Granted Patent
Utility
US 4,493,336 · App. 06/412,131
Hydraulic choking device
Inventor:
Wesley E. Renfro
Patented Case
View Patent ↗
Granted: Jan 15, 1985
Filed: Aug 27, 1982
Inventor
Wesley E. Renfro
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.