Granted Patent
Utility
US 4,602,391 · App. 06/788,499
Dynamically balanced suction relief for hydrotherapy tubs and spas
Inventor:
Philip E. Shepherd
Patented Case
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Granted: Jul 29, 1986
Filed: Oct 17, 1985
Inventor
Philip E. Shepherd
Assignee (at issue)
Pearl Baths, 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.