  • Patent number: 9166462
    Abstract: A rotor of an induction motor according to the present invention is a rotor including a squirrel-cage secondary conductor, wherein the rotor slot is constituted by an outer circumferential slot formed near an outer circumference of the rotor and an inner circumferential slot communicating with the outer circumferential slot and formed inside of the outer circumferential slot, a circumferential width TC of an innermost circumference of the outer circumferential slot is smaller than a circumferential width TD of an outermost circumference of the inner circumferential slot, and a circumferential width of the outer circumferential slot is smaller as the outer circumferential slot approaches to the outer circumference of the rotor.
    Type: Grant
    Filed: October 19, 2010
    Date of Patent: October 20, 2015
    Assignee: Mitsubishi Electric Corporation
    Inventors: Koji Yabe, Hayato Yoshino, Takahiro Tsutsumi, Kazuhiko Baba, Tomoaki Oikawa
  • Publication number: 20150280500
    Abstract: A rotor core includes a plurality of first electromagnetic steel plates that are stacked in an axial direction and a plurality of second electromagnetic steel plates that are stacked in an axial direction at both ends of the electromagnetic steel plate group thereof. The first electromagnetic steel plates are provided therein with magnet insertion holes and first flux barriers. The second electromagnetic steel plates are provided therein with the magnet insertion holes, second flux barriers, and projections that regulate the positions of the magnets. The second electromagnetic steel plates are stacked at at least one of the axial direction ends of the electromagnetic steel plate group including the plurality of first electromagnetic steel plates and are provided at a position overhanging the axial direction end of a stator core.
    Type: Application
    Filed: November 1, 2012
    Publication date: October 1, 2015
    Applicant: Mitsubishi Electric Corporation
    Inventors: Masahiro NIGO, Naohiro OKETANI, Koji YABE, Kazuhiko BABA
  • Publication number: 20150263574
    Abstract: A rotor of a motor includes a rotor core; permanent magnet insertion holes that are formed in an outer circumferential portion of the rotor core along a circumferential direction and in each of which an air gap extending in an outer circumferential direction, is formed in both end portions in a state where a permanent magnet is inserted; and a permanent magnet inserted in each of the permanent magnet insertion holes, wherein a thin portion is formed between the air gap and an outer circumference of the rotor core, rounded corner portions are formed at two locations on an outer circumference side in the air gap, and a radius of curvature of any one of the corner portions is equal to or more than half a width of the air gap in a circumferential direction.
    Type: Application
    Filed: December 12, 2012
    Publication date: September 17, 2015
    Applicant: MITSUBISHI ELECTRIC CORPORATION
    Inventors: Koji Yabe, Naohiro Oketani
  • Publication number: 20150256038
    Abstract: A permanent magnet embedded electric motor includes a slit and a flux barrier. A hole defining portion of a magnet insertion hole includes an extended portion. The extended portion projects toward an interpolar core portion in a rotor core in an area positioned further on an outer side of a circumferential direction with respect to a width-direction end surface of a permanent magnet. (Lb) is larger than (La), and (Lc) is smaller than (Ld), where the (La) represents a distance between the slit and the core outer peripheral surface; the (Lb) represents a distance between the slit and an outer peripheral-side surface of the permanent magnet; the (Lc) represents a shortest distance between the extended portion and the interpolar core portion; and the (Ld) represents a thickness of the permanent magnet.
    Type: Application
    Filed: October 29, 2013
    Publication date: September 10, 2015
    Applicant: Mitsubishi Electric Corporation
    Inventors: Masahiro Nigo, Naohiro Oketani, Koji Yabe, Kazuhiko Baba
  • Publication number: 20150236558
    Abstract: A rotor of an interior permanent magnet motor includes a rotor core having a plurality of magnet insertion holes, a shaft, a plurality of rare-earth magnets, and a pair of magnet fixing members. One surface of the magnet fixing member is provided with a plurality of pairs of tongue-like portions, and the tongue-like portions are inserted into the magnet insertion holes. On each of both sides in a rotary shaft direction, the rare-earth magnets have both end surfaces in a rotor circumferential direction sandwiched by a corresponding pair of tongue-like portions. An interval between the tongue-like portions includes, at a position separated from a base position, an interval that is smaller than the width of the rare-earth magnet in the rotor circumferential direction.
    Type: Application
    Filed: October 2, 2013
    Publication date: August 20, 2015
    Applicant: MITSUBISHI ELECTRIC CORPORATION
    Inventors: Naohiro Oketani, Masahiro Nigo, Kazuhiko Baba, Koji Yabe
  • Publication number: 20150184871
    Abstract: To provide an air conditioner outdoor unit including a casing having an air inlet on a side surface and an air outlet on an upper surface, a heat exchanger that covers the air inlet and is provided inside the casing, a fan that sucks in air from the air inlet and discharges air from the air outlet, and a fan motor provided on a lower side of the fan. The fan motor is set such that an outer diameter D1 thereof is larger than an outer diameter D2 of a fan boss, and an outer periphery thereof is positioned on a center side of the fan motor than a straight line c passing an upper side of a center (for example, a predetermined position a) of the heat exchanger and a side (for example, a predetermined position b) of the fan boss.
