Patents by Inventor Masashi Kitamura

Masashi Kitamura 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: 20080019850
    Abstract: The present invention provides a compact electric motor, thus ensuring improved in-vehicle mountability. A pump is driven by an electric motor. The pump has a coil 14 disposed in a ring form around and along a stator core 13. The stator core 13 has a plurality of claw magnetic poles which extend alternately from both ends of one member of the stator core 13 toward the end of the other member thereof. The electric motor drives the pump by rotating a rotor 16 disposed to face the inner periphery of the stator core 13 as the coil 14 is energized. The present invention provides a compact electric pump with no coil ends, thus ensuring improved in-vehicle mountability. Further, the present invention permits efficient cooling of the electric motor adapted to discharge a cooling medium. Still further, the present invention permits the use of a stator core made from a compressed powder core by molding with resin. In addition, the molded portion also serves as a partition separating pump and motor units.
    Type: Application
    Filed: July 18, 2007
    Publication date: January 24, 2008
    Applicant: Hitachi, Ltd.
    Inventors: Fumio TAJIMA, Masashi Kitamura, Yuji Enomoto, Yuji Nomoto, Kenya Takarai
  • Publication number: 20080018289
    Abstract: A single-phase permanent magnet motor control apparatus, in particular, a low price, flat output torque, low vibration, low noise single-phase permanent magnet motor control apparatus, and a fan and pump using such a single-phase permanent magnet motor control apparatus are provided. In a single-phase permanent magnet motor control apparatus for driving a single-phase permanent magnet motor by using a DC power supply, a converter for converting DC to AC, and a control circuit for controlling the converter, a motor current measuring unit, a terminal voltage measuring unit, a correction unit for correcting an impedance drop in motor constants, and a calculation unit for finding an induced voltage to be obtained by control are included, and a polarity of a terminal voltage is determined on the basis of a value of the found induced voltage.
    Type: Application
    Filed: July 19, 2007
    Publication date: January 24, 2008
    Inventors: Fumio Tajima, Shigeru Kakugawa, Masashi Kitamura, Shoichi Kawamata, Hiroshi Kanazawa, Takayuki Koyama, Shoji Ohiwa, Osamu Sekiguchi
  • Publication number: 20080018194
    Abstract: A single-phase claw-pole type motor comprises a stator, which comprises a claw-pole type stator core and toroidally-wound single-phase stator windings, and a rotor that has alternate polarities, wherein a concave part or a convex part is provided on an air-gap surface of claws of the stator core. In addition, the stator core may be configured by compacting magnetic powder, and the single-phase claw-pole type motor may be driven by a converter that converts a direct current to an alternate current according to a position of the rotor.
    Type: Application
    Filed: July 20, 2007
    Publication date: January 24, 2008
    Inventors: Shigeru KAKUGAWA, Fumio Tajima, Masashi Kitamura, Yuji Enomoto, Motoya Ito, Ryoso Masaki, Shoji Ohiwa, Chio Ishihara
  • Publication number: 20080018196
    Abstract: A claw teeth type electric rotary machine comprises a stator including an annular core with claws formed from a powder core and an annular coil installed inside the annular core, and a rotor rotatably positioned inside the stator. An inner edge of the annular core is provided with plural claw poles which are protruded at a predetermined interval in a circumferential direction and extended in an axial direction of the annular core so as to alternately meshes with each other. The stator comprises the annular core with claws, the annular coil, and a molded nonmagnetic potting material filled between the annular core with claws and annular coil, so that the annular core with claws and annular coil are integrated with the molded potting non-magnetic material.
    Type: Application
    Filed: July 24, 2007
    Publication date: January 24, 2008
    Inventors: Yuji Enomoto, Motoya Ito, Masashi Kitamura, Ryoso Masaki, Katsuyuki Yamazaki, Shoji Ohiwa, Yasuaki Motegi, Kazuo Asaka, Chio Ishihara
  • Publication number: 20080018195
    Abstract: The present invention realizes reduction in vibration and noise while utilizing reluctance torque. A rotating electrical machine of the present invention includes: a rotor in which a plurality of permanent magnets are disposed in a cylindrical surface coaxial with a rotary shaft; and a stator having a annular stator core disposed coaxially with the rotary shaft, and a annular coil for magnetizing the stator core. The stator core has a annular part covering the annular coil, a plurality of claws disposed at equal intervals in an inner radius surface of the annular part and extending in the axial direction, and a plurality of magnetic gaps formed between the neighboring claws. The number of the claws is equal to the number of permanent magnets, and magnet flux in a direction orthogonal to a center axis direction of the magnetic pole of the permanent magnet at right angles in electric angle is larger than magnetic flux in the center axis direction generated between the neighboring permanent magnets.
