Granted Patent
Utility
US 5,411,049 · App. 08/215,095
Valve
Inventor:
R. Lee Colvard
Patented Case
View Patent ↗
Granted: May 2, 1995
Filed: Mar 18, 1994
Inventor
R. Lee Colvard
Assignee (at issue)
Weatherford Holding U.S., 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.