Granted Patent
Utility
US 4,925,390 · App. 07/323,105
Apparatus for retaining the configuration of an aperture formed through a coil
Inventors:
Thomas J. Roman, Michael A. Ringle
Patented Case
View Patent ↗
Granted: May 15, 1990
Filed: Mar 10, 1989
Inventors
Thomas J. Roman
Michael A. Ringle
Assignee (at issue)
Aluminum Company of America
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.