    Type: Application
    Filed: July 24, 2007
    Publication date: January 24, 2008
    Inventors: Masashi Kitamura, Fumio Tajima, Shigeru Kakugawa, Yuji Enomoto, Motoya Ito, Ryoso Masaki, Shoji Ohiwa, Chio Ishihara
  • Publication number: 20080001483
    Abstract: The present invention provides a cylindrical linear motor that can develop great thrust and reduce thrust pulsations. The cylindrical linear motor includes a stator 1 and a movable element 10 disposed via a clearance with respect to the stator 1 and movable rectilinearly with respect to the stator 1. The stator 1 includes a stator core 3 having stator salient poles 3b, and a three-phase stator coil winding 2 inserted within the slots formed in the stator core 3. The movable element 10 has a plurality of permanent magnets 11 fixed to a movable element core 12. The cylindrical linear motor is constructed so that when the stator salient poles 3b are pitched at ?s and the permanent magnets 11 are pitched at ?p, a relationship of 3/4<?p/s<3/2 is established.
    Type: Application
    Filed: June 25, 2007
    Publication date: January 3, 2008
    Applicant: Hitachi, Ltd.
    Inventors: Masashi Kitamura, Fumio Tajima, Yusuke Akami, Noriyuki Utsumi, Ken Nakamura, Kazuaki Shibahara
  • Publication number: 20070222330
    Abstract: The stator core of a motor comprises an annular back core, and a plurality of tees created separately from the back core and secured onto the inner periphery of the back core. A stator coil is wound on each of the tees by a distributed or concentrated winding method. The stator core and stator coil are formed by molding.
    Type: Application
    Filed: May 31, 2007
    Publication date: September 27, 2007
    Applicant: HITACHI, LTD.
    Inventors: Toshiyuki INNAMI, Mitsuaki MIRUMACHI, Osamu KOIZUMI, Masamichi YAGAI, Masashi KITAMURA, Takashi ISHIGAMI
  • Patent number: 7242128
    Abstract: The stator core of a motor comprises an annular back core, and a plurality of tees created separately from the back core and secured onto the inner periphery of the back core. A stator coil is wound on each of the tees by a distributed or concentrated winding method. The stator core and stator coil are formed by molding.
    Type: Grant
    Filed: May 25, 2005
    Date of Patent: July 10, 2007
    Assignee: Hitachi, Ltd.
    Inventors: Toshiyuki Innami, Mitsuaki Mirumachi, Osamu Koizumi, Masamichi Yagai, Masashi Kitamura, Takashi Ishigami
  • Publication number: 20070085436
    Abstract: A permanent magnet rotating electric machine comprises a stator having stator windings wound round a stator iron core and a permanent magnet rotor having a plurality of inserted permanent magnets in which the polarity is alternately arranged in the peripheral direction in the rotor iron core. The rotor iron core of the permanent magnets is composed of magnetic pole pieces, auxiliary magnetic poles, and a stator yoke, and furthermore has concavities formed on the air gap face of the magnetic pole pieces of the rotor iron core of the permanent magnets, gently tilting from the central part of the magnetic poles to the end thereof. In a permanent magnet rotating electric machine, effects of iron loss are reduced, and an electric car using highly efficient permanent magnet rotating electric machine are realized.
    Type: Application
    Filed: December 15, 2006
    Publication date: April 19, 2007
    Applicant: HITACHI LTD.
    Inventors: Fumio Tajima, Yutaka Matsunobu, Masashi Kitamura, Noriaki HINO, Takashi Kobayashi, Shigeru Kakugawa, Takashi Yasuhara
  • Publication number: 20070046130
    Abstract: A three-phase permanent magnet brushless motor comprises a stator having three-phase windings, and a rotor having a permanent magnet with a plurality of poles for serving as a field magnet. The stator comprises a stator core which includes a powder core that is compacted at a high density in at least teeth thereof. A combination of the number of magnetic poles of the rotor with the number of slots of the stator satisfies a condition that a least common multiple of the number of slots and the number of magnetic poles is 60 or more in a region in which the number of magnetic poles is 16 or less, and the number of slots is 12 or less. The powder core is made by compacting magnetic powders to have a green density of 7.5 g/cm3 or higher.
