Patents by Inventor Yasuomi Yagi

Yasuomi Yagi 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: 7294943
    Abstract: An electric rotating machine capable of lowering the temperature of a rotor disposed, wherein at least one of closed ventilation loops for cooling is formed, one of the loops constituting a ventilation passage communicating with an exhaust side through a heat source of the end of the generator to a cooler, thereby to supply cooling wind to the rotor after it passes through the cooler.
    Type: Grant
    Filed: November 3, 2005
    Date of Patent: November 13, 2007
    Assignee: Hitachi, Ltd.
    Inventors: Kenichi Hattori, Kazumasa Ide, Akiyoshi Komura, Takashi Watanabe, Ryoichi Shiobara, Yasuomi Yagi, Kengo Iwashige, Keiji Kobashi
  • Patent number: 7071586
    Abstract: An electric rotating machine capable of lowering the temperature of a rotor disposed, wherein at least one of closed ventilation loops for cooling is formed, one of the loops constituting a ventilation passage communicating with an exhaust side through a heat source of the end of the generator to a cooler, thereby to supply cooling wind to the rotor after it passes through the cooler.
    Type: Grant
    Filed: March 4, 2002
    Date of Patent: July 4, 2006
    Assignee: Hitachi, Ltd.
    Inventors: Kenichi Hattori, Kazumasa Ide, Akiyoshi Komura, Takashi Watanabe, Ryoichi Shiobara, Yasuomi Yagi, Kengo Iwashige, Keiji Kobashi
  • Publication number: 20060055255
    Abstract: An electric rotating machine capable of lowering the temperature of a rotor disposed, wherein at least one of closed ventilation loops for cooling is formed, one of the loops constituting a ventilation passage communicating with an exhaust side through a heat source of the end of the generator to a cooler, thereby to supply cooling wind to the rotor after it passes through the cooler.
    Type: Application
    Filed: November 3, 2005
    Publication date: March 16, 2006
    Applicant: Hitachi, Ltd.
    Inventors: Kenichi Hattori, Kazumasa Ide, Akiyoshi Komura, Takashi Watanabe, Ryoichi Shiobara, Yasuomi Yagi, Kengo Iwashige, Keiji Kobashi
  • Publication number: 20040090131
    Abstract: An electric rotating machine capable of lowering the temperature of a rotor disposed, wherein at least one of closed ventilation loops for cooling is formed, one of the loops constituting a ventilation passage communicating with an exhaust side through a heat source of the end of the generator to a cooler, thereby to supply cooling wind to the rotor after it passes through the cooler.
    Type: Application
    Filed: September 4, 2003
    Publication date: May 13, 2004
    Inventors: Kenichi Hattori, Kazumasa Ide, Akiyoshi Komura, Takashi Watanabe, Ryoichi Shiobara, Yasuomi Yagi, Kengo Iwashige, Keiji Kobashi
  • Patent number: 6538351
    Abstract: A rotating machine having a stator core and coolers for cooling a cooling medium which is circulated inside the machine by the rotation of a fan installed near a rotating axis of the rotating machine. The coolers being installed in a ventilation passage for the cooling medium and including at least one cooler installed in one ventilation passage extending from an exhaust side of the fan to a suction side of the fan via the stator core, and at least another cooler installed in another ventilation passage extending from the exhaust side of the fan in the one ventilation passage to an inside of an inner surface of the stator core.
    Type: Grant
    Filed: March 18, 2002
    Date of Patent: March 25, 2003
    Assignee: Hitachi, Ltd.
    Inventors: Akitomi Semba, Tadashi Sonobe, Takashi Watanabe, Yasuomi Yagi, Junji Sato, Shinsaku Hakuta, Hideaki Mori, Eiji Tsuji, Kenichi Hattori, Atsushi Ishihara
  • Publication number: 20020101121
    Abstract: A rotating machine having a stator core and coolers for cooling a cooling medium which is circulated inside the machine by the rotation of a fan installed near a rotating axis of the rotating machine. The coolers being installed in a ventilation passage for the cooling medium and including at least one cooler installed in one ventilation passage extending from an exhaust side of the fan to a suction side of the fan via the stator core, and at least another cooler installed in another ventilation passage extending from the exhaust side of the fan in the one ventilation passage to an inside of an inner surface of the stator core.
