Granted Patent
Utility
US 6,572,712 · App. 09/737,172
Compacted graphite iron brake drum
Inventors:
William L. Powell, Paul D. Levering
Patented Case
View Patent ↗
Granted: Jun 3, 2003
Filed: Dec 14, 2000
Inventors
William L. Powell
Paul D. Levering
Assignees (at issue)
Waupaca Foundry, Inc.
Webb Wheel Products, 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.