Granted Patent
Utility
US 4,706,355 · App. 06/898,414
Method of making an internally grooved and expanded tubular heat exchanger apparatus
Inventors:
John P. Kuhns, James R. Taylor
Patented Case
View Patent ↗
Granted: Nov 17, 1987
Filed: Aug 21, 1986
Inventors
John P. Kuhns
James R. Taylor
Assignee (at issue)
Q-Dot, 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.