Granted Patent
Utility
US 5,138,757 · App. 07/764,729
Process for manufacturing a vehicle brake drum
Inventors:
Richard C. Ball, Elvin E. Tuttle, David W. Kratzer
Patented Case
View Patent ↗
Granted: Aug 18, 1992
Filed: Sep 24, 1991
Inventors
Richard C. Ball
Elvin E. Tuttle
David W. Kratzer
Assignee (at issue)
Motor Wheel Corporation
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.