Granted Patent
Utility
US 4,383,642 · App. 06/242,634
Heater unit for use in an air conditioner for automotive vehicles
Inventors:
Seiji Sumikawa, Kazuo Utsugi
Patented Case
View Patent ↗
Granted: May 17, 1983
Filed: Mar 11, 1981
Inventors
Seiji Sumikawa
Kazuo Utsugi
Assignee (at issue)
Diesel Kiki Co., Ltd.
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.