Patents by Inventor Johann Wlodkowki

Johann Wlodkowki 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).

  • Yieldable roof support system
    Patent number: 5400994
    Abstract: A support includes a base member having an open end and a hollow interior, a forcing member having an end extending through the open end of the base member into the hollow interior thereof and having threads thereon and a mandrel or sliding nut capable of engaging the threads of the forcing member at an adjustable position and providing an interfering relationship between the base and forcing members as a compressive load is applied thereto. The support is particularly adapted for use in supporting the roof of a mine.
    Type: Grant
    Filed: April 10, 1992
    Date of Patent: March 28, 1995
    Assignee: Dyckerhoff & Widmann AG of Munich
    Inventors: Khaled Shawwaf, Johann Wlodkowki, Thomas Herbst, Ray Brandon