Granted Patent
Utility
US 5,457,841 · App. 08/323,448
Cleaning pig for pipeline of varying diameter
Inventor:
Joseph R. Minton
Patented Case
View Patent ↗
Granted: Oct 17, 1995
Filed: Oct 13, 1994
Inventor
Joseph R. Minton
Assignee (at issue)
Continental Emsco 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.