Granted Patent
Utility
US 4,491,300 · App. 06/325,102
Valve with improved sealing structure
Inventors:
A. Kenneth Wilson, Ronald E. Barker
Patented Case
View Patent ↗
Granted: Jan 1, 1985
Filed: Nov 27, 1981
Inventors
A. Kenneth Wilson
Ronald E. Barker
Assignee (at issue)
AMSTED INDUSTRIES INCORPORATED
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.