Granted Patent
Utility
US 4,784,039 · App. 07/026,951
Electric and pneumatic valve positioner
Inventor:
Chris M. Leinen
Patented Case
View Patent ↗
Granted: Nov 15, 1988
Filed: Mar 17, 1987
Inventor
Chris M. Leinen
Assignee (at issue)
Topworks, 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.