Granted Patent
Utility
US 4,620,692 · App. 06/666,874
Crown block compensator
Inventors:
Fred R. Foreman, Douglas W. J. Nayler
Patented Case
View Patent ↗
Granted: Nov 4, 1986
Filed: Oct 31, 1984
Inventors
Fred R. Foreman
Douglas W. J. Nayler
Assignee (at issue)
NL Industries, Inc.
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.