Granted Patent
Utility
US 4,416,307 · App. 06/320,469
Valve assembly
Inventor:
Charles A. Detweiler
Patented Case
View Patent ↗
Granted: Nov 22, 1983
Filed: Nov 12, 1981
Inventor
Charles A. Detweiler
Assignee (at issue)
Schmelzer 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.