Granted Patent
Utility
US 6,423,217 · App. 09/662,690
Pool cleaner having vortex drive tube
Inventors:
Sanford F. Campbell, Suresh Gopalan
Patented Case
View Patent ↗
Granted: Jul 23, 2002
Filed: Sep 15, 2000
Inventors
Sanford F. Campbell
Suresh Gopalan
Assignee (at issue)
Letro 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.