Granted Patent
Utility
US 4,041,277 · App. 05/697,356
Portable tray warming unit
Inventors:
George K. Shumrak, Anthony C. Mack
Patented Case
View Patent ↗
Granted: Aug 9, 1977
Filed: Jun 18, 1976
Inventors
George K. Shumrak
Anthony C. Mack
Assignee (at issue)
Sweetheart Plastics, 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.