Patents by Inventor Kazuo Nishihama

Kazuo Nishihama 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: 20110234039
    Abstract: An object of the present invention is to provide a squirrel-cage induction motor with high efficiency. In a squirrel-cage induction motor including a stator in which stator windings are wound in a number of stator slots arranged at intervals in the vicinity of the inner periphery of a stator core and a rotor in which rotor conductors are embedded in a number of rotor slots arranged at intervals in the vicinity of the outer periphery of a rotor core and end rings are provided at both ends of the rotor core, the rotor core is formed of a plurality of blocks, an annular short-circuit ring is provided between respective blocks of the rotor core to short-circuit the rotor conductors, and laminated thickness of the rotor core is made larger than laminated thickness of the stator core.
    Type: Application
    Filed: February 24, 2011
    Publication date: September 29, 2011
    Inventors: Kazuo Nishihama, Hiroyuki Mikami, Tadahiro Shimozono, Keiichiro Kaihatsu, Atsushi Abe
  • Publication number: 20110210692
    Abstract: A squirrel cage induction motor includes: a stator core (11); a plurality of stator slots (12) radially disposed in a circumferential direction of the stator core (11) with predetermined intervals; a plurality of stator windings (13) housed in the stator slots respectively; a rotor core (21); a plurality of rotor slots (22) radially disposed in a circumferential direction of the rotor core (22) with predetermined intervals; a plurality of rotor conductors (23) housed in the rotor slots (22) respectively. The stator windings (13) and the rotor conductors (23) includes electrically conductive materials mainly composed of copper. An area ratio of a total area of the stator slots (12) to a total area of the rotor slots (22) is not smaller than 2.7 and not greater than 8.0 to provide compatibility between the starting characteristic (starting torque) and the steady characteristic (for a high efficiency) can be provided.
    Type: Application
    Filed: August 20, 2009
    Publication date: September 1, 2011
    Applicant: HITACHI INDUSTRIAL EQUIPMENT SYSTEMS CO., LTD.
    Inventors: Kazuo Nishihama, Hiroyuki Mikami, Tadahiro Shimozono, Keiichiro Kaihatsu
  • Patent number: 7737593
    Abstract: An electric rotation machine for windmill power generation equipped with a stator slot structure having distributed windings and a rotor pole structure having permanent magnets, wherein the number of slots per pole per phase (Nspp) is undividable by 3 times P (where P is the number of poles), and pole width rate Pw obtained by dividing pole piece width Tp by pole pitch Tr at the outermost diameters of the adjoining poles of the rotor is satisfied any of Pw?0.6, 0.67?Pw?0.71, and 0.78?Pw. The distortion factors of induced voltages in a permanent magnet type electrical rotation machine, particularly for windmill power generation, can be reduced.
    Type: Grant
    Filed: February 18, 2009
    Date of Patent: June 15, 2010
    Assignee: Hitachi, Ltd.
    Inventors: Mamoru Kimura, Kazumasa Ide, Kazuo Nishihama, Tetsuo Fujigaki, Shuji Mizutani
  • 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: 20090160284
    Abstract: An electric rotation machine for windmill power generation equipped with a stator slot structure having distributed windings and a rotor pole structure having permanent magnets, wherein the number of slots per pole per phase (Nspp) is undividable by 3 times P (where P is the number of poles), and pole width rate Pw obtained by dividing pole piece width Tp by pole pitch Tr at the outermost diameters of the adjoining poles of the rotor is satisfied any of Pw?0.6, 0.67?Pw?0.71, and 0.78?Pw. The distortion factors of induced voltages in a permanent magnet type electrical rotation machine, particularly for windmill power generation, can be reduced.
    Type: Application
    Filed: February 18, 2009
    Publication date: June 25, 2009
    Inventors: Mamoru Kimura, Kazumasa Ide, Kazuo Nishihama, Tetsuo Fujigaki, Shuji Mizutani
  • Patent number: 7541710
    Abstract: Provided is a rotating electric machine which can restrain vibration and noise induced by a radial electromagnetic force of the rotating electric machine, and in which a rotor is divided into first to fourth four rotating pieces having axial lengths of 0.29L, 0.71L, 0.71L and 0.29L where 2L is an axial length of a rotor or stator core, and secondary conductors defining effective magnetic pole opening angles, are arranged being shifted by a value which is equal to a phase difference of electric angle between axial sections of the rotor pieces in order to define skews so that phase differences of electric angles are continuous between axial sections of the first and second rotor pieces, the skews being continuous between the third and fourth rotor pieces but being not continuous between the second and third rotor pieces arranged being shifted by a value which is equal to a phase difference of electric angle between axial sections of the rotor.
    Type: Grant
    Filed: November 30, 2005
    Date of Patent: June 2, 2009
    Assignee: Hitachi, Ltd.
