Granted Patent
Utility
US 5,839,436 · App. 08/512,129
Demand valve with a reduced manual flow control
Inventors:
Thomas F. Fangrow, Donald Rulifson
Patented Case
View Patent ↗
Granted: Nov 24, 1998
Filed: Aug 7, 1995
Inventors
Thomas F. Fangrow
Donald Rulifson
Assignee (at issue)
Life Support Products, 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.