Granted Patent
Utility
US 4,179,928 · App. 05/918,069
Push type thermal device and method of making the same and a stem seat therefor and method of making the same
Inventor:
Warren G. Williamson
Patented Case
View Patent ↗
Granted: Dec 25, 1979
Filed: Jun 22, 1978
Inventor
Warren G. Williamson
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.