Patents by Inventor Yoshio Umedu

Yoshio Umedu 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).

  • Small stepping motor
    Patent number: 5068562
    Abstract: A small stepping motor has a rotor comprised of a rotatably mounted and radially magnetized permanent magnet having a plurality of magnetic poles, a stator having a plurality of magnetic pole portions positioned to face the rotor, a coil wound around the stator, and a driving circuit for controlling the exciting current supplied to the coil. A leakage flux converging member is positioned in the vicinity of the stator so that leakage magnetic flux from the stator or the coil is converged by the leakage flux converging member so as to pass through the stator.
    Type: Grant
    Filed: November 17, 1989
    Date of Patent: November 26, 1991
    Assignee: Seikosha Co., Ltd.
    Inventors: Shigeru Tagami, Yoshio Umedu, Katsuhito Niwa