Granted Patent
Utility
US 4,480,859 · App. 06/392,555
Flexible connector for flat wall ducting
Inventors:
Todd J. Rueckl, Craig T. Pahnke
Patented Case
View Patent ↗
Granted: Nov 6, 1984
Filed: Jun 28, 1982
Inventors
Todd J. Rueckl
Craig T. Pahnke
Assignee (at issue)
W. R. Grace & Co.
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.