Granted Patent
Utility
US 4,415,297 · App. 06/038,391
Vacuum material transporting system
Inventor:
Douglas J. Boring
Patented Case
View Patent ↗
Granted: Nov 15, 1983
Filed: May 14, 1979
Inventor
Douglas J. Boring
Assignee (at issue)
CONAIR 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.