    Type: Application
    Filed: March 18, 2002
    Publication date: August 1, 2002
    Inventors: Akitomi Semba, Tadashi Sonobe, Takashi Watanabe, Yasuomi Yagi, Junji Sato, Shinsaku Hakuta, Hideaki Mori, Eiji Tsuji, Kenichi Hattori, Atsushi Ishihara
  • Patent number: 6426578
    Abstract: An electric rotating machine having a rotor, rotatably disposed in an inner radius side of a stator through a gap, including rotor windings contained in a plurality of slots formed in a rotor core, a slot insulation placed between the rotor winding and the slot, an insulation block placed between a wedge arranged at a peripheral side of the rotor core outward of the rotor winding of the slot and the rotor winding. At least one of the slot insulation and the insulation block is an insulation formed by filling or mixing granular and/or short-fiber insulating materials having a thermal conductivity higher than 5 W/m·K in a resin and a thermal conductivity in a thickness direction higher than 0.35 W/m·K.
    Type: Grant
    Filed: May 9, 2001
    Date of Patent: July 30, 2002
    Assignee: Hitachi, Ltd.
    Inventors: Hideaki Mori, Shigeo Amagi, Saburo Usami, Tadashi Sonobe, Yasuomi Yagi, Tomoya Tsunoda, Mitsuru Onoda
  • Publication number: 20020070621
    Abstract: An electric rotating machine having a rotor, rotatably disposed in an inner radius side of a stator through a gap, including rotor windings contained in a plurality of slots formed in a rotor core, a slot insulation placed between the rotor winding and the slot, an insulation block placed between a wedge arranged at a peripheral side of the rotor core outward of the rotor winding of the slot and a retaining insulation placed between a retainer for fixing the rotor winding in both sides in a shaft direction of the rotor core and the rotor winding. At least one of the slot insulation, the insulation block and the retaining insulation is an insulation formed by filling or mixing granular and/or short-fiber insulating materials having a thermal conductivity higher than 5 W/m·K in a resin and a thermal conductivity in a thickness direction higher than 0.35 W/m·K.
    Type: Application
    Filed: May 9, 2001
    Publication date: June 13, 2002
    Inventors: Hideaki Mori, Shigeo Amagi, Saburo Usami, Tadashi Sonobe, Yasuomi Yagi, Tomoya Tsunoda, Mitsuru Onoda
  • Patent number: 6359351
    Abstract: A rotating machine having a stator core and being equipped with coolers for cooling a cooling medium which is circulated inside the machine by the rotation of a fan installed near a rotating axis of the rotating machine. The coolers are installed in a ventilation passage for the cooling medium and include a primary cooler installed in a primary ventilation passage extending from an exhaust side of the fan to a suction side of the fan via the stator core, and a secondary cooler installed in a secondary ventilation passage extending from the exhaust side of the fan in the primary ventilation passage to an inside of an inner surface of the stator core via the stator core.
    Type: Grant
    Filed: June 4, 2001
    Date of Patent: March 19, 2002
    Assignee: Hitachi, Ltd.
    Inventors: Akitomi Semba, Tadashi Sonobe, Takashi Watanabe, Yasuomi Yagi, Junji Sato, Shinsaku Hakuta, Hideaki Mori, Eiji Tsuji, Kenichi Hattori, Atsushi Ishihara
  • Patent number: 6265795
    Abstract: A rotating machine having a core and being equipped with coolers for cooling a cooling medium which is circulated inside the machine by the rotation of a fan installed near the rotating axis. The coolers are installed in a ventilation passage for the cooling medium and comprise a primary cooler installed in a primary ventilation passage extending from the exhaust side of a fan installed near the rotating axis to the suction side of said fan via the core, and a secondary cooler installed in a secondary passage that is branched from the primary ventilation passage.
