Granted Patent
Utility
US 3,977,639 · App. 05/587,444
Free fall safety assembly for use with a luminaire raise-lower apparatus
Inventors:
Brady Johnson, Robert Dale Zeller
Patented Case
View Patent ↗
Granted: Aug 31, 1976
Filed: Jun 16, 1975
Inventors
Brady Johnson
Robert Dale Zeller
Assignee (at issue)
Johns Manville
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.