Patents by Inventor Motonobu Iizuka

Motonobu Iizuka 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: 9203277
    Abstract: In a permanent magnet pump motor comprising a stator and a rotor, a permanent magnet is used for the rotor; and the rotor has a shaft end portion to be mounted with a joint shaft for rotor insertion and bearing brackets for housing therein bearings for supporting the both ends of the rotor. The bearing brackets have cavities through which a rotor shaft and the joint shaft can pass.
    Type: Grant
    Filed: February 19, 2013
    Date of Patent: December 1, 2015
    Assignee: Hitachi, Ltd.
    Inventors: Daisuke Kori, Motonobu Iizuka, Atsushi Fukunaga
  • Patent number: 9054568
    Abstract: A permanent magnet rotating electric machine includes a rotor and a stator. The rotor includes: a permanent magnet forming a single pole within a rotor core of the rotor, the permanent magnet being divided into two divided permanent magnets; a connecting portion assuming an electrical steel sheet disposed between the two divided permanent magnets; and magnet insertion holes in which the permanent magnets are inserted. In the rotor, the magnet insertion holes are shaped to include: air gaps at both end portions in a width direction of the permanent magnet, each air gap being formed between a surface of the permanent magnet extending perpendicularly to the magnetization direction and a surface of the electrical steel sheet facing the surface of the permanent magnet; a shoulder portion disposed on the facing surface; and another air gap extending toward a rotor outside diameter side and the magnetic pole center side.
    Type: Grant
    Filed: February 14, 2013
    Date of Patent: June 9, 2015
    Assignee: Hitachi, Ltd.
    Inventors: Daisuke Kori, Motonobu Iizuka, Atsushi Fukunaga
  • Publication number: 20150035471
    Abstract: A field winding type synchronous motor comprises a stator, a rotor with field windings, a brushless exciter, and a rectification circuit rectifying an output of the brushless exciter. A first circuit in parallel with the field windings includes a discharge resistor and a first switching device with a backward diode. The discharge resistor and the first switching device are connected in series. A second switching device is provided in one of the DC lines connecting the first circuit and the rectification circuit. The first switching device is controlled by a potential obtained by resistor dividing of an induced voltage in the field windings and a connection from the potential via a diode to anode adjacent to the rectification circuit on the one of the DC lines with the second switching device thereon. The second switching device is closed in a synchronous speed.
    Type: Application
    Filed: July 30, 2014
    Publication date: February 5, 2015
    Applicant: Hitachi, Ltd.
    Inventors: Daisuke KORI, Motonobu IIZUKA, Takayuki KOYAMA
  • Publication number: 20140252910
    Abstract: There is provided an induction machine having a squirrel-cage rotor, the rotor including: a rotor core; a plurality of rotor slots formed on the rotor core and aligned circumferentially at a predetermined interval; a plurality of rotor bars inserted into one of the plurality of rotor slots; and a plurality of rotor slits formed adjacent to the plurality of rotor slots on an outer circumferential side of the rotor core. The each rotor slit is formed as a hollow such that a cross sectional shape thereof is distinguished into three parts of a slit outer circumferential part, a slit intermediate part, and a slit inner circumferential part. A circumferential width of the each rotor slit on an innermost circumferential side is larger than that on an outermost circumferential side. A circumferential width of the slit intermediate part increases from an outer circumferential side toward an inner circumferential side.
    Type: Application
    Filed: March 6, 2014
    Publication date: September 11, 2014
    Applicant: Hitachi, Ltd.
    Inventors: Naoki KUNIHIRO, Kazuo NISHIHAMA, Motonobu IIZUKA, Kenichi SUGIMOTO, Masanori SAWAHATA, Akiyoshi KOMURA
  • Patent number: 8669473
    Abstract: A dry mica tape includes a base material, a binder resin layer A formed on the base material and including an epoxy resin and an accelerator, a mica paper layer formed in contact with the binder resin layer A, and a binder resin layer B formed in contact with the mica paper layer, including an epoxy resin, and providing a cured resin with a higher glass transition point than that of a cured resin of an impregnating varnish only by reacting with an impregnating varnish including an epoxy resin impregnated into the dry mica tape wound around a conductor.
    Type: Grant
    Filed: August 9, 2011
    Date of Patent: March 11, 2014
    Assignee: Hitachi, Ltd.