    Type: Application
    Filed: June 6, 2013
    Publication date: July 2, 2015
    Inventors: Koji Yabe, Naohiro Oketani, Kazuhiko Baba, Hiroshi Yamanaka, Hironori Yabuuchi
  • Publication number: 20150084444
    Abstract: A mold stator is configured to include a stator core and a mold resin that covers the stator core. A divided-core part includes a yoke part that is arranged coaxially with a rotor that is provided in the stator core, a teeth part that extends from the yoke part in a radially-inward direction, and a teeth distal-end part that is formed at a radially-inward end part of the teeth part. An outer-circumferential flat-surface part is formed on an outer circumferential surface of the yoke part and an outer-circumferential flat-surface part is formed at a position on an outer circumferential surface of the mold stator opposing the flat-surface part of the yoke part.
    Type: Application
    Filed: October 19, 2012
    Publication date: March 26, 2015
    Inventors: Koji Yabe, Naohiro Oketani, Hiroshi Yamanaka, Hironori Yabuuchi, Takayuki Onihashi
  • Patent number: 8937420
    Abstract: A rotor of a permanent magnet embedded motor includes a rotor iron core formed by stacking a predetermined number of magnetic steel sheets punched into predetermined shapes, a plurality of permanent-magnet insertion holes formed along an outer circumferential portion of the rotor iron core and each including permanent-magnet end-portion cavities on its both ends, a plurality of permanent magnets inserted into the permanent-magnet insertion holes, and a plurality of slits formed in the outer-peripheral side iron core portion outside of each permanent-magnet insertion holes, wherein a distance between a first slit present in a radial direction of each of the end portions of the permanent magnets and a second slit, which is adjacent to the first slit and closer to the center of its magnetic pole, is smaller than a distance between those slits other than the first and second slits.
    Type: Grant
    Filed: March 25, 2010
    Date of Patent: January 20, 2015
    Assignee: Mitsubishi Electric Corporation
    Inventors: Koji Yabe, Hayato Yoshino, Kazuhiko Baba
  • Publication number: 20140368081
    Abstract: A rotor of a permanent-magnet embedded motor includes a rotor core having magnet insertion holes along a circumferential direction and a magnet inserted into each of the holes, wherein a gap is formed at opposite ends of a hole at a time of inserting the magnet therein, an outer peripheral face of the core is formed by a first curved surface formed from a magnetic pole center to between poles, with a radial distance from a shaft center of the core being largest at the pole center on the peripheral face, and a second curved surface formed from an interpolar portion toward the pole center to intersect with the first curved surface, with the radial distance from the shaft center being smallest in the interpolar portion on the peripheral face, and wherein a length of the first curved surface is larger than a length of the second curved surface.
    Type: Application
    Filed: December 26, 2011
    Publication date: December 18, 2014
    Applicant: MITSUBISHI ELECTRIC CORPORATION
    Inventors: Koji Yabe, Kazuhiko Baba
  • Patent number: 8912701
    Abstract: The efficiency of an induction motor is improved while suppressing the generation of magnetic flux saturation of a rotor core. In an induction motor, “a magnetic path width of a rotor” which is the product of a circumferential width of a rotor tooth formed in the rotor and the number of rotor teeth is equal to or larger than “a magnetic path width of a stator” which is the product of a circumferential width of a stator tooth formed in the stator and the number of stator teeth.
    Type: Grant
    Filed: March 12, 2013
    Date of Patent: December 16, 2014
    Assignee: Mitsubishi Electric Corporation
    Inventors: Takahiro Tsutsumi, Koji Yabe
  • Publication number: 20140265705
    Abstract: A rotor, constituting an interior permanent magnet motor, includes magnets that are inserted into the rotor, and a rotor core containing magnet insertion pockets to which the magnets are inserted, and, when the magnets are inserted, the magnet insertion pockets are formed to provide openings in areas except both ends of an inner circumferential face, at both ends in a circumferential direction of the magnets.
    Type: Application
    Filed: October 26, 2011
    Publication date: September 18, 2014
    Applicant: MITSUBISHI ELECTRIC CORPORATION
    Inventors: Kazuchika Tsuchida, Masahiro Nigo, Koji Yabe, Tomoaki Oikawa
  • Publication number: 20140232231
    Abstract: A rotor of an interior permanent magnet motor includes a rotor core; permanent magnet insertion holes formed in an outer circumferential portion of the rotor core along a circumferential direction; a permanent-magnet end-portion air gap formed in each of both end portions of each permanent magnet insertion hole; a permanent magnet inserted in each permanent magnet insertion hole; and slits formed in an outer circumferential core portion on an outer side in a radial direction with respect to each permanent magnet insertion hole, wherein a width of a core present between the permanent-magnet end-portion air gap and the slit and a width of a core present between the slits are such that a width of a core gradually increases as the core is closer to a magnet pole center from the interpolar line.
