Granted Patent
Utility
US 4,516,885 · App. 06/602,204
Method and apparatus for combining resin bonding and mechanical anchoring of a bolt in a rock formation
Inventor:
Frank Calandra, Jr.
Patented Case
View Patent ↗
Granted: May 14, 1985
Filed: Apr 19, 1984
Inventor
Frank Calandra, Jr.
Assignee (at issue)
Jennmar Corporation
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.