Granted Patent
Utility
US 5,187,903 · App. 07/862,079
Method for removing accumulated ash from precipitators
Inventor:
William Holm
Patented Case
View Patent ↗
Granted: Feb 23, 1993
Filed: Apr 2, 1992
Inventor
William Holm
Assignee (at issue)
Allwaste, 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.