Granted Patent
Utility
US 4,865,334 · App. 07/267,263
Long-life multi-stage ferrofluid seals incorporating a ferrofluid reservoir
Inventors:
Kuldip Raj, James Bonvouloir, Ronald Moskowitz, Frank Bloom
Patented Case
View Patent ↗
Granted: Sep 12, 1989
Filed: Nov 4, 1988
Inventors
Kuldip Raj
James Bonvouloir
Ronald Moskowitz
Frank Bloom
Assignee (at issue)
Ferrofluidics 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.