Granted Patent
Utility
US 4,257,901 · App. 06/065,808
Cleanable filter and method of cleaning same
Inventor:
Willard E. Rapp
Patented Case
View Patent ↗
Granted: Mar 24, 1981
Filed: Aug 13, 1979
Inventor
Willard E. Rapp
Assignee (at issue)
Western Electric Company, 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.