Granted Patent
Utility
US 4,521,238 · App. 06/555,256
Method and apparatus for controlling an ablation liquefaction process
Inventor:
Robert B. Heithoff
Patented Case
View Patent ↗
Granted: Jun 4, 1985
Filed: Nov 25, 1983
Inventor
Robert B. Heithoff
Assignee (at issue)
PPG Industries, 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.