Granted Patent
Utility
US 4,409,576 · App. 06/345,232
Method and apparatus which change magnetic forces of a linear motor
Inventor:
Christian C. Petersen
Patented Case
View Patent ↗
Granted: Oct 11, 1983
Filed: Feb 3, 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.