Patents by Inventor Hiroshi Asaga

Hiroshi Asaga 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 of diagnosing the deterioration of a zinc oxide type lightning arrester utilizing vector synthesis
    Patent number: 4866393
    Abstract: A method of diagnosing the deterioration of a zinc oxide type lighting arrester having one or more series-connected non-linear resistance elements including steps of elimination of the effects of capacitive currents from phase currents; obtaining a synthesized waveform using a window type transformer based on the resistance elements alone; and diagnosing the presence of a deteriorated non-linear resistance element by generating a first pulse voltage when the maximum crest value of the synthesized waveforms exceeds a predetermined value, generating a second pulse voltage representative of terminal voltage of the resistance element, and calculating the difference between the first and second pulse voltages.
    Type: Grant
    Filed: October 2, 1987
    Date of Patent: September 12, 1989
    Assignee: Fuji Electric Co., Ltd.
    Inventors: Hiromi Iwai, Masatoshi Nakajima, Hiroshi Asaga, Nobuyuki Takao, Satoru Shiga, Yoshihiro Tanabe