Granted Patent
Utility
US 4,469,152 · App. 06/088,241
Dust-tight hatch closure assembly
Inventors:
Carl L. Hardee, Robert E. Wagner
Patented Case
View Patent ↗
Granted: Sep 4, 1984
Filed: Oct 25, 1979
Inventors
Carl L. Hardee
Robert E. Wagner
Assignee (at issue)
Borg-Warner Chemicals, Inc.
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.