Patents by Inventor Osamu Koizumi

Osamu Koizumi 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: 20080284269
    Abstract: A magnetic gap is provided between a permanent magnet of a rotor and an auxiliary magnet pole portion which is arranged adjacent to the permanent magnet in a peripheral direction. A gradual change in a magnetic flux density distribution of a surface of the rotor is obtained and a cogging torque and a torque pulsation are restrained. By obtaining a reluctance torque according to the auxiliary magnetic pole, a permanent magnet electric rotating machine in which the cogging torque and the torque pulsation are restrained can be obtained and further an electromotive vehicle having the permanent magnet electric rotating machine can be provided.
    Type: Application
    Filed: July 18, 2008
    Publication date: November 20, 2008
    Applicants: Hitachi, Ltd., Hitachi Car Engineering Co., Ltd.
    Inventors: Fumio Tajima, Yutaka Matsunobu, Shouichi Kawamata, Suetaro Shibukawa, Osamu Koizumi, Keiji Oda
  • Patent number: 7453179
    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 31, 2007
    Date of Patent: November 18, 2008
    Assignee: Hitachi, Ltd.
    Inventors: Toshiyuki Innami, Mitsuaki Mirumachi, Osamu Koizumi, Masamichi Yagai, Masashi Kitamura, Takashi Ishigami
  • Patent number: 7446448
    Abstract: A magnetic gap is provided between a permanent magnet of a rotor and an auxiliary magnet pole portion which is arranged adjacent to the permanent magnet in a peripheral direction. A gradual change in a magnetic flux density distribution of a surface of the rotor is obtained and a cogging torque and a torque pulsation are restrained. By obtaining a reluctance torque according to the auxiliary magnetic pole, a permanent magnet electric rotating machine in which the cogging torque and the torque pulsation are restrained can be obtained and further an electromotive vehicle having the permanent magnet electric rotating machine can be provided.
    Type: Grant
    Filed: August 25, 2006
    Date of Patent: November 4, 2008
    Assignees: Hitachi, Ltd., Hitachi Car Engineering Co., Ltd.
    Inventors: Fumio Tajima, Yutaka Matsunobu, Shouichi Kawamata, Suetaro Shibukawa, Osamu Koizumi, Keiji Oda
  • Patent number: 7417349
    Abstract: A rotating electric machine comprises a stator having stator salient poles, three-phases windings wound around said stator salient poles, a rotor rotatable held inside the said stator, and permanent magnets inserted into said rotor and positioned opposite to said stator salient poles. The three-phase windings are concentratively wound around each of the stator salient poles, with windings of each phase wound around at more than one stator salient pole. The windings of each phase have a phase difference of voltage between at least one of the windings and the other.
    Type: Grant
    Filed: September 26, 2005
    Date of Patent: August 26, 2008
    Assignees: Hitachi, Ltd., Hitachi Car Engineering Co., Ltd.
    Inventors: Fumio Tajima, Yutaka Matsunobe, Shouichi Kawamata, Suetaro Shibukawa, Osamu Koizumi, Keijiro Oda
  • Patent number: 7378773
    Abstract: A magnetic gap is provided between a permanent magnet of a rotor and an auxiliary magnet pole portion which is arranged adjacent to the permanent magnet in a peripheral direction. A gradual change in a magnetic flux density distribution of a surface of the rotor is obtained and a cogging torque and a torque pulsation are restrained. By obtaining a reluctance torque according to the auxiliary magnetic pole, a permanent magnet electric rotating machine in which the cogging torque and the torque pulsation are restrained can be obtained and further an electromotive vehicle having the permanent magnet electric rotating machine can be provided.
    Type: Grant
    Filed: August 25, 2006
    Date of Patent: May 27, 2008
    Assignees: Hitachi, Ltd., Hitachi Car Engineering Co., Ltd.
    Inventors: Fumio Tajima, Yutaka Matsunobu, Shouichi Kawamata, Suetaro Shibukawa, Osamu Koizumi, Keiji Oda
  • Patent number: 7294988
    Abstract: A rotary sensor that outputs two analog signals, such as one sine wave and one cosine wave and has multiple periods within one period of the electrical angle of a motor is employed. The motor is energized at each position for a specified length of time upon its startup by using multiple electrical angles corresponding to the multiple candidate absolute angles obtained from the rotary sensor signal as the initial position of the motor, and the electrical angle at which the motor acceleration becomes maximum is determined as the absolute angle. While the motor drive is in operation, on the other hand, the phase difference ?? between the phase of the motor at the counter electromotive voltage and the control phase is directly computed from the parameters of the motor, sensed current, voltage command and angle speed so as to correct the shifted position.
    Type: Grant
    Filed: December 6, 2005
    Date of Patent: November 13, 2007
    Assignee: Hitachi, Ltd.
