Granted Patent
Utility
US 4,458,227 · App. 06/367,361
Electromagnetic actuators
Inventor:
Christian C. Petersen
Patented Case
View Patent ↗
Granted: Jul 3, 1984
Filed: Apr 12, 1982
Inventor
Christian C. Petersen
Assignee (at issue)
Polaroid 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.