Granted Patent
Utility
US 6,186,448 · App. 09/149,195
Captivity point detection system with single switch position target
Inventors:
Leonard Wydotis, Daniel Brushwood
Patented Case
View Patent ↗
Granted: Feb 13, 2001
Filed: Sep 8, 1998
Inventors
Leonard Wydotis
Daniel Brushwood
Assignee (at issue)
Union Switch & Signal, 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.