Granted Patent
Utility
US 5,238,472 · App. 07/862,319
Particle filter that can be regenerated by burning free for the exhaust gases of internal combustion engines
Inventors:
Wolfgang Pfister, Herbert Langen
Patented Case
View Patent ↗
Granted: Aug 24, 1993
Filed: Apr 2, 1992
Inventors
Wolfgang Pfister
Herbert Langen
Assignee (at issue)
J. Eberspacher
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.