    Type: Application
    Filed: August 17, 2006
    Publication date: March 1, 2007
    Inventors: Yuji Enomoto, Akeshi Takahashi, Motoya Ito, Ryoso Masaki, Katsuyuki Yamazaki, Masahide Yamazaki, Masashi Kitamura, Chio Ishihara, Kazuo Asaka, Shoji Ohiwa, Yasuaki Motegi
  • Patent number: 7151335
    Abstract: A permanent magnet rotating electric machine comprises a stator having stator windings wound round a stator iron core and a permanent magnet rotor having a plurality of inserted permanent magnets in which the polarity is alternately arranged in the peripheral direction in the rotor iron core. The rotor iron core of the permanent magnets is composed of magnetic pole pieces, auxiliary magnetic poles, and a stator yoke, and furthermore has concavities formed on the air gap face of the magnetic pole pieces of the rotor iron core of the permanent magnets, gently tilting from the central part of the magnetic poles to the end thereof; resulting in a permanent magnet rotating electric machine effects of iron loss are reduced, and an electric car using highly efficient permanent magnet rotating electric machine are realized.
    Type: Grant
    Filed: February 9, 2005
    Date of Patent: December 19, 2006
    Assignee: Hitachi, Ltd.
    Inventors: Fumio Tajima, Yutaka Matsunobu, Masashi Kitamura, Noriaki Hino, Takashi Kobayashi, Shigeru Kakugawa, Takashi Yasuhara
  • Publication number: 20060279146
    Abstract: A stator of a rotating electric machine includes a stator core, and multiphase stator coils incorporated in the stator core. The stator core is formed by connecting a plurality of split core pieces. Each of the stator coils is wound around a coil bobbin installed on the outer periphery of the tooth portion of a respective one of the core pieces, by a concentrated winding method; and around mutually adjacent tooth portions, the respective coils that have the same phase and mutually different in the winding direction are continuously wound. A crossover wire for connecting the first stator coil wound around the first tooth portion and the second stator coil wound around the second tooth portion, is located at a position further toward the central side in the axial direction of the coil bobbin than the end portion of the coil bobbin, inclusive of this end portion.
    Type: Application
    Filed: May 26, 2006
    Publication date: December 14, 2006
    Applicant: Hitachi, Ltd.
    Inventors: Takashi Ishigami, Masashi Kitamura, Osamu Koizumi, Mitsuaki Mirumachi
  • Publication number: 20060181158
    Abstract: A cylindrical linear motor, an electromagnetic suspension, and a vehicle using the same, which can generate a large thrust and reduce torque pulsations and cogging torque. The cylindrical linear motor comprises a stator and a slider disposed with a gap left relative to the stator and being linearly movable relative to the stator. The stator comprises a stator core having stator salient poles, and 3-phase stator windings inserted in slots formed in the stator core. The slider comprises a plurality of permanent magnets fixed to a slider core. The motor satisfies ?p:?s=9:9±1 where ?s is a pitch of the stator salient poles and ?p is a pitch of the permanent magnets.
    Type: Application
    Filed: December 27, 2005
    Publication date: August 17, 2006
    Applicant: HITACHI, LTD.
    Inventors: Fumio Tajima, Masashi Kitamura, Houngjoong Kim, Yusuke Akami, Noriyuki Utsumi, Ken Nakamura, Kazuaki Shibahara
  • Publication number: 20060169526
    Abstract: An electric power steering system having high performance and high reliability. The electric power steering system employs, as a power supply, a wound lead storage battery in which a thin band-shaped positive plate, a thin band-shaped negative plate, and a band-shaped separator interposed between the positive and negative plates are wound to form a plate group and the plate group is immersed in an electrolyte. In a motor used for electric power steering, a plate-shaped conductor is employed as a connecting ring for electrical connection between a cable for introducing multi-phase AC power to stator coils and the stator coils.
    Type: Application
    Filed: December 14, 2005
    Publication date: August 3, 2006
    Applicant: Hitachi, Ltd.
    Inventors: Kyoko Honbo, Masanori Sakai, Toshiyuki Innami, Mitsuaki Mirumachi, Shoji Sasaki, Masashi Kitamura, Fumio Tajima, Shinji Shirakawa
  • Publication number: 20050269895
    Abstract: The stator core of a motor comprises an annular back core, and a plurality of tees created separately from the back core and secured onto the inner periphery of the back core. A stator coil is wound on each of the tees by a distributed or concentrated winding method. The stator core and stator coil are formed by molding.
    Type: Application
    Filed: May 25, 2005
    Publication date: December 8, 2005
    Applicant: Hitachi, Ltd.