    Inventors: Kanako Nemoto, Yasushi Takano, Kazuhiko Takahashi, Kazuo Shima, Kazuo Nishihama
  • Patent number: 7498707
    Abstract: An electric rotation machine for windmill power generation equipped with a stator slot structure having distributed windings and a rotor pole structure having permanent magnets, wherein the number of slots per pole per phase (Nspp) is undividable by 3 times P (where P is the number of poles), and pole width rate Pw obtained by dividing pole piece width Tp by pole pitch Tr at the outermost diameters of the adjoining poles of the rotor is satisfied any of Pw?0.6, 0.67?Pw?0.71, and 0.78?Pw. The distortion factors of induced voltages in a permanent magnet type electrical rotation machine, particularly for windmill power generation, can be reduced.
    Type: Grant
    Filed: February 17, 2006
    Date of Patent: March 3, 2009
    Assignee: Hitachi, Ltd.
    Inventors: Mamoru Kimura, Kazumasa Ide, Kazuo Nishihama, Tetsuo Fujigaki, Shuji Mizutani
  • Publication number: 20080238237
    Abstract: An induction machine has a stator and rotor. The stator comprises teeth and slots and stator winding disposed in the slots. The rotor comprises a rotor core having teeth and slots and a rotor-conductor disposed in the rotor slots. Both of the stator core and rotor core are made of laminated steel sheets, and the teeth and slots made of steel sheets are formed by etching.
    Type: Application
    Filed: February 6, 2008
    Publication date: October 2, 2008
    Inventors: Kazuo Nishihama, Teruyoshi Abe, Yoshihisa Ishikawa, Hiroyuki Mikami
  • Publication number: 20080238235
    Abstract: A self-starting permanent magnet synchronous motor which demonstrates satisfactory acceleration performance even at a reduced supply voltage or with an increased load torque, and a compressor using the same. The motor comprises a stator having a stator winding and a rotor having a cage winding and a permanent magnet on the rotor core. The torque component generated by the cage winding is maximal at 1 in the slip range of 0 to 1.
    Type: Application
    Filed: January 25, 2008
    Publication date: October 2, 2008
    Inventors: Akeshi TAKAHASHI, Satoshi Kikuchi, Hiroyuki Mikami, Kazuo Nishihama, Tomio Yoshikawa, Baiying Huang
  • Patent number: 7129613
    Abstract: A rotor conductor upper portion positioned near to an outer periphery of a rotor has a trapezoidal, cross sectional shape, a rotor conductor lower portion positioned nearer to a center of the rotor than the rotor conductor upper portion has a rectangular, cross sectional shape, and the rotor conductor upper portion has a height h1=27 mm or more in the case where rotor conductors are made of brass, and a height h1=7 mm or more in the case where the rotor conductors are made of copper.
    Type: Grant
    Filed: March 9, 2005
    Date of Patent: October 31, 2006
    Assignee: Hitachi, Ltd.
    Inventors: Kazuo Nishihama, Kazumasa Ide, Tetsuo Fujigaki, Shuuji Mizutani, Takeshi Nakayama
  • Publication number: 20060202581
    Abstract: An electric rotation machine for windmill power generation equipped with a stator slot structure having distributed windings and a rotor pole structure having permanent magnets, wherein the number of slots per pole per phase (Nspp) is undividable by 3 times P (where P is the number of poles), and pole width rate Pw obtained by dividing pole piece width Tp by pole pitch Tr at the outermost diameters of the adjoining poles of the rotor is satisfied any of Pw?0.6, 0.67?Pw?0.71, and 0.78?Pw. The distortion factors of induced voltages in a permanent magnet type electrical rotation machine, particularly for windmill power generation, can be reduced.
    Type: Application
    Filed: February 17, 2006
    Publication date: September 14, 2006
    Inventors: Mamoru Kimura, Kazumasa Ide, Kazuo Nishihama, Tetsuo Fujigaki, Shuji Mizutani
  • Publication number: 20060163969
    Abstract: Provided is a rotating electric machine which can restrain vibration and noise induced by a radial electromagnetic force of the rotating electric machine, and in which a rotor is divided into first to fourth four rotating pieces having axial lengths of 0.29 L, 0.71 L, 0.71 L and 0.29 L where 2 L is an axial length of a rotor or stator core, and secondary conductors defining effective magnetic pole opening angles, are arranged being shifted by a value which is equal to a phase difference of electric angle between axial sections of the rotator pieces in order to define skews so that phase differences of electric angles are continuous between axial sections of the first and second rotor pieces, the skews being continuous between the third and fourth rotor pieces but being not continuous between the second and third rotor piece.
    Type: Application
    Filed: November 30, 2005
    Publication date: July 27, 2006
    Applicant: Hitachi, LTD.
