Granted Patent
Utility
US 4,491,428 · App. 06/325,608
Earth boring drill bit with snap ring cutter retention
Inventors:
Bruce H. Burr, George E. Dolezal, Edward M. Galle
Patented Case
View Patent ↗
Granted: Jan 1, 1985
Filed: Nov 27, 1981
Inventors
Bruce H. Burr
George E. Dolezal
Edward M. Galle
Assignee (at issue)
Hughes Tool Company LLC
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.