Granted Patent
Utility
US 6,311,956 · App. 09/459,163
Hollow spindle with rectangular cross-section
Inventor:
Ronald D. Erwin
Patented Case
View Patent ↗
Granted: Nov 6, 2001
Filed: Dec 10, 1999
Inventor
Ronald D. Erwin
Assignee (at issue)
Erwin Industries, 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.