    Type: Grant
    Filed: June 5, 2000
    Date of Patent: July 24, 2001
    Assignee: Hitachi, LTD
    Inventors: Akitomi Semba, Tadashi Sonobe, Takashi Watanabe, Yasuomi Yagi, Junji Sato, Shinsaku Hakuta, Hideaki Mori, Eiji Tsuji, Kenichi Hattori, Atsushi Ishihara
  • Patent number: 6262502
    Abstract: A rotating machine having a stator core and being equipped with coolers for cooling a cooling medium which is circulated inside the machine by the rotation of a fan installed near the rotating axis. The coolers are installed in a ventilation passage for the cooling medium and comprise a primary cooler installed in a primary ventilation passage extending from the exhaust side of a fan installed near the rotating axis to the suction side of the fan via the stator core, and a secondary cooler installed in a secondary ventilation passage extending from the exhaust side of the fan in the primary ventilation passage to the inside of the inner surface of the stator core via the stator core.
    Type: Grant
    Filed: June 5, 2000
    Date of Patent: July 17, 2001
    Assignee: Hitachi, LTD
    Inventors: Akitomi Semba, Tadashi Sonobe, Takashi Watanabe, Yasuomi Yagi, Junji Sato, Shinsaku Hakuta, Hideaki Mori, Eiji Tsuji, Kenichi Hattori, Atsushi Ishihara
  • Patent number: 6242825
    Abstract: An the electric rotating machine which is compact and of reduced cost by improving the thermal conductivity of the main insulation in the thickness direction while maintaining the insulation breakdown voltage of the main insulation high. The initial breakdown voltage V in the thickness direction of the main insulator 30 of the stator winding 3 is higher than 20 kV/mm, and the thermal conductivity &lgr; in the thickness direction is within a range of 0.35 to 1 W/m·K, and the product V&lgr; of the initial breakdown voltage V and the thermal conductivity &lgr; satisfies a relationship of 7≦V&lgr;≦20 (MWA/m2·K). The amount of resin is within a range of 20 to 50 weight % of the main insulation material.
    Type: Grant
    Filed: November 18, 1999
    Date of Patent: June 5, 2001
    Assignee: Hitachi, Ltd.
    Inventors: Hideaki Mori, Shigeo Amagi, Saburo Usami, Tadashi Sonobe, Yasuomi Yagi, Tomoya Tsunoda, Mitsuru Onoda
  • Patent number: 6201323
    Abstract: In order to provide a rotating machine in which the temperature increase distribution inside the machine can be equalized, not only is a primary cooler installed in the primary ventilation passage that extends from the exhaust side of the fans and installed on the rotating axis to the suction side of the fans and via the core, but a secondary cooler is installed in the secondary ventilation passage that is branched from the primary ventilation passage, thus making it possible to further cool part of the cooling medium, which has once been cooled by the primary cooler, by means of the secondary cooler, that is, to cool the cooling medium by circulating it through the coolers twice.
    Type: Grant
    Filed: November 18, 1999
    Date of Patent: March 13, 2001
    Assignee: Hitachi, Ltd.
    Inventors: Akitomi Semba, Tadashi Sonobe, Takashi Watanabe, Yasuomi Yagi, Junji Sato, Shinsaku Hakuta, Hideaki Mori, Eiji Tsuji, Kenichi Hattori, Atsushi Ishihara
  • Patent number: 5469009
    Abstract: The rotor 2 of a rotating field type turbine generator is provided with slots 3 for accommodating the field windings, wedges 4 positioned at the portions of the magnetic poles on the rotor 2 for holding the field windings and wedges 5 positioned between the magnetic poles on the rotor. These wedges 4 and 5 are constituted by metal bars without joints to enhance damper effect thereby. Magnetomotive forces due to higher harmonics, which causes temperature rise of the rotor 2 and torque ripple during starting with thyristors, induces an elliptic rotating magnetic field having the longer diameter on d axis extending in the direction of magnetomotive force induced by the field windings and the shorter diameter on q axis perpendicular to d axis, and thus a larger eddy current is induced flowing along q axis on the rotor 2 than that flowing along d axis.
