Granted Patent
Utility
US 4,685,487 · App. 06/840,845
Sanitary mixing valve
Inventors:
Dieter Derdack, Wilfried A. Delker
Patented Case
View Patent ↗
Granted: Aug 11, 1987
Filed: Mar 18, 1986
Inventors
Dieter Derdack
Wilfried A. Delker
Assignee (at issue)
American Standard 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.