Granted Patent
Utility
US 4,531,423 · App. 06/539,452
Spring-assisted shift apparatus
Inventor:
Mark J. Fogelberg
Patented Case
View Patent ↗
Granted: Jul 30, 1985
Filed: Oct 6, 1983
Inventor
Mark J. Fogelberg
Assignee (at issue)
BorgWarner 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.