Granted Patent
Utility
US 4,284,018 · App. 06/090,714
Conversion assembly for sewing machine speed controller
Inventor:
Jan Szostak
Patented Case
View Patent ↗
Granted: Aug 18, 1981
Filed: Nov 2, 1979
Inventor
Jan Szostak
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.