Granted Patent
Utility
US 4,688,641 · App. 06/889,539
Well packer with releasable head and method of releasing
Inventor:
Jeffrey L. Knieriemen
Patented Case
View Patent ↗
Granted: Aug 25, 1987
Filed: Jul 25, 1986
Inventor
Jeffrey L. Knieriemen
Assignee (at issue)
Camco 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.