Patents by Inventor Charles B. Whittaker, Jr.

Charles B. Whittaker, Jr. 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).

  • Drill screw
    Patent number: 4147088
    Abstract: A drill screw comprising a threaded fastener with a drill bit formed on its entering end, the drill bit characterized by a bi-arc cross-section, that is the shape which is shared by two partially overlapping circles. Also disclosed are novel pinch point dies for making the drill bits and novel hobs for making the pinch point dies.
    Type: Grant
    Filed: March 16, 1977
    Date of Patent: April 3, 1979
    Assignee: NL Industries, Inc.
    Inventor: Charles B. Whittaker, Jr.