Granted Patent
Utility
US 4,800,925 · App. 07/081,740
Automobile coolant flow control
Inventor:
Roger L. Yeoman
Patented Case
View Patent ↗
Granted: Jan 31, 1989
Filed: Aug 5, 1987
Inventor
Roger L. Yeoman
Assignee (at issue)
Ranco Incorporated of Delaware
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.