Granted Patent
Utility
US 4,979,643 · App. 07/327,281
Chemical refill system
Inventors:
Bruce A. Lipisko, John C. Schumacher, Richard E. Howard, Peter T. Randke, Adrian Sandu, Robert E. Fletcher, Hans-Juergen Graf
Patented Case
View Patent ↗
Granted: Dec 25, 1990
Filed: Mar 22, 1989
Inventors
Bruce A. Lipisko
John C. Schumacher
Richard E. Howard
Peter T. Randke
Adrian Sandu
Robert E. Fletcher
Hans-Juergen Graf
Assignee (at issue)
Air Products and Chemicals, 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.