Granted Patent
Utility
US 4,418,456 · App. 06/318,031
Tubular burner construction and method of making the same
Inventor:
Fred Riehl
Patented Case
View Patent ↗
Granted: Dec 6, 1983
Filed: Nov 4, 1981
Inventor
Fred Riehl
Assignee (at issue)
ROBERTSHAW CONTROLS PRIVATE LIMITED
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.