Patents by Inventor Shoji Hayashibe

Shoji Hayashibe 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).

  • Method and apparatus for non-destructively detecting defects in metal materials by using rotating magnetic fields generated by multiphase ac current
    Patent number: 4818935
    Abstract: Method and apparatus for non-destructive inspection of flaws in metal materials include exciting coils centered on a longitudinal axis of a cylindrical or columnar metallic material to be examined being arranged to surround the examinee material. A multiphase alternating current of such a relatively low frequency as to cause the exciting coils to generate a rotating magnetic field which rotates about the longitudinal axis of the examinee material is superimposed with a high frequency alternating current having an inspection frequency selected on the basis of the necessary sensitivity for detection of surface flaws of the examinee material. The composite multiphase current is applied to the exciting coils so that an electromagnetic effect induced in the surface of the examinee material by the high frequency alternating current is rotated for shifting circumferentially about the examinee material along with the rotating magnetic field.
    Type: Grant
    Filed: February 5, 1987
    Date of Patent: April 4, 1989
    Assignees: Nippon Steel Corporation, Eddio Corporation
    Inventors: Michiaki Takahashi, Mitsuo Yoshida, Kazuyoshi Miyazawa, Sigeyuki Nitta, Junichi Fujisawa, Nobuji Obara, Shoji Hayashibe, Yoshikazu Sawada