Granted Patent
Utility
US 4,246,928 · App. 06/095,911
Restricted movement valve seats for an expanding gate valve
Inventors:
Ivan A. Burns, William R. Hochmuth
Patented Case
View Patent ↗
Granted: Jan 27, 1981
Filed: Nov 19, 1979
Inventors
Ivan A. Burns
William R. Hochmuth
Assignee (at issue)
ACF Industries Incorporated
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.