Patents by Inventor Tsay D. Wu

Tsay D. Wu 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).

  • Changeable key type lock barrel
    Patent number: 4729231
    Abstract: The present invention provides a lock barrel, particularly a changeable key type barrel which is characterized by using of a profile changing key to reset locking keys in the barrel by turning the barrel for 180 degrees and another profile changing key to restore the barrel to the original position by turning the barrel for 180 degrees but simultaneously the locking keys are pushed to different heights by means of some side plates to complete profile changing.
    Type: Grant
    Filed: December 29, 1986
    Date of Patent: March 8, 1988
    Inventor: Tsay D. Wu