Patents by Inventor Kazuhiko Baba

Kazuhiko Baba 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: 9369015
    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: Grant
    Filed: July 15, 2011
    Date of Patent: June 14, 2016
    Assignee: Mitsubishi Electric Corporation
    Inventors: Koji Yabe, Hayato Yoshino, Kazuhiko Baba
  • Patent number: 9362791
    Abstract: A magnet constituting a magnetic pole of a rotor includes an annular ferrite bond magnet provided on an outer circumference of a rotation shaft and a plurality of sintered ferrite magnets arranged on an outer circumference of the ferrite bond magnet. The ferrite bond magnet includes, on an outer circumferential surface thereof, curved concave portions convexed toward a side of the rotation shaft. The sintered ferrite magnets are arranged on the curved concave portions, and include a surface on a side of the stator that is formed in a curved convex shape toward the side of the stator, and a center portion whose thickness with respect to the circumferential direction is formed to be larger than a thickness of an edge portion, wherein magnetization direction is oriented in polar anisotropy.
    Type: Grant
    Filed: December 27, 2011
    Date of Patent: June 7, 2016
    Assignee: Mitsubishi Electric Corporation
    Inventors: Atsushi Matsuoka, Kazuhiko Baba
  • Publication number: 20160126798
    Abstract: The motor includes a motor body to rotate a shaft by generating a rotating magnetic field; a bearing supporting the shaft; and a bracket being electrically non-conductive, surrounding an outer periphery of the bearing, and supporting the bearing, wherein the bracket is not in contact with any member formed of conductive material at an outer periphery of the bracket.
    Type: Application
    Filed: July 3, 2013
    Publication date: May 5, 2016
    Applicant: MITSUBISHI ELECTRIC CORPORATION
    Inventors: Yukihiko KAWANORI, Hironori YABUUCHI, Nobuaki MIYAKE, Kazuhiko BABA, Tomoki HAYASHI
  • Publication number: 20160087498
    Abstract: A 10-pole/9-slot synchronous motor includes nine teeth that are divided into three phases, each having three adjacent teeth. A stator iron core is configured such that a value obtained by dividing b by a is larger than 0.5 where the a is a width of a teeth tip, which is provided on an inner diameter side of a tooth of the teeth formed on the stator iron core, from a base portion between the teeth tip and the tooth to a circumferential end of the teeth tip and the b is a thickness of the teeth tip from the base portion to an inner-diameter side surface of the teeth tip.
    Type: Application
    Filed: May 20, 2014
    Publication date: March 24, 2016
    Inventors: Atsushi MATSUOKA, Kazuhiko BABA, Hiroki ASO, Yuto URABE
  • Patent number: 9287759
    Abstract: In an induction motor, when dimensions of respective elements of a rotor slot are defined as TB: a shortest distance between a center side of an inner circumferential slot and an outer circumference of the rotor; TC: a circumferential width of an innermost circumference of an outer circumferential slot; TD: a circumferential width of an outermost circumference of the inner circumference slot; and TE: a shortest distance between an end side of the inner circumferential slot and the outer circumference of the rotor, and when dimensions of respective elements of a stator iron core are defined as TF: a width of teeth; TG: a width of a teeth tip end; and TH: a width of a slot opening part, the dimensions of the respective elements of the rotor slot and the dimensions of the respective elements of the stator iron core satisfy the following relationships: TF/(TG+TH)×TD/2?TB?TD/2; and TF/(TG+TH)×TD/2?TE?TD/2.
    Type: Grant
    Filed: December 6, 2010
    Date of Patent: March 15, 2016
    Assignee: Mitsubishi Electric Corporation
    Inventors: Koji Yabe, Hayato Yoshino, Takahiro Tsutsumi, Kazuhiko Baba, Tomoaki Oikawa
  • Publication number: 20160028278
    Abstract: Provided is an interior permanent magnet motor, including: a plurality of permanent magnets respectively inserted into a plurality of magnet accommodating holes formed in a rotator core of a rotator. In the magnet accommodating hole, a pair of minute projecting portions, a pair of large projecting portions, and a pair of demagnetizing field recesses are formed. The permanent magnet is sandwiched by a corresponding pair of minute projecting portions. The minute projecting portion is protruded radially inward to be in surface-contact with a corresponding end surface of the permanent magnet. The large projecting portion is formed on an outer side of the minute projecting portion, and is extended to an inner defining line side of the magnet accommodating hole. A height dimension (Ta) of the large projecting portion is larger than a height dimension (Tb) of the minute projecting portion.
    Type: Application
    Filed: March 14, 2013
    Publication date: January 28, 2016
    Applicant: MITSUBISHI ELECTRIC CORPORATION
    Inventors: Kazuhiko BABA, Koji YABE, Tomoaki OIKAWA
  • Publication number: 20160006301
    Abstract: A synchronous motor is configured such that a rotor, in which permanent magnets having poles are provided at an equiangular interval in a circumferential direction, with magnetic poles with different polarities being alternately provided, is provided to face a stator, in which nine teeth are formed at an equiangular interval in a circumferential direction, and the tip width of the central tooth of each phase among the teeth of each phase grouped into three phases with each phase including three adjacent teeth is larger than 32° and smaller than 40°.
