Granted Patent
Utility
US 6,178,252 · App. 09/249,969
Electroacoustic transducer comprising a diaphragm having through portions for mounting a voice coil
Inventors:
Ewald Frasl, Erich Klein
Patented Case
View Patent ↗
Granted: Jan 23, 2001
Filed: Feb 12, 1999
Inventors
Ewald Frasl
Erich Klein
Assignee (at issue)
U.S. Philips Corporation
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.