Granted Patent
Utility
US 5,147,508 · App. 07/775,004
Suction box covers for cleaning papermaking machine felts
Inventor:
Douglas Sweet
Patented Case
View Patent ↗
Granted: Sep 15, 1992
Filed: Oct 11, 1991
Inventor
Douglas Sweet
Assignee (at issue)
The Nash Engineering Company
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.