Granted Patent
Utility
US 4,757,764 · App. 06/811,731
Nonelectric blasting initiation signal control system, method and transmission device therefor
Inventors:
Gary R. Thureson, Ernest L. Gladden
Patented Case
View Patent ↗
Granted: Jul 19, 1988
Filed: Dec 20, 1985
Inventors
Gary R. Thureson
Ernest L. Gladden
Assignee (at issue)
The Ensign-Bickford Company
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.