    Type: Application
    Filed: January 24, 2013
    Publication date: January 7, 2016
    Inventors: Atsushi MATSUOKA, Kazuhiko BABA, Hiroki ASO, Yuto URABE
  • Publication number: 20150372548
    Abstract: A rotor outer peripheral surface includes first arcs and second arcs. The first arc is positioned in a magnetic pole center portion. The second arc is positioned in an inter-pole portion. The first arc bulges toward a radially outer side to a higher degree than the second arc. An air gap is varied in a manner of being increased as approaching from each of the magnetic pole center portions to the adjacent inter-pole portions. A hole defining portion of a magnet insertion hole on the radially outer side has a curvature of a third arc, and a hole defining portion of the magnet insertion hole on a radially inner side has a curvature of a fourth arc. An opening angle of a tooth tip portion, an opening angle of the first arc, and an opening angle of the third arc coincide with each other.
    Type: Application
    Filed: February 14, 2013
    Publication date: December 24, 2015
    Applicant: Mitsubishi Electric Corporation
    Inventors: Masahiro NIGO, Kazuhiko BABA, Kazuchika TSUCHIDA
  • 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
  • Publication number: 20150318743
    Abstract: An interior permanent magnet motor capable of increasing an output of a motor without reducing torque by increasing demagnetization resistance. The interior permanent magnet motor includes a rotator including a rotator core, and a stator. The rotator core includes a plurality of magnet accommodating holes and a plurality of permanent magnets. The thickness in the short-side direction of each of the magnet accommodating holes is minimum at the center portion of the magnetic pole, and is gradually increased toward the radially outer side of the rotator core. At least the thickness in the short-side direction of the permanent magnet at the center portion of the magnetic pole is equal to the thickness in the short-side direction of the magnet accommodating hole at the center portion of the magnetic pole.
    Type: Application
    Filed: September 20, 2013
    Publication date: November 5, 2015
    Applicant: MITSUBISHI ELECTRIC CORPORATION
    Inventors: Kazuhiko BABA, Masahiro NIGO, Kazuchika TSUCHIDA
  • Publication number: 20150318764
    Abstract: A permanent magnet buried type electric motor includes a rotator having a rotator core and a stator. The rotator core includes: a plurality of magnet accommodating holes formed as many as the number of poles; a plurality of permanent magnets; air holes through which a coolant and a refrigerant oil pass; and a fastening hole. The magnet accommodating hole is formed into a shape that projects toward a radially inner side and is recessed toward a radially outer side. The air hole portions and the fastening holes are arranged so as to be alternately positioned. The air hole portion is formed into such a shape that includes a portion extending in an arc shape along an outer peripheral surface of a rotary shaft in a circumferential direction of the rotator core so that an area of the air hole portion is larger than an area of the fastening hole.
    Type: Application
    Filed: December 21, 2012
    Publication date: November 5, 2015
    Applicant: Mitsubishi Electric Corporation
    Inventors: Kazuhiko BABA, Masahiro NIGO, Kazuchika TSUCHIDA
  • 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: 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: 20150139830
    Abstract: In a permanent-magnet-embedded electric motor, at the distal ends of base sections of teeth sections of a stator core, increased magnetic-resistance sections, which have magnetic resistance larger than magnetic resistance of the base sections, are provided. Given that a minimum interval in the circumferential direction between the base sections adjacent to each other is represented as La, an interval of a minimum gap between the teeth sections adjacent to each other is represented as Lb, and an interval of a gap between a rotor and a stator is represented as Lg, a relation of La>2Lg>Lb holds. Due to such a configuration, it is possible to provide the electric motor that does not spoil a magnetic characteristic of the rotor and that is excellent in a demagnetization characteristic.
    Type: Application
    Filed: June 26, 2012
    Publication date: May 21, 2015
    Applicant: MITSUBISHI ELECTRIC CORPORATION
    Inventors: Masahiro Nigo, Kazuhiko Baba, Kazuchika Tsuchida
  • Publication number: 20150084468
    Abstract: A rotor for a permanent-magnet-embedded electric motor includes slit holes each axially formed near opposite ends of a magnetic pole between an outer peripheral face of a rotor core and a magnet insertion hole, and forming a symmetrical shape in an approximately truncated chevron shape along the outer peripheral face of the rotor core, based on a centerline of each of the magnetic poles, wherein a thickness of each of permanent magnets is set to be twice or more of an air gap, a width of a shortest magnetic path in which a distance between the slit hole and the permanent magnet becomes shortest is set to be twice or more of the air gap, and an inclination of the slit hole with respect to a width direction of the permanent magnet orthogonal to a radial direction is set to be in a range from 0 to 30 degrees.
    Type: Application
    Filed: January 30, 2012
    Publication date: March 26, 2015
    Applicant: MITSUBISHI ELECTRIC CORPORATION
    Inventors: Masahiro Nigo, Kazuhiko Baba, Kazuchika Tsuchida
  • Publication number: 20150028708
    Abstract: A drive device driving a power converter that includes a switching element formed from a wide bandgap semiconductor, includes a PWM-signal output unit that generates a drive signal that drives the switching element with PWM; an on-speed reducing unit that, when the switching element is changed from off to on, reduces a change rate of the drive signal; and an off-speed improving unit that, when the switching element is changed from on to off, draws charge from the switching element at a high speed and with a charge drawing performance higher than that at a time when the switching element is changed from off to on.
    Type: Application
    Filed: December 27, 2011
    Publication date: January 29, 2015
    Applicant: MITSUBISHI ELECTRIC CORPORATION
    Inventors: Atsushi Matsuoka, Kazuhiko Baba