Patents by Inventor Wen K. Chao

Wen K. Chao 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).

  • Multi-blade pencil-core sharpener
    Patent number: 4934057
    Abstract: A sharpener, specially for the pencils, is made of a shell and a metal blade. At the upper end of the shell there is a funnel or alternatively two funnels placed side by side. The metal blade is V-notched or U-notched with the opening upward and is placed in the middle of the single funnel or in-between of the two funnels alternatively. The pencil core can be sharpened on the edge (sharped or right-angled) of the notch.
    Type: Grant
    Filed: April 27, 1988
    Date of Patent: June 19, 1990
    Inventor: Wen K. Chao