Granted Patent
Utility
US 4,958,801 · App. 07/409,243
Valve construction and method of making the same
Inventor:
Harvey J. Shopsky
Patented Case
View Patent ↗
Granted: Sep 25, 1990
Filed: Sep 19, 1989
Inventor
Harvey J. Shopsky
Assignee (at issue)
ROBERTSHAW CONTROLS PRIVATE LIMITED
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.