Granted Patent
Utility
US 5,720,341 · App. 08/747,509
Stacked-typed duplex heat exchanger
Inventors:
Mikio Watanabe, Takayuki Yasutake, Shoichi Watanabe, Yuji Hasegawa
Patented Case
View Patent ↗
Granted: Feb 24, 1998
Filed: Nov 12, 1996
Inventors
Mikio Watanabe
Takayuki Yasutake
Shoichi Watanabe
Yuji Hasegawa
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.