Patents by Inventor Donald R. Hofstetter

Donald R. Hofstetter 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: 4680068
    Abstract: A method and apparatus for forming a drum handling ring having an inverted frustoconical geometry to facilitate engagement of a conventional parrot beak gripper with the ring. The end of an advancing, straight strip of heated thermoplastic material, continuously provided by an extrusion head, is fed at a first location to the circular periphery of a continuously rotating, large diameter turntable where the strip is clamped thereto and then cooled so that the clamped portion of the strip thermally sets into an arcuate shape corresponding to the periphery of the turntable. At a second location diametrically opposed to the first, the now arcuate end portion of the strip is unclamped and guided away from the turntable periphery to a cutting station where the continuously advancing strip is cut into arcuate pieces each having an arc length generally corresponding to the desired circumference of a drum handling ring.
    Type: Grant
    Filed: July 7, 1986
    Date of Patent: July 14, 1987
    Inventors: Donald R. Hofstetter, Louis F. Fow, Jr.