Patents by Inventor David Takao Yamamoto

David Takao Yamamoto 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).

  • Electronic whistle device
    Patent number: 5847652
    Abstract: An electronic whistle device (10) comprising a casing (12). A whistle producing circuit (14) is carried within the casing (12). A manually operated switch (16) is remote from the casing (12). An assembly (18) is for electrically connecting the manually operated switch (16) to the whistle producing circuit (14) within the casing (12). When the manually operated switch (16) is closed, the whistle producing circuit (14) will be activated to make a whistle sound (20).
    Type: Grant
    Filed: September 30, 1997
    Date of Patent: December 8, 1998
    Inventor: David Takao Yamamoto