Granted Patent
Utility
US 4,516,178 · App. 06/418,492
Cylinder crossing detection circuit for disc drive or the like
Inventor:
Patrick S. Lee
Patented Case
View Patent ↗
Granted: May 7, 1985
Filed: Sep 15, 1982
Inventor
Patrick S. Lee
Assignee (at issue)
Ampex 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.