Patents by Inventor Mitsuo Oooka

Mitsuo Oooka 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: 3998044
    Abstract: An electronic timepiece whose minimum dislay changing time interval is relatively long and is on the order of five seconds to two minutes such, as for example, an hour minute display liquid crystal timepiece or a two hand display crystal timepiece. This timpeiece is capable of measuring a time interval between changeable displays so as to calculate a pitch or stepping rate thereof by means of a display means. A driving circuit for driving the display means is supplied with a detecting repetition pulse having a pulse of a width such that the display means is not responsive to such a degree that naked eyes can follow the display.The detecting repetition pulse is delivered from a detecting signal generation circuit which is supplied with an output from an intermediate stage of a frequency division circuit.
    Type: Grant
    Filed: December 18, 1974
    Date of Patent: December 21, 1976
    Assignee: Citizen Watch Co., Ltd.
    Inventors: Masamichi Yamauchi, Yasuaki Nakayama, Mitsuo Oooka, Hiroharu Ohtsuka