Granted Patent
Utility
US 4,340,366 · App. 06/236,642
Water/air spray system for dental handpiece
Inventor:
Donald J. Heil
Patented Case
View Patent ↗
Granted: Jul 20, 1982
Filed: Feb 23, 1981
Inventor
Donald J. Heil
Assignee (at issue)
American Hospital Supply Corp.
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.