Granted Patent
Utility
US 4,515,524 · App. 06/423,534
Draft tube for hydraulic turbine
Inventor:
Richard K. Fisher, Jr.
Patented Case
View Patent ↗
Granted: May 7, 1985
Filed: Sep 27, 1982
Inventor
Richard K. Fisher, Jr.
Assignee (at issue)
Allis-Chalmers Corporation
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.