Granted Patent
Utility
US 4,026,322 · App. 05/657,180
Reciprocating pump check valve assembly
Inventor:
Benjamin A. Thomas
Patented Case
View Patent ↗
Granted: May 31, 1977
Filed: Feb 11, 1976
Inventor
Benjamin A. Thomas
Assignee (at issue)
Flow Industries, Ltd.
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.