    Inventors: Kenji Ikeda, Hisashi Morooka, Motonobu Iizuka, Yoshihiro Haraguchi, Naohiro Hiruta, Shoichi Maruyama
  • Patent number: 8653703
    Abstract: The permanent magnet rotating electric machine comprising a stator with a stator coil wound on a stator iron core, a rotor with a plurality of permanent magnets disposed in the circumferential direction in a rotor iron core, which is disposed opposite to the stator iron core of the stator with a predetermined spacing therebetween and is fixed to a shaft, a water-cooling unit disposed around the outer circumference of the stator iron core, and a fan fixed to the shaft on the same side as at least one axial end of the rotor iron core to circulate cooling air in the permanent magnet rotating electric machine; further comprising ventilation paths, through which the cooling air flows, formed around the outer circumference of the water-cooling unit; wherein after the cooling air has been circulated by the fan in the machine for cooling, the cooling air is led to the ventilation paths to perform heat exchange between the cooling air flowing in the ventilation paths and the water-cooling unit, after which the cool
    Type: Grant
    Filed: February 17, 2011
    Date of Patent: February 18, 2014
    Assignee: Hitachi, Ltd.
    Inventors: Daisuke Kori, Shogo Serita, Tetsuo Fujigaki, Masaaki Endo, Yoshihiro Yasui, Ai Nagano, Mamoru Kimura, Motonobu Iizuka, Akiyoshi Komura
  • Publication number: 20140001912
    Abstract: An electrical rotating machine includes: a rotating shaft; a rotor, equipped with permanent magnets, and formed to rotate with the rotating shaft, a stator disposed in opposition on an outside-diametral side and via a clearance with respect to the rotor; and anti-demagnetization conductors extending in the axial direction of the shaft, the conductors each being disposed inside the rotor, wherein: the anti-demagnetization conductors are provided in pairs of two for each of magnetic poles of the rotor; the two anti-demagnetization conductors forming a pair are electrically interconnected; and, inside the rotor, the two paired anti-demagnetization conductors are disposed at different-polarity sides of two corresponding permanent magnets in a circumferential direction of the rotor, the different-polarity sides each being more adjacent to the circumferential direction of the rotor than to an end portion of one of the two corresponding permanent magnets existing close to each other in one magnetic pole.
    Type: Application
    Filed: June 27, 2013
    Publication date: January 2, 2014
    Inventors: Mamoru KIMURA, Akiyoshi KOMURA, Daisuke KORI, Tetsuo FUJIGAKI, Motonobu IIZUKA
  • Publication number: 20130340256
    Abstract: A bearing replacement method for a rotating machine of the present invention includes the steps of: when at least one bearing of a rotating machine is to be replaced with a new one, mounting at an end portion of the rotating machine a plurality of bendable arms for removing a first bearing covering part, a power supply unit outer frame, and a slipring, respectively; removing with the arms the first bearing covering part, the power supply unit outer frame, and the slipring, respectively; and thereafter replacing the at least one bearing with a new one.
    Type: Application
    Filed: June 18, 2013
    Publication date: December 26, 2013
    Inventors: Osamu TSUCHITANI, Motonobu IIZUKA, Shuji MIZUTANI, Tetsuo FUJIGAKI, Masaaki ENDO, Yoshihiro YASUI, Shogo SERITA, Masakazu SHINDEN
  • Patent number: 8546991
    Abstract: A synchronous generator 1 including a rotor having a field winding placed in the slots thereof and a stator having an armature winding placed in the slots thereof, wherein the value of the number of slots per two poles in stator minus the number of slots per two poles in rotor is equal to or greater than +9, or equal to or smaller than ?9.
    Type: Grant
    Filed: July 22, 2009
    Date of Patent: October 1, 2013
    Assignee: Hitachi, Ltd.
    Inventors: Masanori Sawahata, Kazuo Nishihama, Hiroyuki Mikami, Tetsuo Fujigaki, Motonobu Iizuka, Shuji Mizutani
  • Patent number: 7994666
    Abstract: A permanent magnet electrical rotating machine having a permanent magnet rotor and a stator, wherein: a plurality of permanent magnets are disposed in a rotor iron core of the permanent magnet rotor along a periphery of the rotor iron core, polarities thereof being alternately changed; a cooling airflow channel is formed between each pair of adjacent opposite poles on the rotor iron core; and the cooling airflow channel has an approximately trapezoidal shape on an outer periphery side of the rotor iron core; and extends from an end on a central side in a radial direction of the approximately trapezoidal shape to a radial center.
    Type: Grant
    Filed: November 21, 2007
    Date of Patent: August 9, 2011
    Assignee: Hitachi, Ltd.
    Inventors: Daisuke Kori, Tetsuo Fujigaki, Shuji Aizawa, Motonobu Iizuka, Yasushi Iwai, Hiroyuki Mikami, Mamoru Kimura
  • Patent number: 7847456
    Abstract: A permanent magnet electrical rotating machine having a permanent magnet rotor and a stator, wherein: a plurality of permanent magnets are disposed in a rotor iron core of the permanent magnet rotor along a periphery of the rotor iron core, polarities thereof being alternately changed; a cooling airflow channel is formed between each pair of adjacent opposite poles on the rotor iron core; and the cooling airflow channel has an approximately trapezoidal shape on an outer periphery side of the rotor iron core; and extends from an end on a central side in a radial direction of the approximately trapezoidal shape to a radial center.
