Granted Patent
Utility
US 4,184,146 · App. 05/791,909
Warning system
Inventors:
Lawrence F. Fratzke, Joe E. Fuzzell
Patented Case
View Patent ↗
Granted: Jan 15, 1980
Filed: Apr 28, 1977
Inventors
Lawrence F. Fratzke
Joe E. Fuzzell
Assignee (at issue)
Caterpillar Tractor Co.
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.