Granted Patent
Utility
US 4,654,141 · App. 06/831,535
In-line filter for a low pressure pool cleaning system
Inventor:
Herman E. Frentzel
Patented Case
View Patent ↗
Granted: Mar 31, 1987
Filed: Feb 21, 1986
Inventor
Herman E. Frentzel
Assignee (at issue)
Arneson Products, 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.