Granted Patent
Utility
US 5,662,335 · App. 08/621,443
Pressure balanced bellows seal
Inventor:
Richard R. Larsen
Patented Case
View Patent ↗
Granted: Sep 2, 1997
Filed: Mar 25, 1996
Inventor
Richard R. Larsen
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.