Granted Patent
Utility
US 4,785,692 · App. 06/908,868
Railroad tie plug driver
Inventor:
Dennis Holmes
Patented Case
View Patent ↗
Granted: Nov 22, 1988
Filed: Sep 12, 1986
Inventor
Dennis Holmes
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.