Granted Patent
Utility
US 4,834,873 · App. 07/233,163
Combined reverse osmosis unit and water inflow control valve for a water purification system
Inventor:
Bruce D. Burrows
Patented Case
View Patent ↗
Granted: May 30, 1989
Filed: Aug 17, 1988
Inventor
Bruce D. Burrows
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.