Granted Patent
Utility
US 4,371,502 · App. 06/249,196
Crystal growing furnace pulling head
Inventors:
Clifton B. Sibley, Robert P. Bell
Patented Case
View Patent ↗
Granted: Feb 1, 1983
Filed: Mar 30, 1981
Inventors
Clifton B. Sibley
Robert P. Bell
Assignee (at issue)
Ferrofluidics 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.