Granted Patent
Utility
US 4,242,893 · App. 06/041,289
Stop collar for tube expander
Inventor:
Charles E. Diller
Patented Case
View Patent ↗
Granted: Jan 6, 1981
Filed: May 22, 1979
Inventor
Charles E. Diller
Assignee (at issue)
Dresser Industries, 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.