Patents Assigned to Hammill Manufacturing
  • Method of making a bonescrew
    Patent number: 6551323
    Abstract: A screw for use in spinal and other surgical procedures has a tapered core and fixed pitch threads. The threads have a compound curved inferior surface and constant width crest. The screw may be provided with a helical thread in which at least the lead thread adjacent to the screw tip is ledged and the following threads have sharp apices. A method of making the screw requires two tool bits making two different angular cuts to the inferior surface of the threads.
    Type: Grant
    Filed: July 26, 2001
    Date of Patent: April 22, 2003
    Assignee: Hammill Manufacturing
    Inventors: Robert L. Doubler, John E. Hammill, Sr., Jeffrey Lasner