Granted Patent
Utility
US 4,531,681 · App. 06/486,006
Flexible disk refiner and method
Inventors:
John B. Matthew, Edward C. Kirchner
Patented Case
View Patent ↗
Granted: Jul 30, 1985
Filed: Apr 18, 1983
Inventors
John B. Matthew
Edward C. Kirchner
Assignee (at issue)
Beloit 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.