Granted Patent
Utility
US 4,660,231 · App. 06/852,057
Automatic toilet bowl cleaner dispenser
Inventors:
Mark W. McElfresh, Martin E. Bellersen
Patented Case
View Patent ↗
Granted: Apr 28, 1987
Filed: Apr 15, 1986
Inventors
Mark W. McElfresh
Martin E. Bellersen
Assignee (at issue)
The Drackett Company
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.