Granted Patent
Utility
US 4,483,702 · App. 06/496,221
Multiple chamber vacuum holder used to shape glass sheets with means to isolate adjacent vacuum chambers
Inventors:
Robert G. Frank, John J. Ewing
Patented Case
View Patent ↗
Granted: Nov 20, 1984
Filed: May 24, 1983
Inventors
Robert G. Frank
John J. Ewing
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.