Granted Patent
Utility
US 4,529,038 · App. 06/409,455
Differential vent and bar actuated circulating valve and method
Inventor:
Emmet F. Brieger
Patented Case
View Patent ↗
Granted: Jul 16, 1985
Filed: Aug 19, 1982
Inventor
Emmet F. Brieger
Assignee (at issue)
Geo Vann, 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.