Granted Patent
Utility
US 4,906,167 · App. 07/307,401
Inherently flushing piston rod for a reciprocating pump
Inventors:
Dragan Besic, Wilbur C. Smith
Patented Case
View Patent ↗
Granted: Mar 6, 1990
Filed: Feb 7, 1989
Inventors
Dragan Besic
Wilbur C. Smith
Assignee (at issue)
Dresser Industries, 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.