Granted Patent
Utility
US 4,957,169 · App. 07/475,629
Sprinkler valve assembly
Inventor:
George S. Polan
Patented Case
View Patent ↗
Granted: Sep 18, 1990
Filed: Feb 6, 1990
Inventor
George S. Polan
Assignee (at issue)
CENTRAL SPRINKLER 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.