Granted Patent
Utility
US 5,353,548 · App. 08/040,457
Curl spring shoe based window balance system
Inventor:
Norman R. Westfall
Patented Case
View Patent ↗
Granted: Oct 11, 1994
Filed: Apr 1, 1993
Inventor
Norman R. Westfall
Assignee (at issue)
CALDWELL MANUFACTURING COMPANY
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.