Patents by Inventor Teruo Kawatsu

Teruo Kawatsu 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).

  • Mechanical filter
    Patent number: 4633204
    Abstract: A mechanical filter having as its major part at least one longitudinal vibration mode vibrator, includes a piezoelectric ceramic plate an electrode pair attached to top and bottom surfaces thereof. The piezoelectric ceramic plate is polarized in its thickness direction to form at least two polarized regions, the polarization directions being different from each other.
    Type: Grant
    Filed: August 26, 1985
    Date of Patent: December 30, 1986
    Assignee: Fujitsu Limited
    Inventors: Takashi Gounji, Shinichi Yamamoto, Teruo Kawatsu, Yoshiro Tomikawa, Masashi Konno, Toshiharu Ogasawara
  • Mechanical filter
    Patent number: 4555682
    Abstract: A mechanical filter including at least two longitudinal mode vibrators, each of which is a piezoelectric ceramic member with constant modulus alloy members mounted separately on the top and bottom surfaces thereof. The two constant modulus alloy members have the same configuration, a frequency-temperature characteristic opposite to that of the piezoelectric ceramic member, and are aligned, at their individual centers, with the center of the piezoelectric ceramic member. The configurations of the two longitudinal mode vibrators can be predetermined to suppress higher order spurious vibration modes inside the mechanical filter itself.
    Type: Grant
    Filed: February 23, 1984
    Date of Patent: November 26, 1985
    Assignee: Fujitsu Limited
    Inventors: Takashi Gounji, Teruo Kawatsu, Yoshihiko Kasai, Chikao Takeuchi