Patents by Inventor David G. Jeffers

David G. Jeffers 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).

  • Triple tube viscosity testing instrument
    Patent number: D331202
    Type: Grant
    Filed: August 29, 1991
    Date of Patent: November 24, 1992
    Assignee: Louis C. Eitzen Co., Inc.
    Inventors: David G. Jeffers, Donald G. Pachuta