Patents by Inventor Geoffery Chen

Geoffery Chen 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).

  • Structure of pencil sharpener
    Patent number: 5052453
    Abstract: A pencil sharpener, comprising an audio circuit reporter which gives audio signal to report that pencil has been well sharpened. The audio circuit reporter is comprised of an audio circuit, a dry battery and a speaker. The two opposite terminal ends of the audio circuit are respectively connected to two electric contacts which are electrically connected by the protruding pencil lead of the pencil which is well sharpened in the pencil sharpener, so that the audio circuit gives an audio signal through the speaker to report that the pencil which is inserted in the pencil sharpener has been well sharpened.
    Type: Grant
    Filed: November 26, 1990
    Date of Patent: October 1, 1991
    Inventor: Geoffery Chen