Granted Patent
Utility
US 4,295,873 · App. 06/029,310
Method and apparatus for reworking a hollow workpiece
Inventors:
Donald G. Trutner, Luke Thorington
Patented Case
View Patent ↗
Granted: Oct 20, 1981
Filed: Apr 12, 1979
Inventors
Donald G. Trutner
Luke Thorington
Assignee (at issue)
Duro-Test 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.