    Type: Application
    Filed: October 24, 2011
    Publication date: August 21, 2014
    Applicant: MITSUBISHI ELECTRIC CORPORATION
    Inventors: Koji Yabe, Kazuhiko Baba
  • Publication number: 20140232230
    Abstract: A permanent magnet embedded motor includes a rotor and permanent magnets. The outer circumferential surface of the rotor is formed by divided outer circumferential surfaces divided at equal angle intervals in a circumferential direction corresponding to permanent magnets. The divided outer circumferential surface is formed by a first curved surface, a radial direction distance of which from a rotor axis is maximized in a circumferential direction center of divided outer circumferential surface and second curved surfaces formed from the circumferential direction both ends to the circumferential direction center and crossing the first curved surface. The second curved surfaces are formed by arcuate surfaces each having the rotor axis as a central axis. A distance between both ends of the first curved surface is smaller than the width of a permanent magnet in a direction orthogonal to a radial direction in the circumferential direction center.
    Type: Application
    Filed: July 15, 2011
    Publication date: August 21, 2014
    Applicant: MITSUBISHI ELECTRIC CORPORATION
    Inventors: Koji Yabe, Hayato Yoshino, Kazuhiko Baba
  • Patent number: 8740584
    Abstract: An induction motor includes a stator having a winding to be inserted to a plurality of stator slots formed along an inner circumferential edge of a stator iron core; and a rotor placed inside of the stator via a gap, the rotor includes a plurality of double squirrel-cage rotor slots formed along an outer circumferential edge of the rotor iron core and filled with conductive material and at least three air hole parts provided around a rotating shaft hole of the rotor iron core to which the rotating shaft is fitted and having an opening which is open to the rotating shaft hole; and an inner diameter part of the end ring which short circuits both edges of the conductive material filled to the double squirrel-cage rotor slot is placed to be adjacent to the air hole part in at least the end ring of one side.
    Type: Grant
    Filed: August 5, 2008
    Date of Patent: June 3, 2014
    Assignee: Mitsubishi Electric Corporation
    Inventors: Hayato Yoshino, Koji Yabe, Kazuhiko Baba, Tomoaki Oikawa, Takahiro Tsutsumi, Yoshikazu Fujisue
  • Patent number: 8723388
    Abstract: The efficiency of an induction motor is improved while suppressing the generation of magnetic flux saturation of a rotor core. In an induction motor, “a magnetic path width of a rotor” which is the product of a circumferential width of a rotor tooth formed in the rotor and the number of rotor teeth is equal to or larger than “a magnetic path width of a stator” which is the product of a circumferential width of a stator tooth formed in the stator and the number of stator teeth.
    Type: Grant
    Filed: September 15, 2011
    Date of Patent: May 13, 2014
    Assignee: Mitsubishi Electric Corporation
    Inventors: Takahiro Tsutsumi, Koji Yabe
  • Patent number: 8714948
    Abstract: An object is to provide a permanent magnet motor that highly reduces torque fluctuation, thereby reducing noise and vibration. The permanent magnet motor may be formed as follows: a length D of a permanent magnet 8 in a longitudinal direction is the same as or longer than a width A between sides of the magnetic pole tooth 3 in the circumferential direction in an end portion of the magnetic pole tooth 3, and a distance C between tip portions of a pair of the first slits 13a and 13b within the same pole is smaller than the width A between the sides of the magnetic pole tooth 3 in the circumferential direction in the end portion of the magnetic pole tooth 3. The permanent magnet motor, thus formed, may be characterized in that cut surfaces 12 face the first slits 13a and 13b.
    Type: Grant
    Filed: February 26, 2007
    Date of Patent: May 6, 2014
    Assignee: Mitsubishi Electric Corporation
    Inventors: Kazuhiko Baba, Hayato Yoshino, Koji Yabe, Masahiro Nigo, Koji Masumoto, Tomoaki Oikawa, Yoshio Takita
  • Patent number: 8659203
    Abstract: The efficiency of an induction motor is improved while suppressing the generation of magnetic flux saturation of a rotor core. In an induction motor, “a magnetic path width of a rotor” which is the product of a circumferential width of a rotor tooth formed in the rotor and the number of rotor teeth is equal to or larger than “a magnetic path width of a stator” which is the product of a circumferential width of a stator tooth formed in the stator and the number of stator teeth.
    Type: Grant
    Filed: September 15, 2011
    Date of Patent: February 25, 2014
    Assignee: Mitsubishi Electric Corporation
    Inventors: Takahiro Tsutsumi, Koji Yabe
  • Patent number: 8610327
    Abstract: The efficiency of an induction motor is improved while suppressing the generation of magnetic flux saturation of a rotor core. In an induction motor, “a magnetic path width of a rotor” which is the product of a circumferential width of a rotor tooth formed in the rotor and the number of rotor teeth is equal to or larger than “a magnetic path width of a stator” which is the product of a circumferential width of a stator tooth formed in the stator and the number of stator teeth.
    Type: Grant
    Filed: September 15, 2011
    Date of Patent: December 17, 2013
    Assignee: Mitsubishi Electric Corporation
    Inventors: Takahiro Tsutsumi, Koji Yabe