    Type: Grant
    Filed: June 15, 1994
    Date of Patent: November 21, 1995
    Assignee: Hitachi, Ltd.
    Inventors: Shinichi Wakui, Kazumasa Ide, Haruo Koharagi, Miyoshi Takahashi, Kado Miyakawa, Yasuomi Yagi
  • Patent number: 5459363
    Abstract: The rotor for a dynamo electric machine serving as a synchronous generator as well as being designed operable as a variable speed motor for starting a prime mover for the synchronous generator, the rotor (1) comprising a rotor core (2), a plurality of slots (4) disposed around the circumference of the rotor core (2) and extending along the axial direction of the rotor core (2), rotor windings (3) being accommodated in the slots (4) and wedges (6) being accommodated in the slots (4) over the rotor windings (3) near at the surface of the rotor core (2) for preventing the rotor windings (3) from being pushed out due to a centrifugal force caused by rotation of the rotor (1), wherein wedges (6) where an eddy current flows are formed by Cu-0.05.about.4 wt % Zr-0.3.about.5 wt % Ni-0.2.about.1.5 wt % Si having a 0.2% proof stress equal to or more than about 20 Kg/mm.sup.
    Type: Grant
    Filed: October 20, 1994
    Date of Patent: October 17, 1995
    Assignee: Hitachi, Ltd.
    Inventors: Kado Miyakawa, Takanobu Mori, Yasuomi Yagi, Fumio Shibata
  • Patent number: 4862749
    Abstract: A shaft torsional vibration monitor for a poly phase turbine generator and its prime mover turbine connected thereto comprises an electrical torque detector detecting electromagnetic torque applied to the turbine generator rotor, a memory unit capable of storing plurality sets of torque variation data due to system disturbances each having an initial torque variation rate more than a predetermined amount, a first processor fetching the sets of torque variation data one by one from the memory unit and determining the corresponding shaft torsional vibration and a second processor determining fatigue and life expectancy of the rotary shaft system for the turbine generator and its turbine by accumulating torsional stresses caused by respective shaft torsional vibrations.
    Type: Grant
    Filed: March 28, 1988
    Date of Patent: September 5, 1989
    Assignee: Hitachi, Ltd.
    Inventor: Yasuomi Yagi
  • Patent number: 4625520
    Abstract: A superconducting device including a superconducting coil is suitable for use in a nuclear magnetic resonance computer tomography apparatus which requires a highly-uniform, highly-stable magnetostatic field. However, a serious problem arises when a large-sized superconducting coil is to be installed in a small room of a hospital or the like. A superconducting device capable of solving this problem is disclosed in which a very low temperature vessel having the form of a cylinder contains a superconducting coil in a state that the superconducting coil is immersed in a very low temperature coolant, and very low temperature coolant inlet port communicating the very low temperature vessel for introducing the very low temperature coolant into the very low temperature vessel is provided along a radial direction perpendicular to the horizontal center axis of the superconducting device and inclined at a desired angle with a vertical direction.
    Type: Grant
    Filed: August 29, 1985
    Date of Patent: December 2, 1986
    Assignee: Hitachi, Ltd.
    Inventors: Yasuomi Yagi, Ken Takahashi, Takeo Nemoto
  • Patent number: 4502296
    Abstract: A cryostat including a horizontal hollow space section of room temperature in which a liquid helium vessel is supported by a plurality of support structures each having a multiple cylinder of small thickness and a liquid nitrogen vessel is supported by a plurality of tension rods.
    Type: Grant
    Filed: March 26, 1984
    Date of Patent: March 5, 1985
    Assignee: Hitachi, Ltd.
    Inventors: Hisanao Ogata, Takeo Nemoto, Yoshinori Hakuraku, Yasuomi Yagi