Granted Patent
Utility
US 4,273,290 · App. 06/092,888
Unitary valve and spring assembly
Inventor:
David Quinn
Patented Case
View Patent ↗
Granted: Jun 16, 1981
Filed: Nov 9, 1979
Inventor
David Quinn
Assignee (at issue)
AFA 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.