Granted Patent
Utility
US 4,656,721 · App. 06/672,992
Apparatus and methods for making rail-to-rung joints for ladders and joints for other structural elements
Inventor:
Richard Werner
Patented Case
View Patent ↗
Granted: Apr 14, 1987
Filed: Nov 19, 1984
Inventor
Richard Werner
Assignee (at issue)
R. D. Werner Co., 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.