Granted Patent
Utility
US 4,312,427 · App. 06/195,718
Extra lift mast for lift trucks
Inventor:
Robert N. Stedman
Patented Case
View Patent ↗
Granted: Jan 26, 1982
Filed: Mar 10, 1980
Inventor
Robert N. Stedman
Assignee (at issue)
Caterpillar Tractor Co.
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.