Granted Patent
Utility
US 5,070,632 · App. 07/697,137
Trenching machine with laterally adjustable chain-type digging implement
Inventor:
Jerry F. Gilbert
Patented Case
View Patent ↗
Granted: Dec 10, 1991
Filed: May 8, 1991
Inventor
Jerry F. Gilbert
Assignee (at issue)
Trencor Jetco, 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.