ALEXANDRIA, Va., March 12 -- United States Patent no. 12,250,531, issued on March 11, was assigned to Harman Becker Automotive Systems GmbH (Karlsbad, Germany).
"Loudspeaker" was invented by Andreas Helmut Pfeffer (Wenzenbach, Germany) and Maximilian Josef Kneilling (Hohenried, Germany).
According to the abstract* released by the U.S. Patent & Trademark Office: "A loudspeaker including a first diaphragm, a second diaphragm spaced from the first diaphragm, a first voice coil coupled to the first diaphragm, a second voice coil coupled to the second diaphragm, and a magnet assembly. The magnet assembly includes a magnet, a magnetic piece and a spacer of non-magnetic material connecting the magnet and the magnetic piece such that a gap is pro...