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:
Jun. 17, 2008
Filed:
Jan. 27, 2004
Applicants:
Shigeru Tomoeda, Tsu, JP;
Takanori Fukuyama, Matsusaka, JP;
Masahide Sumiyama, Matsusaka, JP;
Inventors:
Assignee:
Matsushita Electric Industrial Co., Ltd., Osaka, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H04R 9/06 (2006.01); H04R 7/00 (2006.01);
U.S. Cl.
CPC ...
Abstract
A loudspeaker is provided that satisfies requirements for both a small size and a high sound pressure. In addition, the heat capacity of the magnetic circuit and the heat dissipation of the voice coil are improved in this loudspeaker. Using at least two pieces of bar magnets (), an outer magnet type magnetic circuit is structured in which the magnetic gap comprising an upper plate () and a lower plate () has a straight section. Also, the configuration of the voice coil () is that of a track.