Granted Patent
Utility
US 5,142,830 · App. 07/512,178
Abrasive cleaning machine
Inventor:
James H. Carpenter
Patented Case
View Patent ↗
Granted: Sep 1, 1992
Filed: Apr 20, 1990
Inventor
James H. Carpenter
Assignee (at issue)
Pangborn 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.