Granted Patent
Utility
US 4,199,131 · App. 05/836,154
Actuator module for wireline cutting safety valve
Inventors:
Israel Boski, Karl N. Tunstall, M. L. Warren
Patented Case
View Patent ↗
Granted: Apr 22, 1980
Filed: Sep 23, 1977
Inventors
Israel Boski
Karl N. Tunstall
M. L. Warren
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.