Granted Patent
Utility
US 4,644,597 · App. 06/726,608
Air mattress with pressure relief valve
Inventor:
Robert A. Walker
Patented Case
View Patent ↗
Granted: Feb 24, 1987
Filed: Apr 24, 1985
Inventor
Robert A. Walker
Assignee (at issue)
Dynatech 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.