Patents by Inventor Martin Lieggi

Martin Lieggi 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).

  • Patent number: 5518352
    Abstract: An improved relief screw is provided for installing a wallboard panel to a stud, which consists of a flat head made of an inverted rectilinear slant height frustrum portion and a straight thin cylindrical portion. The straight thin cylindrical portion is larger than the widest part of the rectilinear slant height frustrum portion, therefore creating an annular flange thereabout. A threaded shank with a conical point extends from a narrow part of the rectilinear slat height frustrum portion, while the flat head bas a recess to accommodate a driving tool element for imparting rotary motion thereto. A structure is in the flat head for relieving particles of the wallboard panel therefrom, after the flat head is driven into the wallboard panel. The top of the straight thin cylindrical portion will be flush with and not damage the outer surface of the wallboard panel, while the annular flange will add more gripping support thereto.
    Type: Grant
    Filed: October 17, 1994
    Date of Patent: May 21, 1996
    Inventor: Martin Lieggi