Granted Patent
Utility
US 4,358,667 · App. 06/138,773
Cartridge-type electric immersion heating element having an integrally contained thermostat
Inventors:
Ronald Johnson, Stephen Hasty
Patented Case
View Patent ↗
Granted: Nov 9, 1982
Filed: Apr 10, 1980
Inventors
Ronald Johnson
Stephen Hasty
Assignee (at issue)
International Telephone and Telegraph 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.