Granted Patent
Utility
US 4,502,973 · App. 06/466,337
Electroviscous fluids
Inventor:
James E. Stangroom
Patented Case
View Patent ↗
Granted: Mar 5, 1985
Filed: Feb 3, 1983
Inventor
James E. Stangroom
Assignee (at issue)
NATIONAL RESEARCH DEVELOPMENT CORPORATION
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.