Granted Patent
Utility
US 4,601,715 · App. 06/614,892
Chest drainage device with sound muffling tube
Inventor:
Daniel H. Olson
Patented Case
View Patent ↗
Granted: Jul 22, 1986
Filed: May 29, 1984
Inventor
Daniel H. Olson
Assignee (at issue)
Snyder Laboratories, 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.