Granted Patent
Utility
US 4,256,141 · App. 06/057,490
Relay valve for fluid actuators
Inventor:
Clifford M. Peters
Patented Case
View Patent ↗
Granted: Mar 17, 1981
Filed: Jul 13, 1979
Inventor
Clifford M. Peters
Assignee (at issue)
W-K-M Wellhead Systems, 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.