Granted Patent
Utility
US 4,552,158 · App. 06/657,264
Free air dilution smoke filter and method and apparatus for fabricating same
Inventor:
Richard M. Berger
Patented Case
View Patent ↗
Granted: Nov 12, 1985
Filed: Oct 3, 1984
Inventor
Richard M. Berger
Assignee (at issue)
American Filtrona Corporation
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.