Patents by Inventor Herbert D. Barnhart

Herbert D. Barnhart 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).

  • Contact fingers for a testing apparatus for surface insulation resistivity
    Patent number: 4156841
    Abstract: An improved Franklin tester for measuring surface insulation resistivity on magnetic sheets. The contact fingers of the prior art tester are modified to accommodate an articulated contact tip. The articulated tip pivots when the tester is clamped on a magnetic sheet to thereby maximize the area of contact. Preferably the articulated tips are formed of stainless steel to overcome the rapid deterioration of the prior brass contact fingers.
    Type: Grant
    Filed: December 15, 1977
    Date of Patent: May 29, 1979
    Assignee: General Electric Company
    Inventor: Herbert D. Barnhart