Patents by Inventor Andrá Hardtmann

Andrá Hardtmann 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).

  • Annular composite workpieces and a cold-rolling method for producing said workpieces
    Patent number: 8161620
    Abstract: In a cold rolling method for producing annular composite workpieces, at least two hollow cylindrical workpieces made of different materials are inserted into one another. The at least two hollow cylindrical workpieces are roll formed by pressing the at least two hollow cylindrical workpieces against each other between two diametrically opposed external roll forming tools and an internal rolling arbor or between two diametrically opposed external roll forming tools and an internal roll forming tool to form a composite workpiece. The composite workpiece is a bearing ring or a gear ring. One of the hollow cylindrical workpieces can be a nonferrous material such as aluminum.
    Type: Grant
    Filed: July 8, 2004
    Date of Patent: April 24, 2012
    Assignee: Technische Universität Dresden
    Inventors: Thomas Ficker, Andrá Hardtmann, Mario Houska, Volker Thoms