Granted Patent
Utility
US 4,182,122 · App. 05/878,141
Insulated exhaust manifold
Inventors:
Michael K. Stratton, Karl R. Engquist, Frank E. Keske, Harold C. Powers, James D. Sparks
Patented Case
View Patent ↗
Granted: Jan 8, 1980
Filed: Feb 15, 1978
Inventors
Michael K. Stratton
Karl R. Engquist
Frank E. Keske
Harold C. Powers
James D. Sparks
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.