Granted Patent
Utility
US 3,931,889 · App. 05/528,270
Tape cassette hub retainers
Inventor:
Harry I. Roccaforte
Patented Case
View Patent ↗
Granted: Jan 13, 1976
Filed: Nov 29, 1974
Inventor
Harry I. Roccaforte
Assignee (at issue)
Hoerner Waldorf 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.