Granted Patent
Utility
US 4,815,532 · App. 07/018,155
Stack type heat exchanger
Inventors:
Hironaka Sasaki, Ryoichi Hoshino
Patented Case
View Patent ↗
Granted: Mar 28, 1989
Filed: Feb 24, 1987
Inventors
Hironaka Sasaki
Ryoichi Hoshino
Assignee (at issue)
Showa Aluminum Corp.
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.