Granted Patent
Utility
US 4,997,420 · App. 07/458,506
Portable drug delivery device including pump with tapered barrel
Inventor:
Robert J. LeFevre
Patented Case
View Patent ↗
Granted: Mar 5, 1991
Filed: Dec 28, 1989
Inventor
Robert J. LeFevre
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.