Granted Patent
Utility
US 4,243,870 · App. 05/876,467
Vaporizer with electrode housing interlock
Inventors:
Thomas E. Grime, Frank A. Robinson
Patented Case
View Patent ↗
Granted: Jan 6, 1981
Filed: Feb 9, 1978
Inventors
Thomas E. Grime
Frank A. Robinson
Assignee (at issue)
Champion Spark Plug Company
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.