Granted Patent
Utility
US 4,266,437 · App. 06/035,818
Ball screw and nut assembly
Inventor:
Bruno Obergfell
Patented Case
View Patent ↗
Granted: May 12, 1981
Filed: May 4, 1979
Inventor
Bruno Obergfell
Assignee (at issue)
Warner Electric Brake & Clutch Company
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.