    Inventors: Toshiyuki Ajima, Hideki Miyazaki, Yukio Kawabata, Kiyoshi Sakamoto, Takao Yanai, Osamu Koizumi
  • 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
  • Patent number: 7215055
    Abstract: A rotating electric machine comprises a stator having stator salient poles, three-phase windings wound around said stator salient poles, a rotor rotatable held inside the said stator, and permanent magnets inserted into said rotor and positioned opposite to said stator salient poles. The three-phase windings are concentratively wound around each of the stator salient poles, with windings of each phase wound around more than one stator salient pole. The windings of each phase have a phase difference of voltage between at least one of the windings and the other.
    Type: Grant
    Filed: September 26, 2005
    Date of Patent: May 8, 2007
    Assignees: Hitachi, Ltd., Hitachi Car Engineering Co., Ltd.
    Inventors: Fumio Tajima, Yutaka Matsunobe, Shouichi Kawamata, Suetaro Shibukawa, Osamu Koizumi, Keijiro Oda
  • Publication number: 20070084652
    Abstract: A hybrid electric vehicle employs a permanent magnet type dynamo-electric machine having a stator with a stator iron core around which a stator coil is wound, and a rotor arranged in the stator at a rotational gap and having a plurality of permanent magnets arranged and fixed within a rotor iron core in a peripheral direction. A ratio exists between a maximum torque output by the dynamo-electric machine when the dynamo-electric machine normally rotates and a torque output by the dynamo-electric machine when reverse rotating establishes in a relation 1:1.05-1.2, whereby torque at the reverse rotation becomes greater.
    Type: Application
    Filed: December 14, 2006
    Publication date: April 19, 2007
    Applicant: HITACHI, LTD.
    Inventors: Yutaka Matsunobu, Fumio Tajima, Shouichi Kawamata, Osamu Koizumi, Sanshiro Obara
  • Patent number: 7196447
    Abstract: A rotating electric machine comprises a stator having stator salient poles, three-phases windings wound around the stator salient poles, a rotor rotatable held inside the stator, and permanent magnets inserted into the rotor and positioned opposite to the stator salient poles. Three-phase windings, which are concentratively wound around each of the stator salient poles, are wound around more than one stator salient pole. The windings of each phase have a phase difference of voltage between at least one of the windings and the other.
    Type: Grant
    Filed: September 26, 2005
    Date of Patent: March 27, 2007
    Assignees: Hitachi, Ltd., Hitachi Car Engineering Co., Ltd.
    Inventors: Fumio Tajima, Yutaka Matsunobe, Shouichi Kawamata, Suetaro Shibukawa, Osamu Koizumi, Keijiro Oda
  • Publication number: 20070045037
    Abstract: The present invention provides an electric power steering apparatus, in which reduction and thickness thereof can be achieved, radiation performance thereof can concurrently be ensured, and manufacturing and running costs thereof can also be reduced, even when the apparatus includes a structure having a motor and a motor control device integrated therewith. The apparatus includes a motor which assists in steering operations, a motor control device which controls the motor, and a housing which accommodates the motor and the motor control device. The housing includes a motor accommodation portion which accommodates the motor, and a control device accommodation portion which accommodates the motor control device. The motor control device includes a drive unit which drives the motor, and a control unit which controls the motor. The drive unit is disposed in a position in the control device accommodation portion, the position being in proximity to the motor accommodation portion.
    Type: Application
    Filed: July 18, 2006
    Publication date: March 1, 2007
    Applicant: Hitachi, Ltd.
    Inventors: Hideto Yoshinari, Masahide Harada, Kaoru Uchiyama, Osamu Koizumi
  • Publication number: 20060284508
    Abstract: A magnetic gap is provided between a permanent magnet of a rotor and an auxiliary magnet pole portion which is arranged adjacent to the permanent magnet in a peripheral direction. A gradual change in a magnetic flux density distribution of a surface of the rotor is obtained and a cogging torque and a torque pulsation are restrained. By obtaining a reluctance torque according to the auxiliary magnetic pole, a permanent magnet electric rotating machine in which the cogging torque and the torque pulsation are restrained can be obtained and further an electromotive vehicle having the permanent magnet electric rotating machine can be provided.
    Type: Application
    Filed: August 25, 2006
    Publication date: December 21, 2006
    Applicants: Hitachi, Ltd., Hitachi Car Engineering Co., Ltd.
    Inventors: Fumio Tajima, Yutaka Matsunobu, Shouichi Kawamata, Suetaro Shibukawa, Osamu Koizumi, Keiji Oda
  • Publication number: 20060279154
    Abstract: A magnetic gap is provided between a permanent magnet of a rotor and an auxiliary magnet pole portion which is arranged adjacent to the permanent magnet in a peripheral direction. A gradual change in a magnetic flux density distribution of a surface of the rotor is obtained and a cogging torque and a torque pulsation are restrained. By obtaining a reluctance torque according to the auxiliary magnetic pole, a permanent magnet electric rotating machine in which the cogging torque and the torque pulsation are restrained can be obtained and further an electromotive vehicle having the permanent magnet electric rotating machine can be provided.
