The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 15, 2012
Filed:
Sep. 28, 2007
Koji Sano, Mie, JP;
Kazuki Honda, Mie, JP;
Satoshi Itoh, Mie, JP;
Masashi Kawabe, Mie, JP;
Panasonic Corporation, Osaka, JP;
Abstract
A loudspeaker includes a first bar magnet having a longitudinal direction, a second bar magnet having a longitudinal direction parallel to the longitudinal direction of the first bar magnet, a third bar magnet forming a second magnetic gap between the first bar magnet and the third bar magnet, a diaphragm arranged to vibrate in a vibrating direction, a case accommodating the first bar magnet, the second bar magnet, the third bar magnet, and the diaphragm , and the voice coil fixed to the diaphragm and located in the first and second magnetic gaps. The second bar magnet has a longitudinal direction parallel to the longitudinal direction of the first bar magnet, and has both ends in the longitudinal direction. The third bar magnet has a longitudinal direction parallel to the longitudinal direction of the first bar magnet, and has both ends in the longitudinal direction. The diaphragm is located between the first and second bar magnets and between the first and third bar magnents. The case is made of non-magnetic material and holds an outer periphery of the diaphragm. The case forms a first space surrounded by the case, one of the both ends of the second bar magnet, and one of the both ends of the third bar magnet. The case forms a second space surrounded by the case, another one of both ends of the second bar magnet, and another one of both ends of the third bar magnet. First and second sound holes are provided in the case and communicate with the first and second spaces, respectively. The loudspeaker is thin but outputs large sounds.