Granted Patent
Utility
US 4,352,375 · App. 06/140,173
Control valves
Inventor:
Arthur J. Williams
Patented Case
View Patent ↗
Granted: Oct 5, 1982
Filed: Apr 14, 1980
Inventor
Arthur J. Williams
Assignee (at issue)
Commercial Shearing, 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.