Patents by Inventor Syuuji Saitou

Syuuji Saitou 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: 5638266
    Abstract: The invention is directed to a neutral point clamped electric power conversion apparatus having four semiconductor switching elements connected in series. The capacity of outer free wheel diodes connected in reverse parallel with outer semiconductor switching elements are increased compared to that of inner free wheel diodes, thereby minimizing, an imbalance in losses between the inner and the outer free wheel diodes.
    Type: Grant
    Filed: March 10, 1995
    Date of Patent: June 10, 1997
    Assignees: Hitachi, Ltd., Hitachi Mito Engineering Co., Ltd.
    Inventors: Akira Horie, Syuuji Saitou, Hiroshi Itahana
  • Patent number: 5583385
    Abstract: In order to reduce an induction problem, which might otherwise be caused by a higher-harmonic current leaking to the outside of an inverter device, with a simple construction, an inverter device casing and a heat receiving plate mounted thereon are insulated from each other, and the heat receiving plate and a filter capacitor in the power supply circuit are connected through a predetermined inductance. Since the higher harmonics current is bypassed to the filter capacitor through the resonance filter which is formed by of the electrostatic capacity in a switching element and the inductance, the induction problem can be reduced by simple construction.
    Type: Grant
    Filed: June 14, 1994
    Date of Patent: December 10, 1996
    Assignee: Hitachi, Ltd.
    Inventors: Akira Horie, Syuuji Saitou, Takayuki Matui, Ken Itoh, Takashi Tsuboi, Eiichi Toyota
  • Patent number: 5506765
    Abstract: Disclosed is an apparatus for realizing a small apparatus by making element currents uniform in the dipolar modulation mode. The zero voltage period in the dipolar modulation period is made shorter than other voltage output periods. Accordingly, currents of switching elements constituting the main circuit of an inverter can be made uniform.
    Type: Grant
    Filed: April 23, 1993
    Date of Patent: April 9, 1996
    Assignee: Hitachi, Ltd.
    Inventors: Kiyoshi Nakata, Tokunosuke Tanamachi, Mutsuhiro Terunuma, Masato Suzuki, Kiyoshi Nakamura, Eiichi Toyota, Syuuji Saitou, Takayuki Matsui