Granted Patent
Utility
US 5,738,156 · App. 08/748,633
Removable cutting blades for a helical cutterhead
Inventor:
John Sidney Stewart
Patented Case
View Patent ↗
Granted: Apr 14, 1998
Filed: Nov 13, 1996
Inventor
John Sidney Stewart
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.