Granted Patent
Utility
US 5,787,883 · App. 08/376,084
Spring-free pressure regulator with structure isolating exhaled air from valve
Inventor:
Robert L. Cramer
Patented Case
View Patent ↗
Granted: Aug 4, 1998
Filed: Jan 20, 1995
Inventor
Robert L. Cramer
Assignee (at issue)
Litton Systems, Inc.
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.