Granted Patent
Utility
US 5,211,241 · App. 07/815,236
Variable flow sliding sleeve valve and positioning shifting tool therefor
Inventors:
Howard R. Mashaw, Jr., Christopher A. Dines, Robert C. Hammett, Clark E. Robison
Patented Case
View Patent ↗
Granted: May 18, 1993
Filed: Dec 31, 1991
Inventors
Howard R. Mashaw, Jr.
Christopher A. Dines
Robert C. Hammett
Clark E. Robison
Assignee (at issue)
Otis Engineering 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.