Granted Patent
Utility
US 4,236,402 · App. 06/031,575
Method and apparatus for testing rock tenacity
Inventor:
Robert C. McGuire
Patented Case
View Patent ↗
Granted: Dec 2, 1980
Filed: Apr 19, 1979
Inventor
Robert C. McGuire
Assignee (at issue)
Dresser Industries, Inc.
This patent predates the USPTO's electronic file wrapper — prosecution documents from this era exist only in the Patent Office's paper records. A certified copy of the file history can be ordered from the USPTO's paper archives.