Patents by Inventor David C. Langevin

David C. Langevin 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).

  • Centralizer control
    Patent number: 3933208
    Abstract: An automatic control system for an adjustable, power operated drill string centralizer.
    Type: Grant
    Filed: May 16, 1974
    Date of Patent: January 20, 1976
    Assignee: Joy Manufacturing Company
    Inventors: Edward A. Bailey, David C. Langevin, James F. Ordway