Granted Patent
Utility
US 5,407,494 · App. 08/171,224
Method of fabricating a welded metallic duct assembly
Inventor:
Edwin E. Post
Patented Case
View Patent ↗
Granted: Apr 18, 1995
Filed: Dec 21, 1993
Inventor
Edwin E. Post
Assignee (at issue)
CRS HOLDINGS, LLC
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.