Granted Patent
Utility
US 4,328,402 · App. 06/070,279
Sensing switch for detecting a document
Inventor:
Daniel D. Call
Patented Case
View Patent ↗
Granted: May 4, 1982
Filed: Aug 27, 1979
Inventor
Daniel D. Call
Assignee (at issue)
Bell and Howell, LLC
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.