Granted Patent
Utility
US 4,863,092 · App. 07/239,548
Apparatus for making a diaphragm assembly and method of making the apparatus
Inventor:
Ledu Nguyen
Patented Case
View Patent ↗
Granted: Sep 5, 1989
Filed: Sep 1, 1988
Inventor
Ledu Nguyen
Assignee (at issue)
ROBERTSHAW CONTROLS PRIVATE LIMITED
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.