Granted Patent
Utility
US 4,216,732 · App. 06/059,865
Optical switching design for one step buttonholing
Inventors:
Walter H. W. Marsh, Howard L. Beckerman, Allan M. Dob
Patented Case
View Patent ↗
Granted: Aug 12, 1980
Filed: Jul 23, 1979
Inventors
Walter H. W. Marsh
Howard L. Beckerman
Allan M. Dob
Assignee (at issue)
The Singer Company Limited
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.