Granted Patent
Utility
US 4,530,377 · App. 06/521,486
Block valve
Inventor:
Clifford M. Peters
Patented Case
View Patent ↗
Granted: Jul 23, 1985
Filed: Aug 8, 1983
Inventor
Clifford M. Peters
Assignee (at issue)
Joy Manufacturing Company
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.