Granted Patent
Utility
US 5,660,204 · App. 08/517,242
Tank blanketing valve
Inventors:
Thomas C. Piotrowski, William J. Zehr, Scott R. Diaz
Patented Case
View Patent ↗
Granted: Aug 26, 1997
Filed: Aug 21, 1995
Inventors
Thomas C. Piotrowski
William J. Zehr
Scott R. Diaz
Assignee (at issue)
THE PROTECTOSEAL 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.