Patents by Inventor William J. Schafer

William J. Schafer 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).

  • Method and apparatus for the injection molding of metal alloys
    Patent number: 5040589
    Abstract: A method and apparatus for injection molding a metal alloy wherein the alloy is maintained in a thixotropic, semi-solid state in a reciprocating extruder at temperatures above its solidus temperature and below its liquidus temperature in the presence of shearing and then injected as a thixotropic slurry into a mold to form a useful product. Following completion of the injection molding stroke the nozzle of the extruder is sealed by a solidifying a portion of the residue of the alloy remaining in the nozzle.
    Type: Grant
    Filed: February 10, 1989
    Date of Patent: August 20, 1991
    Assignee: The Dow Chemical Company
    Inventors: Norbert L. Bradley, Regan D. Wieland, William J. Schafer, Allen N. Niemi