Granted Patent
Utility
US 6,539,764 · App. 09/956,854
Air gap insulated exhaust pipe with branch pipe stub and method of manufacturing same
Inventors:
Pierre Bonny, Thomas Huelsberg
Patented Case
View Patent ↗
Granted: Apr 1, 2003
Filed: Sep 21, 2001
Inventors
Pierre Bonny
Thomas Huelsberg
Assignee (at issue)
Daimlerchrysler AG
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.