Granted Patent
Utility
US 4,133,411 · App. 05/767,828
Extensible boom
Inventor:
Walter R. Curb
Patented Case
View Patent ↗
Granted: Jan 9, 1979
Filed: Feb 11, 1977
Inventor
Walter R. Curb
Assignee (at issue)
Chamberlain Manufacturing 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.