Granted Patent
Utility
US 4,972,921 · App. 07/366,782
Muffler for internal combustion engines
Inventors:
Toshiyuki Takada, Hisayoshi Shibata
Patented Case
View Patent ↗
Granted: Nov 27, 1990
Filed: Jun 15, 1989
Inventors
Toshiyuki Takada
Hisayoshi Shibata
Assignee (at issue)
KAWASAKI JUKOGYO KABUSHIKI KAISHA
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.