Granted Patent
Utility
US 4,897,797 · App. 07/185,752
Proportional chemical feeding system
Inventors:
Jerome J. Free, Jr., James C. Rodgers, Davie B. Lawhon
Patented Case
View Patent ↗
Granted: Jan 30, 1990
Filed: Apr 25, 1988
Inventors
Jerome J. Free, Jr.
James C. Rodgers
Davie B. Lawhon
Assignee (at issue)
Betz 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.