Granted Patent
Utility
US 4,484,588 · App. 06/593,698
Combined concave and rock door structure
Inventors:
Michael L. Huhman, Michael Stüber
Patented Case
View Patent ↗
Granted: Nov 27, 1984
Filed: Mar 26, 1984
Inventors
Michael L. Huhman
Michael Stüber
Assignee (at issue)
Allis-Chalmers 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.