    Type: Grant
    Filed: April 5, 2010
    Date of Patent: December 7, 2010
    Assignee: Hitachi, Ltd.
    Inventors: Daisuke Kori, Tetsuo Fujigaki, Shuji Aizawa, Motonobu Iizuka, Yasushi Iwai, Hiroyuki Mikami, Mamoru Kimura
  • Publication number: 20100194221
    Abstract: A permanent magnet electrical rotating machine having a permanent magnet rotor and a stator, wherein: a plurality of permanent magnets are disposed in a rotor iron core of the permanent magnet rotor along a periphery of the rotor iron core, polarities thereof being alternately changed; a cooling airflow channel is formed between each pair of adjacent opposite poles on the rotor iron core; and the cooling airflow channel has an approximately trapezoidal shape on an outer periphery side of the rotor iron core; and extends from an end on a central side in a radial direction of the approximately trapezoidal shape to a radial center.
    Type: Application
    Filed: April 5, 2010
    Publication date: August 5, 2010
    Inventors: Daisuke KORI, Tetsuo Fujigaki, Shuji Aizawa, Motonobu Iizuka, Yasushi Iwai, Hiroyuki Mikami, Mamoru Kimura
  • Publication number: 20100026008
    Abstract: A synchronous generator 1 including a rotor having a field winding placed in the slots thereof and a stator having an armature winding placed in the slots thereof, wherein the value of the number of slots per two poles in stator minus the number of slots per two poles in rotor is equal to or greater than +9, or equal to or smaller than ?9.
    Type: Application
    Filed: July 22, 2009
    Publication date: February 4, 2010
    Applicant: HITACHI, LTD.
    Inventors: Masanori SAWAHATA, Kazuo NISHIHAMA, Hiroyuki MIKAMI, Tetsuo FUJIGAKI, Motonobu IIZUKA, Shuji MIZUTANI
  • Publication number: 20100026145
    Abstract: In a sealed type electric rotating machine, in which a cooling medium inflows from both end sides of a rotating shaft of a claw-pole type rotor, a cooling medium having passed through a heat exchanging part divides into one on an exhaust side and one on an intake air side to be used again for cooling of the claw-pole type rotor and a stator. On the exhaust side, a cooling medium being high in temperature as compared with that on the intake air side performs cooling, and the rotor and the stator are made higher in temperature on the exhaust side than on the intake air side. In order to level temperature profiles of the claw-pole type rotor and the stator in an axial direction, a partition, which cuts off an axial duct, is provided toward the exhaust side relative to a center in the axial direction.
    Type: Application
    Filed: July 28, 2009
    Publication date: February 4, 2010
    Applicant: HITACHI, LTD.
    Inventors: Yasushi IWAI, Kengo IWASHIGE, Motonobu IIZUKA, Tetsuo FUJIGAKI, Mamoru KIMURA, Daisuke KORI
  • Patent number: 7619332
    Abstract: A permanent magnet type electric rotating machine comprises a stator having a distributed winding and a permanent magnet rotor, wherein the permanent magnet rotor is provided with a wind passage in an axial direction thereof.
    Type: Grant
    Filed: September 30, 2005
    Date of Patent: November 17, 2009
    Assignee: Hitachi, Ltd.
    Inventors: Mamoruo Kimura, Kazumasa Ide, Motonobu Iizuka, Shuji Mizutani, Tetsuo Fujigaki, Kengo Iwashige, Hisato Tagawa, Yusaku Maruno
  • Publication number: 20080129129
    Abstract: A permanent magnet electrical rotating machine having a permanent magnet rotor and a stator, wherein: a plurality of permanent magnets are disposed in a rotor iron core of the permanent magnet rotor along a periphery of the rotor iron core, polarities thereof being alternately changed; a cooling airflow channel is formed between each pair of adjacent opposite poles on the rotor iron core; and the cooling airflow channel has an approximately trapezoidal shape on an outer periphery side of the rotor iron core; and extends from an end on a central side in a radial direction of the approximately trapezoidal shape to a radial center.
    Type: Application
    Filed: November 21, 2007
    Publication date: June 5, 2008
    Inventors: Daisuke Kori, Tetsuo Fujigaki, Shuji Aizawa, Motonobu Iizuka, Yasushi Iwai, Hiroyuki Mikami, Mamoru Kimura
  • Publication number: 20060071568
    Abstract: A permanent magnet type electric rotating machine comprises a stator having a distributed winding and a permanent magnet rotor, wherein the permanent magnet rotor is provided with a wind passage in an axial direction thereof.
    Type: Application
    Filed: September 30, 2005
    Publication date: April 6, 2006
    Inventors: Mamoruo Kimura, Kazumasa Ide, Motonobu Iizuka, Shuji Mizutani, Tetsuo Fujigaki, Kengo Iwashige, Hisato Tagawa, Yusaku Maruno