Granted Patent
Utility
US 5,540,569 · App. 08/372,985
Multiple-chamber gear pump for ink jet printing
Inventors:
Tim J. Altham, Paul Johnson
Patented Case
View Patent ↗
Granted: Jul 30, 1996
Filed: Jan 17, 1995
Inventors
Tim J. Altham
Paul Johnson
Assignee (at issue)
Micropump, 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.