Granted Patent
Utility
US 6,009,596 · App. 09/004,501
Self-evacuating vacuum cleaner
Inventors:
Randy L. Buss, Robert C. Berfield
Patented Case
View Patent ↗
Granted: Jan 4, 2000
Filed: Jan 6, 1998
Inventors
Randy L. Buss
Robert C. Berfield
Assignee (at issue)
SHOP VAC CORPORATION
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.