Granted Patent
Utility
US 4,527,638 · App. 06/497,959
Mine tool roof bit insert and a method of drilling therewith
Inventors:
Jaime Sanchez, Vinod K. Sarin
Patented Case
View Patent ↗
Granted: Jul 9, 1985
Filed: May 25, 1983
Inventors
Jaime Sanchez
Vinod K. Sarin
Assignee (at issue)
GTE Laboratories Incorporated
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.