Granted Patent
Utility
US 4,557,467 · App. 06/640,692
Elbow of staircase hand rail
Inventor:
Ta-Chin Lin
Patented Case
View Patent ↗
Granted: Dec 10, 1985
Filed: Aug 14, 1984
Inventor
Ta-Chin Lin
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.