Granted Patent
Utility
US 3,943,233 · App. 05/444,173
Processing finely divided solids on a continuous vacuum belt filter
Inventors:
David Benjamin Swanson, Walter L. Haden, Jr.
Patented Case
View Patent ↗
Granted: Mar 9, 1976
Filed: Feb 20, 1974
Inventors
David Benjamin Swanson
Walter L. Haden, Jr.
Assignee (at issue)
Engelhard Minerals & Chemicals 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.