Granted Patent
Utility
US 4,327,776 · App. 05/868,606
Thin-walled metal duct having integral reinforced coupling ends
Inventor:
Robert Henry Meserole
Patented Case
View Patent ↗
Granted: May 4, 1982
Filed: Jan 11, 1978
Inventor
Robert Henry Meserole
Assignee (at issue)
Manville Service 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.