    Inventors: Toshiyuki Innami, Mitsuaki Mirumachi, Osamu Koizumi, Masamichi Yagai, Masashi Kitamura, Takashi Ishigami
  • Publication number: 20050200223
    Abstract: A permanent magnet rotating electric machine comprises a stator having stator windings wound round a stator iron core and a permanent magnet rotor having a plurality of inserted permanent magnets in which the polarity is alternately arranged in the peripheral direction in the rotor iron core. The rotor iron core of the permanent magnets is composed of magnetic pole pieces, auxiliary magnetic poles, and a stator yoke, and furthermore has concavities formed on the air gap face of the magnetic pole pieces of the rotor iron core of the permanent magnets, gently tilting from the central part of the magnetic poles to the end thereof. In a permanent magnet rotating electric machine, effects of iron loss are reduced, and an electric car using highly efficient permanent magnet rotating electric machine are realized.
    Type: Application
    Filed: February 9, 2005
    Publication date: September 15, 2005
    Applicant: Hitachi, Ltd.
    Inventors: Fumio Tajima, Yutaka Matsunobu, Masashi Kitamura, Noriaki Hino, Takashi Kobayashi, Shigeru Kakugawa, Takashi Yasuhara
  • Publication number: 20050138793
    Abstract: In an abduction-type motor having a divided core 5 (a-l) formed by dividing a stator core into plural blocks and a motor stator having such a structure as the divided core may be reassembled, the motor has a coil winding frame 6 continuously formed a continuous unit of coupling parts, a part of which is flexible and made of insulation material, embedded into the individual divided cores, and a coil 7 arranged and wound by supporting the divided core so that the teeth top parts of the divided core may be directed inside and located on a circle, in which its coil winding structure has the number of coil stages at the teeth top part (external peripheral part) of the divided core larger than the number of the coil stages at the internal peripheral part, and the diameter of the teeth top part of the divided core after assembly is identical to the diameter of the teeth top part while coil winding work, and the length of the crossover line 7s between the coil windings is made enough to be equivalent to a single slot
    Type: Application
    Filed: March 1, 2005
    Publication date: June 30, 2005
    Applicants: Hitachi LTD, Japany Servo Co., LTD.
    Inventors: Yuji Enomoto, Masashi Kitamura, Miyoshi Takahashi, Makoto Ochiai, Takashi Ando, Sachio Hatori, Yasuaki Motegi, Toshimi Abukawa
  • Publication number: 20050093390
    Abstract: A rotor has magnets segmented in a circumferential direction of a periphery of a shaft, wherein magnetizing directions of the segmented magnets continuously vary, and a non-magnetic material or a ferromagnetic material is interposed in a circumferential gap between the segmented magnets. Further, a method of manufacturing a rotor comprises steps of arranging coils so that a longitudinal direction of each of the coils is along an axis of the shaft and magnetizing the segmented magnets. Still further, a rotary machine uses the rotor.
    Type: Application
    Filed: December 6, 2004
    Publication date: May 5, 2005
    Inventors: Matahiro Komuro, Masashi Kitamura, Junya Kaneda, Motoya Ito, Teruyoshi Abe, Yoshihiko Kuriyama
  • Patent number: 6876118
    Abstract: In an abduction-type motor having a divided core 5(a-l) formed by dividing a stator core into plural blocks and a motor stator having such a structure as the divided core may be reassembled, the motor has a coil winding frame 6 continuously formed a continuous unit of coupling parts, a part of which is flexible and made of insulation material, embedded into the individual divided cores, and a coil 7 arranged and wound by supporting the divided core so that the teeth top parts of the divided core may be directed inside and located on a circle, in which its coil winding structure has the number of coil stages at the teeth top part (external peripheral part) of the divided core larger than the number of the coil stages at the internal peripheral part, and the diameter of the teeth top part of the divided core after assembly is identical to the diameter of the teeth top part while coil winding work, and the length of the crossover line 7s between the coil windings is made enough to be equivalent to a single slot
    Type: Grant
    Filed: August 30, 2002
    Date of Patent: April 5, 2005
    Assignees: Hitachi, Ltd., Japan Servo Co., Ltd.
    Inventors: Yuji Enomoto, Masashi Kitamura, Miyoshi Takahashi, Makoto Ochiai, Takashi Ando, Sachio Hatori, Yasuaki Motegi, Toshimi Abukawa
  • Patent number: D541941
    Type: Grant
    Filed: January 27, 2006
    Date of Patent: May 1, 2007
    Assignee: Omron Healthcare Co., Ltd.
    Inventors: Takefumi Nakanishi, Kenji Eda, Takahide Tanaka, Yosuke Fujii, Tadashi Koike, So Noguchi, Shuji Tsuruta, Masashi Kitamura, Izumi Hachimaru