Granted Patent
Utility
US 5,390,489 · App. 08/134,814
Air-fuel ratio control system for internal combustion engine
Inventors:
Katsuhiko Kawai, Hisayo Douta
Patented Case
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Granted: Feb 21, 1995
Filed: Oct 12, 1993
Inventors
Katsuhiko Kawai
Hisayo Douta
Assignee (at issue)
Niopondenso 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.