Granted Patent
Utility
US 4,638,229 · App. 06/765,752
Asymmetric torque switching for aircraft autopilot
Inventor:
Byron Birkedahl
Patented Case
View Patent ↗
Granted: Jan 20, 1987
Filed: Aug 15, 1985
Inventor
Byron Birkedahl
Assignee (at issue)
Sperry Corp.
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.