    Inventors: Kanako Nemoto, Yasushi Takano, Kazuhiko Takahashi, Kazuo Shima, Kazuo Nishihama
  • Publication number: 20050156476
    Abstract: A rotor conductor upper portion positioned near to an outer periphery of a rotor has a trapezoidal, cross sectional shape, a rotor conductor lower portion positioned nearer to a center of the rotor than the rotor conductor upper portion has a rectangular, cross sectional shape, and the rotor conductor upper portion has a height h1=27 mm or more in the case where rotor conductors are made of brass, and a height h1=7 mm or more in the case where the rotor conductors are made of copper.
    Type: Application
    Filed: March 9, 2005
    Publication date: July 21, 2005
    Inventors: Kazuo Nishihama, Kazumasa Ide, Tetsuo Fujigaki, Shuuji Mizutani, Takeshi Nakayama
  • Patent number: 6882078
    Abstract: A rotor conductor upper portion positioned near to an outer periphery of a rotor has a trapezoidal, cross sectional shape, a rotor conductor lower portion positioned nearer to a center of the rotor than the rotor conductor upper portion has a rectangular, cross sectional shape, and the rotor conductor upper portion has a height h1=27 mm or more in the case where rotor conductors are made of brass, and a height h1=7 mm or more in the case where the rotor conductors are made of copper.
    Type: Grant
    Filed: February 11, 2004
    Date of Patent: April 19, 2005
    Assignee: Hitachi, Ltd.
    Inventors: Kazuo Nishihama, Kazumasa Ide, Tetsuo Fujigaki, Shuuji Mizutani, Takeshi Nakayama
  • Publication number: 20040183390
    Abstract: A rotor conductor upper portion positioned near to an outer periphery of a rotor has a trapezoidal, cross sectional shape, a rotor conductor lower portion positioned nearer to a center of the rotor than the rotor conductor upper portion has a rectangular, cross sectional shape, and the rotor conductor upper portion has a height h1=27 mm or more in the case where rotor conductors are made of brass, and a height h1=7 mm or more in the case where the rotor conductors are made of copper.
    Type: Application
    Filed: February 11, 2004
    Publication date: September 23, 2004
    Inventors: Kazuo Nishihama, Kazumasa Ide, Tetsuo Fujigaki, Shuuji Mizutani, Takeshi Nakayama
  • Publication number: 20040119347
    Abstract: In order to provide a rotating electric machine which reduces vibration, noise and temperature rise and eases assembling work thereof through an improvement of a frame structure and a securing method between a stator iron core and the frame. In a rotating electric machine comprising a stator iron core 6 having a stator winding, a frame 1 having intermediate plates 2 for securing the stator iron core 6 to the frame 1, a rotor iron core 5 having a rotor winding, the intermediate plates (brackets) 2 which rotatably support the rotor at both sides in the frame axial direction under the condition of accommodating the stator iron core 6 and the rotor iron core 5 in the frame 1, cooling fans 4 for ventilation through rotation together with a rotor shaft 3, and a shaft portion extending from the brackets for directly coupling to a load, wherein, the securing between the frame 1 and the stator iron core 6 is performed by a welding structure at a welding portion 9.
    Type: Application
    Filed: December 11, 2003
    Publication date: June 24, 2004
    Applicants: Hitachi, Ltd., Hitachi Car Engineering Co., Ltd.
    Inventors: Tetsuo Fujigaki, Hidekazu Midorikawa, Shuji Mizutani, Kazuo Nishihama, Shuichi Ishizawa, Katsuji Takei, Satoru Takaboshi, Shirou Kikuchi, Isoo Sugano, Masanori Matsumoto, Kenji Takahashi, Shinichi Ozawa
  • Publication number: 20030173837
    Abstract: In order to provide a rotating electric machine which reduces vibration, noise and temperature rise and eases assembling work thereof through an improvement of a frame structure and a securing method between a stator iron core and the frame. In a rotating electric machine comprising a stator iron core 6 having a stator winding, a frame 1 having intermediate plates 2 for securing the stator iron core 6 to the frame 1, a rotor iron core 5 having a rotor winding, the intermediate plates (brackets) 2 which rotatably support the rotor at both sides in the frame axial direction under the condition of accommodating the stator iron core 6 and the rotor iron core 5 in the frame 1, cooling fans 4 for ventilation through rotation together with a rotor shaft 3, and a shaft portion extending from the brackets for directly coupling to a load, wherein, the securing between the frame 1 and the stator iron core 6 is performed by a welding structure at a welding portion 9.
    Type: Application
    Filed: December 19, 2002
    Publication date: September 18, 2003
    Inventors: Tetsuo Fujigaki, Hidekazu Midorikawa, Shuji Mizutani, Kazuo Nishihama, Shuichi Ishizawa, Katsuji Takei, Satoru Takaboshi, Shirou Kikuchi, Isoo Sugano, Masanori Matsumoto, Kenji Takahashi, Shinichi Ozawa