Patents by Inventor Sigeru Saito

Sigeru Saito 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).

  • Writing instrument having a needle slidably mounted in a tubular tip
    Patent number: 4522525
    Abstract: A writing instrument has a tubular tip and a needle longitudinally mounted within the tubular tip for enhancing the flow of ink towards a writing point of the tubular tip. The writing instrument has a mechanism which provides a smooth flow of ink without forming an air ring or bubble in the passage of the ink.
    Type: Grant
    Filed: June 23, 1983
    Date of Patent: June 11, 1985
    Assignee: Pentel Kabushiki Kaisha
    Inventors: Sigeru Saito, Takahiko Shimizu, Takasi Tamura