Granted Patent
Utility
US 6,443,224 · App. 09/862,061
Piping structure for heat exchanger, piping joint block for heat exchanger and heat exchanger with said joint block
Inventor:
Hironaka Sasaki
Patented Case
View Patent ↗
Granted: Sep 3, 2002
Filed: May 21, 2001
Inventor
Hironaka Sasaki
Assignee (at issue)
Showa Denko K.K.
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.