Granted Patent
Utility
US 5,680,889 · App. 08/710,688
Low noise ball valve assembly
Inventor:
Henry W. Boger
Patented Case
View Patent ↗
Granted: Oct 28, 1997
Filed: Sep 23, 1996
Inventor
Henry W. Boger
Assignee (at issue)
Dresser Industries, 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.