Granted Patent
Utility
US 4,337,868 · App. 06/122,506
Telescopic crane boom having rotatable extend/retract screws
Inventor:
Narahari Gattu
Patented Case
View Patent ↗
Granted: Jul 6, 1982
Filed: Feb 19, 1980
Inventor
Narahari Gattu
Assignee (at issue)
Harnischfeger 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.