Granted Patent
Utility
US 4,375,291 · App. 06/300,152
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Inventor:
Arnold F. Padgett
Patented Case
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Granted: Mar 1, 1983
Filed: Sep 8, 1981
Inventor
Arnold F. Padgett
Assignee (at issue)
BorgWarner 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.