    Type: Application
    Filed: August 25, 2006
    Publication date: December 14, 2006
    Applicants: Hitachi, Ltd., Hitachi Car Engineering Co., Ltd.
    Inventors: Fumio Tajima, Yutaka Matsunobu, Shouichi Kawamata, Suetaro Shibukawa, Osamu Koizumi, Keiji Oda
  • 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
  • Patent number: 7147929
    Abstract: A highly reliable resin-molded stator not suffering insulation breakdown between the different phases of the stator coils even when the operation mode where the output of a rotary machine using a resin-molded stator in which a stator coil wound around a plurality of slots and a stator coil provided at the stator core end are resin-molded is to be increased from the level under a stopped status to the maximum achievable level within a short time is repeated. Also disclosed is a method of manufacturing such a stator, and a rotary machine using the same.
    Type: Grant
    Filed: September 2, 2005
    Date of Patent: December 12, 2006
    Assignee: Hitachi, Ltd.
    Inventors: Shigeo Amagi, Osamu Koizumi
  • Publication number: 20060272870
    Abstract: The invention provides a hybrid electric vehicle employing a permanent magnet type dynamo-electric machine structured such that a torque at a time of reverse rotation is greater than a maximum torque output by a dynamo-electric machine when the dynamo-electric machine normally rotates. Further, the present invention provides a hybrid electric vehicle in which a dynamo-electric machine and an engine are connected to a drive shaft in series and no gear for switching between forward and backward movements is provided, wherein there is employed a permanent magnet type dynamo-electric machine structured such that a torque output by the dynamo-electric machine when the hybrid electric vehicle moves backward (the dynamo-electric machine reverse rotates) is greater than a maximum torque output by the dynamo-electric machine when the hybrid electric vehicle moves forward (the dynamo-electric machine normally rotates).
    Type: Application
    Filed: August 15, 2006
    Publication date: December 7, 2006
    Applicant: HITACHI, LTD.
    Inventors: Yutaka Matsunobu, Fumio Tajima, Shouichi Kawamata, Osamu Koizumi, Sanshiro Obara
  • Patent number: 7122934
    Abstract: A rotating electric machine comprises: a stator including a stator iron core having a plurality of slots and a stator winding incorporated in the plurality of slots; and a rotor rotatably disposed in the stator via a clearance; wherein a mold (i.e., a slot insulator) made of an insulating resin is brought into close contact with the surface of a projection (i.e., a tooth core) of the stator iron core, formed between the adjacent slots, the thickness of the mold at a portion of the projection wound with the stator winding being smaller than that of the mold at other portions. Thus, it is possible to provide the rotating electric machine in which thermal resistance generated between the stator winding and the stator iron core can be reduced, thermal transmittance of heat generated in the stator winding to the stator iron core can be enhanced, and the cooling efficiency of the stator winding can be enhanced.
    Type: Grant
    Filed: October 13, 2004
    Date of Patent: October 17, 2006
    Assignee: Hitachi, Ltd.
    Inventors: Noriaki Yamamoto, Fumio Tajima, Osamu Koizumi
  • Patent number: 7119470
    Abstract: A magnetic gap is provided between a permanent magnet of a rotor and an auxiliary magnet pole portion which is arranged adjacent to the permanent magnet in a peripheral direction. A gradual change in a magnetic flux density distribution of a surface of the rotor is obtained and a cogging torque and a torque pulsation are restrained. By obtaining a reluctance torque according to the auxiliary magnetic pole, a permanent magnet electric rotating machine in which the cogging torque and the torque pulsation are restrained can be obtained and further an electromotive vehicle having the permanent magnet electric rotating machine can be provided.
    Type: Grant
    Filed: March 17, 2005
    Date of Patent: October 10, 2006
    Assignees: Hitachi, Ltd., Hitachi Car Engineering Co., Ltd.
    Inventors: Fumio Tajima, Yutaka Matsunobu, Shouichi Kawamata, Suetaro Shibukawa, Osamu Koizumi, Keiji Oda
  • Patent number: 7067943
    Abstract: A highly reliable resin-molded stator not suffering insulation breakdown between different phases of stator coils even when the operation mode is repeated where the output of a rotary machine using a resin-molded stator is to be increased from the level under a stopped status to the maximum achievable level within a short time. Also provided are methods of manufacturing such a stator, and a rotary machine using the same. The a resin-molded stator of the invention comprises a stator core, electrically insulated stator coils wound around the plurality of slots or protrusions provided in the axial direction of the stator core, and molding resin with which are molded the stator core and the stator coils located at the aforementioned slots or protrusions. At the stator core end, non-adhesive structure is established between the molding resin and at least one of the end faces of the stator core.
    Type: Grant
    Filed: March 19, 2003
    Date of Patent: June 27, 2006
    Assignee: Hitachi, Ltd.
    Inventors: Shigeo Amagi, Osamu Koizumi